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156 Cards in this Set
- Front
- Back
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Candida albicans
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*Dimorphic yeast
*Causes vaginal yeast infections (candidiasis) and oral thrush |
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Pneumocystis jirovecii (formerly carinii)
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*contracted from breathing in cysts
*in weakened immune systems can cause pneumonia |
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Histoplasma capsulatum
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*dimorphic fungus that causes histoplasmosis
*Bird and bat droppings harbor the spores of the fungus, and the disease is contracted by breathing in powdered droppings *General symptoms are similar to tuberculosis, and include fever, chest pain, dry or non-productive cough. A chest x-ray is used for diagnosis |
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Epidermophyton, and relatives
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*Epidermophyton and its relatives are slow
growing dermatophytes, causing skin, hair, and nail infections *Athletes foot (example) |
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Fungal diseases (types)
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*Fungal diseases called mycoses
**Superficial **Cutaneous **Subcutaneous **Systemic |
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Superficial fungal disease
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Infection of the superficial layers of skin. An example is tinia nigra, caused by Hortaea werneckii. Typically
asymptomatic, with dark discoloration of the skin, especially palms. |
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Cutaneous fungal disease
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where the skin, hair, or nails are infected. Often referred to as dermatomycosis. An example is
Trichophyton (athlete's foot) and ringworm. |
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Subcutaneous fungal diseas
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where the inner layers of skin are infected, typically from trauma in contact with soil or plants. A lesion or ulcer may result, spreading to the lymphatic
system. An example is Sporothrix schenckii, which causes sporotrichosis. |
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Systemic fungal disease
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An infection where internal organs are affected. Examples are meningitis caused by Candida, and
histoplasmosis. |
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Protozoa
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*Unicellular, non photosynthetic aerobic eukaryotes.
*Obtain nutrition by phagocytosis and absorption *Some form cysts (similar to spores) |
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Giardia lamblia
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*Protozoa
*causes giardiasis, common intestinal disorder *contracted by ingesting cysts from contaminated water or food *Symptoms : Mild to sever diarrhea 1-3 weeks, abdominal pain, cramps, nausea |
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Trichomonas vaginalis
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*Protozoa
*causes trichomoniasis (most common protozoan infection) *"strawberry cervix" |
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Leishmania donovani
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*Protozoa
*causes leishmaniasis (Kalazar- Black Fever, Dum-Dum Fever) *Transmitted via sandfly *Symptoms: fever, recurrent cutaneous & naso lesions & ulcers, enlarged liver & spleen |
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Trypanosoma brucei gambiense
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*Protozoa
*African Sleeping Sickness *parasite transmitted via tsetse fly *two cycles *starts with chancre @ bite site - spreads to blood & rest of the body |
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Entamoeba histolytica
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*Protozoa
*amoebic dysentery *contracted from cysts in water & food *Symptoms can range from diarrhea to dysentery *Chronic : appendicitis, pulmonary abscess, and anoperineal and genital lesions. |
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Naegleria fowleri
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*Protozoa
*causes meningo-encephilitis *inhalation of water spray (pool, A/C, ponds) *Symptoms: severe headache, fever, disorientation, leading to coma>death |
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Toxoplasma gondii
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*Protozoa
*Handling cat litter (cysts primarily ingested or inhaled) *symptoms include fever, chills, headache, and swollen lymph nodes |
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Plasmodium falciparum
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*Protozoa
*causes Malaria *transmitted via female mosquito *parasite has two life cycles *Symptoms: fever, chills, myalgia, weakness, anemia, and spleen enlargement; death may result |
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Viruses
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*Viruses are obligate intracellular parasites or infectious agents. They are very simple in structure and do not share the characteristics of living organisms.
*Viruses need to infect a host cell in order to replicate. They gain entry into the cell by docking with cellular receptors, a process which triggers endocytosis. Due to the docking requirement, viruses are host-specific as well as tissue-specific. |
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Viral Structure
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*Viruses consist of a crystalline protein coat called a capsid
*The capsid may be surrounded by a lipid membrane (envelope), which does not function in transport. Protein or glycoprotein spikes may be attached to the membrane *The capsid encloses the viral chromosome, which may be DNA or RNA, but not both. The nucleic acid can be single-stranded or double-stranded. |
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Different Replication Cycles
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*Lytic cycle
*Lysogenic cycle |
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Retroviruses
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*Retroviruses are a family of single-stranded RNA viruses that cause cancer, leukemia, and AIDS.
*A distinguishing feature of these viruses is the presence of an enzyme - reverse transcriptase - that is present within the viral capsid, and is required for viral pathogenesis |
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Influenza
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*Viral disease
*3 types: A, B, and C *Influenza viral types are distinguished by their two protein spikes, hemagglutinin (H) and neuraminidase (N). *Transmitted via aerosols *Symptoms: fever, sore throat, runny nose, fatigue, and myalgia *YES to vaccine |
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Measles
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*Viral disease
*Highly contagious respiratory infection in children *Spread via aerosols and direct contact *harsh cough, runny nose, white spots on gums, inside cheeks, and Koplik's spots on the palate. *YES to vaccine |
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Hepatitis A, E
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*Viral disease
*Infection of the liver *spread via unclean water & food *nausea, loss of appetite, fatigue *YES to vaccine (Havrix) |
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Hepatitis B, C
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*Viral disease
*Chronic infection of the liver *parenteral transmission *initial symptoms include jaundice, nausea, appetite loss, and fatigue. *later on leads to cirrhosis which can lead to liver failure or cancer. *YES to recombinant vaccine for Hep B *NO vaccine for Hep C |
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Adenovirus
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*consists of family of viruses (about 57)
*transmitted primarily via aerosols but also by direct contact *some cause respiratory illnesses such as bronchitis, pneumonia, sore throat, cold *others cause conjunctivitis & gastroenteritis |
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Genital Herpes
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*Genital herpes is most frequently caused by Herpes Simplex Virus type 2 (HSV2)
*Cold sores are primarily the result of an HSV1 infection. *HSV2 is sexually transmitted, and results in a permanent infection in the nerves *can be asymptomatic but otherwise there are sores - sores are infectious |
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Varicella/Zoster
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*Viral disease
*Chicken pox (HSV3) *Highly contagious *Transmitted via aerosols *Symptoms are an itchy rash forming blisters, and scabs, with fever and malaise, nausea, and loss of appetite. *YES to vaccine. 2 available (Varivax and Varilrix) |
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Kaposi's sarcoma
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*Viral disease
*Cancer of the skin caused by HSV8 *Transmitted by contact (kissing, sex, or through organ transplants) *Distinctive red, brown, or black blotches/nodules appear on the skin |
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SARS - Severe Acute Respiratory Syndrome
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*Viral disease
*coronavirus *highly contagious - transmitted via droplets or by contaminated surfaces *high fever, headaches, muscle pain, pneumonia *no cure, no vaccine *related to viruses from wild animals and birds - MUTATES RAPIDLY |
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Prions
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*Only class of pathogens that do NOT have nucleic acid - they are pure protein
*Cannot be destroyed by UV light *spongiform encephalopathy *humans contract be ingesting contaminated meat |
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How do prions replicate?
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prions are cellular proteins that somehow become aberrant, or abnormal, due to a misfolded 3-dimensional structure
*The misfolded protein PrPsc (sc = scrapie) promotes the formation of new prion protein from pre-existing normal protein PrPc (c = cellular) molecules, by interacting directly with them |
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Types of Specialized Media
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1. Selective
2. Differential 3. Reducing 4. Enriched |
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Selective Media
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media contain chemicals that inhibit the growth of unwanted bacteria. Examples are Eosin-methylene blue agar (EMB), and mannitol salt agar (MSA).
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Differential Media
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media contain chemicals that, if metabolized, show visible differences such as change in colony color. Examples are Starch,Milk, EMB, and MSA
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Reducing Media
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media contain chemicals that remove oxygen, permitting growth of anaerobes. Example is Selenite broth
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Enriched Media
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media contain additional nutrients for growing pathogens. Example is Blood agar
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Microbial Growth
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Growth, cell repair, and cell division are fundamental properties of living organisms, but can only occur if nutrients are available, and if the physical conditions are right.
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Basic Chemicals Nutrients cells need for growth
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Water (very important)
Carbon starch, sugars, cellulose, Nitrogen proteins, amino acids Sulfur sulfate, cysteine, methionine Phosphate soluble phosphates Minerals Ca, Mg, Na, K, Fe, Cr, Ni Some pathogens may require accessory growth factors such as vitamins, serum Oxygen (if the organism is aerobic) |
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Physical Conditions needed for growth
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1. Temperature
2. pH 3. Osmotic pressure |
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Cell Division (Prokaryotes)
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Prokaryotes multiply by binary fission (no mitosis)
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Binary Fission
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The division of one cell into two (typically similar or identical) cells by the formation of a septum. It is the commonest form of cell division in bacteria.
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Phases of Bacterial Growth
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1. Lag Phase
2. Exponential Phase 3. Stationary Phase |
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Sterilization
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Complete killing or inactivation of organisms. Validated process, has to be proven.
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Disinfection
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Reduction in number of organisms to a safe level on inanimate objects.
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Antisepsis
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Reduction in # of organisms to a safe level on tissues
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Sanitization
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Cleaning + disinfection (of rooms, work areas, utensils)
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Cidal Activity
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Refers to killing of organisms, but does not imply complete killing. Common terms are bactericide, fungicide, algicide, virucide
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Static Activity
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Preventing organisms from growing. No killing involved. Common terms are bacteriostatic, fungistatic
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Boiling
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*is a disinfection process where the material is heated at 100ºC for 10 min. It is commonly used for water and milk, at home.
*moist heat (Physical method) |
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Pastuerization
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is a disinfection method. The material is heated to 72ºC for 15 sec, and rapidly chilled. It is the rapid heating-cooling that causes the killing. Pasteurization is used commercially for milk, fruit juice, and cheese. (moist heat-physical method)
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Autoclaving
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is a very important
sterilization process. The material is treated with steam under pressure, 121ºC, for 20-40 min. It is used for liquids, glass, instruments, paper, and cotton. It cannot be used for oils or low temperature plastics, however, plastics for discard are suitable. In an emergency, pressure cookers with temperature/pressure gauges are usable. |
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Dry Heat
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kills organisms by exposure to high temperatures, primarily resulting in oxidation.
*Dry heat is a sterilization process where the material is heated at 180ºC for 2 hours. It is used for metal instruments, glass, and oils, but cannot be used for most plastics or paper. *Incineration is a sterilization process, where inoculating loops are heated to 600ºC. |
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Cold
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prevents organisms from growing. These are static processes.
*Refrigeration is used for storing foods and cultures at 4-10ºC for up to a week. *Freezing foods at -10 to -20ºC preserves them for months. |
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Radiation
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kills by extensively damaging DNA molecules.
Ultraviolet light is a disinfection process when 254 nm UV is used. This is commonly referred to as germicidal UV. UV lamps are used for rooms, cabinets, and water supplies. The surface must be directly exposed to radiation. *x-rays, γ-rays are sterilization processes. They have high penetrating power, and are used for treatment of prepackaged plastic disposables such assyringes. Food irradiation was re-approved by USDA, but is called “pasteurization”. *Electron beam irradiation is also a sterilization process, carried out on the prepackaged materials described above. |
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Filtration
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Filtration is a sterilization process when done correctly. Filters with pore size 0.1-0.2 µm hold back bacteria but NOT viruses. Virus-proof filters of pore size 0.01 µm also hold back large proteins. The process is used for solutions of antibiotics, vitamins, protein hormones, which cannot be sterilized any other way. HEPA filters are used for air "sterilization" in hospitals.
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Desiccation
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is a static process, and is used to preserve fruits, vegetables, bread, milk, beef, and fish.
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Osmotic Pressure
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is also a static process. High sugar concentrations are used in jams, jellies, and high salt is used to cure fish, beef, and venison.
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Oil Curing
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a static process, is used to cure olives in Morocco. In Brazil, meat is preserved under a layer of lard.
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Phenols
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are bactericidal and virucidal agents, causing denaturation of proteins, and
solubilize lipids They are used as disinfectants - Phenol (carbolic acid), cresol (lysol), and as antiseptics Hexachlorophene (toothpaste), triclosan (soaps, cutting boards). |
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Alcohols
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are bactericidal, virucidal, causing denaturation of proteins, and solubilize lipids. Water is necessary for activity, but the advantage is volatility – there are no residues left.
They work as disinfectants and antiseptics. 70% isopropanol is used in shower sprays, hand sanitizers, and towelettes. 95% ethanol is used in towelettes and handwash. In an emergency, use whiskey, vodka |
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Quaternary ammonium compounds
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are cidal agents, causing protein denaturation, and solubilizing phospholipids. They are highly effective against Gram-positive bacteria.
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Chlorhexidine
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is a highly effective antiseptic that works by solubilizing membrane phospholipids. It is effective against Gram-positive bacteria, Gram-negative bacteria, viruses, and fungi.
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Oxidizing Agents
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are cidal, and work by oxidizing proteins, lipids, and cellular components
Chlorine, iodine, ozone |
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Minimum Inhibitory Coefficient (MIC)
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Lowest conc. of chemical that kills specified organisms or prevents their growth
MIC indicates the minimal concentration at which chemical is effective. Typically 2x-5x MIC is used depending on tissue toxicity and chemical stability. |
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Examples of normal flora : Skin
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Staphylococcus aureus
Candida albicans Propionbacterium acnes |
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Examples of normal flora : Eyes
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Staphylococcus aureus
Staphylococcus epidermidis |
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Examples of normal flora : Nose, throat
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Staphylococcus aureus
Staphylococcus epidermis Streptococcus pneumoniae Neisseria meningitidis |
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Examples of normal flora : Mouth
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Streptococcus mutans
Lactobacillus sp. various Treponema sp. |
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Examples of normal flora : Stomach
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Helicobacter pylori
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Examples of normal flora : Intestine
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Escherichia coli
Enterobacter aerogenes Bacteriodes |
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Examples of normal flora : Urinary tract, genitals
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Lactobacillus
Staphylococcus Candida albicans Streptococcus Pseudomonas |
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Disease
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defined as a physiological change from a healthy state
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Infectious diseases
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caused by pathogens (TB, Hep)
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Genetic diseases
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caused by mutations (also called metabolic genetic disorders.
sickle cell, cystic fibrosis |
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Immunological diseases
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caused from malfunction of the immune system.
systemic lupus, asthma |
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Pathogen
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agent that causes infectious disease
Pathogens found among bacteria, fungi, protozoa, algae, viruses, viroids, and prions |
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Virulence
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the DEGREE of pathogenicity
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Portal of Entry
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the preferred entry point for a pathogen when it infects the body that will cause the most damage
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Method of Spread
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1. Non-communicable (tetanus, botulism)
2. Communicable (meningitis, salmonella) 3. Contagious (measles, chicken pox, influenza) |
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Acute
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Rapid development (influenza, gastroenteritis)
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Chronic
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Slow development, may be continual or recurrent (TB, syphillis)
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Latent
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Symptoms of the infection may not be seen for weeks, or months, or years (HIV, shingles)
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Local
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localized to a given area (ringworm, athletes foot)
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Focal
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starts as local, becomes systemic by spreading through the lymph, blood vessels
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Systemic
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internal organs affected, typical in latent stages of infection such as TB, candidiasis
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Bacteremia/Fungemia/Viremia
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presence of bacteria/fungus/virus in the bloodstream
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Septicemia
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multiplication of bacteria in the bloodstream
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Toxemia
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presence of bacterial, fungal, or viral toxins in the bloodstream
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Koch's Postulates
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Set of guiding principles to establish the causative agent of a disease.
The principles: • Pathogen must be present in all cases, and associated with the same symptoms • Must be isolated in pure culture from patient, i.e., in a Petri dish. • Administration of the isolated pathogen to a healthy individual must cause the same disease and symptoms • Upon re-isolation, the pathogen must be proven to be identical to the original pathogen |
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Exceptions to the postulates
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• Pathogen cannot be cultivated in vitro Mycobacterium leprae, Treponema pallidum
• Pathogen is not an organism, so "pure culture" is not possible Prions, viruses, viroids |
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Nosocomial Infections
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infections that are acquired in a health care facility -hospital or clinic (more commonly known as hospital-acquired infections)
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Contributing Factors to Nosocomial Infections
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1. Pathogens in the environment
2. Health status of the patient 3. Chain of transmission |
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Pathogens in the environment
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*many bacteria are opportunistic
*Drug-resistant bacterial strains in hospitals *Antibiotic misuse & overuse increases incidence of drug-resistance |
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Health status of the patient
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*Patients are sick - stress, infection, sores, wounds, diabetes...
*More prone to infections *Invasive procedures provide direct access to inner tissues - surgical incisions, catheters, IV drips, ventilators |
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Chain of Transmission
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*Physicians, nurses, aides, & visitors all have direct patient contact
*kitchen workers have indirect contact *Hospital ventilations systems can spread organisms when not cleaned regularly (AMA stats show 40% of physicians don't wash hands between patients) |
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Major organisms involved in Nosocomial infections
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Staphylococcus aureus, Enterococcus (34%)
>Surgical wounds, septicemia, UTIs E. coli, Enterobacter, Pseudomonas (32%) >Surgical wounds Clostridium difficile (17%) >Diarrhea C. albicans (10%) >UTIs, septicemia Misc Gram-negatives-Haemophilus, Citrobacter (7%) >UTIs, surgical wound infections |
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Control of nosocomial infections
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*Infection control nurse
*Proper aseptic procedures in handling materials *Enforce hand-washing *Monitoring of equipment - respirators, dialysis machines *Monitoring of personnel *Proper record keeping |
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In order for an organism to cause an infection is must do what?
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1. Gain entry into the body
2. Bypass, evade, or neutralize the body's primary defenses 3. Adhere to tissues and multiply 4. Produce toxins, enzymes, or chemicals that damage tissue |
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What are some examples of mucous membrane portals of entry?
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1. Respiratory tract
>Streptococcus pneumoniae, Influenza, Mycobacterium tuberculosis. 2. Gastrointestinal tract >Salmonella eneritidis, Hep A, Vibrio cholerae 3. Genitourinary tract >Treponema pallidum, Neissaria gonorrhoeae, HIV 4. Conjunctiva >Chlamydia trachomatis, Neisseria gonorrheae, Staphylococcus aureus (none use this as the primary route) |
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Skin as a portal of entry
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Openings in the skin, hair follicles, sebaceous glands, or wounds/abrasions
>Bacillus anthracis, Staphylococcus aureus, Clostridium tetani, Clostridium perfingens |
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Parenteral portal of entry
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Direct entry to the inner tissues & bloodstream via bites, wounds, punctures
>Plasmodium falciparum, Borrelia burgdorferi, Leishmania donovanii, plus those for skin |
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The Infectious Dose (ID50)
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is the minimum number of cells required to initiate an infection in 50% of test animals
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What is the ID (infectious dose) dependent on?
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1. The pathogen
2. Virulence of the strain 3. The host 4. The portal of entry |
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Lethal Dose (LD50)
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is a measure of virulence of the strain. It is the minim amount of toxin, or minimum number of cells required to kill 50% of test animals.
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What are some examples of virulence factors?
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*Fimbrae
*Capsules *Extracellular enzymes *Exotoxins *Endotoxins *Virulence plasmids *Lysogenic bacteriophages *Intracellular growth *Antigenic Variation *Biofilms |
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Virulence Plasmids
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*often carried by pathogens
*these plasmids code for proteins which can be exotoxins, extracellular enzymes, fimbrae, or provide antibiotic resistance. *Examples of plasmid-encoded proteins: >Tetanus toxin (Clostridium) >Toxic shock syndrome toxin (staphylococcus) >Coagulase (staphylococcus) >Fimbrae (enterotoxic E. coli) >B-lactamase (penicillin-resistance)(staphylococcus) >Anthrax toxin (Bacillus anthracis) |
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Phagocytosis
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the ingestion of bacteria or other material by phagocytes and ameboid protozoans.
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Extracellular enzyme
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and enzyme that functions outside the cell from which it originates
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What are some examples of extracellular enzymes in relation to pathogens?
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*Staphylococcus aureus produces coagulase in the bloodstream. A fibrin clot is formed around the cells, which protects them from the immune system. The bacteria multiply inside the clot, and then break through, to cause a major infection.
*Many Clostridium sp. produce collagenase, which breaks down connective tissue, and make a path for invading bacteria. *Streptococcus produces hyaluronidase, which breaks down hyaluronic acid, a tissue cement. |
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Exotoxins
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Protein toxins secreted by the cell and affect host physiology
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What are some examples of Exotoxins?
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*Botulinum toxin, produced by Clostridium botulinum, is a neurotoxin, and causes paralysis.
*Diphtheria toxin, produced by Corynebacterium diphtheriae, inhibits protein synthesis in host cells. *Tetanus toxin, produced by Clostridium tetani, is a neurotoxin. *Cholera toxin, produced by Vibrio cholerae, causes watery diarrhea. *Anthrax toxin, produced by Bacillus anthracis, causes hemorrhage and necrosis. *Scalded skin syndrome toxin, produced by Staphylococcus aureus, sloughs off the outermost layers of skin. |
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Endotoxins (lipopolysaccharides)
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*Produced by Gram-negative bacteria
*They induce fever, miscarriage, & cause tiny blood clots that block capillaries |
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What makes intracellular growth different than other pathogenic factors?
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*They hide & multiply INSIDE the host cell, evade the immune system, and move from cell to cell
*The host cell is DIRECTLY involved & actively participates in the interaction. *Pathogens interact with host cells via their adhesions *Endocytosis of the bacterium then occurs *Once inside, the bacterium multiplies *Migration to neighboring cells occurs by the bacterium riding the tip of the actin filament until it pokes through the membrane into the next cell *In this way, cells can travel through the tissue without ever leaving. |
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What are some examples of organisms capable of intracellular growth?
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1. Salmonella
2. E. coli 3. Listeria 4. M. tuberculosis 5. C. albicans 6. Vibrio cholerae |
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Where are some places biofilms may be found?
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1. Sewage treatment plants
2. Septic systems 3. Ship's hulls 4. Drinking water pipes, drains 5. Cooling towers |
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What is an acquired immune system?
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The acquired immune system is a surveillance system that recognizes cells, proteins, & components that are FOREIGN to the host. Distinguishes between "self" and "non-self"
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Self vs. Non-self
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Self: Material that belong to the body
Non-self: Foreign material of any conceivable shape in nature |
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What are some examples of foreign substances (non-self)?
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*Protein *Dust Particles *Viruses *Pollen grains *Bacteria *Fungal spores *Foreign tissues *Organs
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What are the two important characteristics the immune system has?
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1. The ability to RECOGNIZE billions of foreign shapes
2. The ability to REMEMBER shapes that were seen previously |
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What are the two branches of the immune system?
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1. Cell-mediated (T-lymphocytes)
2. Humoral (B-lymphocytes) |
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What are the 3 major classes of T-cells and what are they based on?
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The classes are based on additional specific proteins on the cell surface
1. CD8+ T-lymphocytes (cytotoxic T-lymphocytes) attack cells infected by bacteria, fungi, & viruses, as well as tumors. 2. CD4+ T-lymphocytes (Helper T-lymphocytes) are involved in the humoral response. 3. γδ cells - involved in wound repair |
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What is cell-mediated immunity?
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it's an immediate response that is activated whenever foreign cells are detected.
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What is humoral immunity?
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The humoral response is a slow response, developing over 10 days. It produces antibodies SPECIFICALLY targeted to the foreign substance, which is called an antigen.
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Antigens
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Molecules recognized as foreign by the immune system. Antigens that induce the immune system to produce antibodies are immunogens.
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Antibodies
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Defense proteins produced specifically in response to an immunogen.
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What are the 5 classes of antibodies?
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1. IgG - major class in blood. Crosses placenta, protects fetus (75% total)
2. IgA - Mucosal surfaces & secretions. (15-20% of total) 3. IgM - 1st antibody formed during immune response. Also found on macrophage cell surface & is involved in phagocytosis (5-10% total) 4. IgD - B cell surface, present during antibody development (<1% total) 5. IgE - Surfaces of mast cells, basophils. Associated with allergic reactions. Kills parasitic worms (<0.01%) |
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Macrophage
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a large phagocytic cell found in stationary form in the tissues or as a mobile white blood cell, esp. at sites of infection.
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What are some examples of Detection of antigens?
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Antibody of known specificity is used to test for the presence of antigen in unknown samples.
1. Blood typing 2. Rh factor determination 3. Identification of bacteria |
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What is quantitation of antigens and what are some examples?
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Purified antibody of known specificity used to quantify amount of antigen present
1. HIV screening (viral load) 2. hCG, LH levels |
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What does ELISA stand for?
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Enzyme-linked immunosorbent assay
*An enzyme is attached to the antibody molecules. *Antibody reaction with antigen is monitored by carrying out the enzyme reaction. *Product of the reaction is a colored compound and the amount of color depends on the amount of antibody attached. *Examples are pregnancy and hormone tests |
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What are vaccines?
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Vaccines are antigens deliberately administered to provoke an immune response in a healthy individual. They provide immunity against future infection.
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What are the different types of vaccines?
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1. Inactivated (killed) vaccines
2. Attenuated (live) vaccines 3. Toxoids 4. Recombinant vaccines 5. DNA vaccines |
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What are inactivated vaccines and what are some examples?
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*organism/virus inactivated by heat/chemicals
*antigenic properties still present >Salk polio vaccine >Whooping cough >Rabies >Smallpox |
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What are attenuated vaccines and what are some examples?
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*organism avirulent due to mutation
*more effective than killed vaccine >Sabine polio >Measles |
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What are toxoids vaccines and what are some examples?
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*Exotoxins inactivated by heat, formalin
*Antigenic properties still present >Tetanus >diptheria >anthrax >botulinum |
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What are recombinant vaccines and what are some examples?
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*protein antigen gene cloned in a host
*host secretes protein antigen which can be purified *safer than attenuated vaccines >Hep B >HPV (Giardisil) |
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What are DNA vaccines?
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*gene for the protein antigen is injected IM
*DNA taken up by muscle cells, protein expressed stimulates immune system *Currently in tests for safety |
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What is monoclonal antibody technology?
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is a process for making specific antibodies on a large scale. Technology relies on combining the inherent properties of two cell types : 1. B-cells 2. myeloma (tumor cell)
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What causes immune deficiencies?
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Immune deficiencies result from mutations affecting immune system development or function.
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What are some examples of immune deficiencies?
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1. Severe combined immune deficiency (SCID)
2. X-linked agammaglobulinemia 3. IgA deficiency 4. DiGeorge syndrome 5. Chronic granulomatous disease 6. C5 dysfunction |
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What is an autoimmune disease?
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When the immune system produces antibodies to body's own tissues (attacks itself)
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What are some autoimmune diseases?
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1. Myasthenia gravis
2. Hemolytic anemia 3. Rheumatoid arthritis 4. Systemic lupus erythematosus (SLE) 5. Multiple sclerosis 6. Insulin-dependent diabetes mellitus (IDDM) |
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Myasthenia gravis
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Abs against acetylcholine receptor, nerve conduction blocked
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Hemolytic anemia
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Antibodies against RBCs
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Rheumatoid arthritis
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Antibodies against IgG produced by B-cells that have migrated to the joints. Ag-Ab complex precipitates in the joint causing inflammation
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SLE (systemic lupus erythematosus)
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Abs against nuclei, chromosomes, RNA,…. Primarily affects women after pregnancy, causes kidney damage. Tumor suppressor PTEN is involved. Appears to be due to the presence of fetal cells that have migrated into the mother.
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Multiple sclerosis
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T-cells attack the myelin sheath, leading to disruption of nerve transmission
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Insulin-dependent diabetes
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T-cells attack glutamate decarboxylase in the pancreas preventing the secretion of the neurotransmitter glutamate, which is responsible for insulin secretion
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Diseases of the throat and respiratory system
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1. Streptococcus pyogenes (phayngitis)
2. Otitis media 3. Mycobacterium tuberculosis 4. Legionella pneumophila 5. Streptococcus pneumoniae 6. Klebsiella pneumoniae 7. Mycoplasma pneumoniae 8. Influenza |
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Diseases of the mouth and GI tract
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1. Streptococcus mutans
2. Helicobacter pylori 3. E. coli 4. Salmonella enteritidis 5. Clostridium difficile 6. Hepatitis A-E |
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Diseases of the urinary/reproductive tract
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1. Neisseria ginorrhoeae
2. Chlamydia trachomatis 3. HIV 4. Treponema pallidum 5. E. coli |
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Diseases of the nervous system
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1. Meningitis
2. Neisseria meningitis 3. Haemophilus influenza 4. Streptococcus pneumoniae |
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Diseases of the skin and eyes
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1. Staphylococcus aureus
2. Pseudomonas aeruginosa 3. Trachoma |
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Diseases of the cardiovascular system
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1. Septicemia & septic shock
2. Endocarditis 3. Lyme disease 4. Malaria |
