Serology Lec 16

Front 1

one parental gene cluster that is transmitted to the child

Back 1

Haplotype

Front 2

made up of the 2 haplotypes

Back 2

genotype

Front 3

HLA genes are

Back 3

co-dominant

Front 4

HLA antigens are

Back 4

polymorphic

Front 5

HLA class I antigens are expressed on all _______ cells

Back 5

nucleated

Front 6

HLA class I antigens are targets for

Back 6

cytotoxic t cells

Front 7

HLA class II are expressed on

Back 7

APC

Front 8

HLA class II display foreign peptides to

Back 8

Helper T cells

Front 9

Frequency of precursor T cells that respond to allogenic HLA antigens is 10 to 100 times than that of T cells that are specific to

Back 9

conventional antigens

Front 10

Code for the same gene product in every individual

Back 10

monomorphic genes

Front 11

Multiple alleles encode variant molecular forms

Back 11

Polymorphic Genes

Front 12

Every polymorphic protein is potentially a______ if introduced in an individual that lacks one of its alleles

Back 12

antigenic

Front 13

are polymorphisms that elicit a transplant response.

Back 13

histocompatability antigens

Front 14

Major Histocompatibility Antigens

Back 14

HLA class 1 and 2

Front 15

Consist of polymorphic proteins present in intracellular compartments
May cause graft rejection in HLA-identical siblings
Not a problem in recipients who receive adequate immunosuppression

Back 15

Minor histocompatability antigens

Front 16

system is important in transplantation

Back 16

ABO

Front 17

A and B antigens are present on

Back 17

endothelia and some epithelia

Front 18

Since IgM antibodies to A and B antigens are naturally occurring, the donor and the recipient must be ______ to prevent rejection

Back 18

ABO compatible

Front 19

tissue or organs transferred from an individual of one species to an individual of another species.

Back 19

xenograft

Front 20

tissue or organs transferred from one individual to another of the same species

Back 20

allograft

Front 21

tissue or organs transferred between identical twins.

Back 21

syngraft

Front 22

tissue is removed from one part of the body and re-introduced elsewhere in the same individual.

Back 22

autograft

Front 23

Recipient T cells recognize HLA molecules on donor APCs
Predominates in early post-transplant period
Elicits strong cytotoxic T cell response

Back 23

Direct allorecognition pathway

Front 24

Donor HLA peptides are bound to recipient HLA II molecules and presented to recipient helper T cells
T cells help B cells make antibodies t the donor HLA antigens
Predominates in most acute rejections and in chronic rejection

Back 24

Indirect allorecognition Pathway

Front 25

the recipient’s immune system attacks & attempts to reject the graft.

Back 25

Host-versus-graft response

Front 26

may occur if the graft is an organ that contains a large number of lymphoid cells.

Back 26

Graft-versus-host response

Front 27

T cells from the graft react with recipient

Back 27

alloantigens

Front 28

4 types rejection responses

Back 28

Hyperacute and Accelerated Rejection
Acute Rejection
Chronic Rejection
Graft-Versus-Host-Disease

Front 29

Caused by antibodies to ABO groups or to HLA antigens
Complement & coagulation cascades are activated

Back 29

hyperaccute and accelerated rejection

Front 30

Hyperacute rejection occurs within _______ after joining graft and recipient blood vessels.

Back 30

minutes to hours

Front 31

Accelerated rejection occurs

Back 31

within the first 5 days

Front 32

results in organ shutdown

Back 32

severe rejections

Front 33

Greatest risk of graft loss during 1st year

Mediated by cytotoxic T lymphocytes

Usually occurs within first 3 months of transplant

Severity is unpredictable

Episodes can be treated with increased doses of immunosuppressive drugs.

Back 33

Acute Rejection

Front 34

Mediated by T and B lymphocytes

Occurs through a process of graft arteriosclerosis characterized by:
Progressive fibrosis
Scarring of arteries

Usually due to injuries from:
Acute rejection episodes
Toxicity of immunosuppressive agents
Proliferation of smooth muscle cells

Back 34

Chronic Rejection

Front 35

Chronic Rejection Occurs through a process of graft arteriosclerosis characterized by

Back 35

Progressive fibrosis
Scarring of arteries

Front 36

Chronic rejection usually due to injuried from:

Back 36

Acute rejection episodes
Toxicity of immunosuppressive agents
Proliferation of smooth muscle cells

Front 37

Transplanted lymphoid cells react against recipient alloantigens

Acute GvHD causes skin rashes, diarrhea, and increased susceptibility to infections.

Chronic GvHD leads to fibrosis and atrophy of skin, eyes, mouth, & other mucosal surfaces.

Back 37

graft vs host

Front 38

Most at risk are recipient of (graft vs host)

Back 38

Bone marrow
Small bowel
lung

Front 39

Histocompatibility (HLA) labs have 3 main functions in clinical organ transplants:

Back 39

Prevent hyperacute or acute rejection due to donor-reactive antibodies
Improve overall graft survival rates by minimizing the number of HLA incompatibilities
Monitor HLA sensitization status before and after the transplant

Front 40

Donor-Recipient Crossmatch Test

HLA Antigen Phenotype

Panel-Reactive Antibody and HLA Specificity Analysis

DNA-Based HLA Genotyping

Back 40

histocompatability test

Front 41

creates an increased risk for infections, especially involving opportunistic viral infections.
Example – CMV infection

Back 41

immunosuppresive agents

Front 42

used to prevent rejection and to reverse rejection episodes

Back 42

Immunosuppresive agents

Front 43

cells that have undergone malignant transformation, also called tumor cells

Back 43

Neoplastic cells

Front 44

the travel of neoplastic cells through blood or lymph vessels to other parts of the body.

Back 44

metastatic growth

Front 45

antigens present in the tumor tissue in higher amounts than in normal tissue.

Back 45

tumor associated antigens

Front 46

A good screening test should have:

Back 46

99% sensitivity, 95%s specificity

Front 47

An antigen must meet 5 strict requirements to be useful for screening the general population:

Back 47

Must be produced by the tumor & secreted into a biological fluid
Must have a half-life long enough for it to increase with increasing tumor load
Must increase to clinically significant levels while the disease is still treatable
Must not give too many false positives
Must not give too many false negatives

Front 48

immunoglobulin light chains in urine.
Used to screen for multiple myeloma

Back 48

Bence Jones protein

Front 49

– high amounts present in:
Multiple myeloma
Macroglobulinemia
Heavy chain disease

Back 49

Monoclonal immunoglobulin

Front 50

an oncofetal antigen (present in tumor tissue and in tissues of fetal origin)

Back 50

alpha-fetoprotein

Front 51

Used with AFP to screen for testicular cancer

Back 51

hCG

Front 52

hCG Screens for gestational tumors such as

Back 52

hydatiform mole

Front 53

Used with hCG to screen for testicular cancer
Screens for primary hepatoma (liver cancer

Back 53

afp

Front 54

diagnostic marker for:
Medullary thyroid carcinoma

Back 54

Calcitonin

Front 55

Used to screen for prostate cancer

Back 55

prostate specific antigen

Front 56

Used to screen for ovarian cancer

Back 56

CA-125