DNA Based Tissue Typing Flashcards
MHC
Major Histocompatibility Complex. A group of genes located on the short arm of chromosome 6.
HLA
Human Leukocyte Antigens. MHC gene products.
Allografts
A transplanted organ from a genetically different donor.
Tissue Typing
HLA identification, performed initially by serological methods using antibodies to the different HLAs found in the human population.
MLC
Mixed Lymphocyte Culture. Measurement of growth of lymphocytes activated by serum antibodies as an indication of donor/recipient incompatibility; co-culturing of lymphocytes from unrelated individuals to determine HLA type.
xMHC
extended MHC locus. 8-Mb region of chromosome 6p including areas flanking the main MHC locus.
HLA Type
A collection of alleles in the major histocompatibility locus coding for different human leukocyte antigens and detected by phenotypic or genotypic typing methods.
Haplotype
A genetically linked set of alleles that are inherited together.
Split Specificities
Antigenic types derived from a parent antigen.
Synonymous Changes
Silent mutations.
Null Allele
A genetic type or variant with no phenotypic effect.
Ambiguity
The recognition of two or more antigens by the same antibody.
Crossmatching
More specific screening of recipient sera for antibodies against antigens displayed by potential organ donors.
Crossmatching
Analysis of the reaction between recipient serum antibodies and donor lymphocytes.
CDC
Complement-dependent Cytotoxicity. Killing of cells based on HLA type using reference antigens.
CREGs
Cross-reactive Epitope Groups. Human leukocyte antigens recognized by antibodies that also recognize other HLAs.
Private Antibodies
HLA type-specific antibodies.
AHA
Alloantibodies. Anti-human Antibodies. Antibodies that recognize human antigens.
Hormonal Sensitization
Development of anti-human antibodies, often due to organ transplant, blood transfusion, or pregnancy.
PRAs
Panel Reactive Antibodies. A set of reference antibodies used to define the HLA of reference lymphocytes.
SSOP
Sequence-specific Oligonucleotide Probe. Detection of DNA polymorphism using amplified test DNA immobilized on a filter exposed to labeled probes that will hybridize to specific sequences.
SBT
Sequence-based Typing. Determination of HLA DNA polymorphisms by direct sequencing.
mHags
Minor Histocompatibility Antigens. Proteins outside the main MHC locus that affect organ engraftment.
KIR Proteins
Killer Cell Immunoglobulin-like proteins. These proteins are expressed by NK cells and some memory T cells and interact with HLA receptors.
Hybrid Resistance
The effect of KIR proteins. Rejection of transplanted organs by immunocompromised mice.
Leukocyte Receptor Cluster
A group of genes on the long arm of chromosome 19 coding for the killer cell immunoglobin-like receptors.
