We characterize the function of MHC molecules by the sets of pathogens that they recognize, which we call their "recognition sets." Two features of the MHC-pathogen interaction may be important to the theory of polymorphism construction at MHC loci: First, there may be a large degree of overlap, or degeneracy, among the recognition sets of MHC molecules. Second, when infected with a pathogen, a...

A high proportion of T cell clones derived from bulk cultures selected to M1s a,d determinants were found to have joint specificity for allo-H-2 determinants, and vice versa. Significantly, the patterns of H-2 alloreactivity shown by clones selected to M1sa,b determinants appeared to be random. The possible implications of these findings are discussed.

A lthough the MHC is a key genetic component in au-toimmune disease, our knowledge of the mechanisms by which the molecules encoded within the MHC influence autoimmune processes remains incomplete. Because of the linkage disequilibrium that exists among the class I, II, and III genes within the HLA complex in humans and the homologous MHC complex in rodents, the absolute contribution of the ind...

PURPOSE OF REVIEW Here, we review the pathways of allorecognition and their potential relevance to the balance between regulatory and effector responses following transplantation. RECENT FINDINGS Transplantation between nonidentical members of the same species elicits an immune response that manifests as graft rejection or persistence. Presentation of foreign antigen to recipient T cells can ...

The chicken major histocompatibility complex (MHC), or B complex, consists of several clusters of highly polymorphic genes, some of which are associated with disease resistance. The class I and class II antigens resemble their mammalian counterparts in the encoded protein structure. The class IV region encodes the B blood group antigens, which are readily identified by serological blood-typing....

The poultry immune system is a complex system involving many different cell types and soluble factors that must act in concert to give rise to an effective response to pathogenic challenge. The complexity of the immune system allows the opportunity for genetic regulation at many different levels. Cellular communication in the immune response, the production of soluble factors, and the rate of d...

Description The genes of the Human Leukocyte Antigen (HLA) system reside on chromosome 6, and code for cellsurface proteins that play a crucial role in the presentation of endogenic peptides to effector cells of the immune system. The HLA Class I protein molecule is a heterodimer, made up of two chains; a heavy one and a light one (beta 2 microglobulin). The HLA-B gene is one of the three HLA C...

A small subset of functionally active CD4+ CD8- thymocytes express the NK1.1 marker, as do most CD4-CD8- NK1.1+ thymocytes. Previous studies have failed to implicate a role for major histocompatibility complex (MHC) or related molecules in the selection of the CD4+ CD8- NK1.1+ subset. We report here that the development of most of these cells is sharply reduced in class I-deficient mice, but no...

The mapW gene of Staphylococcus aureus strain N315 contains a poly(A) tract which truncates translation of the protein. This study demonstrates that mapW is an allelic variant of the map/eap genes found in other strains and that the variation in the length of this poly(A) tract suggests that it is a contingency locus.

Despite widespread interest in the evolutionary implications of human olfactory communication, the mechanisms underlying human odor production are still poorly understood. Previous studies have demonstrated that human odor cues are related to variations in the major histocompatibility complex, but it is unclear whether odors are associated with overall genotypic variation. In this study, we inv...