Disease relevance of BoLA

• In addition to the practical significance of these findings, the association between BoLA and BLV provides a unique model to study host resistance to retrovirus infection in a non-inbred species [1].
• Disease association studies have demonstrated that BoLA alleles affect the subclinical progression of bovine leukemia virus (BLV) infection [1].
• We have analysed the influence of bovine MHC (BoLA) polymorphism on the immune response and degree of protection induced by peptide vaccines against foot-and-mouth disease (FMD) in cattle [2].
• This investigation was to determine whether immune responsiveness differed between these cows and whether differences were related to expression of class I BoLA antigens, which might explain the increased resistance or susceptibility to S. aureus mastitis [3].
• BoLA antigens are associated with increased frequency of persistent lymphocytosis in bovine leukaemia virus infected cattle and with increased incidence of antibodies to bovine leukaemia virus [4].

High impact information on BoLA

• This review focuses on recent advances in research on the bovine major histocompatibility complex (BoLA), with specific reference to the genetic organization, polymorphism and function of the class II genes [1].
• Two cDNA cloned from a Hereford cow B cell line (BL-3) have allowed the determination of the complete coding region for two class I molecules encoded by the bovine MHC (BoLA) [5].
• The BoLA proteins show greater similarity to HLA than to H-2 molecules, correlating with the cross-reactions of W6/32 and other murine anti-HLA-A,B,C mAb with BoLA molecules [5].
• Evidence for the expression of three different BoLA-class II molecules on the bovine BL-3 cell line: determination of a non-DR non-DQ gene product [6].
• Accepted nomenclature convention suggests that BoLA-DIB should therefore be renamed BoLA-DYB [7].

Chemical compound and disease context of BoLA

• The BoLA W8.1 allele was negatively associated with the presence of antibodies to the major BLV envelope glycoprotein, BLV-gp51 (corrected P less than 0.001, relative risk = 0.31) [8].

Biological context of BoLA

• Full-length cDNAs encoding the DQB genes expressed by three BoLA class II haplotypes (DH8A, DH15B, and DH24A) were amplified by reverse-transcription polymerase chain reaction, cloned, and sequenced [9].
• To test for involvement of the bovine major histocompatibility system (BoLA) the MLR tests were done using full-sibling cattle families which had been generated through the use of embryo transfer systems [10].
• Cytotoxic cells of bovine origin were generated in primary MLC using stimulator cells of BoLA w8/w11 phenotype [11].
• Sequence diversity present within the 5' upstream regions of BoLA class I genes [12].
• Since the tests, were done using full-sibling combinations, this result suggests genetic linkage between the MLR controlling antigens and the BoLA complex [10].

Anatomical context of BoLA

• Lymphocytes from six full-sib families, ranging in size from three to seven siblings, were tested for serologically defined BoLA antigens (BoLA-A) [13].
• Results suggest that BoLA restricted cells are established in the immunological memory and are probably analogous to cytotoxic T cells, while non-BoLA restricted cytotoxic cells are natural killer like cells [14].
• Studies using antibodies to bovine MHC class II and BoLA DR-transfected CHO cells as antigen-presenting cells indicated that immunodominant regions of the F and G proteins contained both DR- and DQ-restricted epitopes [15].
• We have mapped the bovine gene to Chromosome (Chr) 23 in a panel of somatic cell hybrids and observed genetic linkage to the major histocompatibility complex (BoLA) genes and microsatellite markers on bovine Chr 23 in an international bovine reference family panel [16].
• Alloimmunizations with either lymphocytes or red cells from donor cows positive for BoLA w16 and blood group M' antigens into recipients negative for these antigens produced antisera reactive in the cytotoxic test with w16-positive lymphocytes and in the haemolytic test with M'-positive erythrocytes [17].

Associations of BoLA with chemical compounds

• Lymphoblastoid cell lines, infected and transformed in vitro by a Moroccan stock of Theileria annulata, infected and immunized susceptible taurine cattle, at cell doses of 10(8), 10(6), 10(4) and 10(2), regardless of whether the recipients were BoLA matched or mismatched to the donor cell line [18].

Physical interactions of BoLA

• In these animals we studied several highly polymorphic genetic systems such as haemoglobin, albumin, the BoLA Complex (class I and II) and the gamma S crystallin gene [19].

Other interactions of BoLA

• This was achieved by in vitro expression of allele *2703 as well as a control allele, BoLA-DRB3*1201 which is present at high frequency in Holsteins [20].
• The microsatellites BoLA-DRBP1 and CSSM66 were nonneutral markers according to the Ewens-Watterson test, suggesting some kind of selection imposed on these loci [21].
• Prolactin was found to be syntenic with previously mapped glyoxalase, BoLA and 21-hydroxylase genes, establishing a syntenic conservation with human chromosome 6 [22].
• These data provide additional evidence that the BoLA DQA3 locus is distinct from BoLA DQA1 and BoLA DQA2 [23].

Analytical, diagnostic and therapeutic context of BoLA

• It is now possible to type for human leucocyte antigen (HLA) DR-like bovine MHC (BoLA) class II polymorphisms with a one-dimensional isoelectric focusing (IEF) technique [24].
• Immunoprecipitation experiments with monomorphic anti-B2m and anti-HLA-DR monoclonal antibodies have shown that these cross-reactions concern BoLA antigens [25].
• One-dimensional isoelectric focusing followed by immunoblotting and development of the immunoblots with the monoclonal antibody HC-10, raised against denatured HLA class I heavy chains, was used to demonstrate biochemical variation in cattle MHC (BoLA) class I molecules [26].
• DNA typing for BoLA class I using sequence-specific primers (PCR-SSP) [27].
• Fourteen BoLA specificities were detected in the herd using a standard lymphocyte microcytotoxicity test [28].

References