Developmental expression of B cell molecules in equine lymphoid tissues
VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY
Authors: Prieto, J. M. B.; Tallmadge, R. L.; Felippe, M. J. B.
Abstract
Identification and classification of B cell subpopulations has been shown to be challenging and inconsistent among different species. Our study tested aspects of ontogeny, phenotype, tissue distribution, and function of equine CD5(hi) B cells, which represented a greater proportion of B cells early in development and in the peritoneal cavity. CD5(hi) and CD5(l0) B cells differentially expressed B cell markers (CD2, CD21, IgM) measured using flow cytometry, but similar mRNA expression of signature genes (DGKA, FGL2, PAX5, IGHM, IL10) measured using quantitative RT-PCR. Sequencing lambda light chain segments revealed that CD5(hi) B cells generated diverse immunoglobulin repertoires, and more frequently bound to fluorescence-labeled phosphorylcholine. This study shows developmental characteristics and tissue distribution of a newly described subpopulation of B cells in the horse. (C) 2016 Elsevier B.V. All rights reserved.
COMPARATIVE MAPPING OF IGHG1, IGHM, FES, AND FOS IN DOMESTIC CATTLE
IMMUNOGENETICS
Authors: TOBINJANZEN, TC; WOMACK, JE
Abstract
The immunoglobulin genes have not been genetically characterized as thoroughly in cattle as in other mammals, particularly humans and mice. Comparative gene mapping in mammals suggests that the bovine immunoglobulin heavy chain genes, IGHG4 and IGHM might be syntenic with the FOS oncogene. Interestingly, however, when these genes were assigned to bovine syntenic groups utilizing a panel of bovine: hamster hybrid somatic cells, IGH genes were shown to be syntenic with the FES oncogene rather than FOS. In this study IGH and FES were assigned to Bos taurus chromsome 21 while FOS was assigned to chromosome 10. In addition, bovine-specific immunoglobulin-like sequences were observed in the hybrid somatic cells, and one, IGHML1, was mapped to bovine syntenic group U16. The probes used for somatic-cell mapping were also used to screen a small number of cattle of several different breeds for restriction fragment length polymorphisms. IGHG4 and IGHM were shown to be highly polymorphic, while FOS and FES were not.