Antigenic Changes Associated with Chicken B Lymphocyte Development

Abstract

Analysis of changes in specific antigenic determinants during ontogeny constitutes one of the most practical methods for investigating lymphocyte differentiation pathways. Such studies have been very successful in mice, using alloantisera specific for T cells (reviews 1,2), but those of B cells have been largely restricted to alteration in immunoglobulin subclasses (3). We have approached this problem by identifying heteroantigens specific for B or T lymphocyte subpopulations using the chicken as a model (4) because of the clear lymphoid tissue dichotomy. These determinants were the chicken B lymphocyte-specific antigen (CBLA), chicken mature B lymphocyte-specific antigen (CMBLA), chicken foetal-associated antigen (CFAA), chicken T lymphocyte-specific antigen (CTLA) and chicken thymus-specific antigen (CTOA). From the analysis of the adult cellular representation and tissue localization of these determinants and immunoglobulin (Ig) and IgG (4), there appeared to be a progression of cells bearing immature to mature markers, each subclass being associated with different elements of the microenvironment.