Maternal immunoglobulins have no effect on the rate of maturation of the B cell compartment of the offspring

Abstract

To elucidate a general role of maternal immunoglobulins (Ig) on the kinetics of B cell development of the offspring, we studied non-genetic influences of maternal Ig on the developing immune system of B cell-competent mice. These animals were the offsprings of either B cell-deprived microMT or of normal C57BL/6 females. In these mice, we have compared the kinetics of Ig production, the numbers of B cell progenitors, the expression of surface markers specific of the B lineage and the progression of Ig variable gene expression. We show that the absence of maternal Ig has no detectable effect on the kinetics of IgM and IgG production by the offspring's immune system. The number of B cell precursors, the kinetics of generation of B cells and their pattern of surface markers expression is identical in both types of mice. The acquisition of diversity in the B cell repertoire and the changes in the ratios of variable gene family expression are also indistinguishable. We conclude that maternally derived Ig has no influence on the rate of development and maturation of the B cell compartment of the offspring.

Pre-B cell receptor expression is necessary for thymic stromal lymphopoietin responsiveness in the bone marrow but not in the liver environment

“…We now show that BM pBCR-expressing cells have such an advantage, conferred by their response to TSLP. Fetal liver pro-B cells, however, respond to TSLP (19), which explains why pre-B cells are not in the majority in the FL (46). Expression of the pBCR was suggested to be sufficient to induce the proliferative expansion of pre-B cells, in the absence of exogenous growth factors (10).…”