Purified anti-human CD100

CD100, a 150 kD homodimer, is a novel semaphorin that induces B cells to aggregate and improves their viability in vitro. Semaphorins are neuronal chemorepellants that direct pioneering neurons during nervous system development. CD100 modifies CD40-CD40L B cell signaling by augmenting B cell aggregation and survival and down regulating CD23 expression. CD72 is a lymphocyte receptor for the class IV semaphorin CD100, which is involved in regulating B cell signaling. CD100 is expressed on resting and PHA stimulated T cells. The protein is weakly expressed on NK cells, EBV transformed B cells, monocytes and tumor/peripheral blood T cell lines, and at higher density on activated T cells and B cells.