Expression Characteristics and Stimulatory Functions of CD43 in Human CD4+ Memory T Cells: Analysis Using a Monoclonal Antibody to CD43 That Has a Novel Lineage Specificity

摘要: We have used HSCA-2, an mAb that recognizes a sialic acid-dependent epitope on the low molecular mass (∼115-kDa) glycoform of CD43 is expressed in resting T and NK cells, to examine expression characteristics stimulatory functions human CD4 + memory cells. Having previously reported cells respond recall Ags CD45RO cell population almost all belong subset whose surface levels are elevated, we now find exposing these same HSCA-2 markedly increases their proliferative responsiveness Ags. think it unlikely this increase result CD43-mediated monocyte activation, especially given differs from mAbs having no obvious binding specificity for CD43. Predictably, treatment with did not lead significant responses were similar or lower than those naive Other experiments indicated was capable enhancing had been exposed polyclonal stimulation by monocyte-bound CD3 could also act synergy CD28 enhance stimulation. Taken together, findings suggest molecules may be costimulatory signaling hence providing accessory TCR-mediated activation processes.