Production and the characterization of monoclonal antibody against CD43, K06

Abstract

A monoclonal antibody against human CD43 has been developed and designated as K06. Its reactivity in the lymphoid organs was different from that of known anti-CD43 monoclonal antibodies suggesting that this may recognize a novel epitope of human CD43 molecule. The CD43 epitope detected by anti-K06 monoclonal antibody was highly expressed in cortical thymocytes, platelets, and myeloid cells of normal peripheral blood, and its reactivity was comparable to that of known anti-CD43 monoclonal antibodies. However, the density of this epitope was lower in the medullary thymocytes. Biochemical studies indicated that anti-K06 monoclonal antibody could recognize glycosylated moiety of CD43 antigen. The expression profile of anti-K06 monoclonal antibody in several cell lines was somewhat different from that of known anti-CD43 antibodies. In addition, CD43 ligation through the K06 epitope appeared to induce apoptosis in human leukemic cell line, Molt-4. We therefore assume that K06 epitope of human CD43 might have some role in T-cell development.

CD43 cross-linking increases the Fas-induced apoptosis through induction of Fas aggregation in Jurkat T-cells

“…When the cells were treated with K06 mAb alone, apoptosis of Jurkat cells was not observed as previously reported (Park et al, 2004). In the cells treated with anti-Fas mAb CH11, Fas-induced cell death was observed in about 20% of the cells as previously described (Wallach et al, 1999).…”

“…Although CD43 ligation through the K06 epitope failed to induce apoptosis in Jurkat cells (Park et al, 2004), K06 signal enhanced Fas-mediated cell death (Figure 1). Apparently, this implies that the cell-specific environment, the nature of the CD43 epitope involved, or cell type-dependent changes in the glycosylation of CD43 could affect the final outcome of CD43-mediated signaling.…”

“…In this study, we evaluated the functional role of CD43 in T cell death using anti-CD43 mAb, K06, we produced (Park et al, 2004) and found another mechanism for CD43 to enhance apoptosis in Jurkat cells. Although CD43 ligation through the K06 epitope failed to induce apoptosis in Jurkat cells (Park et al, 2004), K06 signal enhanced Fas-mediated cell death (Figure 1).…”

“…The caspase inhibitors, z-VAD-fmk, z-DEVD-CHO, and z-IETD-fmk were from Calbiochem (La Jolla, CA). Anti-human CD43 mAb, K06, was produced and purified as previously described (Park et al, 2004). .…”

“…In addition, antiapoptotic and proapoptotic functions of CD43 have been reported. Certain studies have shown that engagement of CD43 induces apoptosis of T cells and hematopoietic progenitor cells (Bazil et al, 1995;Brown et al 1996;Cermak et al, 2002;Park et al, 2004). However, He and Bevan have reported that high level expression of CD43 inhibits T cell receptor (TCR)/CD3 mediated apoptosis (1999).…”