A monoclonal antibody that blocks poliovirus attachment recognizes the lymphocyte homing receptor CD44.

AUTOR(ES)
RESUMO

A monoclonal antibody, AF3, was previously shown to specifically inhibit poliovirus binding to HeLa cells and to detect a 100-kDa glycoprotein only in cell lines and tissues permissive for poliovirus infection. These results suggested that the 100-kDa protein may be involved in the pathogenesis of poliomyelitis and the cellular function of the poliovirus receptor site. To study further the role of the 100-kDa protein in poliovirus attachment, immunoaffinity purification, amino acid sequencing, and cDNA cloning were undertaken. The results demonstrate that antibody AF3 reacts with the lymphocyte homing receptor CD44, a multifunctional cell surface glycoprotein involved in the homing of circulating lymphocytes to lymph nodes and the modulation of lymphocyte adhesion and activation. Antibody AF3 reacts with a subset of CD44 molecules (AF3CD44H), which appears to be a small fraction of the heterogeneously glycosylated CD44 molecules expressed on hematopoietic and nonhematopoietic cells. Anti-CD44 monoclonal antibodies, previously reported to induce CD44-mediated modulation of lymphocyte activation and adhesion, compete with 125I-AF3 in binding assays, demonstrating functional overlap among the epitopes. The anti-CD44 monoclonal antibody A3D8, which binds to a greater molecular weight range of CD44 than does AF3, inhibits poliovirus binding to a similar degree. CD44 does not act as a poliovirus receptor, since CD44-expressing mouse L-cell transformants did not bind poliovirus. The poliovirus receptor and AF3CD44H may be noncovalently associated, or they may interact through the cytoskeleton or signal transduction pathways.

ACESSO AO ARTIGO

Documentos Relacionados