FUNC: In human MOLT-4 T-cell line the antibody M38 inhibits syncytium formation induced by coculture with human T-cell leukemia virus type 1 (HTLV-1)-positive human T-cell lines, Flow Cytometry: 1 ug/ml, WB: 1-2 ug/ml; Positive Control: Jurkat cells, Non-reducing conditions.