Many chronic lymphocytic leukemia antibodies recognize apoptotic cells with exposed nonmuscle myosin heavy chain IIA: implications for patient outcome and cell of origin.

ABSTRACT: Many B-cell chronic lymphocytic leukemia (CLL) monoclonal antibodies (mAbs) can be grouped into subsets based on nearly identical stereotyped sequences. Subset 6 CLL mAbs recognize nonmuscle myosin heavy chain IIA (MYHIIA). Herein, we report that during apoptosis, MYHIIA becomes exposed on the cell surface of a subgroup of apoptotic cells, allowing subset 6 CLL mAbs to bind with it. Because other non-subset 6 CLL mAbs interact with apoptotic cells, 26 CLL mAbs, including 24 not belonging to subset 6, were tested for reactivity with MYHIIA-exposed apoptotic cells (MEACs). More than 60% of CLL mAbs bound MEACs well; most of these mAbs expressed unmutated IGHV (15 of 16) and belonged to a stereotyped subset (14 of 16). Binding to MEACs inversely correlated with the degree of IGHV mutation. In

SUBMITTER: Chu CC 

PROVIDER: S-EPMC2869555 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature