CMTM7 and B-cell non-Hodgkin lymphoma: To confirm the plasma membrane localization of CMTM7 in B cells and examine possible changes in localization dynamics after ligation of surface IgM (sIgM), we made a mouse B-cell lymphoma cell line, BAL17, stably transfected with an expression construct encoding T7-tagged mouse CMTM7 (BAL17/T7-CMTM7).