TABLE 2.

MJ cells also express high levels of MHC class II molecules^a

MAb	MT2		MJ		K562/VCAM-1
	% Pos	MCF	% Pos	MCF	% Pos	MCF
H53	99.8	976	99.9	949	1.4	14
MT.M1	99.7	768	99.9	672	0.3	15
MT.M2	99.3	876	99.9	921	9.6	19
MT.M3	99.4	893	99.9	985	8.0	19
MT.M4	99.6	948	99.8	887	5.8	18
H5C6	89.4	21	99.8	39	94.2	62
MHM.5	99.3	923	99.9	441	0.9	14

^aThe indicated MAbs were tested for binding to MJ, MT2, and K562/VCAM-1 cells by flow cytometry as described in Materials and Methods. Data shown are percent positive cells relative to an isotype-matched myeloma IgG (% Pos) and the intensity of staining, shown as MCF. MAbs H53, H5C6, and MHM.5 recognize class II MHC, CD63, and class I MHC, respectively.