Region Groups and Subgroups

Forre et aL (1976) have developed subgroup-specific antisera to human myeloma heavy chains. The antisera were developed from heavy chains whose variable region amino acid sequences were known, thus providing a primary structural basis for the serology. A survey of 167 nonsequenced myeloma proteins showed a ratio of 1 2 3 for VhI VhII VhIII. This same group (Forre et aL, 1977) has detected Vh determinants on the surface of lymphocytes from patients with chronic lymphocytic leukemia. The number of patients studied is too small to allow conclusions to be drawn about distribution of Vh subgroups on the cell surface. 

Subgroup-specific antisera to mouse Vh subgroups have recently been reported by Bosma et al. (1977), but investigations establishing the presence of these subgroups on the cell surface remain to be done. 

Finally, it should be noted that the distribution of Vh subgroups in mn may be influenced to some extent by the ease with which amino acid sequencing can be accomplished. Since the VhI and VhII subgroups are blocked (pyrrolidone-5-carboxylic acid at the NHg-terminus), there are likely to be more sequences available for VhIII heavy chains. Thus we may have to wait for more extensive serology to be done before the exact distribution of subgroups or subsubgroups in man is well established. 

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