N. Nakamura et al., Analysis of the immunoglobulin heavy chain gene variable region of CD5-positive diffuse large B-cell lymphoma, LAB INV, 79(8), 1999, pp. 925-933
To clarify the cell origin of CD5+ diffuse large B-cell lymphoma (DLBCL), w
e analyzed and compared the variable region of the immunoglobulin heavy cha
in gene (VH gene) in eight cases of CD5+ DLBCL and 23 cases of other CD5+ B
-cell neoplasms; 10 cases of chronic lymphocytic leukemia (CLL), one case o
f small lymphocytic lymphoma, one case of hairy cell leukemia, and 11 cases
of mantle cell lymphoma. CD5+ DLBCL were comprised of two cases of de novo
lymphoma of nodal origin, five cases of de novo lymphoma of extranodal ori
gin, and one case of Richter transformation. Whereas all cases of mantle ce
ll lymphoma except one showed a germ line or low mutation frequency of the
rearranged VH gene, the rearranged VH genes in both CD5+ CLL and CD5+ DLBCL
were heterogeneous. The degree of somatic mutation of CD5+ CLL and CD5+ DL
BCL ranged between approximately 0 to 15.0% and 0.7 to 12.9%, respectively.
High frequency of expression of the VH4 family in both CD5+ CLL and CD5+ D
LBCL was found. Moreover, none of the three cases of CD5+ DFBCL examined ex
hibited intraclonal diversity. These findings may be common characteristics
of the rearranged VH gene of CD5+ CLL and CD5+ DLBCL and suggested that th
e cell origin of CD5+ DLBCL was the same as that of CD5+ CLL.