Popis: |
Nonrandom use of immunoglobulin variable (V) gene segments is a feature of some B-cell neoplasms, possibly as a consequence of antigen selection. In Hodgkin's disease, the primary tissues, cell lines, and even single Reed-Sternberg cells can carry immunoglobulin gene rearrangements. Here, we examined the immunoglobulin heavy-chain genes of a well-characterized Hodgkin's-derived cell line, L428, and found a hypermutated VH32 gene involving a conventional V(N)D(N)J4-C gamma 4 rearrangement. VH32 is one of two rearranging members of the VH5 family that is also rearranged preferentially in some B-cell neoplasms and familial CLL. Unexpectedly, the closest known rearranged sequence match for the rearranged VH gene of L428 was found in the single Reed-Sternberg cells of lymphocyte-predominance Hodgkin's disease, and is a mutated VH251, the only other rearranging member of the VH5 family. Assuming random usage of the human VH pool, the chance of coincident VH5 family gene rearrangement in the two cases of Hodgkin's disease is only about 10(-3). Biased use of VH genes suggests a B-cell target that is either selected by antigen or vulnerable to transformation at an early antigen-independent, developmental stage. These findings raise the question whether similar processes operate in Hodgkin's disease. |