Molecular analysis of ocular adnexal lymphoid proliferations. Characteristics of immunoglobulin VH, D and J segment usage.

We investigated the molecular characteristics of six cases of ocular adnexal lymphoid proliferation. Although their clinical diagnoses varied, all of them were diagnosed as having malignant lymphomas by immunohistochemical examinations and molecular approaches. Proliferating cells showed the B cell phenotype, positive for L26/CD20 and negative for UCHL1/CD45RO, and genotypic study by Southern blotting revealed that all cases had gene rearrangements of the immunoglobulin heavy chain with or without those of the kappa (kappa) light chain. Epstein-Barr virus infection was not identified. Usage of variable domains of the immunoglobulin heavy chain was analyzed. Subgroup 3 of the VH gene was present relatively often, in 3 of 6 cases, perhaps due to its having the largest number of VH gene segments. On the other hand, an unexpectedly high frequency of the DLR family of the D gene segment was observed by sequencing the third complementarity determining region. These molecular characteristics in ocular adnexal lymphoid neoplasms might be related to the clinical course.