Elevated antibody levels to Epstein-Barr virus antigens in patients with hairy cell leukemia compared to controls in relation to exposure to pesticides, organic solvents, animals, and exhausts

Epstein-Barr virus (EBV) is a B-lymphotropic human herpes virus infecting B -cells, which has been associated with lymphoid malignancies, above all non -Hodgkin lymphomas (NHL. Severe immunosuppression is the best recognized ri sk factor for NHL, Many factors in the environment that have been described as risk factors for NHL cause measurable changes in immune functions. Hair y cell leukemia (HCL) is a rare, indolent non-Hodgkin lymphoma, originating from B-lymphocytes, This was a case-control study including 111 male cases with HCL and 400 controls. In a subgroup of 57 cases and 65 controls analy sis of antibodies to EBV early antigen, viral capsid antigen, and EBNA-1, m easured as P107, was performed. In this study, we confirm other studies des cribing elevated levels of antibodies to the EBV early antigen (EA) in pati ents with HCL compared to controls. We found only minor differences in the levels of antibodies to the viral capsid antigen (VCA) and EBNA-1, measured as P107. We found a positive association of a titer to EA IgG greater than or equal to 40 (OR 4.1: CI 1.9-9.5). The ORs were further elevated when su bjects with high levels of EA IgG and exposed to environmental agents such as organic solvents, certain pesticides, impregnating agents, animals, and exhausts were compared to those subjects with low levels that were not expo sed. Antibody reactivity against the EBV EBNA 1-alanine-glycine repeat (P10 7 IgG) above the median gave an increased OR for HCL, which further increas ed in subjects exposed to organic solvents, certain pesticides, impregnatin g agents, animals, and exhausts. However, the numbers of exposed cases and controls were small in some of the calculations.