Antibody responses to Epstein-Barr virus in families with the X-linked lymphoproliferative syndrome.

This is the authors' abstract. We don't add key points for this paper.

EBV-specific antibody studies of males with the X-linked lymphoproliferative syndrome (XLP) reveal that fatal infectious mononucleosis (IM), acquired agammaglobulinemia, and malignant lymphoma phenotypes after EBV infection are associated with immune deficient responses to the virus. Sera from 15 patients with XLP, 21 female carriers, 69 healthy relatives, and 24 healthy unrelated controls were studied for EBV antibodies against early antigen (EA), viral capsid antigen (VCA), and EBV-associated nuclear antigen (EBNA). The 15 males with XLP, previously exposed to EBV, exhibited three patterns of reactivity: 1) six patients entirely lacked antibodies to VCA, EA, and EBNA; 2) six had anti-VCA with a geometric mean titer (GMT) of 1:110, but no anti-EA or -EBNA; and 3) three had anti-VCA (GMT 1:93) and anti-EBNA (GMT 1:4.6), but had no EA antibodies. Healthy, unrelated controls exhibited normal titers to VCA (GMT 1:100) and EBNA (GMT 1:54), but no anti-EA reactivity indicating remote EBV infection. The 21 carrier females of XLP exhibited a 3.5-fold greater anti-VCA titer (GMT 1:350) than controls and patients. In addition, four carriers had elevated anti-EA (GMT 1: 81). In contrast to their affected sons, all carriers with anti-VCA showed anti-EBNA. The deficient antibody responses in males with XLP to EBV-specific antigens, especially to EBNA, are probably due to defective T cells that fail to destroy EBV-infected B cells by natural or EBV-specific cytotoxicity. Alternatively, failure to develop immunity to EBV could arise from an intrinsic target cell defect of B cells. The paradoxically elevated anti-VCA and anti-EA of carrier females of XLP suggests that normal populations of lymphocytes prevent B cell proliferation. Lack of anti-EBNA in males within families with XLP having anti-VCA could identify affected males.