DavidT. Purtilo

EPSTEIN-BARR-VIRUS-INDUCED ONCOGENESIS IN IMMUNE-DEFICIENT INDIVIDUALS

Experimental and clinical evidence supports the notion that the Epstein-Barr virus (EBV) can become oncogenic in immune-deficient hosts. Renal transplant recipients and children with inherited immune deficiency are at high risk for lymphomagenesis. Defective immune responses to EBV permit persistence of polyclonal proliferation of B cells. Conversion from polyclonal to monoclonal proliferation is probably the result of a cytogenetic error in a B cell. This hypothesis can be tested prospectively in patients with immune deficiency by immunological, EBV, and genetic studies.

EPSTEIN-BARR VIRUS INFECTIONS IN THE X-LINKED RECESSIVE LYMPHOPROLIFERATIVE SYNDROME

Prospective studies demonstrated variable phenotypic expression of the X-linked recessive lymphoproliferative syndrome (X.L.R.L.S.) in three brothers: (1) hypogammaglobulinaemia and subclinical Epstein-Barr-virus (E.B.V.) infection with antibody response to E.B.V.; (2) E.B.V. infection with defective immune response to E.B.V., fatal infectious mononucleosis (I.M.), and immunoblastic lymphoma; and (3) histiocytic lymphoma. Hypogammaglobulinaemia and measles pneumonitis had preceded infection with E.B.V. The diverse phenotypic expressions probably resulted from the varied immune response to E.B.V. Recombination of X chromosomes was documented by Xg-blood-group studies in a survivor. E.B.V. can induce fatal I.M. and malignant lymphoma in X.L.R.L.S., but an immune response to E.B.V. can be protective.