Association of EB-virus infection with the post-perfusion syndrome

Epstein-Barr virus infection following bone-marrow transplantation

A 12-year-old patient with acute lymphoblastic leukemia received a bone-marrow transplant (BMT) from a matched sibling donor. Nine weeks prior to transplant the donor experienced Epstein-Barr virus (EBV)-induced infectious mononucleosis. The bone-marrow recipient was EBV-negative at the time of transplant; however, 4 weeks post transplant the recipient developed clinical symptoms of graft-verus-host disease (GVHD) coincident with serological evidence of acute EBV infection. In addition, a lymphoblastoid cell line positive for Epstein-Barr nuclear antigen was established from a bone-marrow sample obtained at the onset of symptoms compatible with GVHD. Sera obtained from the recipient over the ensuing 2 months showed the appearance of antibodies to specific EBV antigens consistent with a primary immune response to EBV infection. This association of acute EBV infection with symptoms of GVHD in a BMT recipient suggests a need for further investigation of the epidemiology of EBV infections in human bone-marrow transplantation and the relationship between EBV infection and GVHD.

Epstein-Barr herpesvirus infection: inhibition by immunologically induced mediators with interferon-like properties

When sensitized leukocytes were re-exposed to EBV antigen or to tuberculin-purified protein derivatives, they produced lymphokines, including the migration inhibition factor, which inhibited the migration of guinea-pig peritoneal exudate cells, and other lymphokines with the characteristics of interferon, which inhibited EBV-induced transformation and EBV superinfection of target cells. Unsensitized leucocytes from sero-negative adults and from neonates did not produce lymphokines when challenged with the antigens. This indicates that cell-mediated immunity and its associated soluble mediators may be involved in the control of EBV infection and that the interferon release assay is a useful in vitro correlate for the study of cellular immunity to EBV.

HBs-Ag-negative hepatitis in a hemodialysis unit: relation to Epstein-Barr virus

Eleven of 40 patients in a hemodialysis unit had clinical or biochemical evidence of hepatitis during a five-week period. The clinical disease was mild, being limited solely to dialysis patients. Epidemiologic investigation indicated that the incubation period was between 17 and 35 days and that 10 of 11 patients had been exposed to a single venous-pressure monitor before onset. Dried blood and evidence of blood reflux up the venous-pressure gauge suggested that cross-contamination of the blood of successive patients probably resulted in transmission of disease. No association with the hepatitis B surface antigen or anti-hepatitis B antibody was demonstrated, but 10 of the 11 patients with elevated transaminase levels had evidence of recent exposure, to Epstein-Barr virus as manifested either by Ox-cell hemolysin titers or rises in titers to viral capsid antigen.

Isoimmune haemolysis in pathogenesis of anaemia after cardiac surgery

A patient who had received multiple transfusions developed antiglobulin-positive haemolytic anaemia due to a delayed haemolytic transfusion reaction. Many cases of haemolytic anaemia after cardiac surgery could be explained on this basis.

Observations on the type of infection by Epstein-Barr virus in peripheral lymphoid cells of patients with infectious mononucleosis

Transformation to continuous cell lines has been studied in cultures of peripheral leuckocytes from infectious mononucleosis (IM) patients and in co-cultures of IM leukocytes and foetal cord blood leukocytes of opposite sex. The transformed cells in the co-cultures were of mixed origin with foetal cells usually predominating. Neutralizing antisera to EB virus markedly reduced or abolished the incidence of transformation in IM leukocyte cultures. This effect was not due to cytotoxicity and followed the pattern seen with cultures where transformation was known to depend on the inter-cellular transfer of infectious EB virus. The findings suggest that EB virus is harboured in peripheral lymphocytes of IM patients as a non-productive unexpressed infection which is activated to produce virus in vitro, the particles released then infecting neighbouring cells to give transformed lines. The differences between this mechanism and the one whereby lines arise in culture from malignant cells of Burkitt's lymphoma are considered, and their significance is discussed.

Antibodies to Epstein-Barr and other viruses in children with acute lymphoblastic leukaemia

Sixty-eight children with acute lymphoblastic leukaemia were tested for antibodies to Epstein-Barr (EB) virus and to other viruses. The antibody response to the test viruses in these children was unremarkable, with the exception of EB virus, where the presence of complement-fixing antibodies in children tested during the first month of their illness suggested that a higher proportion had previous experience with this virus than was the case in control children. The implications of this observation with regard to leukaemogenesis are discussed.

Syndromes of infectious mononucleosis

Physicians are becoming more aware of the existence and diversity of the infec tious-mononucleosislike responses which patients may develop in certain circum stances. Differentiation and identification call for knowledgable familiarity with these various clinical-hematologic responses.

Latent cytomegalovirus infection in blood donors

Twenty-one out of 32 apparently healthy blood donors aged 21 to 65 years yielded positive complement fixation tests with a cytomegalovirus antigen, at titres ranging from 1:8 to 1:64. Virus was present in leucocyte cultures of fresh peripheral blood of two seropositive subjects from a total of 35 donors examined. Plasma and 48-hour stored blood specimens failed to disclose virus in culture. Viruria could not be demonstrated, and there was no evidence of recent illness in the study group. These findings suggest that subclinical viraemia is not uncommon in blood donors.