Antibodies to human T-lymphotropic virus type-I in patients with tropical spastic paraparesis

10 out of 17 (59%) patients with tropical spastic paraparesis (TSP) had antibodies to human T-lymphotropic virus-I (HTLV-I), as did 5 out of 5 TSP patients with systemic symptoms. Only 13 out of 303 (4%) controls, made up of blood donors, medical personnel, and other neurological patients, had such antibodies. These findings suggest either that HTLV-I is neurotropic or that the virus or a related one contributes to the pathogenesis of TSP.

Evidence for exposure to HTLV-III in Uganda before 1973

Fifty of 75 serum samples collected in the West Nile district of Uganda between August 1972 and July 1973 contained antibodies reactive with human T-cell leukemia (lymphotropic) virus type 3 (HTLV-III; mean titer, 601), while 12 of 75 samples were positive in a similar test for HTLV type 1 (HTLV-1) antibodies (mean titer, 236). The samples were screened by enzyme-linked immunosorbent assay and positive results were confirmed by a newly developed unlabeled antibody-peroxidase procedure with enhanced sensitivity for detection of antibody binding to immunoblots of HTLV-III antigen, demonstrating antibodies to proteins with molecular weights of 24,000, 41,000, and 76,000 in nearly all positive samples. Analysis of titration data indicated enhanced titers of antibody against HTLV-III and HTLV-I when coinfection occurred. The high prevalence and relatively low titers [compared to serum from patients with acquired immune deficiency syndrome (AIDS)] of antibodies recognizing HTLV-III proteins in sera from this population at a time that may predate or coincide with the appearance or spread of the AIDS agent (HTLV-III) suggest that the virus detected may have been a predecessor of HTLV-III or is HTLV-III itself but existing in a population acclimated to its presence. It further suggests an African origin of HTLV-III.

Infectious mononucleosis-like response in common marmosets infected with Epstein-Barr virus

Callithrix jacchus marmosets infected with Epstein-Barr virus (EBV) with or without concurrent treatment with cyclosporin A (CySA) remained healthy. Five marmosets given virus alone developed lymphocytosis and heterophile antibody. Antibody to EBV capsid antigens (VCA) appeared and remained at titers of 1:40-1:80 from 15 weeks onward. Two animals produced antibody to the R component of early antigens (EA) from six weeks onward. Five CySA-treated EBV-infected marmosets showed no increase in total lymphocyte counts; only two developed heterophile antibody. Four developed persistent antibody to the EA-R component. All developed antibody to VCA, and mean titers were higher than in animals given EBV alone. Antibody to VCA also appeared in animals given EBV into Waldeyer's ring. Because these responses to EBV resemble those of humans, C. jacchus may provide a useful model for exploring the potential of cofactors in inducing EBV-associated malignancy.

Cryptogenic fibrosing alveolitis and Epstein-Barr virus: an association?

13 patients with cryptogenic fibrosing alveolitis (CFA) and 12 with interstitial lung disease (ILD) of known cause were studied for their humoral response to herpes simplex virus (HSV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV). Serum antibodies to HSV and CMV were within the normal range in all patients. 10 patients with CFA had raised serum antibodies to EBV, and IgA against viral-capsid antigen (VCA) was detectable in all 13. In the other 12 patients EBV serological profiles were normal and IgA against VCA was detectable in only 1 patient. The EBV antibody levels did not correlate with the level of circulating immune complexes, the presence of rheumatoid factors, or the cytological findings of the alveolitis. The presence of IgG against VCA in 5 CFA patients suggests local production of EBV-specific immunoglobulins. Elevated IgG and IgA against EBV in CFA may indicate non-specific depression of cell-mediated immunity or that EBV plays a part in the aetiology of CFA.

Final case reporting from the Ugandan prospective study of the relationship between EBV and Burkitt's lymphoma

A prospective epidemiological study was carried out in the West Nile District of Uganda from 1972 to 1979 in order to investigate the aetiological role of the Epstein-Barr virus (EBV) in Burkitt's lymphoma (BL). By 1976, fourteen BL cases had been detected among the 42,000 children originally bled in the study area. Testing of sera from BL candidates and neighbourhood controls showed that children who develop BL later have EBV/VCA titres several dilutions higher than their age- and sex-matched neighbours. This appearance of a strong EBV activity long before BL development was taken as evidence of a causal role of EBV in BL. In order to add to the unique material of pre-bled BL cases, BL detection was continued up to March 1979 when field work became impossible in Uganda. Two additional pre-bled BL cases were found during this extension of the study. The serological and virological evaluation of these additional cases showed that the EBV/VCA titres, but not the EA and EBNA titres, were about two dilutions higher in the BL candidates than in the controls. Hybridization assays showed that both lymphomas contained EBV/DNA in the tumour cells. These additional results thus confirm the findings in the first 14 cases and strengthen the epidemiological evidence for a causal role of the EBV in endemic BL.

Enhancement of spontaneous VCA and EA induction in B95-8 cells and EA induction in Raji cells treated with human leukocyte interferon

The purpose of this study was to determine the antiviral effect of human leukocyte interferon on Epstein-Barr virus (EBV) viral capsid antigen (VCA) and early antigen (EA) induction in B95-8 and Raji cells. Interferon made at the Institute of Virology, Beijing, and that provided by Dr. Cantell gave unexpected results. Both interferon preparations markedly enhanced spontaneous VCA and EA induction in B95-8 cells and EA induction in Raji cells simultaneously treated with croton oil and n-butyrate. Interferon treatment alone had no effect on EA induction in Raji cells. Thus, the effect of interferon on EA and VCA induction was related to the type of EBV infection, i.e., productive or latent. The enhancing activity of interferon could only be partially inhibited by retinoid 7901. It is suggested that the mechanism for enhancement of EA induction by interferon is different from that of EA induction in Raji cells by croton oil and n-butyrate.

Detection of Epstein-Barr virus antigens and antibodies by peroxidase-labeled specific immunoglobulins

Detection of the Epstein-Barr (EBV) antigens, early antigen (EA), viral capsid antigen (VCA), and nuclear antigen (EBNA) by the indirect immunoperoxidase technique was highly sensitive. Antibody titers to EBNA, EA, and VCA were determined in more than 25 sera of patients with Burkitt lymphoma (BL), nasopharyngeal carcinoma (NPC), or normal persons. A good correlation between the titers of these antigens was obtained by the immunoperoxidase and immunofluorescence methods. The indirect (anti-IgG) immunoperoxidase technique for the detection of EBNA is, in contrast to the indirect immunofluorescence method, highly sensitive. EBNA was associated with the chromosomes in cells arrested in the metaphase with colchicine.

Superinfection epithelial nasopharyngeal carcinoma cells with Epstein-Barr virus

Attempts were made to superinfect epithelial explant cell cultures prepared from nasopharyngeal carcinomas with Epstein-Barr virus. Virus-specific markers were observed in such cultures 3 days after superinfection. In addition, expression of Epstein-Barr virus early antigens was observed in epithelial cell explant cultures treated with iododeoxyuridine. The results suggest that epithelial cells of at least certain nasopharyngeal carcinomas possess the receptor for the Epstein-Barr virus and that the latent virus genome can be induced from epithelial cells prepared from such tumors.