Comparative evaluation of an immunofluorescent antibody test, enzyme immunoassay and western blot for the detection of HIV-1 antibody.

Screening blood and blood products for human immunodeficiency virus type 1 (HIV-1) antibody is predominantly performed by enzyme immunoassay (EIA), and results must be confirmed by the more immunospecific Western blot (WB) assay. This study evaluated an HIV immunofluorescent antibody (IFA) test relative to WB assay for use in confirming EIA designated HIV-1 antibody-positive sera. Specimens from seroconversion and CDC panels as well as clinical specimens obtained for routine EIA HIV-1 antibody screening were evaluated. Results with 209 specimens indicated that sensitivity and specificity of the Fluorognost-HIV assay were equivalent relative to WB. In addition, the Fluorognost-HIV IFA test was faster and easier to perform than the WB assay, and unlike the WB assay was not prone to indeterminate results.

Experimental congenital disease with simian cytomegalovirus in rhesus monkeys.

Cytomegalovirus (CMV) infections occur worldwide and are responsible for severe damage to the child in from one to five newborns per 20,000 births. Animal models of congenital CMV infection resulting in disease have been developed in mice and guinea pigs. We report here the development of ventricular dilatation and leptomeningitis in rhesus monkeys, Macaca mulatta, following intrauterine infection with rhesus cytomegalovirus (RCMV). Central nervous system (CNS) lesions were associated with low cytomegalovirus fluorescent antibody titers in affected fetuses. In several infected animals, RCMV was isolated at necropsy from neural and nonneural tissues taken shortly after birth. This model allows investigators to study the pathogenesis and prevention of CNS changes following RCMV infection.

Brain tumors of owl monkeys inoculated with JC virus contain the JC virus genome.

The DNA from astrocytomas that developed in adult owl monkeys 16 to 36 months after intracranial inoculation with JC virus (JCV) was examined for the presence of the JCV genome by hybridization to cloned JCV DNA. The JCV genome was found to be integrated into the cellular DNA in all tumors examined. There was no JCV DNA in normal, uninvolved brain tissue from the same animals. Integration of the genome occurred at a limited number of sites in the cellular DNAs, indicating a clonal origin for the tumors, but none of the tumors had integration sites in common. In all but one of the tumors, there was tandem, head-to-tail integration of two or more copies of the JC genome. In a tumor which had only one integration site and could be analyzed more extensively, there appeared to be a complete copy of the JCV genome present, although deletions of small portions of the genome would not have been detected.

Oligoclonal IgG in CSF of patients with African Burkitt's lymphoma.

Oligoclonal IgG bands were detected in CSF from 12 of 13 patients with African Burkitt's lymphoma (BL) who exhibited neurologic signs or symptoms of CNS involvement. Twenty-three of 26 patients free of neurologic involvement with this tumor were found to lack the oligoclonal IgG bands in their CSF. None of six patients with non-BL included in this study had these bands in their CSF. None of six patients with non-BL included in this study had these bands in their CSF samples. These findings suggest that detection of these bands may be a useful adjunct for determining the presence of African BL that invades the CNS.

Viral-induced astrocytomas in squirrel monkeys.

Saimiri sciureus, the squirrel monkey, is susceptible to the oncogenic effects of JCV following intracerebral inoculation. As in owl monkeys, tumor development follows an incubation time of 14 to 30 months. Four of six virus-inoculated monkeys developed cerebral tumors, three of which were astrocytomas grade 4 and the remaining tumor was a poorly differentiated astrocytoma. All tumors showed high cellularity, mitotic figures, and cellular pleomorphism. In the astrocytoma grade 4, neovascularization was a prominent feature. The blood vessels in the poorly differentiated astrocytoma appeared normal. Multinucleated giant cells were present in all four astrocytomas. Antemortem hemorrhage was seen in one astrocytoma grade 4. Other tumor types were not seen. The occurrence of astrocytomas in a second species of New World monkeys confirms the oncogenicity of JCV for nonhuman primates.

Antibody responses to JC virus-associated antigens by tumor-bearing owl monkeys.

Antibody responses to JCV viral and T antigens were determined in owl monkeys following infection with JCV. Antibody to JCV virion antigen was present in all inoculated monkeys, arising within one months. These antibodies gradually diminished in all nontumor-bearing monkeys and in 10/13 tumor-bearing monkeys over the ensuing 12 months. Antibody to T antigen became evident later in most inoculated monkeys but had a marked variable course and did not correlate well with tumor production. The antibody patterns suggest that JCV is basically nonpermissive in owl monkeys and that the viral genome is retained in a prolonged persistent stage before progressing rapidly into a tumor.

The detection of JC viral genome in owl monkey tumors.

The JC viral genome is integrated into the cellular DNA of brain tumors from owl monkeys inoculated intracranially with JC virus 16-36 months prior to the development of the tumors. Normal brain tissue of the animals did not contain the viral genome. For at least two tumors, restriction endonuclease analysis of the tumor DNA indicates that there is a complete copy of the viral genome present. Integration of the genome in all but one of the tumors was at only one or only a limited number of sites, indicating a clonal origin for the tumors. In all but one of the tumors, there was tandem, head-to-tail integration of two or more copies of the JC genomes.

Cerebrospinal fluid markers in African Burkitt's lymphoma with central nervous system involvement.

Several cerebrospinal fluid markers were found to be elevated in Burkitt's lymphoma patients with central nervous system (CNS) involvement. Antibody levels to the virus capsid antigen of the Epstein-Barr virus and to the brain cell antigens myelin and cerebroside were elevated during active CNS disease. Immune complexes were present in levels above 100 micrograms/ml in most patients with CNS involvement but tended to be low or negative in patients without CNS disease. Oligoclonal IgG bands were present in 12 of 13 patients with CNS disease and in only 3 of 26 patients with no clinical evidence of disease. None of these markers were present in 6 other tumor patients without CNS disease. The presence of these markers in 12 of 13 patients in whom CNS disease was involved suggests that these markers may be useful in determining the status of the tumor with regard to involvement of the CNS.

Amyl nitrite may alter T lymphocytes in homosexual men.

To evaluate the recent outbreak of Kaposi's sarcoma (KS) and opportunistic infections in homosexual men, clinical, virological, and immunological data on two homosexual men with KS and on fifteen healthy homosexual volunteers were collected. Both KS patients had regularly used amyl or butyl nitrite (AN); they had low helper/suppressor (H/S) T-lymphocyte ratios before chemotherapy and high titres of antibody against cytomegalovirus (CMV). Eight of the fifteen volunteers were regular AN users; seven of the eight had low H/S ratios due to larger than normal numbers of OKT8-positive suppressor cells and smaller numbers of OKT4-positive helper cells. In all eight AN users the fluorescence profile obtained with monoclonal antibody 9.6 (which detects the sheep E-rosette receptor) was bimodal, indicating a subpopulation of T cells with increased receptor density. A similar pattern was observed when OKT8, the antibody which detects cytotoxic suppressor cells, was used. Two of the seven men who did not use AN had abnormal fluorescence with reagent 9.6, and one of these also had a low H/S ratio. CMV-antibody titres were persistently high in fourteen of the fifteen healthy men, but the titres were not related to AN use of T-cell abnormalities. The data suggest that nitrites may be immunosuppressive in the setting of repeated viral antigenic stimulation and may contribute to the high frequency of DS and opportunistic infections in homosexual men.

Management of genital herpes simplex virus infection during pregnancy.

The clinical course and outcome of 58 pregnancies in 57 women with culture-verified genital herpes simplex virus (HSV) infection during gestation are reported. In 19 cases (33%) an active genital HSV infection was present within 1 week of delivery. Of the 60 infants delivered, 58 survived. No maternal or perinatal morbidity or mortality was attributable to HSV. This experience suggests that weekly culturing of the cervix and all other previously infected genital sites from the 36th week of gestation until delivery is an acceptable plan for managing such pregnancies. Women without evidence of infection at the onset of labor can be allowed to deliver vaginally. With appropriate precautions, breast-feeding by mothers with genital HSV infections is not contraindicated.

Suppressor cell activity in multiple sclerosis.

Patients with multiple sclerosis and matched controls were tested for lymphocyte stimulation response and induction of suppressor cell activity in response to concanavalin A (Con A) and antigens from axolemma or myelin. Of 17 stable patients, 6 failed to have a suppressor cell response activated by one of these brain cell antigens. Among the patients who lacked these suppressor responses, five had lymphocyte stimulation responses to the same antigens. All matched controls except for one had suppressor cell responses to these antigens and none responded with a positive cellular immune reaction. We found no difference in lymphoproliferative responses to Con A in patients and controls. The level of suppressor cell activity induced by Con A in the stable MS patients varied but did not differ significantly from that of controls.

Coronavirus antibodies in sera from patients with multiple sclerosis and matched controls.

Sera from patients with multiple sclerosis and carefully matched controls were tested for antibodies to three strains of coronavirus. There was no significant difference in the levels of antibody in the patients vs the controls. We conclude that unless the strains of coronaviruses recently reported to have been isolated from patients with multiple sclerosis express important serological differences from those used in these studies, coronaviruses are not associated with the cause of multiple sclerosis.

Tumor promoting agent induces lymphocyte mitogenic factor.

Human peripheral mononuclear cells treated with tumor promoting agent, 12-O-tetradecanoyl phorbol 13-acetate (TPA), released a soluble lymphocyte mitogenic factor (MF). The MF was found to be a protein capable of eliciting a proliferative response in normal human lymphocytes within 40-46 hours. The MF was detected in the culture supernatant fluid as early as 12 hours after TPA treatment and reached maximum at 48 hours. The biochemical characterization of MF is under active investigation.

Measles and canine distemper antibody. Presence in sera from patients with multiple sclerosis and matched control subjects.

Antibody to measles virus and canine distemper virus (CDV) was demonstrated in sera from patients with multiple sclerosis (MS) and from carefully matched control subjects. Elevated measles and CDV antibody titers were found in patients with MS when compared with the matched control subjects. The correlation between the measles and CDV antibody titers was quite high, suggesting that the antibody levels between the two viruses are very closely related. Based on the results of our study and a review of the literature, our conclusion is that the CDV antibody levels in patients with MS and matched control subjects are associated with occurrence of measles virus antibodies.

Scanning and transmission electron microscopy study of antibody-dependent lymphocyte-mediated cytotoxicity on measles virus-infected cells.

The structural events related to antibody-dependent lymphocyte-mediated cytotoxicity (ADLC) have been studied on measles virus-infected cells using human peripheral blood lymphocytes (PBL) and anti-measles virus serum. The first event in ADLC was a recognition process occurring with 15 min after contact between the infected cells and lymphocytes. Plasma membrane and microvilli of adsorbed PBL were specifically attached to virus-induced ridges over nucleocapsids and to viral buds. After 30 min, a fraction of adsorbed PBL (K cells) changed shape and extended long filipodia toward the target cells which, in turn, showed long villi contacting the PBL. At 4 h, when cytotoxicity as measured by chromium release was maximum, K cells had flattened and numerous blebs and ruffles formed on their surface. The K-cell alterations varied in intensity with the type of measles-infected target cell, but frequently the K cells appeared irreversibly damaged. T- and non-T-cell fractions were separated, and in situ erythrocyte rosettes were used as markers for subpopulations which were easily recognized by scanning electron microscopy. Most of the cytotoxic K cells were identified as non-T cells carrying Fc receptors for immunoglobulin G. However, a small subpopulation of cells bearing both sheep erythrocyte and Fc receptors was also found to be involved in ADLC by chromium release assay as well as by electron microscopy. Some of these interacting T cells extended a long uropod on the target cell, but their intracellular structure remained unaltered through ADLC, in contrast with the other T cells and the non-t killer cells. This suggests that perhaps some T killer cells might remain functional after the cytotoxic interaction with a target cell.