Ten sporadic cases of venereal spirochaetosis, caused by Treponema paraluis-cuniculi, were seen in New Zealand white rabbits in two years. An equal number of males and females were affected. Females tended to have milder clinical signs than males. Lesions were usually found on the prepuce in males and the vulva in females, although the anus and skin of the perineum were also affected. Facial lesions were rare. Lesions healed in seven to 28 days in rabbits treated with penicillin. Eight rabbits had antibodies reactive in the Venereal Disease Research Laboratory (VDRL), rapid plasma reagin (RPR), and fluorescent treponemal antibody absorbed (FTA-ABS) tests when the disease was first diagnosed. In several rabbits followed longitudinally, RPR test results became negative two to four months after antimicrobial treatment, VDRL antibody titres diminished but usually persisted at low levels, while FTA-ABS antibodies declined slowly and were still evident 12 months after treatment.
Twenty five homosexual men from London, 14 of whom had persistent lymphadenopathy and 11 of whom did not, were tested for immunity to Epstein-Barr (EB) virus. All yielded positive results to serological tests for the viral capsid antibody, and 11 had antibodies to the early antigen. Thirteen out of 17 were excreting virus into the saliva; culture of peripheral blood mononuclear cells from two of these patients showed no detectable regression induced by T cells that was specific to EB virus. No differences were found between the patients with and without lymphadenopathy. Peripheral blood B cells from six patients with hypergammaglobulinaemia were double stained for cytoplasmic immunoglobulin and EB viral nuclear antigen, and in all cases the activated B cells producing immunoglobulin did not contain EB nuclear antigen. Similarly, lymph node biopsy specimens from five patients showed no cells with EB nuclear antigen. These results indicate that although homosexual men have a high incidence of reactivated infection with EB virus, this viral infection is not the cause of the polyclonal activation of B cells seen in peripheral blood and is not implicated in the aetiology of the lymphadenopathy found in these men.
An enzyme linked immunosorbent assay (ELISA) for detecting antibody to antigenic Trichomonas vaginalis macromolecules has been identified using whole cells or an aqueous protein extract as antigen. The test was developed under optimum conditions using serum samples from experimental animals. The sensitivity of the ELISA was equal to or greater than that obtained by radioimmunoprecipitation and electrophoresis-fluorography techniques. The ELISA was capable of assessing antibody responses during the development of lesions in animals inoculated subcutaneously and it reproducibly measured the individual classes immunoglobulins directed at T vaginalis. The colorimetric assay was also suitable for showing cross reactivity between trichomonal species as well as between different strains of T vaginalis. Conditions established for monitoring antibody to trichomanads in immunised rabbits or infected mice were equally effective for human materials, such as serum or vaginal washes. Serum from experimental animals or infected people showed high concentrations of IgG, IgA, and IgM antibody to trichomonads. Only antibodies of the IgG and IgA class were detected in vaginal washes from women with acute trichomoniasis. No IgE antibody to trichomonads was found under a variety of conditions in serum samples from patients or experimental animals.
A total of 83 male homosexuals were studied to ascertain the carriage of intestinal protozoal cysts. The homosexual group had a significantly (p less than 0.0005) higher prevalence than a control group. One or more types of protozoa were found in 33 homosexuals. The carriage of intestinal protozoal cysts was associated with particular sexual practices and promiscuity, but not with symptomatic bowel disorders. The possible implications of the carriage of these cysts are discussed.