gamma Interferon production appears to predict time of recurrence of herpes labialis

Peripheral blood mononuclear cells separated from the blood of 29 volunteers within 3 wk of the onset of recurrent oral herpes labialis spontaneously secreted IFN-gamma (and small amounts of IFN-beta) into the culture medium in varying amounts (mean = 77 U/ml, SE = 17). However, interferon could not be detected in the serum of 10 of these patients tested. In the group as a whole, peak levels of interferon were secreted in vitro at 6 to 20 days after the onset of herpes labialis. Serial studies in eight patients showed peak production in the second or third week, with subsequent decrease to undetectable levels at 6 wk. A strong correlation between peak supernatant interferon level and the time to the next recurrence of herpes labialis in each patient was noted (r = 0.82, p less than 0.0001). Herpes simplex antigen-stimulated mononuclear cell cultures from each patient produced a mixture of IFN-alpha and IFN-gamma. A less marked but still significant correlation was noted between the peak mixed interferon level and the inter-recurrence interval (r = 0.52, p less than 0.005). These results suggest that a recurrent herpes labialis acts as an in vivo stimulus to the induction of IFN-gamma-producing cells that circulate in peripheral blood. The IFN-gamma produced is either a direct determinant of frequency of recurrence of herpes or a quantitative marker for other cellular immune events determining frequency.

gamma Interferon production appears to predict time of recurrence of herpes labialis

Peripheral blood mononuclear cells separated from the blood of 29 volunteers within 3 wk of the onset of recurrent oral herpes labialis spontaneously secreted IFN-gamma (and small amounts of IFN-beta) into the culture medium in varying amounts (mean = 77 U/ml, SE = 17). However, interferon could not be detected in the serum of 10 of these patients tested. In the group as a whole, peak levels of interferon were secreted in vitro at 6 to 20 days after the onset of herpes labialis. Serial studies in eight patients showed peak production in the second or third week, with subsequent decrease to undetectable levels at 6 wk. A strong correlation between peak supernatant interferon level and the time to the next recurrence of herpes labialis in each patient was noted (r = 0.82, p less than 0.0001). Herpes simplex antigen-stimulated mononuclear cell cultures from each patient produced a mixture of IFN-alpha and IFN-gamma. A less marked but still significant correlation was noted between the peak mixed interferon level and the inter-recurrence interval (r = 0.52, p less than 0.005). These results suggest that a recurrent herpes labialis acts as an in vivo stimulus to the induction of IFN-gamma-producing cells that circulate in peripheral blood. The IFN-gamma produced is either a direct determinant of frequency of recurrence of herpes or a quantitative marker for other cellular immune events determining frequency.

Cytology of synovial effusions in epidemic polyarthritis

Examination of synovial fluid in eight patients with epidemic polyarthritis following Ross River virus infection showed cell counts ranging from 1,500 to 13,800 per mm3. Stained smears were notable for a paucity of neutrophils and high proportions of monocytes and vacuolated macrophages, which were further characterised by light and electron microscopy. Ross River virus antigen was detected by specific immunofluorescence in monocytes and macrophages of four cases early in the course of the illness, but intact virus was not identified by electron microscopy or cell culture. No cell-associated C3 component of complement or immunoglobulin of IgM or IgG class was detected in any cell-type. These findings indicate that cell counts and simple smears may be useful in the early diagnosis of suspected epidemic polyarthritis, and provide further information pertinent to the pathogenesis of this disease.

Possible genetic determinants in epidemic polyarthritis caused by Ross River virus infection

HLA D locus-related (DR) antigens and Gm phenotypes were determined in 30 patients with epidemic polyarthritis following Ross River virus (RRV) infection and contrasted with those in comparison series of 119 (DR) and 1220 (Gm) normal subjects. HLA DR7 (46.7% cf. 21.0%) and the heterozygous Gm phenotype a+x+b+ (33.3% cf. 15.3%) were significantly increased in the patients, with relative risks of 3.3 and 2.8 respectively. The occurrence of Gm a+x+b+ was independent of DR7, and conferred a relative risk of 4.3 in DR7-negative patients. Differences found in clinical features, specific lymphocyte proliferative responses and antibody titres did not reach significant levels. The association with DR7 was inversely related to age in residents of an area of moderate endemic risk, and to levels of natural cell-mediated immunity (natural killer cell activity). These correlations point to possible mechanisms by which genetic traits might influence the occurrence or consequence of RRV infection.

Incubation time of epidemic polyarthritis

The incubation time of epidemic polyarthritis was estimated in 20 patients with evidence of Ross River virus infection after spending less than three weeks in areas of risk. The smallest estimate consistent with all cases was a range of seven to nine days.

Epidemic polyarthritis acquired in Fiji

Four cases of epidemic polyarthritis which was acquired in Fiji between April and July of 1979 are described. The manifestations of the illness were similar to those of the disease in Australia. Knowledge of the geographic distribution of this disease can be valuable in diagnosis, but it is likely that its range is not yet fully known.

A study of synovial fluid and cytology in arthritis associated with herpes zoster

A case of herpes zoster complicated by acute arthritis with effusions is described. The white cell count in the synovial fluid was low, with a predominance of neutrophils. The synovium showed superficial deposits of fibrin, slight intimal hyperplasia, and subintimal polymorph infiltration. Varicella virus was not detected by culture or electron microscopy, but varicella antigen was demonstrated in the cytoplasm of macrophages in the effusion. Other findings did not determine whether the antigen had appeared in the joint from circulating immune complexes, or following synovial phagocytosis or proliferation of virus.