Changes in Borrelia burgdorferi-specific serum IgG antibody levels in patients treated for acrodermatitis chronica atrophicans.

The kinetics of Borrelia burgdorferi-specific serum IgG antibody values in 74 patients treated for acrodermatitis chronica atrophicans was analysed by means of enzyme-linked immunosorbent assay. At the last clinical control, there had been no clinical signs of active infection. The serological follow-up time ranged from 12 months to 5 1/2 years (median 2 years and 1 month). In 68 (92%) of the 74 patients, a significant decrease of the specific antibody values was found within 3 years after the initiation of therapy. In 53 (72%) of the patients, this decrease was found within 15 months. Most of the patients remained seropositive during the follow-up period. The results show that a significant decline of the levels of serum IgG antibodies to Borrelia burgdorferi can be expected in the majority of patients who do not exhibit clinical evidence of persistent infection after antibiotic treatment of acrodermatitis chronica atrophicans.

Comparison of four different serological methods for detection of antibodies to Borrelia burgdorferi in erythema migrans.

Three different enzyme-linked immunosorbent assays (ELISA) and Western blot were compared in regard to the detection of antibodies to Borrelia burgdorferi in sera from 100 patients with erythema migrans and from 100 controls. For IgG detection, a commercial indirect ELISA kit with flagellum antigen (flagellum ELISA) was significantly more sensitive than the routinely-used indirect ELISA with sonicated whole-cell antigen (sonicate ELISA) (p = 0.008). The difference in positivity in the IgM test was of borderline significance (p = 0.058). An IgM antibody-capture ELISA with sonicated whole-cell antigen (capture ELISA) was significantly more sensitive than either the IgM sonicate ELISA (p less than 0.001) or IgM flagellum ELISA (p less than 0.001). With the Western blot pattern chosen as the criterion for positivity, IgM Western blot was at least equal to IgM capture ELISA in terms of the number of positive erythema migrans sera, but a frequent discrepancy between these two tests was noted as to positivity in individual sera. IgG Western blot was considered to be of less value for the diagnosis of current disease due to a high occurrence of positivity among controls.

Influence of interferon on antibody production and viability of malignant cells from patients with multiple myeloma.

The influence of interferon (IFN) on antibody production and viability of malignant cells from patients with multiple myeloma was evaluated. Following incubation of bone marrow cells with IFN-alpha (5000 units/ml) for 7 days) a decreased production of monoclonal immunoglobin (mlg) was detected in all experiments except one. IFN induced a greater than 50% decrease in myeloma cell viability in 11 patients and a greater than or equal to 25% decrease in 4 patients, whereas in myeloma cells from 8 patients IFN had no or only minor effects. The observed effect was not due to an inhibition of proliferation since less than 5% of the myeloma cells were labeled with [3H]-thymidine during 7 d of culture. There was no statistically significant correlation between decreases in myeloma cell viability and effects on mlg production, exemplified by the fact that mlg production was decreased also in patients showing no sensitivity to IFN's cytotoxic action. Depletion of autologous T-cells, NK-cells and/or monocytes did not abrogate the effects observed. We conclude that IFN can reduce the viability of myeloma cells and the production of Ig from these cells and that the latter can be exerted without an antitumor effect.

ELISA-determined serological reactivity against purified trichophytin in dermatophytosis.

Serological activity in 62 patients wih dermatophytosis was investigated using purified trichophytin preparation as antigen (produced by the ethylene glycol method). Antibodies of IgG and IgM classes were determined by means of ef enzyme linked immunosorbent assay (ELISA). In comparison with 79 controls consisting of groups of healthy blood donors and dermatological outpatients, the dermatophyte-infected patients showed a significantly higher mean IgG response to trichophytin antigen preparation. On the other hand several individual cases were low responders. In a group of 10 control children, no IgG activity against trichophytin could be demonstrated. IgM class antibodies showed no significant differences between the groups investigated. These findings indicate that differences in the amounts of antibodies of IgG class against trichophytin as measured by the ELISA method reflect differences in the degree of mycotic sensitization between groups of individuals having experienced varying degrees of exposure to dermatophytes. Nevertheless, the determination of IgG antibodies in dermatophytosis seems to be of limited clinical value.