Serological studies of Australia-antigenaemia in different categories of sick and healthy persons.

Sera (1,333) were collected from patients at various days after the onset of manifest B-virus hepatitis; from long term asymptomatic carriers of Au-antigen, with or without a demonstrable history of hepatitis; and from apparently healthy Au-negative persons. Au-anti-genaemia was tested with gel-diffusion (GD), counter immunoelectrophoresis (CIE), reversed haemagglutination (RHA) and complement fixation (CF). The CF test was found to be as sensitive as the RHA test, about 10 times more sensitive than the CIE, and about 25 times more sensitive than the GD test. With greater amounts of antibodies used in CF tests, the titres of AU-antigen were higher and the heights of prozones were lower. It is stressed that in screening for Au-antigen, sera should be tested in dilutions from 2 to 64, against 4 to 8 CF units of antibody. The frequency of asymptomatic long term Au-carriers, in the group with a known history of hepatitis, amounted to 41%, and themean titre of Au-antigen was 1:392. In the group of long-term carriers with no detectable history of hepatitis, the rate of Au-carriers was 1.6%, and the mean titre was 1:19.

[Interferon alpha in the treatment of prolonged hepatitis A virus infection]. / Interferon alfa u lecenju protrahovane infekcije virusom hepatitisa A.

Hepatitis A viral infection usually lasts up to 12 weeks, but in 3-16% of patients relapses may occur and the course of the disease is protracted. The outcome of hepatitis A is always good, so that antiviral therapy is not necessary. However, from the aspect of patients with protracted course of the disease up to a year, it might be important to restore clinical recovery in a shorter period of time. Knowing about antiviral and immunomodulatory effects of endogenous interferon (virally activated) in treatment of protracted hepatitis A, we introduced interferon-alpha in the 12th week of the disease and followed-up its effects on the further course of the disease. The study comprised 80 patients with established diagnosis of acute protracted hepatitis A, excluding hepatitis B, Epstein-Barr, cytomegalovirus, adenovirus or toxic liver lesion. In 40 patients treated with interferon we followed up the activity of aminotransferases and persistence of IgM-anti-HAV in correlation with the same parameters in 40 patients treated symptomatically. The registered persistence of aminotransferases' pathological activity was 20:30 weeks (interferon: symptomatic therapy). In greater doses interferon affected the length of persistence IgM-anti-HAV, 20:34 weeks (interferon: symptomatic therapy).

A virological study of post-vaccinal encephalitis.

In the province of Voyvodina 18 cases of post-vaccinal encephalitis have been recorded, three of which were fatal.The estimated morbidity rate was 0.6 per 10(5) after revaccination, and 3.9 per 10(5) after primary vaccination. The virological studies described, as well as other findings referred to in this report, are consistent with the possibility of an autoimmune aetiology of the post-vaccinal encephalitis cases observed.

Skin reactivity and antibody response following vaccination against smallpox.

Revaccination between 2 and 5 years after the last vaccination induced higher complement-fixation titres than revaccination 7-63 years after the last vaccination. The highest CF titres were reached during the 3rd to the 5th week after vaccination.Fifty-two serum samples, taken 137 or more days after a successful vaccination, all showed CF titres lower than 1/2.In a group of successfully vaccinated persons with no post-vaccinal complications, 65 out of 66 had a successful ;take' after one or two subsequent vaccinations.Sera of persons receiving primary vaccination showed significantly lower CF titres than sera of revaccinated persons. Cases of post-vaccinal encephalitis showed greater antibody response than uncomplicated successfully vaccinated cases in both the primary vaccination and revaccination groups. The antibody response in revaccinated persons with post-vaccinal encephalitis was greater than that in the group of successfully revaccinated cases without encephalitis.A group of 26 naturally hyporeactive persons completely failed to ;take' even after vaccination repeated between 3 and 10 times (average 5 times per person). The frequency of seropositives in this group, and the height of their CF titres, were significantly lower than in the group of successfully vaccinated persons. These findings support the view that untreated persons who repeatedly fail to ;take' with the vaccine must not be considered immune.In vaccinated persons treated with immunoglobulin (with or without simultaneous treatment with Marboran) antibody production was apparently diminished. Treatment of patients with Marboran significantly lowers the capacity of the vaccine to ;take'.

Evaluation of assay methods for hepatitis B surface (HBsAg) antigen and its antibody (anti-HBs) in viral hepatitis B (VHB)-HBsAg-positive.

The sensitivity of methods for the detection of HBsAg and its anti-HBs was compared in serial 1200 sera samples from 30 patients with VHB-HBsAg-positive. HBsAg was tested by gel-diffusion (GD), counter-immunoelectrophoresis (CIE), reversed haemogglutination (rHA), redioimmunoassay (RIA), and enzyme immunoassay (EIA). RIA and EIA methods are statistically significantly more sensitive compared with the other methods (P less than 0.0005). By these methods the minimal concentrations of HBsAg in sera can be proved. Although there is no statistically significant difference in the sensitivity between RIA and EIA, the latter is more sensitive if the subtype ay-HBsAg is considered (12 sera samples). In 24 patients the subtype was ay, in two ad, and in four it could not be differentiated. In 70% of patients anti-HBs was proved by RIA and in 10% by CIE, i.e., in 73% and 9% of sera samples, respectively. In 117 sera samples of these patients the sensitivity of RIA and EIA was compared for determination of anti-HBs. No statistically significant difference between the methods for determination of anti-HBs was found (50.42%: 40.17%). No immune response to HBsAg has been observed in 9 cases, but 6 of them have remained permanent carriers of this antigen.

Variation of the HL-A antigens during neoplasm evolution.

The study deals with the tissue antigen frequency in a group of 1648 patients with different clinical forms of cancer, hospitalized in the Oncological Institute, Bucharest. The authors do not find a correlation between a tissue antigen predominance and the occurrence or development of a certain form of cancer. Nevertheless a loss of some tissue antigens was noticed in severe advanced cases with multiple metastases. This fact can be observed also in patients irradiated during serotypings or treated with cortisone. At least 5 weeks after irradiation or in patients with favourable response to the treatment, with temporary important remission, the recurrence of the histocompatibility antigens can be obtained in subsequent examinations.