1/4. 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.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/4. antibodies to an Epstein-Barr virus nuclear antigen synthetic peptide in infectious mononucleosis. Report of two cases.The Epstein-Barr virus nuclear antigen (EBNA-1) contains a region of repeating glycine and alanine amino acids. It has been shown that this region contains a major epitope of EBNA-1. With well-characterized sequential sera from two cases of acute infectious mononucleosis, a specific IgM response was detected to the EBNA-1 synthetic peptide by enzyme-linked immunosorbent assay (ELISA). Conversely, an IgG response was observed in the convalescent phase of the illness with a progressive decline of the IgM antibodies. This response was observed with heterophil-positive and heterophil-negative EBV/IM. The peptide-specific serologic response was confirmed by immunoblotting, the serial serum samples on extracts of EBV transformed B-cells. There was excellent correlation between the antipeptide ELISA and blotting techniques.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/4. Variant strain of propionibacterium acnes: a clue to the aetiology of Kawasaki disease.By means of anaerobic culture for 3-4 weeks a variant strain of propionibacterium acnes was isolated from one lymph-node biopsy specimen, and from blood samples of five of twenty-three patients with early Kawasaki disease, but from only one of fifteen blood samples from patients after 8 days' illness. No anaerobe was isolated from sixty age-matched controls with various disorders, but the same bacillus with the same serotype was isolated from house-dust mites from six patients' homes. patients had significantly higher serum agglutination titres to these strains than controls. The antigen moiety of P acnes was found in the patients' circulating immune complexes. Inoculation of animals caused various inflammatory lesions, particularly in the reticuloendothelial system, and coronary arteritis, myocarditis, and endocarditis in one of them, suggesting that the bacillus is pathogenic. The culture filtrate of this strain showed toxicity in tissue culture. This variant strain of P acnes may have a causative role in Kawasaki disease and house-dust mites a role as vectors.- - - - - - - - - - ranking = 0.2keywords = antigen (Clic here for more details about this article) |
4/4. Virologic, immunologic, and clinical observations on a patient during the incubation, acute, and convalescent phases of infectious mononucleosis.One patient with infectious mononucleosis (IM) was studied from the probable time of Epstein-Barr virus (EBV) infection (38 days before the onset of clinically overt disease), during the incubation and acute phases, until 6 months after clinical remission. Analysis of spontaneous outgrowth of EBV-carrying lymphoblastoid cells, by limiting dilution on feeder layer cultures, showed that virus containing B lymphocytes are already present early during the incubation period. Also low interferon serum levels were detected early after infection, and only before the onset of clinical disease. All other studied clinical laboratory and virus-associated variables were within normal range during the incubation phase, but changed to a pattern characteristic of IM in parallel to the clinical symptoms. During the acute disease EBV-associated nuclear antigen (EBNA)-positive cells could be directly detected among the lymphocytes, and antibodies to EBV antigens appeared. lymphocytes stained by monoclonal antibodies, detecting Ia-like determinants (activated cells) and suppressor cells, increased dramatically, in parallel to a strong increase of functional suppressor cell activity, measured by inhibition of blastogenesis and PWM-induced immunoglobulin production. During the acute phase there was also a decrease of spontaneous cytotoxicity against the NK-sensitive cell line K562, while cytotoxicity (spontaneous) against an autologous EBV-positive lymphoblastoid cell line (LCL) was detected only during this phase. These reactions correlated to the presence of blasts, and the autologous reaction was exerted mainly by Fc-receptor-negative cells. Lymphokine production in response to EBV antigens was also initiated during the acute phase. During the convalescence period the serological and cellular immune parameters adjusted to the pattern of a normal EBV-seropositive person.- - - - - - - - - - ranking = 0.6keywords = antigen (Clic here for more details about this article) |