Western blot analysis of serological response in Helicobacter pylori in acid peptic diseases.

A prospective study was undertaken in 70 patients presenting with acid peptic disease with the objective of characterising the serological response to Helicobacter pylori and finding antigens specific for the serodiagnosis of H. pylori infection. H. pylori status was assessed by smear microscopy, rapid urease activity, culture and histopathology of endoscopic gastric antral biopsy specimens. Serological characterisation was carried out by using western blotting of various antigenic components of H. pylori and subsequent enzymatic detection of antibodies against them. Four reactive bands in the molecular weight range of 45-65 kDa were present in all subjects irrespective of H. pylori status. Four to six immunoreactive bands in the molecular weight range of 21-45 kDa were found only in patients with positive H. pylori status and histopathologically proven gastritis. These immunoreactive components may be valuable in specific immunodiagnosis of H. pylori infection.

Strategies for purification of four reproductive hormones from the same batch of buffalo (Bubalus bubalis) pituitaries.

The occurrence of different reproductive hormones like LH, FSH, TSH and prolactin, in different side fractions obtained during the extraction of buffalo pituitary glands either by the procedure of Papkoff et al. [Arch Biochem Biophys, 111 (1965) 431] or by that of Ellis [Endocrinology, 69 (1961) 554], was examined with the aid of antisera to respective heterologous hormones as well as bio-assays. Thus in the procedure of Papkoff et al., the SP-Sephadex fractions could be taken for purification of LH and TSH, while the acid pellet yielded prolactin. Further it was shown that 50% (NH4)2SO4 could be directly size fractionated and following cation exchange chromatography yields LH and TSH. FSH could be purified from 80% ammonium sulphate pellet. In another protocol of Ellis, differential extraction and chromatographic separation yielded all the four reproductive hormones. Some of the physico-chemical and immunobiological characteristics of these hormones are described.

Enzyme linked immunosorbent assay & indirect fluorescence assay for rapid diagnosis of Bacteroides fragilis infections.

Antibodies for B. fragilis (NCTC 9343) were detected in sera of 121 patients and 37 controls using four methods viz., enzyme linked immunosorbent assay (ELISA), indirect fluorescence test (JFA), countercurrent immunoelectrophoresis (CIE) and indirect haemagglutination test (IHA). Of 121 patients, 57 were culture positive for B. fragilis, 38 positive for anaerobes other than B. fragilis and 26 were negative for anaerobes. In the B. fragilis culture positive group, antibodies to B. fragilis were positive in 82.5, 84.2, 85.90 and 91.2 per cent patients by CIE, ELISA, IHA and IFA respectively. In B. fragilis positive patients IFA was more sensitive than IHA, which for other groups IHA was found to be more sensitive than IFA. When all groups were taken together IHA was found more sensitive than IFA. ELISA and IFA tests are recommended for rapid serological diagnosis of B. fragilis infections, where facilities for these tests are not available, CIE and IHA could be done. Cross reactivity with other Gram negative anaerobic and aerobic bacteria should be kept in mind since seropositivity varied for B. fragilis (82-91%). In infections with microbes other than B. fragilis seropositivity varied between 23.7 to 63.2 per cent and in patients having cultures sterile or positive for other organisms seropositivity was 30.8 to 42.3 per cent. This nonspecificity could be due to other antigens that cross react between B. fragilis and other anaerobes and aerobes or the use of an antigen lacking high purity.