[IgG and IgA immunoglobulins in helicobacter pylori infections of children with chronic dyspepsia before and after two week triple drug therapy]. / Immunoglobuliny IgG i IgA w zakazeniach Helicobacter pylori dzieci z przewlekla dyspepsja przed i po dwutygodniowej trójlekowej terapii.

The aim of this study was to investigate whether serological techniques, ELISA and Western blot, are useful in monitoring treatment of H. pylori-associated chronic dyspeptic symptoms in children. We observed a correlation between a decrease in the anti-H. pylori IgG titer and an effective treatment. So, our results suggested that the ELISA assay conducted with a glycine H. pylori extract can be a good noninvasive assay for monitoring the effectiveness of the therapy. By using the Western blot method, we showed some variation in the specificity of anti-H. pylori IgG produced before and after treatment. However, this variation was not correlated with the effectiveness of the therapy.

Systemic humoral response to Helicobacter pylori in children and adults.

In this study we compared the development of anti-H. pylori humoral response in adults and children. Two antigens: H. pylori acid glycine extract (GE) and recombinant cagA were used for ELISA and Western blot. Anti-GE IgG were detected in all and anti-cagA IgG in about 50% of H. pylori infected adults and children. The prevalence of anti-GE and anti-cagA IgG in the sera from H. pylori-uninfected children with gastritis/gastroduodenitis was lower than in the sera from healthy adult blood donors. Serum IgA were demonstrated for 71% of H. pylori-infected adults and for a smaller proportion (about 30%) of uninfected adult patients or normal subjects. Such antibodies were detected neither for infected nor for uninfected children. There was an evident difference between the proteins of H. pylori glycine extract recognized by antibodies present in the sera from H. pylori-infected children and adults. The antigen of molecular weight over 107 kDa was recognized exclusively by the sera from 30% of H. pylori-infected adults. The 80-107 kDa bands were recognized more frequently by the sera from adults than from children. In contrast, sera from infected children more frequently than sera from infected adults reacted with the bands of 14 kDa, 19 kDa and 26 kDa. The H. pylori antigens recognized by IgG, produced by infected children and adult patients, should be taken into consideration in the developing of tests for serodiagnosis of H. pylori infection.

Serum IgG antibodies in children and adults reacting with Helicobacter pylori lipopolysaccharides.

The presence of IgG antibodies reacting with Helicobacter pylori lipopolysaccharides (LPSs) in sera from children and adults diagnosed as H. pylori-infected, as well as healthy persons, was tested. There was no correlation between the production of antibodies reacting with H. pylori surface proteins and LPSs. Also no correlation between reactivity of tested sera with H. pylori antigens and deep rough mutant (Re types) enterobacterial LPSs was revealed. The prevalence of anti-LPS IgG in randomly selected children was relatively high.

Attachment of Helicobacter pylori strains to human epithelial cells.

The aim of the study was to characterize several clinical isolates of H. pylori as regards the activity and specificity of their haemagglutinins and the involvement of surface sialic acid-specific and heparin-binding compounds in the adhesin of the bacteria to human epithelial cell lines. Although H. pylori strains caused haemagglutination (HA) of sheep erythrocytes, they differed markedly by activity and specificity. On the basis of haemagglutination inhibition study three types of H. pylori strains could be distinguished. The HA of Type I strains was inhibited with fetuin/mucin but not asialofetuin/asialomucin. The HA activity of Type II strains was inhibited with fetuin/mucin and asialofetuin/asialomucin. The HA of Type III strains was not influenced by any of these inhibitors. In vitro, H. pylori strains bound to the cells of human epithelial lines: HeLa, Kato-3, Ags. However, various compounds mediated the binding of H. pylori types distinguished by HA, to epithelial cells. The interaction of some of H. pylori strains with epithelial cells was mediated by bacterial sialic acid-binding compounds. The majority of H. pylori strains used heparin-binding surface compounds to attach to epithelial cells. Clinical H. pylori strains differ by the compounds used in adhesin to epithelial cell lines, however, this process also depends on the expression of appropriate receptors on the host cells.

[Progress in diagnosis of infections brought on by Helicobacter pylori]. / Postepy w diagnostyce zakazen wywolywanych przez paleczki Helicobacter pylori.

A wide range of techniques was developed for identification of Helicobacter pylori, since the association of the microorganism with gastritis and peptic ulcer has been established in 1983. Up to now, isolation and identification of H. pylori from the gastric biopsy, remains the standard diagnostic procedure. However, attention is focused on rapid non-invasive tests, for monitoring the infection, such as urea breath test. Serological methods as ELISA and Western blot are suitable for estimation of specific anti-H. pylori local and systemic humoral response. Molecular tests based on PCR reaction allow the detection of H. pylori in biopsy specimens and recently in other clinical samples as saliva or faeces. They are also very promising in epidemiological studies.