Article
Phenotypic study of peripheral blood lymphocytes and humoral immune response in Helicobacter pylori infection according to age
Registro en:
SOARES, Taciana de Figueiredo et al. Phenotypic study of peripheral blood lymphocytes and humoral immune response in Helicobacter pylori infection according to age. Scand J Immunol., v. 62, n. 1, p. 63-70, July 2005.
0300-9475
10.1111/j.1365-3083.2005.01638.x
Autor
Soares, Taciana de Figueiredo
Rocha, Gifone Aguiar
Rocha, Andreia Maria Camargos
Oliveira, Celso Afonso de
Queiroz, Dulciene Maria de Magalhães
Oliveira, Rodrigo Correa de
Martins Filho, Olindo Assis
Carvalho, Anfrisina Sales Teles de
Bittencourt, Paulo Fernando Souto
Faria, Ana Maria Caetano de
Resumen
There are differences between children and adults in certain aspects of the Helicobacter pylori (HP) infection, among them the lower titre of IgG antibodies anti-HP in the former group. Thus, we investigated by means of flow cytometry CD4+/CD3+ (CD4+T), CD8+/CD3+ (CD8+T) and CD19+/CD3- (B) cells, activation/co-stimulatory markers (CD4+/HLA-DR+, CD4+/CD28+, CD8+/HLA-DR+ and CD8+/CD28+) and by means of ELISA IgG anti-HP antibodies in the peripheral blood from HP-positive and -negative children and adults. An increased CD4+/CD28+ and CD8+/CD28+ percentage and number of CD4+/CD3+ cells were seen in infected adults. Conversely, no difference was observed between infected and noninfected children, but when they were stratified by age, an increased CD4+/CD28+ cell percentage was seen in the HP-positive group older than 10 years. The mean level of IgG anti-HP was lower in younger infected children, increased with age and correlated with CD4+ cells. Our data suggest that the immune response to HP infection vary according to the age. Low percentage of activated CD4+ cell may contribute to the lower level of serum IgG anti-HP observed in younger infected children. In addition, the CD4+ cell participation during the infection seems to begin after 10 years old, when the immune response becomes similar to that seen in adults.