ESPE Abstracts

Introduction: There are the inconsistent data about a role cellular and humoral immunity in pathogenesis of type 1 diabetes mellitus.

The aim: The aim of this research was to study features of the immune status and of the activity of metabolic enzymes in lymphocytes of blood in children with type 1 diabetes.

Methods: Cellular and humoral immunity parameters were studied in 94 patients with type 1 diabetes mellitus aged 6–18 years (the mean age was 11.6 ± 0.3 yrs) and 104 controls the same age. The patients were divided into 3 groups with different duration of diabetes: up to 1 year, 1–5 years, and more than 5 years. The metabolic control of diabetes we estimated on levels of HbA1c. Population and subpopulation composition of peripheral blood lymphocytes wav studied by method indirect immunofluorescence. Serum concentrations of the main immunoglobulin classes were measured by radial immune diffusion. The activity of NAD - dependent dehydrogenases investigated by the bioluminescence method.

Results: 88% of the diabetes patients had HbA1c levels higher than 7.5%. The average HbA1c was 8.9%. At the initial stage of diabetes the immunoreactivity status in children and adolescents manifested by depression of T-cellular component of the immune system and activation of humoral immunity, this depression progressing with the disease duration. The concentration CD16+ cells was increased in all patients, irrespective of diabetes duration. The content of HLA-DR+ lymphocytes was increased at the stage of initial diabetes and decreased to the norm later. No definite patterns in changes of serum immunoglobulins A and M concentrations could be distinguished during the observed period of disease.

Conclusion: This study has shown, that there are the suppression of T-cellular immunity and the activation of humoral immunity in the initial stage of type 1 diabetes.