Expression of CD80 and CD86 on T lymphocytes and monocytes of asthmatic children

Abstract

Background: For T lymphocytes to get optimally activated, they need costimulatory signals that can be provided efficiently by costimulatory molecules CD80 and CD86
Objective: This study was done to assess the expression of costimulatory molecules CD80 and CD86 on T lymphocytes and monocytes of asthmatic children. The effect of clinical grading of asthma and intake of inhaled steroids on the level of their expression was assessed.
Methods: The study included 44 asthmatics (12 with acute asthma and 32 in between attacks) and 12 controls. The asthmatic children were classified according to clinical severity into mild (15 cases), moderate (9 cases) and severe (8 cases). Flow cytometry was performed to analyze the expression of CD80 and CD86 on blood T lymphocytes and monocytes
Results: The percentage of expression of costimulatory molecules CD80 and CD86 on T lymphocytes and monocytes were statistically higher in asthmatic children whether in acute or in between attacks compared to the control group (p<0.05). This up regulation suggests their critical role in pathogenesis of bronchial allergic inflammation in asthma. The percentage of expression of CD80 and CD86 on monocytes were significantly higher in asthmatics during their acute exacerbations compared to those in between attacks (p<0.05). Comparing the clinical subgroups of asthma, there was no statistically significant difference between mild and moderate asthmatics as regards level of co-expression (p > 0.05); however the difference was statistically significant between mild and severe cases (p <0.05).  Asthmatics on inhaled steroids showed significant lower percentage of CD80 and CD86 expression on T lymphocytes and monocytes.
Conclusion: The enhanced expression of both CD80 and CD86 on antigen
presenting cells and T lymphocytes in bronchial asthma is probably  involved in the establishment and maintenance of chronic inflammation of the airways.

Key words: Asthma, T lymphocytes, Costimulation, CD80 and CD86.