ABSTRACT
Objective: To investigate the effects of superagonistic CD28-specific monoclonal antibody JJ316 (supCD28 MAb) on in vivo proliferation of rat CD4 + CD25+ Fox P3+ Treg(T reg) cells and on allograft rejection reaction in a rat orthotopic tracheal transplantation model. Methods: Rat orthotopic tracheal transplantation models were divided into two groups in the present study. The experimental group was treated with supCD28 MAb(0.5 mg/rat) via intraperitoneal injection on the day of transplantation. Control group was injected with mIgG (0.5 mg/rat). The proportions of CD4+ CD25+ FoxP3+ T cell population in cervical lymph nodes, spleen and peripheral blood monocytes were examined by flow cytometry 5 days after operation. The tracheas were also harvested for histological evaluation. Results: The allografts of the experimental group showed greatly improved airway obliteration, infiltration of inflammatory cells, and respiratory epithelial injury compared with those of the control group. Furthermore, The experimental group had significantly increased CD4+CD25+ FoxP3+ Treg cell population in the lymph nodes, spleen and peripheral blood monocytes compared with those in the supCD28 MAb group ([5.8±1.2]% vs [16.9±4.2]%, [14.8±3.6]%, and [2.9±0.9]%, [3.3±1.3]% vs [2.8±1.4]%, respectively, P<0.05). Conclusion: SupCD28 MAb can attenuate airway inflammation injury after orthotopic tracheal transplantation.