Rapamycin and Filgrastim effect on Regulation of Peripheral and Splenic Tissue B- and T-lymphocytes in TAA-Induced Splenic Injury in Rats

Background: Splenomegaly; a bigger spleen pool for blood, affecting circulating and its resident blood cells. Aim: this study aimed to evaluate the effects of Rapamycin (RAPA) and Filgrastim (FIL) treatment separately and in combination on the blood and splenic lymphocytes in thioacetamide (TAA)-induced splenic injury. Methods: Thirty-six adult male albino rats were divided into six groups; negative control, TAA-treated, TAA+RAPA-group,TAA+FIL-group, TAA+RAPA+FILgroup < /p> and TAA+RAPA then FIL-group. For each group, complete blood count (CBC), flow cytometry for blood CD3 and CD19 lymphocytes, and immunohistochemical detection of splenic CD3 and CD20 positive lymphocytes were performed. Results: the results demonstrated significant increased blood CD3 and CD19 lymphocytes with increased splenic CD3 and CD20 lymphocytes, decreased Red blood cells (RBCs), Hemoglobin (Hb) and increased White blood cells (WBCs) with marked effect on spleen morphology after TAA injection. RAPA treatment showed decreased splenic lymphocytes while increased blood T-cells with increased Hb levels and granulocytes percentage, lowered WBCs count with more decreased lymphocytes percentage and further reduced Platelets (Plts) count. Also, FIL monotherapy showed decreased splenic lymphocytes with decrease in circulating WBCs with increased Hb levels. Both combination treatments caused an increment in blood CD3 lymphocytes, while only decreased CD19 lymphocytes with TAA+RAPA+FIL-group. Conclusion: Splenic and blood lymphocytes were affected by RAPA and FIL separately or in combination as combination showed a synergistic effect on spleen lymphocytes.