Modulation of Erythroid and Immune Cell Markers by Vitamin D and Tinospora cordifolia in infected Mice

TER-119 is a key marker of mature erythroid cells, which is known for its role in maintaining erythrocyte membrane stability. VLA-4 (CD49d/CD29), an adhesion molecule, facilitates the interaction between immune cells and vascular endothelial cells, especially during inflammation, favoring leukocyte migration. While Vitamin D (VD) and Tinospora cordifolia (TC) are recognized for their immunomodulatory effects, there are limited data regarding their combined effect on erythropoiesis and immune response, particularly about the expression VLA-4 on erithroid cell subset (TER-119) and imunocompeten granulocyte cell subset (Gr-1). This study aimed to evaluate the impact of VD, TC, and their combination on these markers in murine models. The mice were divided into five groups: normal (N), infection control (I), treated with VD (VD, 0.325 μg/kg BW), treated with TC (TC, 100 mg/kg BW), and combination treated (VD+TC). After 28 days of oral treatment, all groups except the normal group received inactivated intraperitoneal injections of E. coli. Flow cytometry revealed that the infection increased the expression of VLA-4 in GR granulocytes (7.03%) compared to the normal group (6.03%). Treatment of VD and TC individually approached expression to normal levels (5.14% and 4.75%, respectively), while their combination further reduced VLA-4 expression to 2.97%. Analysis of VLA-4⁺ TER-119⁺ cells showed the lowest expression in the combination group (1.43%) compared to normal (5.51%), with no statistically significant improvement in erythroid development. These findings suggest that while VD and TC individually modulate the expression of immune markers VLA-4 on erythroid and also on granulocytes, their combination provided additive benefits which was not statistically significant. Further studies are needed to explore the optimal dosage and timing to exploit potential synergistic effects.