ABSTRACT: BACKGROUND & AIMS:In our previous study, a Seesaw model was proposed for the fluctuation of crucial anti- (IL-10) and pro-inflammatory (Il-6 & IL-17A) cytokines through vitamin D3. In this paper, however, it is intended to extend the mentioned model by assessing the expression mRNA levels of IL-27 and TGF-?1 as well as the changes of plasma levels of IL-27, TGF-?1, IL-17A, IL-10, and IL-6 after treatment by vitamin D3. METHOD:Venous blood samples were drawn from Healthy Participants (HP, n = 25) and First-Degree Relative Participants (FDRP, n = 25) as control groups and Multiple Sclerosis Participants (MSP, n = 25) before and after eight weeks of supplementation with 50000 IU vitamin D3. The mRNA expression and plasma concentrations were gauged by using Real-Time PCR and ELISA assay, respectively. RESULTS:The mRNA surfaces of IL-27, as well as TGF-?1, were up-regulated. However, the plasma levels of TGF-?1, IL-17A, and IL-6 were significantly different among the three groups. In addition, the plasma levels of IL-27, TGF-?1, IL-10, IL-17A, and IL-6 significantly changed following the administration of vitamin D3. CONCLUSION:The findings of this paper illustrate that anti-inflammatory cytokines could have a key role in immunomodulatory functions due to their anti-inflammatory functions. To conclude, this might contribute to preventing the pathophysiological process of MS. Also, the proposed model could be used as a preventive way on disposed people to multiple sclerosis, particularly in first degree relatives of these patients.