Relationship Between HBsAb Response, Expression of TLR 2, 3 and 4, and Birth Season in 3 - 5-Year-Old Children

background: vaccination is known as one of the effective methods for the prevention of infectious diseases. birth season as an environmental factor can play an important role in the immune response to vaccines. objectives: this study aimed to determine the association between hepatitis b virus (hbv) surface antibody (hbsab), the expression of tlr2, 3 and 4 genes in response to the hepatitis b vaccine, and the birth season of children aged 3 - 5 years. methods: in this study, 72 children aged 3 - 5 years born in winter and summer (36 in each group) were enrolled for blood sample collection. then, the hbsab titer and tlr2, 3, and 4 were determined by the elisa method and real-time pcr, respectively. results: the results indicated that the expression of tlr2, 3, and 4 genes was higher in the winter-born group than in the summer-born group. however, this difference was not statistically significant (tlr2 p value = 0.5; tlr3 p value = 0.06; tlr4 p value = 0.16). the overall efficacy of hbsab was 72.2%. the average level of antibody was greater in the summer-born group than in the winter-born group but this difference was not statistically significant (p value = 0.3). conclusions: although tlr2, 3, and 4 expression levels were higher in the winter-born group than in the summer-born group and the antibody titer was higher in summer than in winter, these differences were not statistically significant. however, more research is needed to prove these relationships.