Differential cell-mediated immune response to S. mutans in children with low and high dental caries

Role of cell-mediated immune response (CMI) in dental caries was studied in 171 subjects, comprising of 86 children with low caries (LC), 31 with high caries (HC), and 54 age matched controls. [3H]thymidine mediated lymphoblast transformation test (LTT) using mutans streptococci antigen as stimulant was used to study the stimulation index (SI) of in vitro cultured lymphocytes from these children. The analysis revealed low stimulation index in high caries children whereas low caries children exhibited high stimulation index normally ranging between 2 to 6. The findings indicated that low caries children had strong CMI response as compared to high caries children. Although, the findings are based on limited number of samples, it certainly lays emphasis on protective or regulatory role of CMI in different phases of dental caries.