Antigen specific immune enhancement of innate and acquired immunity by pearl in ashed form

The present study evaluated mineral compound, pearl in ashed form [PAF], for its potential as oral immunomodulator. ICP-MS, atomic absorption spectroscopy, CHNS analysis and XRD analysis were used for characterization of PAF. Surface antigen markers (TLR-2/4 and CD-80/86) were studied by flow cytometry. At dose concentration of 25, 50, 100 and 500 μg/kg body wt., administrated orally for 10 days, TLR-2 expression on murine peritoneal macrophage increased while TLR-4 expression was reduced as compared to control. There was an increase in OVA and mitogen (Con-A) specific lymphocyte proliferation in OVA immunized mice. Also, level of both Th1 (IL-2/IFN-γ) and Th2 (IL-4/IL-10) cytokines, and level and titer of total IgG, IgG1, IgG2a and IgG2b of OVA immunized mice significantly increased. The level of Inflammatory cytokines (IL-1β and TNF-α) did not increase significantly. Enhancement in T and B cell immune responses may be possibly due to significantly enhanced expression of CD-80 and CD-86 co-stimulatory signals as observed using flow cytometry. Also, enhanced phagocytic activity and DTH response exhibit stimulatory effect of PAF on innate and cell mediated immune response. Histopathological analysis of liver, kidney and spleen and analysis of other toxicity parameters, such as effect on body weight, lymphoid organ weight and cellularity, revealed PAF to exhibit no toxic effects. PAF seems to be a promising balanced Th1 and Th2 directing immunomodulator, possibly activating TLR2 through TIR domain-containing adaptor inducing interferon β (TRIF)-dependent pathway that leads to T-cell activation and promotes effective immune responses and may find useful application clinically.