Since phagocytosis of bacilli by normal and by PKC-α deficient cells was different, we presented the www.selleckchem.com/products/byl719.html survival of BCG as fold increase in the number of intracellular bacilli as compared to the initial phagocytosis (Fig. 2C). The specifiCity of PKC-α SiRNA was confirmed by transfecting mouse macrophage cell line, J774A.1 and showing that SiRNA blocked PKC-α, only in THP-1 cells (data not shown). Figure 2 Phagocytosis and survival of BCG in PKC-α deficient THP-1 cells. THP-1 cells were incubated
in the presence of 30 nM PMA for 24 h. Then cells were transfected with 20 nM SiRNA and level of PKC-α were determined by immunoblotting. (A) 24 h after transfection, level of PKC-α and PKC-δ in cells transfected with SiRNA targeting PKC-α or scrambled SiRNA, (B) 24 h after transfection, (ΔA) cells transfected with SiRNA targeting PKC-α and (S) cells transfected with scrambled SiRNA and control cells (C) were infected with BCG (MOI = 1:10) for 2 h, washed and remaining extracellular bacilli were killed by amikacin treatment this website for 1 h and lysed in 0.05% SDS and plated. Colony forming units (cfu) were determined after 4 week of incubation. Tukey (T) test was performed for statistical analysis of data (C) Survival of BCG in THP-1 cells transfected with either SiRNA targeting PKC-α (ΔA) or scrambled
SiRNA (S) after 24 and 48 h, since phagocytosis of BCG in control and PKC-α deficient cells was different, CFU at 0 Decitabine h was considered 1 and survival of BCG is presented as fold increase in the number of cfu as compared to the initial phagocytosis. Data are means ± standard deviations from three independent experiments each performed in 4 replicates. (** = p < 0.005). To clearly understand the specific role of PKC-α in the phagocytosis and survival of mycobacteria,
we used MS (which does not downregulate PKC-α) for infection. Knockdown of PKC-α resulted in the significant (p < 0.0001) decrease in the phagocytosis of MS by macrophages (Fig. 3A). Results show that phagocytosis of MS is 2.6 fold less in PKC-α deficient cells as compared to normal cells. Inhibition of phagocytosis was specific to the inhibition of PKC-α as knockdown of PKC-δ did not inhibit the phagocytosis or survival (Fig. 3A, 3B and 3C). When survival of MS in macrophages deficient in PKC-α was compared with normal cells, we found that survival of MS was increased in the PKC-α deficient macrophages. Since phagocytosis of MS by normal and PKC-α deficient cells was different, we expressed intracellular survival of MS as percentage of the initial bacilli uptake. In normal macrophages, only 25% of initial bacilli survived as contrast to 65% survival in PKC-α deficient cells (Fig. 3B). The results were confirmed with J774A.1 cells using Go6976 (inhibitor of PKC-α) which represented similar level of inhibition in phagocytosis (Fig. 3D). Figure 3 Phagocytosis and survival of MS in PKC-α deficient THP-1 cells.