Table II.

MDC enhances phagocytic and killing activities of macrophages in vitroa

MDC (ng/ml)Incubation (h)E. coli CFUb (× 103)Phagocytosisc IndexKilling Rated (%)
0141.8 ± 3.91.0
337.2 ± 3.511.0
20162.6 ± 7.91.5
339.0 ± 7.537.7
100197.1 ± 26.3*2.3
348.5 ± 8.451.1
  • a Peritoneal macrophages, recovered from normal mice, were preincubated with MDC for 1 h and challenged with E. coli (1 × 106) recovered from CLP mice. The data are representative of the two individual experiments (n = 6 each). ∗, p < 0.05, when compared with control (MDC = 0 ng/ml).

  • b After 1-h incubation, the wells were extensively washed and the cells were lysed with 0.5% Triton X-100 for phagocytosis assay. Wells were replaced with fresh medium and cultured for an additional 2 h, after which the cells were lysed with 0.5% Triton X-100 for killing assay. The cell lysates were serially diluted and placed on TSA blood agar plates, and CFU within the cells were determined.

  • c Phagocytosis index was standardized by the data obtained from control (MDC = 0 ng/ml).

  • d Killing rate = [1 − (CFU at 3 h/CFU at 1 h)] × 100.