Fig 3.

The correlation between the concentration of tumour necrosis factor (TNF)-α and the growth of Mycobacterium tuberculosis H37Rv in whole blood cultures. The secretion of TNF-α in whole blood cultures was studied by quantification of the cytokine in the culture supernatants after 0, 48 and 96 h of infection with reporter M. tuberculosis H37Rv. The analysis of the results for correlation, using spss version 13·0, between M. tuberculosis H37Rv growth and concentration of TNF-α showed that M. tuberculosis H37Rv growth measured as growth ratio (GR) at 96 h of culture correlated directly with the concentrations of TNF-α at 48 h (r = 0·722, P ≤ 0·0001) and at 96 h of culture (r = 0·747, P ≤ 0·0001)