C4BPB and susceptibility to pneumonia measurement: The serum concentrations of SAA, PROZ, and C4BPB in patients with TB were significantly higher than those in healthy controls (P < 0.0001, P < 0.0001, P < 0.0001, Fig 3) but were significantly lower than those in patients with pneumonia (P < 0.0001 for each, Fig 3) or COPD (P < 0.0001, P < 0.0001, P = 0.0016, respectively, Fig 3).