We investigated the relationship between pulmonary infection and antimicrobial peptides, endotoxins and lipopolysaccharide-binding protein (LBP). Lymphocyte leanages indicating the immune response determined by clusters of differentiation (CD) and changes of T-, B-lymphocytes ratio.  We tested 42 individuals with pneumonia on chronic hepatitis C background. Endotoxin and lipopolysaccharide-binding protein (LBP) were determined using the ELISA technique. Determination of the CD clusters carried out by indirect immunofluorescence reaction, while the circulating immune complexes (CIC) identified by sedimentation method with a 3.5% solution of polyethylene glycol. Statistical processing of the results carried out using the Wilkinson U-test (Mann - Whitney). We have found that in the group of patients with hepatitis aggravated by pneumonia, CD25+ lowered approximately three times. When pneumonia, indicator CD25+ correlated with severity of disease. Endotoxin elevated even up to 57.7 IU/ml, the same direction changed defensin concentration. LPB raised nearly 19 times, while defensins – about 38 times. In this study, we present our version of the involvement of immune components in self-protection in hepatitis C-associated pneumonia. Keywords: ALT, bilirubin, circulating immune complexes, defensin, Endotoxin, lipopolysaccharide binding protein