[Study on antimicrobial activity of human hemoglobin and its fragments both in vitro and in vivo]

Abstract

Objective: To isolate human hemoglobin and its fragrments, compare their antimicrobial activity in vitro and pilot study of their antimicrobial activity in vivo.

Methods: The alpha and beta chains of hemoglobin were separated by cation exchange chromatography and gel chromatography; The alpha and beta chains were cleaved by cyanogens bromide respectively. The cleaved fragments were purified by reverse phase high performance liquid chromatography. Antimicrobial activity of hemoglobin and its fragments was determined by agrose radial diffusion assay. After establishment of E. coli vaginal infection model, the rats were randomized into the experimental group (hemoglobin group) and the control group. The histologically pathological section was observed.

Results: Hemoglobin, alpha/beta chain and their fragments had similar antibacterial activities in vitro, which were mainly against Gram-negative bacteria E. coli; except alpha1-32 had a comparatively lower activity. Antimicrobial activity in vivo: a comparison of the hemoglobin group with the matrix control group (no treatment after infection), the surface layer of vaginal stratified squamous epithelium was smoother, inflammatory cells were significantly reduced in the lamina propria and congestion was obviously decreased.

Conclusion: Human hemoglobin and its fragments had antibacterial activity in vitro, hemoglobin might relieve the inflammation of E. coil vaginal infection in rats moreover.