M. V. Makarenko¹, D. O. Semeniuk², I. O. Starenka², A. P. Pogribna³,
I. V. Sokol⁴, L. I. Martinova¹, D. O. Govsieiev⁴

¹Institute of Postgraduate Education,
Bogomolets National Medical University, Kyiv Ukraine;
²ESC Institute of Biology and Medicine,
Taras Shevchenko National University of Kyiv, Ukraine;
e-mail: dmyt.semenyuk@gmail.com;
³Institute of Molecular Biology and Genetics, NAS of Ukraine, Kyiv;
⁴Kyiv City Maternity Hospital No 5

Received: 24 September  2018; Accepted: 13 December 2018

HBD-2 – a member of β-defensin family of antimicrobial peptides – is known to permeabilize cell membranes of susceptible cells, but the mechanism of such interactions is poorly understood. In our study, we have used a hemolytic model to explore the kinetic properties of HBD-2 interactions with membranes of human erythrocytes. We ran hemolytic assays with a wide range of both HBD-2 and erythrocyte concentrations, as well as varying pH values, incubation times, and osmotic strengths; each in the presence or the absence of inhibitory substances such as proteins and salts. The results show that HBD-2 cell membrane permeabilization is both dose- and time-dependent (with plateau effect observed in each case), and inversely dependent on erythrocyte concentration. HBD-2 interactions with cell membranes highly depend on pH value and the presen­ce of inhibitors but are not affected by tested osmotic strength range. Our findings suggest that interactions of HBD-2 with cell membranes are mainly electrostatic in nature and are limited by released cell content. We have developed a speculative model of such interaction based on our results.