Hong Kong Med J 2013;19(Suppl 5):S27-30
Effect of human cathelicidin and fragments on HIV-1 enzymes
JH Wong, A Legowska, K Rolka, TB Ng, M Hui, CH Cho, WW Lam, SW Au, OW Gu, DC Wan
School of Biomedical Sciences, The Chinese University of Hong Kong
1. Cathelicidins are small cationic antimicrobial peptides. Cathelicidin LL-37 and its fragments inhibit HIV replication. Whether there is any inhibitory effect on enzymes essential to the HIV life cycle is not known. Therefore, human cathelicidin LL-37 and its fragments were investigated for their ability to inhibit HIV reverse transcriptase, protease, and integrase.
2. Human cathelicidin LL-37 and its fragments LL13-37 and FK- 16 inhibited HIV-1 reverse transcriptase dose-dependently, with respective IC50 values of 15, 7, and 70 μM.
3. The three peptides inhibited HIV- 1 protease with weak potency, achieving 20 to 30% inhibition at 100 μM. The mechanism of inhibition was a protein-protein interaction as revealed by surface plasmon resonance.
4. The peptides did not inhibit translocation of HIV-1 integrase, labelled with green fluorescent protein, into the nucleus.
5. The peptides were not toxic to human peripheral blood mononuclear cells.