Submitted to: Journal of Parasitology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/19/2007
Publication Date: 7/8/2008
Citation: Hong, Y.H., Lillehoj, H.S., Siragusa, G.R., Bannerman, D.D., Lillehoj, E.P. 2008. Antimicrobial activity of chicken NK-lysin against Eimeria sporozoites. Avian Diseases. 52:302-305. Interpretive Summary: Avian coccidiosis is caused by several distinct species of Eimeria which infects intestine and causes a significant economic losses to poultry industry worldwide. Currently live parasite vaccine is available but alternative control strategy for this disease is being sought by many industry scientists due to potential problems associated with using live parasites in the birds. In this paper, ARS scientists collaborated with scientists at ARS in Georgia and University of Maryland to investigate chicken NK lysin, a new anti-coccidial peptide which is secreted by chicken's own immune cells during coccidiosis. Antimicrobial peptides such as NK-lysin are widespread in nature and have been characterized in mammalian as well as avian species. This paper showed that chicken NK lysin possesses lytic activities against sporozoites of Eimeria and is produced high amount during coccidiosis. This new finding suggests that we need to better study NK lysin as a potential natural therapeutic peptide that can be applied in the field to treat coccidiosis. This information will provide important new knowledge which poultry industry can use to develop new strategy against coccidiosis in chickiens.
Technical Abstract: NK-lysin is an antimicrobial and antitumor polypeptide that is considered to play an important role during innate immunity. Chicken NK-lysin is a member of the saposin-like protein family and exhibits potent antitumor cell activity. To evaluate the antimicrobial properties of chicken NK-lysin, we examined its ability to reduce the viability of various bacterial strains and two species of Eimeria parasites. Culture supernatants from COS7 cells transfected with a chicken NK-lysin cDNA, or His-tag purified NK-lysin from the transfected cells, showed high cytotoxic activity against E. acervulina and E. maxima sporozoites. In contrast, no bactericidal activity was observed. Future studies using synthetic peptides derived from NK-lysin may be useful for pharmaceutical and agricultural uses in the food animal industry.