Expression of chicken NK-Lysin and its role in chicken Coccidiosis induced by Eimeria necatrix

Authors: KIM, WOO - Gyeongsang National University; MIN, WONG - Gyeongsang National University; PARK, KWANG - Gyeongsang National University; Lillehoj, Hyun; FERNANDEZ-COLORADO, CHERRY - University Of The Philippines; FLORES, ROCHELLE - Gyeongsang National University; CAMMAYO, PAULA - Gyeongsang National University; NGUYEN, BINH - Gyeongsang National University

Submitted to: Korean Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/11/2021
Publication Date: 10/31/2022
Citation: Kim, W., Min, W., Park, K.I., Lillehoj, H.S., Fernandez-Colorado, C.P., Flores, R.A., Cammayo, P.L., Nguyen, B.T. 2022. Expression of chicken NK-Lysin and its role in chicken Coccidiosis induced by Eimeria necatrix. Korean Journal of Parasitology. 59:439. https://doi.org/10.3347/kjp.2021.59.5.439.
DOI: https://doi.org/10.3347/kjp.2021.59.5.439

Interpretive Summary: Avian coccidiosis is an intestinal disease caused by several distinct species of intestinal parasite, Eimeria. Infection with Eimeria parasites costs more than $13 billion globally, and novel treatment method is needed to control coccidiosis in poultry due to the anti-coccidial drug regulation. In this report, ARS scientists and scientists from several universities collaborated to study the effect of host-derived antimicrobial peptide called NKlysin against E. necatrix parasites. NKlysin was previously shown to directly kill some Eimeria species but nobody has shown if NKlysin kills E. necatrix species. The results of this report show that chicken NKlysin is involved in mediating protection against coccidiosis in E. necatrix infection since E. necatrix-infected chickens show very high level of NKlysin gene expression in the gut where parasites are undergoing intracellular development. Understanding the role of host antimicrobial protein in host defense against E. necatrix infection will lead to the development of novel prevention strategy against coccidiosis. These findings will help pharmaceutical companies to develop new drugs to reduce economic losses due to coccidiosis.

Technical Abstract: Coccidiosis in chickens is an intestinal parasitic disease caused by protozoan parasites named Eimeria spp. In some Eimeria infections, intestinal lymphocytes are known to highly express chicken NK-lysin (cNK-lysin), an antimicrobial peptide with anticoccidial activity. Therefore, this study aims to investigate the expression of cNK-lysin in E. necatrix-infected chickens and study its role in E. necatrix infection. The expression of cNK-lysin transcript was significantly increased in E. necatrix sporozoites-treated lymphocytes. In E. necatrix infection, cNK-lysin transcript was induced in intestinal lymphocytes, but not in the spleen. The recombinant cNK-lysin exhibited anticoccidial activity against E. necatrix sporozoites as well as immunomodulatory activity on macrophages by inducing proinflammatory cytokines. These results indicated that E. necatrix infection induces high local expression of cNK-lysin and the secreted cNK-lysin is involved in protection against coccidiosis.