Natural killer cell activity of chicken intraepithelial leukocytes against rotavirus-infected target cells

Abstract

Intraepithelial leukocytes (IEL) and splenocytes collected from uninfected and rotavirus-infected chickens were evaluated for cytotoxic activity against a natural killer (NK) cell-susceptible lymphoblastoid cell line (LSCC-RP9) and against rotavirus-infected chick kidney cells in 4-h chromium-release assays. Both splenocytes and IELs from uninfected and rotavirus-infected chickens were cytotoxic for LSCC-RP9, and the levels of this NK cell activity were not altered by infection of the host with rotavirus. IELs but not splenocytes from uninfected and rotavirus-infected chickens were cytotoxic for rotavirus-infected but not for uninfected chick kidney cell targets. Because this cytotoxic activity was not induced nor altered by rotavirus infection of the host, and was not major histocompatibility complex-restricted, it was considered to be due to NK cell activity. The cytotoxicity of IELs against rotavirus-infected target cells was dose-dependent; however, there was some suppression of cytotoxic activity at high effector to target cell ratios. There were no differences in the cytotoxic activities of IELs collected from the duodenum versus the jejunum. The in vitro cytotoxic activity of IELs against rotavirus-infected target cells suggested that NK cell activity may be an important immune response to rotavirus infections in vivo. The absence of cytotoxic activity by splenocytes against rotavirus-infected target cells indicated that there may be different subpopulations of NK cells in the spleen and intestinal epithelium of chickens.

Avian rotavirus enteritis – an updated review

“…Paradoxically, chickens and turkeys were more susceptible to experimental disease with RV in older ages (56 to 119 days) than birds in first few weeks of life (Yason & Schat 1986b, 1987. However, in field situation, evidence indicates that most of turkeys and chickens will have been infected, and presumably will have developed some immunity, well before this age (Myers & Schat 1990a, 1990b). Added to this, Jones et al (1979) reported lack of age resistance to disease as well as an outbreak of rotaviral diarrhea that occurred between 32 and 92 weeks of age in commercial laying hens.…”

“…Rotavirus specific IgM, IgG and IgA were detected in serum where intestinal antibody response entirely consisted of IgA (Figure 3). Myers and Schat (1990a), as an important in vivo immune response, demonstrated NK cell activity in chick intra-epithelial leukocytes against RVs. Myers and Schat (1990b) further reported that intestinal antibodies (IgA) alone are not only a mediator for recovering from disease, but also must regarded as development of resistance to re-disease.…”

“…Also, it has been reported that mutation in NSP4 may act as a factor for variation in virulence of AvRV isolates (Zhang et al 1998). In host, for countering viral pathogenesis, intra-epithelial lymphocytes (IEL) may have a key role to play together with a prompt natural killer (NK) cell activity (Myers & Schat 1990a).…”

Studies on the cell-mediated immune response of the gut-associated lymphoid tissue (GALT) in poultry

“…The results fi'om Chai and Lillehoj's study (1988) revealed the NK cell activity of chicken i-IEL against tumor cells was greater in the jejunum than in the duodenum. However, Myers and Schat (1990b) did not observe any difference in NK cell activity of chicken i-IEL collected from the duodenum or the jejunum.…”

“…The NK cell cytotoxicity of chicken i-EEL against chicken tumor cells has been demonstrated by . Myers and Schat (1990b) have demonstrated the NK cell activity of chicken ilEL against rotavirus-infected target cells. In this study, it was suggested that NK cell activity of i-IEL may be an important immune response to rotavirus infection in vivo.…”