Predominant T-cell receptor Vbeta usage of intraepithelial lymphocytes during the immune response to enteric reovirus infection

Abstract

Previous studies have found that intraepithelial lymphocytes (IEL) contain virus-specific cytotoxic T lymphocytes (CTL) that increase dramatically during the course of virus infection. In the present study, the T-cell receptor (TCR) V␤ pattern used by IEL against reovirus enteric infection was investigated both in conventional and in germfree mice. IEL were isolated by a modified rapid method, and their expression of 13 TCR V␤s was examined by flow cytometric analysis. The virus-specific CTL activity of each TCR V␤ subset was assessed by subtraction with coated Dyna beads by a nonradioactive assay. There was a preferential perturbation of TCR V␤s following virus challenge, including increases in cells expressing V␤7,-12,-14, and-17 in conventional mice and V␤2,-12, and-17 in germfree mice. In conventionally reared mice, IEL maintained and restimulated in culture had a preferential use of TCR V␤9,-12, and-17. TCR V␤12 and-17 subfamilies were found amplified in all conditions. Furthermore, TCR V␤12 and-17 accounted for 37 and 77% of the virus-specific CTL activity, respectively, after in vitro restimulation. This study provides evidence that virus-specific CTL activity may be due to the oligoclonal expansion of TCR V␤ subfamilies in IEL. Our findings suggest that in vivo infection selectively presents few T-cell epitopes and that the correct identification of these T-cell epitopes would increase the likelihood of success when designing subunit vaccines.

How the gut senses its content

“…, 2001), to show that CTL responses are more intense in the intestine than in the spleen after oral immunization, although the kinetics of induction were similar in the two compartments (Huleatt et al , 2001; Pope et al , 2001). The CD8 intestinal response is also associated with higher effector capacities, with an oligoclonal TCR repertoire, and with persistent effector/ memory phenotypes (Huleatt et al , 2001; Marshall et al , 2001; Masopust et al , 2001; Chen et al , 1997). Moreover, intestinal CTL activation is dependent on a distinct pattern of co‐stimulatory molecules (Kim et al , 1998).…”

Lineage-specific differences among CD8+ T cells in their dependence of NF-κB/Rel signaling

“…To determine the effect of I O B § ( ¿ N) on virusspecific CTL responses after mucosal infection, mice were infected with reovirus perorally. Reovirus type 1 binds avidly to M cells overlying Peyer's patches, thus permitting entry into the host and activation of humoral and cellular virus-specific immune responses which include TCR § g -bearing CTL that lyse virus-infected cells in an MHC-restricted manner following secondary restimulation in vitro [22][23][24][25][26]43]. Following enteric infection with reovirus, the recovery of IEL and of cells from Peyer's patches of NTg controls were five-and sevenfold greater than from I O B § ( ¿ N) mice (Fig.…”

“…5A). To determine the CTL activity of reovirus-reactive cells, virus-specific precursor CTL were isolated from Peyer's patches and the IEL compartment, maintained 4 days in vitro in the presence of reovirus-infected APC, and then assayed using virus-infected targets [25,43,44]. Due to the very low numbers of cells (typically 1 × 10 5 -2 × 10 5 ) recoverable from I O B § ( ¿ N)-Tg mice, these assays provided only enough cells for CTL assays performed at a single E/T ratio but did permit comparison of the CTL activity of equal numbers of input T cells.…”

“…Small intestines from Tg and NTg mice were harvested for isolation of IEL and Peyer's patch lymphocytes as described previouly [43]. Briefly, Peyer's patches were dissected free of surrounding tissue, washed in RPMI 10, crushed, and passed through a nylon mesh.…”

Regulation of polymeric immunoglobulin receptor by reovirus in intestinal epithelial cells

“…Virusspecific cytotoxic T-lymphocytes (CTLs) are induced within the PP following intestinal infection (226). CTLs migrate via efferent lymphatic vessels to the mesenteric lymph nodes, then through the thoracic duct lymph and the systemic circulation to the spleen (226) or to intestinal mucosal sites such as the intestinal epithelium where virus-specific cells can be found among the intraepithelial lymphocytes (IELs) (64,77,224). Parenteral infection with reovirus induces virus-specific CTLs in the draining peripheral lymph nodes and spleen (215,390).…”