Demonstration of bovine CD8+ T-cell responses to foot-and-mouth disease virus.

Abstract

The aim of this study was to investigate the importance of cellular immunity in foot-and-mouth disease in cattle, in particular to determine whether a CD8 M T-cell response could be detected, as these cells may play a role in both immunity and virus persistence. As attempts to characterize classical cytotoxic T cells had yielded non-reproducible results, largely due to high backgrounds in control cultures, a proliferation assay was developed that was demonstrated to detect antigenspecific, MHC class I-restricted bovine CD8 M cells responding to foot-and-mouth disease virus (FMDV). Proliferative CD8 M T-cell responses were detected consistently from 10 to 14 days following infection with FMDV and typically lasted 3-4 weeks. The role of CD8 M T cells in control of the disease, in particular their relevance for the establishment of persistence, may now be investigated.

Identification of T-Cell Epitopes in Nonstructural Proteins of Foot-and-Mouth Disease Virus

“…Anti-class I MAb gave lower inhibitions, in agreement with the previous reports on porcine lymphoproliferation against whole virus (14,45) and FMDV capsid protein peptides (7). These inhibitions might relate to the high proportion of CD8 ϩ CD4 ϩ double-positive cells found in swine (58), dominated by memory Th lymphocytes (50,59).…”

“…Despite animal to animal variation, 19 peptides were stimulated in vitro lymphocytes from, at least, four of the six infected pigs analyzed ( Table 2). The responsive peptides define T-cell regions efficiently recognized by swine lymphocytes at the following amino acid positions: 3A and -[121-135], 3B [13][14][15][16][17][18][19][20][21][22][23] and - [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53], and 3C [191][192][193][194][195][196][197][198][199][200][201][202][203][204][205][206][207][208][209][210]. Eleven of these peptides were also recognized by lymphocytes from at least three of the five heterotypically reinfected pigs analyzed (Table 3).…”

“…These inhibitions might relate to the high proportion of CD8 ϩ CD4 ϩ double-positive cells found in swine (58), dominated by memory Th lymphocytes (50,59). Certainly, it must also be considered that the animals were infected with FMDV and, therefore, that stimulation of CD8 ϩ cells through class I presentation could have occurred (14). The implication of CD8 ϩ lymphocytes in protective responses to FMDV remains largely unknown and thus its characterization was not pursued here.…”

Foot-and-mouth disease virus: a long known virus, but a current threat

“…Thus, it appears that the T cell responses mediated by CD4 + cells are required for protective immunity against FMDV, by participating in the production of antiviral antibodies [31,58,240] and by maintaining the appropriate microenvironment needed for a synergistic immune response. The induction of FMDV-specific effector cytotoxic T lymphocytes (CTL) has been difficult to evaluate [5,50,190,215]. Recent studies have shown that FMDV infection results in a rapid reduction of MHC class I expression on susceptible cells [216].…”

Şap hastalıklı koyunlarda serum nitrik oksit düzeyi ve adenozin deaminaz aktivitesinin araştırılması

“…Şap hastalığına karşı korunmada, antikorların rol aldığı ileri sürülmüşse de (32), son yıllarda yapılan immunolojik çalışmalar sonucunda hücre aracılı bağışık-lık cevaplarının, özellikle de T-hücre cevabının önemli olduğu ortaya konmuştur (6,15,20). Virus ile enfeksiyonu ya da aşılamayı takiben, CD4+ ve CD8+ hücreleri içeren spesifik T-hücre aracılı antiviral cevapların şekil-lendiği ve virusun organizmadan uzaklaştırılmasında hücre-aracılı bağışıklığın rol aldığı rapor edilmiştir (5,24).…”