Characterization of the Cytolytic T-Lymphocyte Response to a Candidate Vaccine Strain of Equine Herpesvirus 1 in CBA Mice

Abstract

The cytolytic T-lymphocyte (CTL) response to respiratory infection with equine herpesvirus 1 (EHV-1) in CBA (H-2k ) mice was investigated. Intranasal (i.n.) inoculation of mice with the attenuated EHV-1 strain KyA resulted in the generation of a primary virus-specific CTL response in the draining mediastinal lymph nodes 5 days following infection. EHV-1-specific CTL could be restimulated from the spleen up to 26 weeks after the resolution of infection, indicating that a long-lived memory CTL population was generated. Depletion of CD8+ T cells by treatment with antibody and complement prior to assay eliminated CTL activity from both primary and memory populations, indicating that cytolytic activity in this model was mediated by class I major histocompatibility complex-restricted, CD8+ T cells. A single i.n. inoculation with KyA induced protective immunity against infection with the pathogenic EHV-1 strain, RacL11. The adoptive transfer of splenocytes from KyA-immune donors into sublethally irradiated recipients resulted in a greater than 250-fold reduction in RacL11 in the lung. The elimination of both CD4+ and CD8+ T cells from the transferred cells abrogated clearance of RacL11, while the selective depletion of either subpopulation alone had little effect. These results suggested that both lymphocyte subpopulations contribute to viral clearance, with either subpopulation alone being sufficient.

Immunization with a bovine herpesvirus 1 glycoprotein B DNA vaccine induces cytotoxic T-lymphocyte responses in mice and cattle

“…Indeed, approximately 10 % of the entire CTL response is directed against gB. In equine herpesvirus-1, gB also induces CTL responses (Smith et al, 1998). We compared the CTL responses induced by BHV-1 gB when expressed by vaccinia virus, a viral vector, or by two different plasmid vectors.…”

A Review: Interactions of Equine Herpesvirus-1 with Immune System and Equine Lymphocyte

“…However the precise function of LAT is not well understood and no infectious virus is produced [25]. The locations of EHV-1 latency were identified as the trigeminal ganglion [26] [27], in lymphoid tissue draining the respiratory tract [26] [28] [29] and in peripheral blood leukocytes [28]- [30]. Smith et al [30] reported that CD5 + /CD8 + T lymphocytes were the predominant site of EHV-1 latency in peripheral blood leukocytes.…”

“…The locations of EHV-1 latency were identified as the trigeminal ganglion [26] [27], in lymphoid tissue draining the respiratory tract [26] [28] [29] and in peripheral blood leukocytes [28]- [30]. Smith et al [30] reported that CD5 + /CD8 + T lymphocytes were the predominant site of EHV-1 latency in peripheral blood leukocytes. In 2000, one study demonstrated that alveolar macrophages were also a site of latency by detecting the latent transforming growth factor β in alveolar macrophages [31].…”

An Argentine Equine Herpesvirus Strain with Special Restriction Patterns Protect Mice Challenged with a Pathogenic Strain

“…Nevertheless we could observe, coincidently with Walker et al (1998) that challenge infection in SPv immunized mice resulted in a mark increase of mononuclear cells around blood vessels and bronchioles. Besides, the reason of attenuation and genomic properties was determined in the KyA strain (Matsumura et al, 1993;Smith et al, 1998). In addition, the results found by studies conducted recently by Ibrahim el et al (2004) show that the intergenic region between ORF62 and ORF63 of the BamHI ÔeÕ fragment could also play various roles in the virus growth and the virulence.…”