Severe acute respiratory syndrome (SARS) is a highly contagious and life

Severe acute respiratory syndrome (SARS) is a highly contagious and life threatening disease with a fatality rate of almost 10%. CD4+ and CD8+ T cells. A dominant memory CD8+ T cell response against SARS-CoV nucleocaspid protein (NP; amino acids 216 to 225) was then defined in SARS-recovered individuals transporting HLA-B*40:01 a HLA-B molecule present in approximately one-quarter of subjects of Asian ethnicities. To reconstitute such a CD8+ T cell response we isolated the alpha and beta T cell receptors of the HLA-B*40:01-restricted SARS-specific CD8+ T cells. Using T cell receptor gene transfer we generated SARS-specific redirected T cells from your lymphocytes of normal individuals. These designed CD8+ T cells displayed avidity Ginsenoside Rh2 and functionality comparable to that of natural SARS-specific Ginsenoside Rh2 memory CD8+ T cells. They were able to degranulate and produce gamma interferon tumor necrosis factor alpha and macrophage inflammatory proteins 1α and 1β ITM2A after antigenic activation. Since there is no effective treatment against SARS these transduced T cells specific for an immunodominant SARS epitope may provide a new avenue for treatment during a SARS outbreak. INTRODUCTION No severe human disease associated with coronaviruses was reported until the outbreak of severe acute respiratory syndrome (SARS) in late 2002 in Guangdong China (22 29 It affected more than 8 0 patients and caused nearly 800 deaths in more than 30 countries. The etiological agent of the Ginsenoside Rh2 syndrome was identified Ginsenoside Rh2 as a novel coronavirus termed SARS coronavirus (SARS-CoV) (5 10 17 The SARS-CoV genome encodes the replicase genes (open reading frame 1a [ORF1a] and ORF1b) and four structural proteins (spike [S] nucleocapsid [NP] membrane [M] and envelope [E]) together with eight other accessory proteins namely 3 3 ORF6 7 7 8 8 and 9b. Recent studies have indicated the importance of T cells in viral clearance during a main contamination of SARS-CoV (3 32 SARS-specific memory T cell responses against the structural proteins S M E and NP are present in SARS recovered patients (6 11 13 but it is usually unclear whether SARS elicits a lasting memory T cell response. Most studies focus on the surface glycoprotein S protein and to date several cytotoxic-T-lymphocyte (CTL) epitopes have been recognized in the S protein (15 25 26 27 28 33 However a detailed analysis and epitope definition of T cell responses against SARS 3a (the largest accessory protein and unique to the SARS-CoV) (14 16 and NP proteins is usually lacking. Here we analyzed the presence and function of SARS memory T cell response at 6 years postinfection. We defined a dominant SARS-specific T cell response generally detectable in Asian individuals and isolated its SARS-specific T cell receptors. We then demonstrated the possibility Ginsenoside Rh2 to generate SARS-specific T cells from lymphocytes of healthy uninfected individuals through T-cell-receptor (TCR) gene transfer. TCR gene transfer has emerged in several studies as a way to develop cell-based therapy for chronic viral diseases such as hepatitis C and B (8 31 and malignancies such as melanoma (21). In addition adoptive transfer of virus-specific T cells can also safeguard subjects that undergo immunosuppressive treatment from human cytomegalovirus (HCMV) or Epstein-Barr computer virus (EBV) reactivation (4 7 Thus the identification of SARS epitopes and production of SARS-specific TCR-redirected T cells can provide prophylactic or therapeutic opportunities against this infection. MATERIALS AND METHODS Subjects. Sixteen recovered SARS individuals (6 years postinfection) were enrolled in the present study from your Singapore General Hospital (Singapore). All of the participants had been diagnosed as having SARS based on clinical examination during the period from March to May 2003 according to the World Health Organization’s definition of SARS (30). The diagnosis was further confirmed by serological detection of SARS-CoV-specific antibodies detected by enzyme-linked immunosorbent assay and/or reverse transcription-PCR for SAR-CoV mRNA. Five normal subjects without any contact history with SARS patients were used as negative controls. This study was approved by the Centralized Institutional Review Table of the Singapore Health Services Pte Ltd. (Singapore). Isolation of PBMC and growth of SARS-specific T.