Attenuating cytotoxic T lymphocytes-mediated immune disorders by nucleic acid-based agents targeting CD8 and granulysin

• Main Authors: Chuang-Wei Wang, 王壯維
• Other Authors: Shuen-Iu Hung
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/93029218599703086567

博士 === 國立陽明大學 === 藥理學研究所 === 101 === Background: Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) and graft-versus-host disease (GVHD) are distinct immune reactions elicited by drugs or allogeneic antigens; however, they share patho-mechanism with the activation of cytotoxic T lymphocytes (CTLs). CTLs produce cytotoxic proteins, cytokines, chemokines, or immune alarmin, such as granulysin (GNLY), leading to the extensive tissue damage and systemic inflammation in SJS/TEN or GVHD. Currently, there is no effective therapeutic agent specific for CTLs-mediated immune disorders. Objectives: By targeting GNLY+ CTLs, we aimed to develop nucleic acid-based agent consisted of an anti-CD8 aptamer with GNLY siRNA. Methods: We performed “systematic evolution of ligands by exponential enrichment (SELEX)” to select and identify effective anti-CD8 aptamers. We developed aptamer-siRNA chimera using a 'sticky bridge' method by conjugating the aptamer with siRNA. We analyzed the inhibitory effects of aptamer-siRNA chimera on CTLs response in SJS/TEN and GVHD. Results: We identified a novel DNA aptamer (CD8AP17s) targeting CTLs. The CD8AP17s could be specifically internalized into human CTLs. We generated the CD8AP17s aptamer-GNLY siRNA chimera which showed more than 79% inhibitory effect on the production of GNLY by drugs/allo-antigens activated T cells. The CD8AP17s aptamer-GNLY siRNA chimera decreased the cytotoxicity in both the in vitro models of SJS/TEN (elicited by drug-specific antigen) or GVHD (by allogeneic antigens). Conclusions: Our results identified a new nucleic acid-based agent (CD8 aptamer-GNLY siRNA chimera) which can significantly inhibit the CTLs-mediated drug hypersensitivity such as SJS/TEN as well as the alloreactivity in GVHD. This study provides a novel therapeutic strategy for CTLs-mediated immune disorders.