发布: 2017年06月05日第7卷第11期 DOI: 10.21769/BioProtoc.2307 浏览次数: 17304
评审: Andrea PuharGuangzhi ZhangAnonymous reviewer(s)
相关实验方案
HS-GC-MS 方法用于 DSS 诱导性结肠炎模型中 IBD 动态变化的诊断
Olga Yu. Shagaleeva [...] Natalya B. Zakharzhevskaya
2025年03月20日 1667 阅读
Abstract
Antigen presenting cells (APC) are able to process and present to T cells antigens from different origins. This mechanism is highly regulated, in particular by Patter Recognition Receptor (PRR) signals. Here, I detail a protocol designed to assess in vitro the capacity of APC to present antigens derived from bacteria, apoptotic and infected apoptotic cells.
Keywords: Antigen presentation (抗原呈递)Background
T cell lymphocytes express on their surface the T cell receptor (TCR), which allows the recognition of cellular (self) or microbial (non-self) antigens that are processed and presented as peptides bound to the major histocompatibility complex (MHC) molecules by antigen presenting cells (APC). APC are able to process antigens and to present them to T cells, and MHC-TCR interactions are critical steps for T cell activation during both infectious and autoimmune responses.
Previous works have described a mechanism of regulation of antigen presentation based on the stimulation of Pattern Recognition Receptors (PRRs), such as toll-like receptors (TLRs) (Blander and Medzhitov, 2004 and 2006). Indeed, TLR signals specifically from phagosomes containing microbial pathogens favor the presentation of non-self-antigens within MHC-II molecules. On the other hand, self-antigens generated after phagocytosis of apoptotic cells are directed to lysosomal degradation because of the absence of TLR stimuli. However, the segregation of self and non-self-antigens does not occur when both derive from infected apoptotic cells and are simultaneously carried by the same phagosome, which is optimally tailored by TLR signals for antigen presentation. Such mechanism of phagosome maturation and antigen presentation upon TLR triggering has been demonstrated in vitro using bone marrow derived dendritic cells (BMDC) and apoptotic murine B cells–either primary or A20 B cell line–previously incubated with the TLR4 ligand lipopolysaccharide (LPS), which is internalized by B cells and mimics bacterial infection (Blander and Medzhitov, 2004 and 2006; Campisi et al., 2016). Despite its elegance, this experimental system fails to reproduce bacterial invasion of the eukaryotic target cell. Furthermore, no T cell traceable antigens are present in the apoptotic cargo that internalized LPS.
I developed an in vitro alternative protocol where A20 cells are directly infected by the cell invasive bacteria Listeria monocytogenes expressing a recombinant antigen, allowing to assess the capacity of BMDC to present self and non-self-antigens derived from the same infected apoptotic cargo (Campisi et al., 2016).
Materials and Reagents
Equipment
Software
Procedure
文章信息
版权信息
© 2017 The Authors; exclusive licensee Bio-protocol LLC.
如何引用
Campisi, L. (2017). In vitro Antigen-presentation Assay for Self- and Microbial-derived Antigens. Bio-protocol 7(11): e2307. DOI: 10.21769/BioProtoc.2307.
分类
免疫学 > 免疫细胞功能 > 抗原特异反应
微生物学 > 微生物-宿主相互作用 > 细菌
细胞生物学 > 细胞信号传导 > 胞内信号传导
您对这篇实验方法有问题吗?
在此处发布您的问题,我们将邀请本文作者来回答。同时,我们会将您的问题发布到Bio-protocol Exchange,以便寻求社区成员的帮助。
提问指南
+ 问题描述
写下详细的问题描述,包括所有有助于他人回答您问题的信息(例如实验过程、条件和相关图像等)。
Share
Bluesky
X
Copy link