Beveridge Natalie E R, Fletcher Helen A, Hughes Jane, Pathan Ansar A, Scriba Thomas J, Minassian Angela, Sander Clare R, Whelan Kathryn T, Dockrell Hazel M, Hill Adrian V S, Hanekom Willem A, McShane Helen
Jenner Institute, Old Road Campus Research Building, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7DQ, UK.
Tuberculosis (Edinb). 2008 Nov;88(6):631-40. doi: 10.1016/j.tube.2008.06.005. Epub 2008 Sep 17.
Interferon gamma (IFNgamma) is a critical component of the pro-inflammatory immune response that provides protection against Mycobacterium tuberculosis. In the absence of an immunological correlate of protection, antigen-specific production of IFNgamma is a commonly used marker of a protective immune response. To facilitate the evaluation of tuberculosis candidate vaccines three different IFNgamma detection methods were compared. The cultured whole blood ELISA, ex vivo IFNgamma ELISpot and whole blood ex vivo intracellular cytokine staining (ICS) assays were performed head-to-head during a Phase I clinical trial using the candidate vaccine MVA85A. Whilst all three assays detected significant increases in IFNgamma production immediately following vaccination, distinctions between the assays were apparent. Higher baseline IFNgamma responses were detected using the cultured whole blood ELISA, whereas the ex vivo ELISpot assay was the most sensitive in detecting long-term (52 weeks) post-vaccination responses. The whole blood ex vivo ICS assay provided novel information by dissecting the IFNgamma response into responding CD4, CD8 and gamma/delta T cell subsets. Future tuberculosis vaccine trials and immunology studies should ideally include a combination of ex vivo and cultured assays to ensure a thorough and multifaceted evaluation of the immune response is achieved.
γ干扰素（IFNγ）是促炎性免疫反应的关键组成部分，可提供针对结核分枝杆菌的保护作用。在缺乏保护的免疫学相关指标的情况下，抗原特异性IFNγ的产生是保护性免疫反应常用的标志物。为便于评估结核病候选疫苗，对三种不同的IFNγ检测方法进行了比较。在使用候选疫苗MVA85A的I期临床试验中，对培养全血ELISA、离体IFNγ ELISpot和全血离体细胞内细胞因子染色（ICS）检测进行了直接比较。虽然所有三种检测方法都在接种疫苗后立即检测到IFNγ产生的显著增加，但各检测方法之间的差异很明显。使用培养全血ELISA检测到更高的基线IFNγ反应，而离体ELISpot检测在检测接种疫苗后的长期（52周）反应方面最敏感。全血离体ICS检测通过将IFNγ反应分解为反应性CD4、CD8和γ/δ T细胞亚群提供了新信息。未来的结核病疫苗试验和免疫学研究理想情况下应包括离体检测和培养检测的组合，以确保对免疫反应进行全面和多方面的评估。
