Sergio, Díaz-Fernández, Raquel, Villar-Hernández, Zoran, Stojanovic, Marco, Fernández, Maria Luiza De Souza, Galvão, Guillermo, Tolosa, Adrián, Sánchez-Montalva, Jorge, Abad, María Ángeles, Jiménez-Fuentes, Guillem, Safont, Iris, Romero, Josefina, Sabrià, Cristina, Prat, Jose, Domínguez, Irene, Latorre, Institut Català de la Salut, [Díaz-Fernández S, Villar-Hernández R] Institut d’Investigació Germans Trias i Pujol, Barcelona, Spain. CIBER Enfermedades Respiratorias, CIBERES, Instituto de Salud Carlos III, Madrid, Spain. Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Spain. [Stojanovic Z] CIBER Enfermedades Respiratorias, CIBERES, Instituto de Salud Carlos III, Madrid, Spain. Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Spain. Servei de Pneumologia, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain. [Fernández M] Plataforma de Citometría, Institut d’Investigació Germans Trias i Pujol, Barcelona, Spain. [De Souza Galvão ML, Jiménez-Fuentes MÁ] Unitat de Tuberculosi, Drassanes - Vall d’Hebron Hospital Universitari, Barcelona, Spain. [Tolosa G] Universidad de la Frontera (UFRO), Temuco, Chile. [Sánchez-Montalva A] Servei de Malalties Infeccioses, Vall d’Hebron Hospital Universitari, Barcelona, Spain. PROSICS Barcelona. Universitat Autònoma de Barcelona, Bellaterra, Spain. Grupo de Estudio de micobacterias (GEIM), Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC), Madrid, Spain, and Vall d'Hebron Barcelona Hospital Campus
Mycobacterium tuberculosis; T-cells; Immune response Tuberculosis micobacteriana; Células T; Respuesta inmune Tuberculosi micobacteriana; Cèl·lules T; Resposta immune Background: Current blood-based diagnostic tools for TB are insufficient to properly characterize the distinct stages of TB, from the latent infection (LTBI) to its active form (aTB); nor can they assess treatment efficacy. Several immune cell biomarkers have been proposed as potential candidates for the development of improved diagnostic tools. Objective: To compare the capacity of CD27, HLA-DR, CD38 and Ki-67 markers to characterize LTBI, active TB and patients who ended treatment and resolved TB. Methods: Blood was collected from 45 patients defined according to clinical and microbiological criteria as: LTBI, aTB with less than 1 month of treatment and aTB after completing treatment. Peripheral blood mononuclear cells were stimulated with ESAT-6/CFP-10 or PPD antigens and acquired for flow cytometry after labelling with conjugated antibodies against CD3, CD4, CD8, CD27, IFN-γ, TNF-α, CD38, HLA-DR, and Ki-67. Conventional and multiparametric analyses were done with FlowJo and OMIQ, respectively. Results: The expression of CD27, CD38, HLA-DR and Ki-67 markers was analyzed in CD4+ T-cells producing IFN-γ and/or TNF-α cytokines after ESAT-6/CFP-10 or PPD stimulation. Within antigen-responsive CD4+ T-cells, CD27− and CD38+ (ESAT-6/CFP-10-specific), and HLA-DR+ and Ki-67+ (PPD- and ESAT-6/CFP-10-specific) populations were significantly increased in aTB compared to LTBI. Ki-67 demonstrated the best discriminative performance as evaluated by ROC analyses (AUC > 0.9 after PPD stimulation). Data also points to a significant change in the expression of CD38 (ESAT-6/CFP-10-specific) and Ki-67 (PPD- and ESAT-6/CFP-10-specific) after ending the anti-TB treatment regimen. Furthermore, ratio based on the CD27 median fluorescence intensity in CD4+ T-cells over Mtb-specific CD4+ T-cells showed a positive association with aTB over LTBI (ESAT-6/CFP-10-specific). Additionally, multiparametric FlowSOM analyses revealed an increase in CD27 cell clusters and a decrease in HLA-DR cell clusters within Mtb-specific populations after the end of treatment. Conclusion: Our study independently confirms that CD27−, CD38+, HLA-DR+ and Ki-67+ populations on Mtb-specific CD4+ T-cells are increased during active TB disease. Multiparametric analyses unbiasedly identify clusters based on CD27 or HLA-DR whose abundance can be related to treatment efficacy. Further studies are necessary to pinpoint the convergence between conventional and multiparametric approaches. This research was supported by a grant from the Instituto de Salud Carlos III (PI18/00411, PI19/01408 and CP20/00070), integrated in the Plan Nacional de I + D + I and cofunded by the ISCIII Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (FEDER); a grant from the Sociedad Española de Neumología y Cirugía Torácica (project 25/2016; SEPAR; Barcelona, Spain); and from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie grant agreement no. 823854 (INNOVA4TB). JD and IL are researchers from the Miguel Servet programme. AS-M is supported by a Juan Rodés (JR18/00022) postdoctoral fellowship from ISCIII.