T Cell Response in Tuberculosis-Infected Patients Vaccinated against COVID-19

Abstract

Many studies have focused on SARS-CoV-2 and Mycobacterium tuberculosis (Mtb) co-infection consequences. However, after a vaccination plan against COVID-19, the cases of severe disease and death are consistently controlled, although cases of asymptomatic and mild COVID-19 still happen together with tuberculosis (TB) cases. Thus, in this context, we sought to compare the T cell response of COVID-19-non-vaccinated and -vaccinated patients with active tuberculosis exposed to SARS-CoV-2 antigens. Flow cytometry was used to analyze activation markers (i.e., CD69 and CD137) and cytokines (IFN-γ, TNFα, IL-17, and IL-10) levels in CD4⁺ and CD8⁺ T cells upon exposure to SARS-CoV-2 peptides. The data obtained showed that CD8⁺ T cells from non-vaccinated TB patients present a high frequency of CD69 and TNF-α after viral challenge compared to vaccinated TB donors. Conversely, CD4⁺ T cells from vaccinated TB patients show a high frequency of IL-10 after spike peptide stimulus compared to non-vaccinated patients. No differences were observed in the other parameters analyzed. The results suggest that this reduced immune balance in coinfected individuals may have consequences for pathogen control, necessitating further research to understand its impact on clinical outcomes after COVID-19 vaccination in those with concurrent SARS-CoV-2 and Mtb infections.

Keywords: immune response; infection; lymphocytes; vaccines.

Figure 1

Profile of activation markers in T cells. (a) CD69 and (b) CD137 expression in CD4⁺ T cells. (c) CD69 and (d) CD137 expression in CD8⁺ T cells. Graphs are expressed as mean ± standard error (SEM). * p < 0.05, **** p < 0.0001, ^# p < 0.05 medium vs. SEB within each group, ^b p < 0.05 NTB medium vs. HC medium, ^§ p < 0.05 HC vs. NTB; HC = healthy control (n = 9); NTB = non-vaccinated with active tuberculosis (n = 3); VTB = vaccinated with active tuberculosis (n = 8). PS = Pool Spike Cov-2; PT = Pool CoV-2; SEB = staphylococcal enterotoxin B.

Figure 2

Profile of cytokines in CD4⁺ T cells. (a) TNF-α, (b) IFN-γ, (c) IL-17, and (d) IL-10. Graphs are expressed as mean ± standard error (SEM). * p < 0.05, **** p < 0.0001, ^§ p < 0.05 HC vs. NTB; HC = healthy control (n = 9); NTB = non-vaccinated with active tuberculosis (n = 3); VTB = vaccinated with active tuberculosis (n = 8). PS = Pool Spike Cov-2; PT = Pool CoV-2; SEB = staphylococcal enterotoxin B.

Figure 3

Profile of cytokines in CD8⁺ T cells. (a) TNF-α, (b) IFN-γ, (c) IL-17, (d) IL-10. Graphs are expressed as mean ± standard error (SEM). ** p < 0.01, ^a p < 0.05 HC PT vs. HC medium, ^§ p < 0.05 HC vs. NTB; HC = healthy control (n = 9); NTB = non-vaccinated with active tuberculosis (n = 3); VTB = vaccinated with active tuberculosis (n = 8). PS = Pool Spike Cov-2; PT = Pool CoV-2; SEB = staphylococcal enterotoxin B.

Figure 4

Radar charts of immune profile of CD4⁺ and CD8⁺ T cells. HC = healthy control (n = 9); NTB = non-vaccinated with active tuberculosis (n = 3); VTB = vaccinated with active tuberculosis (n = 8). PS = Pool Spike Cov-2; PT = Pool CoV-2.