Figure 4. Cell-intrinsic P2RX7 is required for CD4⁺ T cell lung parenchymal establishment in response to severe TB.

CD4-KO (Cd4^−/−) mice were infected with ~100 CFU of the Mbv MP287 strain. On day 5 p.i., splenic CD4⁺ T cells (1 × 10⁶) from WT (CD45.1⁺) and P2RX7-KO (CD45.2⁺; P2rx7^−/−) mice were co-transferred (1:1) to infected CD4-KO mice.

(A) Experimental protocol (BioRender.com).

(B) Left: flow-cytometry plots of CD45.1 and CD45.2 on CD45i.v.⁺ and CD45i.v.⁻ CD44⁺CD4⁺ T cells. Right: average frequencies and numbers of CD45i.v.⁺ and CD45i.v.⁻ CD44⁺CD4⁺ T cells.

(C) Left: flow-cytometry plots of CD44 and T-bet on CD45i.v.⁻CD4⁺ T cells. Right: average frequencies and numbers of lung intravascular and parenchymal T-bet⁺CD45i.v.⁻CD44⁺CD4⁺ T cells.

(D) Left: flow-cytometry plots of CD44 and IFN-γ on CD45i.v.⁻CD4⁺ T cells. Right: average frequencies and numbers of lung intravascular and parenchymal IFN-γ⁺CD45i.v.⁻CD44⁺CD4⁺ T cells.

(E) Left: histograms showing Ki-67 on CD45i.v.⁻CD44⁺CD4⁺ T cells. Right: average frequencies of CD45i.v.⁻Ki-67⁺CD4⁺ T cells.

(F) Left: histograms of KLRG1, CX3CR1, CD69 and CXCR3 in CD45i.v.⁻CD44⁺CD4⁺ T cells. Right: average frequencies of KLRG1⁺, CX3CR1⁺, CD69⁺ and CXCR3⁺ CD45i.v.⁻CD44⁺CD4⁺ T cells.

(G) Left: flow cytometry plots of CD45.1 and CD45.2 on CD45i.v.⁻CD44⁺CD4⁺T cells in the medLNs. Right: average frequencies of CD45i.v.⁻CD44⁺CD4⁺T cells in medLNs.

(H) Left: histograms of KLRG1, CX3CR1, CD69 and CXCR3 in CD45i.v.⁻CD44⁺CD4⁺ T cells in medLNs. Right: average frequencies of KLRG1⁺, CX3CR1⁺, CD69⁺ and CXCR3⁺ CD45i.v.⁻CD44⁺CD4⁺ T cells in medLNs.

(I) Average frequency of CD44⁺CD4⁺ T cells in the blood over the weeks after infection.

Data from two independent experiments, n = 5/experimental group per experiment. Data shown as means ± SD. *p < 0.05, **p < 0.01, ***p < 0.001, one-way ANOVA (Tukey post tests) (B) or unpaired t tests (C–I).