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bioRxiv · 10.1101/2025.05.28.656614

CD39 REGULATES P2RX7-MEDIATED LUNG NECROTIC LESIONS IN SEVERE EXPERIMENTAL TUBERCULOSIS

Abstract

Tuberculosis induces diverse lesions, such as necrotic pneumonia, contributing to disease progression and transmission. Despite advances in understanding the role of ATP-gated P2RX7 ion channels in developing severe forms of tuberculosis, the regulation of this important signaling pathway remains unclear. Herein, we show that the ectonucleotidase CD39 plays an essential regulatory role in TB progression by preventing lung tissue damage, bacterial dissemination, and excessive inflammatory responses. Mechanistically, through its enzymatic activity on the cellular surface, CD39 protects infected macrophages from undergoing necrotic death mediated by P2RX7 activation. We proposed that by protecting macrophages from P2RX7-mediated cell death and bacterial dissemination, CD39 prevents the development of necrotic lesions. Altogether, these findings uncover a significant role for CD39 as an essential component of the molecular regulation underlying the development of severe tuberculosis. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=107 SRC="FIGDIR/small/656614v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@1dc7320org.highwire.dtl.DTLVardef@a4202org.highwire.dtl.DTLVardef@173bb62org.highwire.dtl.DTLVardef@1132f0f_HPS_FORMAT_FIGEXP M_FIG C_FIG BriefIn tuberculosis, necrotic granuloma-like structures release extracellular ATP (eATP), which triggers P2RX7-mediated immune cell death. CD39 degrades eATP, preventing P2RX7 activation and promoting macrophage survival, thereby limiting inflammation, tissue damage, and bacterial dissemination.

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BibTeXRIS

Almeida-Santos, G., Santiago-Carvalho, I., Almeida, F. M., Bomfim, C. C. B., Santos e Silva, J. C., Cantarini, D. G., Silva, C. R., Ribeiro, M. S., Macedo, B. d. G., Raeder, P. H. L., Teixeira-Xavier Junior, J., Alvarez, J. M., Hirata, M. H., Coutinho-Silva, R., Robson, S. C., Amaral, E. P., Lasunskaia, E., Lima, M. R. D. I.. 2025-05-29. CD39 REGULATES P2RX7-MEDIATED LUNG NECROTIC LESIONS IN SEVERE EXPERIMENTAL TUBERCULOSIS. https://doi.org/10.1101/2025.05.28.656614

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