The BTK inhibitor ibrutinib impairs the innate immune response against Mycobacterium tuberculosis mediated by macrophages and γδ T cell.

COLADO ANA; MELANIE GENOULA; DENISE KVIATCOVSY; PODAZA ENRIQUE; RISNIK DENISE; JOSE LUIS MARIN FRANCO; COUGOULE CELINE; ISABELLE MARIDONNEAU-PARINI; JANCIC CAROLINA; GIORDANO MIRTA; SASIAIN MARÍA DEL CARMEN; GAMBERALE ROMINA; BALBOA LUCIANA; BORGE MERCEDES

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Ibrutinib is an oral inhibitor of the Bruton´s Tyrosine Kinase (Btk) recently approved for the treatment of Chronic Lymphocytic Leukemia (CLL)´s patients. We have previously found that ibrutinib affected macrophage functions including M1 polarization and TNF-α secretion in response to M. tuberculosis (Mtb). Considering that ibrutinib is now being introduced in countries with high incidence rates of tuberculosis such as Argentina, in this work we aimed to extend the study on the effect of ibrutinib on the immune response to Mtb mediated by macrophages and gamma delta (gd) T cells. Macrophages were differentiated by culturing monocytes with M-CSF for 7 days. TNFα, IL-8 and IL-10 secretion were measured by ELISA after macrophage stimulation with irradiated Mtb, Pam3CK or LPS for 24h. Phosphorilation of p65 of NFkB was evaluated by Western blot. Phagocytosis of Mtb-FITC by macrophages was evaluated by flow cytometry. Bacillary loads were determined by colony-forming units assays. gd T cells were purified from PBMC by using MACS and stimulated with irradiated Mtb for 24h. IFN-γ was evaluated by ELISA and CD69 expression by flow cytometry. Statistical significance was determined using the non parametric Friedman test followed by the Dunn?s post test.We found that ibrutinib significantly reduced the release of TNF-α, IL-10 and IL-8, being the production of TNF-α severely affected even at low concentrations of the drug, while IL-10 and IL-8 secretion was only affected at 3 µM (n=10, p˂0.05). We then evaluated the effect of ibrutinib on the phosphorilation of p65 of the NFkB pathway which is involved in cytokine secretion in response to Mtb and found that phospho-p65 was diminished by ibrutinib (n=5, p˂0.05). Moreover, we found that ibrutinib impaired TNF-α secretion by macrophages in response to LPS (TLR4 agonist) and Pam3CK (TLR2 agonist) (n=10, p˂0.05). Then we evaluate the effect of ibrutinib on Mtb uptake by macrophages and on the intracellular growth of the bacteria. We found ?.. Although ibrutinib did not affect Mtb phagocytosis (n=10) .preliminary results showed a slight increase in the bacillary loads obtained from ibrutinib-treated macrophages at day 3 and 6 post-infection. CD69 upregulation and IFN-γ secretion was also impaired in gdT cells in response to Mtb.Our results suggest that the innate-immune response to Mtb might be compromised in ibrutinib-treated patients. Thus, increased awareness should be taken in ibrutinib-treated patients especially from countries with high incidence rates of tuberculosis.