PARTICIPATION OF INTERFERON GAMMA IN THE LEUKOCYTE RECRUITMENT TO THE CENTRAL NERVOUS SYSTEM IN LPS-INDUCED NEUROINFLAMMATION

MANZONE RODRIGUEZ CLARISA; PERALTA RAMOS JAVIER MARÍA; BÁEZ NATALIA SOLEDAD; RODRÍGUEZ CECILIA MARÍA; ARROYO DANIELA SOLEDAD ; IRIBARREN PABLO

Congreso; Reunión Anual de Sociedades de Biociencias 2021; 2021

la Sociedad Argentina de Inmunología (SAI), Sociedad Argentina de Investigación Clínica (SAIC) y la Asociación Argentina de Farmacología Experimental (AAFE)

PARTICIPATION OF INTERFERON GAMMA IN THE LEUKOCYTE RECRUITMENT TO THE CENTRAL NERVOUS SYSTEM IN LPS-INDUCED NEUROINFLAMMATIONClarisa Mazone-Rodriguez 1, Javier Peralta Ramos 2, Natalia Soledad Báez3, Cecilia María Rodríguez 3, Daniela Soledad Arroyo3 and Pablo Iribarren 1.1CIBICI-CONICET, Fac. de Ciencias. Químicas, UNC. Córdoba, Argentina,2Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel, 3Laboratorio de Biología Molecular y Citometría de Flujo del servicio de Oncología y Hematología, Hospital Nacional de Clínicas, Fac. de Medicina, UNC. E-mail: cmanzone@fcq.unc.edu.arIntroduction: microglial cells are brain immune components in charge of maintaining the homeostasis and protecting the brain parenchyma against injuries.Peripheral leucocytes are recruited to the central nervous system (CNS) in response to cytokines and chemokines during neuroinflammatory processes. If the response is not properly controlled, that recruitment could be harmful and may contribute to the progression of neuroinflammation.We previously found that systemic lipopolysaccharide (LPS) challenge induced glial activation and recruitment of CD45hi leukocytes to brain blood vessels, in circumventricular organs. During systemic inflammation interferon-gamma (IFN-γ) is induced and participate in the inflammation observed in different target organs. However, little is known about the impact of this cytokine in the CNS immune cells during this process. Methods: we injected PBS or LPS (1.6 mg/kg, i.p.) to wild type (WT) C57BL/6 strain and IFN-γ knockout (KO) mice (n=4). After perfusion, we processed the brains to isolate the immune cells for staining and measuring them by flow cytometry. We performed conventional and high dimensional flow cytometry analysis to study the different immune cells populations.Results: LPS systemic stimuli increased the monocyte recruitment to WT mice brains compared to PBS-injected control group (p<0.05). However, this effect was not observed in the IFN-γ KO mice (p NS), indicating that the presence of type II interferon participates in the response that results in the arrival of monocytes to the brain. Our preliminary results also showed increased lymphocytes recruitment to the brains of LPS-stimulated WT mice, compared to controls (p<0.05). Nevertheless, that increase was impaired in the absence of IFN-γ (p NS). Conclusion: during mice systemic inflammation, leukocyte recruitment to CNS take place in a type II interferon-dependent manner, suggesting that this cytokine might be an important mediator of neuroinflammatory responses. Keywords: neuroinflammation, microglia, monocytes, type II interferon, LPS