L’anémie est un symptôme fréquent chez les patients atteints de cancer. La libération de la cytokine pro-inflammatoire TNFα, un inhibiteur connu de l’érythropoïèse, en est l’une des causes. L’érythropoïèse est un processus nécessitant l’arrêt de la prolifération et l’autophagie. Les résultats précédents ont montré que le TNFα inhibe l’expression des marqueurs érythroïdes et module l’expression de facteurs de transcription (FT) hématopoïétiques. Notre objectif est d’étudier l’implication de la voie TNFα/sphingomyélinase (SMase)/céramide dans l’inhibition de l’érythropoïèse en utilisant des cellules souches hématopoïétiques CD34+ induites à se différencier par l’érythropoïétine recombinante (Epo). Par l’utilisation de céramides exogènes, de SMase bactérienne et d’inhibiteurs de SMases, nous montrons l’implication de la voie SMase/céramide dans l’inhibition de l’expression des marqueurs érythroïdes mais également dans l’induction de la différenciation myéloïde avec une augmentation de l’expression du CD11b. Cet effet sur la différenciation est corrélé à la modulation du réseau FT/miR impliquant GATA-1, GATA-2 et PU.1 et les miR-144, 451, 155, 146a et 223. De plus, l’analyse par microscopie électronique à transmission, l’absence de formation de punctae GFP-LC3 et l’accumulation de SQSTM1/p62 montrent que le TNFα et les céramides inhibent l’autophagie induite par l’Epo. L’analyse des protéines impliquées dans la régulation de l’autophagie montre que le TNFα et les céramides activent mTOR. Son implication est confirmée par l’utilisation de rapamycine et l’inhibition de ULK1 et Atg13. De plus, le TNFα et les céramides inhibent l’expression de bécline 1 et de la formation du complexe Atg5-Atg12. Ces résultats démontrent que la voie TNFα/SMase/céramide joue un rôle dans l’homéostasie hématopoïétique par l’inhibition de l’érythropoïèse au profit de la myélopoïèse, en impactant les réseaux de régulation FT/miR et le processus d’autophagie / Anemia is a common symptom in cancer patients. It can be caused by the release of pro-inflammatory cytokines such as TNFα, a known inhibitor of erythropoiesis. Erythropoiesis involves proliferation arrest and autophagy. Our previous studies showed that TNFα inhibits the expression of erythroid markers as well as hematopoietic transcription factors (TF) expression. The aim is to study the involvement of TNFα/sphingomyelinase (SMase)/ceramide pathway in erythropoiesis inhibition using recombinant erythropoietin (Epo)-induced CD34+ hematopoietic stem cells. Using exogenous ceramides, a bacterial SMase and sphingomyelinase inhibitors, we show the involvement of SMase/ceramide pathway in the inhibition of erythroid markers as well as the induction of myeloid differentiation as shown by the increase in CD11b expression. This effect is correlated to the modulation of the TF/miR network involving GATA-1, GATA-2 and PU.1 as well as miR-144, 451, 155, 146a and 223. We show that TNFα and ceramides inhibit Epo-induced autophagy through transmission electron microscopy analysis, the absence of GFP-LC3 punctae formation and SQSTM1/p62 accumulation. Analysis of proteins involved in autophagy regulation showed that TNFα and ceramides activate mTOR, which is confirmed using rapamycin as well as the inhibition of ULK1 and Atg13. Moreover, TNFα and ceramides inhibit Beclin 1 expression and Atg5-Atg12 complex formation. These results demonstrate the role of TNFα/SMase/ceramide pathway in hematopoietic homeostasis through an erythropoiesis-myelopoiesis switch resulting from perturbation of TF/miR network and autophagy

Macrophages are involved in many aspects of both the innate and acquired immunity, and participate in tissue homeostasis, bone remodelling, wound healing, and tissue repair. When their function becomes dysregulated, they contribute to the initiation and progression of inflammatory diseases. Genes expressed in activated macrophages are likely to play an important role in inflammation and/or immunity. One family of genes that is highly expressed in activated macrophages is the Schlafen (Slfn) gene family. Given that very little is known about the function of this family, particularly in macrophages, this study focused on the regulation and function of one family member, namely Slfn-4. The transcriptional regulation of Slfn-4 was characterised in murine macrophages. The expression of Slfn-4 was transiently down regulated during macrophage differentiation and dramatically up regulated in response to activation signals including lipopolysaccharide (LPS) and dsRNA Poly(I:C). A potential association with inflammation was further suggested by the enhanced expression of Slfn-4 in a mouse model of rheumatoid arthritis. Further investigations into transcriptional regulation of Slfn-4 revealed that it belongs to the subset of genes that are type I interferon (IFN)-inducible. This finding is consistent with the predicted transcription factor binding sites in the putative promoter of Slfn-4, and suggests a role for Slfn-4 in the antiviral response. To gain further insight into the function of Slfn-4 in macrophage biology, in vitro over-expression approaches were undertaken and its cellular localisation in macrophages was characterised. In resting and activated macrophages, Slfn-4 exhibited a cytoplasmic and strong perinuclear localisation. Additional studies were carried out to investigate the in vivo biology of Slfn-4 in macrophages. For this purpose, the Csf1r-GAL4VP16/UAS-ECFP (referred to as “MacBlue”) transgenic mouse line was first characterised. Enhanced cyan fluorescent (ECFP) reporter expression in the MacBlue transgenic mice was specifically detected in cells of the mononuclear phagocyte system during embryonic development and adulthood. The MacBlue transgenic mouse line was next used to drive expression of Slfn-4 in cells of the myeloid lineage in vivo, and to examine the phenotype of this line. Specific over-expression of Slfn-4 in cells of the myeloid lineage in vivo altered the percentage of peripheral blood monocytes and caused extramedullary hematopoiesis. In summary, this thesis demonstrated that Slfn-4 expression is dynamically regulated during macrophage differentiation and activation, and the enforced Slfn-4 over-expression in cells of the myeloid lineage perturbs normal monocyte/macrophage development.

京都大学 / 新制・課程博士 / 博士(医科学) / 甲第23472号 / 医科博第131号 / 新制||医科||9(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 滝田 順子, 教授 髙折 晃史, 教授 江藤 浩之 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Proper development and activation of cells of the myeloid lineage are critical for supporting innate immunity. This myelopoiesis is orchestrated by interdependent interactions between cytokine receptors, transcription factors and, as recently described, microRNAs (miRNAs). miRNAs contribute to normal and dysregulated myelopoiesis. Alterations in myelopoiesis underlie myeloid-derived suppressor cell (MDSC) expansion, a poorly understood heterogeneous population of immature and suppressive myeloid cells that expand in nearly all diseases where inflammation exists. MDSCs associated with inflammation often have immunosuppressive properties, but molecular mechanisms responsible for MDSC expansion are unclear. Emerging data implicate miRNAs in MDSC expansion. This review focuses on miRNAs that contribute to myeloid lineage differentiation and maturation under physiological conditions, and introduces the concept that altered miRNA expression my underlie expansion and accumulation of MDSCs. We divide our miRNAs into those with potential to promote MDSC expansion and two with known direct links to MDSC expansion, miR-223 and miR-494.

Innate immunity operates independently of prior exposure to pathogens. There are several signal transduction pathways that play a key role in inflammatory and immune responses. Critical signaling cascade in the interest of my research is type-1 interferon (IFN) signaling pathway in response to infection with Salmonella Typhimurium (ST). The role of type-I interferons is well established in the context of a viral infection; however, their role in bacterial infections is not clear. In my thesis I aimed to understand the role of type-1 IFNs in bacterial pathogenesis, and scrutinize the mechanism adopted by various components of type-1 IFN signaling, especially ISGF3 complex in response to Salmonella Typhimurium. My results indicate that type-I IFN signaling is detrimental to host survival. I further investigated the mechanism through which type-1 IFN signaling results in host susceptibility against Salmonella. My results indicated that the three transcription factors downstream of IFNAR1 have different impacts in mounting an innate immune response against ST. IRF9 and STAT2 promote susceptibility against ST whereas STAT1 through IFNAR1-signaling, promotes enhanced expression of pro inflammatory cytokines and protection against ST. I also observed that the monocytes/macrophages lineage in Ifnar1⁻ᐟ⁻ mice is responsible for conferring the enhanced resistance against ST. Furthermore, my work determined that expression of type-I IFN signaling compromises the fitness of macrophages by reducing mitochondrial respiration, glycolysis and myelopoiesis.

INTRODUCTION: Previous studies have shown that osteocytes, the matrix-embedded cells in bone, control bone modeling and remodeling through direct contact with adjacent cells and via secreted factors that can reach cells in the bone marrow microenvironment (BMM). Osteocytes express several receptors including G protein-coupled receptors (GPCRs) and mice lacking the stimulatory subunit of G-proteins (Gsα) in osteocytes have abnormal myelopoiesis, skeletal abnormalities and reduced adipose tissue. This study aimed at evaluating the effects of osteocyte-secreted factors on myeloid cell proliferation and differentiation in vitro. To investigate cross-talk between osteocytes and the BMM, we established osteocytic cell lines lacking Gsα expression to study the molecular mechanisms by which osteocytes control myeloid cell proliferation and differentiation. METHODS: CRISPR/Cas9 was used to knockout Gsα in the osteocytic cell line Ocy454. Conditioned media (CM) from differentiated Ocy-GsαCtrl and Ocy-GsαKO cells were used to treat myeloid cells and bone marrow mononuclear cells (BMNCs) isolated from long bones of 6-8-week-old C57/BL6 mice. BMNCs were cultured with Macrophage Colony Stimulating Factor (M-CSF), Receptor Activator of Nuclear Factor Kappa β Ligand (RANKL) to induce osteoclast differentiation. Proliferation, TRAP staining, TRAP activity, resorption pit assay, F-actin ring formation and mRNA expression were used to evaluate cell proliferation, differentiation and function of the induced osteoclasts. Proteomics analysis of CM was performed to identify osteocyte-secreted factors capable of controlling myelopoiesis and osteoclastogenesis. RESULTS: Myeloid cells treated with CM from Ocy-GsαKO showed a significant increase in cell proliferation compared to Ocy-GsαCtrl CM and non-treated control. BMNCs treated with CM from Ocy-GsαCtrl and Ocy-GsαKO showed a significant increase in cell proliferation as compared to non-treated control. Osteoclast differentiation was significantly suppressed by CM from Ocy-GsαCtrl and further suppressed by CM from Ocy-GsαKO compared to non-treated control. Osteoclasts exposed to CM from Ocy-GsαKO showed a significant defect in activity and function as compared to cells exposed to CM from Ocy-GsαCtrl and non-treated cells. Osteoclast apoptosis was significantly enhanced by Ocy-GsαCtrl and Ocy-GsαKO CM compared to non-treated control. Among osteocyte secreted factors, we identified neuropilin-1 (NRP-1) as a Gsα-dependent osteocytic factor capable of suppressing osteoclastogenesis. CM from Ocy-GsαKO in which M-CSF was reduced by shRNA demonstrated decrease in BMNCs proliferation, demonstrating that osteocytes are also important sources of this cytokine. CONCLUSIONS: Osteocytes produce several Gsα-dependent and -independent secreted factors capable of supporting myelopoiesis, promoting macrophage proliferation and suppressing osteoclast formation. We identified osteocyte-derived NRP-1 as a novel factor capable of decreasing osteoclastogenesis. In addition, we found that M-CSF secreted by osteocytes is responsible in part for BMNC proliferation. Future studies should focus on determining the role of osteocyte-mediated NRP-1 and other secreted factor(s) in control of myelopoiesis and osteoclastogenesis. / 2020-06-26T00:00:00Z

Hypereosinophilic (HES) syndrome is an umbrella term encompassing several disease subsets that affects humans and veterinary species, ultimately resulting in >1,500 eosinophils/uL circulating in the blood documented over six-months. This eventually culminates in end-organ infiltration and increased patient morbidity and mortality. In mice where the gene Map3k14 encoding NF -kB inducing kinase (NIK) is knocked out, a HES-like syndrome develops that is dependent on Th2 cells and cytokines. NIK is the upstream regulator of the noncanonical NF-kB pathway and is involved in lymphoid organ development, B cell lymphopoiesis, and myelopoiesis. In addition to regulating the noncanonical NF-kB pathway, NIK is also involved in regulation of kB dimers of the canonical NF-kB pathway and can function independent of NF-kB signaling by regulating lipid and glucose metabolism, mitochondrial, and RIP1 binding to influence cell survival and death. Despite previous studies performed in the Nik-/- model, the mechanisms underlying eosinophil development, plasticity, and fitness in conjunction with the bone marrow and splenic microenvironments have not been fully elucidated. In the present work, we reviewed current data exploring the influence of the noncanonical NF-kB pathway and NIK specifically on the development of acute myeloid leukemias (AMLs) and Myelodysplastic Syndrome (MDS) with a focus on how these mechanisms might induce subvariants of HES. We next examined the effect of NIK loss on eosinophilopoiesis within hematopoietic tissues in vivo and in various cell culture environments in vitro via cytology, histology, flow cytometry, FACS, positive cell selection, MTT assay, BrDU assay, and protein microarray analysis. Overall, our findings suggest that NIK influences eosinophil maturation, proliferation, metabolism, survival, and potentially plasticity in vivo and in vitro under different environmental conditions and Th2 cytokine influence. NIK loss was also associated with altered free and bound TNFR1 levels on day 13 in vitro. TNFR1 acts upstream of RIP1 and suggests that these differences may be due to NF-kB independent functions of NIK. Overall, these results provide further insight into the potential mechanisms underlying eosinophilopoiesis in the Nik-/- murine model. This information may prove useful in discovering new treatment options underlying subvariants of HES in both human and veterinary patients. / Doctor of Philosophy / A less well-known albeit important white blood cell (WBC) is the eosinophil. It is essential for combating parasitic infections but is also involved in allergic responses. Hypereosinophilic Syndrome (HES) is an umbrella term encompassing a variety of diseases that affects human and veterinary patients. It results in an overproduction of eosinophils not associated with parasitic infections or allergic responses. Although several variants of the disease exist, diagnosing subsets of HES poses a diagnostic challenge and can impact patient care and prognosis long term. Mice carrying a genetic deletion (Map3k14) encoding a kinase known as NF-kB inducing kinase (NIK) develop HES-like syndrome; these mice are hereafter referred to as Nik-/- mice. HES-like syndrome in Nik-/- mice develops secondary to NIK loss in Th2 lymphocytes (another type of WBC). NIK is an upstream regulator of the noncanonical NF-kB pathway that influences WBC, lymph node, and spleen development. NIK also regulates canonical NF-kB molecules and can function independent of NF-kB signaling by impacting fat and glucose metabolism, binding to mitochondria, and interacting with a kinase known as RIP1 to regulate cell death or survival. Despite previous work studying HES-like syndrome in Nik-/- mice, the specifics of the bone marrow and eosinophil development in response to Th2 cells have not been fully characterized. In the present work, we reviewed data exploring the noncanonical NF-kB pathway and NIK specifically in the development of WBC cancers and how this might manifest as HES. We then studied eosinophil development in the bone marrow, spleen and in culture for both Nik-/- and wild-type mice by assessing cell and tissue morphology, cell surface marker expression, response to Th2 signaling molecules, as well as cell maturation, death, metabolism, proliferation, and cytokine production. Our findings suggest that NIK is essential for eosinophil growth and survival. We also noted differences in a molecule known as TNFR1 in Nik-/- cultures on day 13. This molecule acts upstream of RIP1, suggesting an NF-kB independent function of NIK in regulating eosinophil maturation in response to Th2 molecules. This information may prove useful in discovering new treatments for HES in human and veterinary patients.

L’infection par le virus de la grippe, ou le Myxovirus influenzae de type A (IAV), constitue l'une des causes les plus importantes de maladies des voies respiratoires dans le monde. Elle conduit également à des épidémies récurrentes avec des taux élevés de morbidité et de mortalité. Des surinfections bactériennes, principalement causées par Streptococcus pneumoniae (pneumonie), sont souvent associées à la grippe et contribuent de manière significative à l’excès de mortalité. La perturbation de l'intégrité des tissus pulmonaires et la diminution de l'immunité antibactérienne au cours de l'infection par IAV sont à l’origine de la colonisation et à la dissémination des bactéries.L'infection grippale entraîne une altération profonde du compartiment de cellules myéloïdes pulmonaires caractérisée par une altération numérique ou fonctionnelle des cellules sentinelles - les macrophages alvéolaires et les cellules dendritiques conventionnelles (cDC) - et par un recrutement de cellules myéloïdes inflammatoires -les neutrophiles, les monocytes inflammatoires ou encore les cellules dendritiques inflammatoires.Les cellules myéloïdes sont originaires de la moelle osseuse (MO). Lors d’infections, la myélopoïèse peut être profondément affectée afin de maintenir la production et la mobilisation de cellules myéloïdes inflammatoires au niveau du site d’infection. A l’heure actuelle, les conséquences de l’infection grippale sur la myélopoïèse restent encore mal connues.Dans notre projet, nous rapportons que l'infection grippale conduit à une diminution transitoire du nombre de cDC (cDC1 et cDC2) dans les poumons qui coïncide avec une chute dans la MO, du nombre de progéniteurs/précurseurs impliqués dans la génération des cDC (CDP, pre-cDC et plus particulièrement les pre-cDC1). Cette diminution de la "DCpoïèse" est associée à une accélération de la génération des monocytes, i.e. monopoïèse. La différenciation altérée des cDC est indépendante des cytokines pro-inflammatoires et n'est pas due à un dysfonctionnement intrinsèque des précurseurs de cDC. De façon intéressante, nous rapportons que ces altérations au niveau de la MO sont associées à une diminution de la production de Flt3-L ou Fms-like tyrosine kinase 3 ligand, un facteur crucial pour la différenciation des DC. La supplémentation en Flt3-L au cours de la grippe rétablit la différenciation des progéniteurs de cDC dans la MO et restaure le compartiment des cDC pulmonaires. De façon intéressante, cette restauration s’accompagne d’une protection partielle contre l’infection pneumococcique secondaire caractérisée par une réduction de la charge bactérienne, une amélioration de la pathologie pulmonaire et une survie prolongée. / Influenza type A virus (IAV) infection, is one of the most important causes of respiratory diseases worldwide. It also leads to recurrent epidemics with high rates of morbidity and mortality. Secondary bacterial infections, mainly caused by Streptococcus pneumoniae (pneumonia), are often associated with influenza and contribute significantly to excess mortality. Disruption of lung tissue integrity and impaired antibacterial immunity during IAV infection participate in bacterial pulmonary colonization and dissemination out of the lungs.Influenza infection leads to a profound alteration in the pulmonary myeloid cell compartment characterized by numeric or functional alteration of sentinel cells (alveolar macrophages and conventional dendritic cells (cDC)) and recruitment of inflammatory myeloid cells (neutrophils, inflammatory monocytes and inflammatory dendritic cells).Myeloid cells originate from the bone marrow (BM). During infections, myelopoiesis may be profoundly affected in order to maintain the production and mobilization of inflammatory myeloid cells to the site of infection. At present, the consequences of influenza infection on myelopoiesis remain poorly understood.In our project, we report that influenza infection leads to a transient decrease in the number of Cdc (cDC1 and cDC2) in the lungs, and severely impairs the number of BM progenitors committed to the DC lineage (CDP, pre-cDC and, most importantly, the cDC1-biased pre-DC lineage). This reduction was associated with an increase in the production of monocytes in the BM (monopoiesis). The altered cDC differentiation was independent of pro-inflammatory cytokines and was not due to an intrinsic dysfunction of cDC precursors. Defective DC genesis during influenza was associated with a decrease in the production of the key cDC differentiation factor, Fms-like tyrosine kinase 3 ligand (Flt3-L). Importantly, Flt3-L overexpression during influenza restores the differentiation of BM progenitors into cDC - a phenomenon associated with repopulation of cDC in the lungs. The restoration of pulmonary cDC associates with a partial protection against secondary pneumococcal infection characterized by reduced bacterial loads, improved pathological outcomes and prolonged survival.

No description available.

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / O gênero Pterodon pertence à família das Papilonaceas e inclui cinco espécies nativas do Brasil: P. pubescens Benth., P. emarginatus Vog., P. apparicioi Pedersoli e P. abruptus Benth., sendo a espécie objeto deste estudo a P. polygalaeflorus Benth.. Seus frutos são livremente comercializados em mercados da flora medicinal e utilizados pela medicina popular devido a propriedades anti-reumática, analgésica, antiinflamatória, dentre outros efeitos associados a esses frutos. O principal uso popular está relacionado ao efeito antiartrítico que parece se encontrar na fração oleosa do fruto. O objetivo deste trabalho foi avaliar o extrato etanólico de Pterodon polygalaeflorus (EEPpg) quanto ao seu potencial antiinflamatório crônico através do modelo de artrite induzida por colágeno (CIA) e seu efeito sobre os linfócitos in vitro, bem como sobre a expansão de células MAC-1+ induzida por adjuvante completo de Freund (AFC). A caracterização química do EEPpg foi realizada por cromatografia em camada delgada (TLC), cromatografia líquida de alta performance (HPLC) e cromatografia gasosa acoplada a espectrômetro de massa (GC-MS), através dos quais uma gama de compostos, incluindo terpenóides de polaridades variadas e flavonóides, foram observados. No modelo de CIA, o EEPpg reduziu significativamente parâmetros associados ao desenvolvimento e progressão da doença e à severidade da doença , inibindo em até 99% o seu desenvolvimento e levando a ausência de sinais clínicos evidentes após tratamento com as menores doses do extrato (0,01 mg/kg e 0,001 mg/kg). O tratamento com EEPpg também reduziu características histopatológicas típicas de articulações de animais com CIA, que também são observadas na artrite reumatóide. O EEPpg reduziu significativamente o peso dos linfonodos dos camundongos, bem como o número absoluto de segmentados, monócitos e linfócitos no sangue. In vitro, O EEPpg mostrou uma atividade anti-proliferativa dos esplenócitos estimulados com concanavalina A (Con A) ou lipopolissacarídeo (LPS) analisada através do ensaio de redução do sal de tetrazólio MTT, corroborada pelo seu efeito sobre o ciclo celular de linfócitos estimulados com Con A, onde o EEPpg nas concentrações de 5, 10 e 20 μg/mL reduziu significativamente, de maneira concentração-dependente, o número de células nas fases S+G2/M e aumentou na fase G0/G1 do ciclo celular. O efeito anti-proliferativo do EEPpg parece também estar associado ao aumento da apoptose dos linfócitos após estimulação com Con A, com aumento estatisticamente significativo no percentual de células mortas por apoptose nas maiores concentrações . O EEPpg inibiu a expansão de células Mac-1+ induzida por AFC no baço, porém não no peritônio. Esse resultado sugere um efeito inibidor do EEPpg sobre a migração celular para as articulações artríticas. Esses resultados contribuem para a validação do uso popular de P. polygalaeflorus contra doenças relacionadas a processos inflamatórios e imunes, sobretudo na artrite reumatóide, antes nunca demonstrado. / The genus Pterodon belongs to the family Papilonaceas and includes five native species of Brazil: P. pubescens Benth., P. emarginatus Vog., P. apparicioi Pedersoli and P. abruptus Benth., being the object of this study the species P. polygalaeflorus Benth . Its fruits are freely traded in markets and medicinal plants used in folk medicine due to anti-rheumatic, analgesic, antiinflammatory, among other effects associated with these fruits. The main use is related to the popular anti-arthritic effect that seems to be found in oily fraction of the fruit. The aim of this study was to evaluate the ethanol extract of Pterodon polygalaeflorus (EEPpg) for their potential anti-inflammatory chronic through the model of collagen-induced arthritis (CIA) and its effect on lymphocytes in vitro, as well as the MAC-cell expansion 1 + induced by Freund's complete adjuvant (CFA). The chemical characterization of EEPpg was performed by thin layer chromatography (TLC), high-performance liquid chromatography (HPLC) and gas chromatography coupled with mass spectrometry (GC-MS), through which a range of compounds, including terpenoids polarity varied and flavonoids, were observed. In model of CIA, EEPpg significantly reduced parameters associated with the development and progression of disease and disease severity, inhibiting up to 99% its development and leading to the absence of obvious clinical signs after treatment with lower doses of the extract (0,01 mg/kg and 0.001 mg/kg). Treatment with EEPpg also reduced histopathological features typical of arthritic joints that are also observed in rheumatoid arthritis. The EEPpg significantly reduced the weight of the lymph nodes of mice as well as the absolute number of segmented, monocytes and lymphocytes in the blood. In vitro, EEPpg showed an anti-proliferative activity of splenocytes stimulated with concanavalin A (Con A) or lipopolysaccharide (LPS) analyzed by testing to reduce the tetrazolium salt MTT, supported by its effect on the cell cycle of lymphocytes stimulated with Con A, where the EEPpg at concentrations of 5, 10 and 20 mg/mL significantly reduced in concentration-dependent manner, the number of cells in phases S + G2 / M and increased G0/G1 phase of cell cycle. The anti-proliferative EEPpg seems also to be associated with increased apoptosis of lymphocytes after stimulation with Con A, with a statistically significant increase in the percentage of dead cells by apoptosis at higher concentrations. The EEPpg inhibited the expansion of Mac-1 + cells induced by AFC in the spleen but not in the peritoneum. This suggests an inhibitory effect on cell migration by EEPpg into arthritic joints. These results help to validate the popular use of P. polygalaeflorus against diseases related to inflammatory and immune disorders, especially rheumatoid arthritis, never shown before.