Frequency of Th17 CD4+ T cells in early rheumatoid arthritis: A marker of anti-CCP seropositivity

Objective: To examine the frequency and phenotype of Th17 cells in the peripheral blood of early RA (eRA) patients. Methods: CD4+ T cells were isolated from the peripheral blood of 33 eRA patients, 20 established RA patients and 53 healthy controls (HC), and from the synovial fluid of 20 established RA patients (RASF), by ficoll-hypaque gradient and magnetical negative selection. After polyclonal stimulation, the frequency of Th17 and Th1 cells was determined by flow cytometry and concentrations of IL-17, IFN-γ, TNF-α and IL-10 were measured by ELISA in cell-free supernatants. Results: When all of our eRA patients were analyzed together, a significantly lower percentage of circulating Th17 cells and a lower CD4-derived IL-17 secretion were observed in comparison with HC. However, after stratifying by anti-CCP antibody status, circulating Th17 cells were decreased in anti-CCP(+) but not in anti-CCP(-)-eRA. All Th17 cells were CD45RO+CD45RA- and CCR6+. Dual Th17/Th1 cells were also exclusively decreased in anti-CCP(+)-eRA. Circulating Th17 and Th17/Th1 cells were negatively correlated with anti-CCP titres. When anti-CCP(+)-eRA patients were retested one year after initiating treatment with oral methotrexate, their circulating Th17 frequency was no longer different from HC. Of note, the percentage of circulating Th1 cells and the secretion of CD4-derived IFN-γ, TNF-α and IL-10 were not different between eRA patients and HC. In established RA patients, circulating Th17 and T17/Th1 cell frequencies were comparable to HC. In RASF, both Th17 and Th1 cells were increased when compared with blood of eRA patients, established RA patients and HC. Conclusion: Decreased circulating Th17 levels in eRA seem to be a marker of anti-CCP seropositivity, and return to levels observed in healthy controls after treatment with methotrexateThis work was supported by Ministerio de Ciencia e Innovación grant SAF 2009-07100, (http://www.idi.mineco.gob.es/portal/site/MICINN) and by RETICS Program, RD08/0075 (RIER) from ‘‘Instituto de Salud Carlos III’’ (ISCIII) (http://www.isciii.es/

AT514, a cyclic depsipeptide from Serratia marcescens, induces apoptosis of B-chronic lymphocytic leukemia cells. Interference with the Akt/NF-kB survival pathway

8 páginas, 5 figuras -- PAGS nros. 572-579Clinical treatment of B-cell chronic lymphocytic leukemia (B-CLL) is limited by the progressive drug resistance and nonselectivity of most drugs towards malignant cells. Depsipeptides are present in certain bacteria and display potent antitumor activity. We have studied the effect of the novel cyclodepsipeptide AT514 (serratamolide) from Serratia marcescens on B-CLL cell viability. AT514 induced apoptosis of B-CLL cells from the 21 patients studied, as confirmed by Annexin-V binding and nuclei condensation, with an average IC50 of 13 M. AT514 was effective in those B-CLL cases resistant to fludarabine, but had no effect on normal PBL. AT514 preferentially activated the intrinsic apoptotic pathway, as evidenced by loss of mitochondrial membrane potential, release of cytochrome c and activation of caspase-9 and -3, but not of caspase-8. Importantly, AT514 interfered with phosphatidylinositol-3 kinase and protein kinase C survival signals since it increased the apoptotic effect of LY294002 and BisI inhibitors, and induced Akt dephosphorylation at Ser 473. AT514 also decreased NF-B activity by dramatically reducing the levels of p65 in B-CLL. This was confirmed on functional assays using NF-B-luc-transfected Raji cells and transgenic mice. Our results establish that AT514 induces apoptosis of primary B-CLL cells and could be useful for clinical treatment of this malignancyThis work was supported by grants 08.3/0030.1/2003 from the Comunidad Autónoma de Madrid, SAF2003-00824 from the Ministerio de Ciencia y Tecnología (MCyT), and 01/1183 from Fondo de Investigación Sanitaria (to AGP); and CIDEM Grant 301888 (Generalitat de Catalunya)/Fundació Bosch i Gimpera, to RPT). E Escobar and E López-Martín were supported by fellowships from MCyTPeer reviewe

RUNX/AML and C/EBP factors regulate CD11a integrin expression in myeloid cells through overlapping regulatory elements

The CD11a/CD18 (leukocyte functionassociated antigen 1 [LFA-1]) integrin mediates critical leukocyte adhesive interactions during immune and inflammatory responses. The CD11a promoter directs CD11a/CD18 integrin expression, and its activity in lymphoid cells depends on a functional RUNX1/AML-1–binding site (AML-110) within the MS7 sequence. We now report that MS7 contains a C/EBPbinding site (C/EBP-100), which overlaps with AML-110 and is bound by C/EBP factors in myeloid cells. C/EBP and RUNX/ AML factors compete for binding to their respective cognate elements and bind to the CD11a promoter MS7 sequence in a cell lineage- and differentiation-dependent manner. In myeloid cells MS7 is primarily recognized by C/EBP factors in proliferating cells whereas RUNX/AMLfactors (especially RUNX3/AML-2) bind to MS7 in differentiated cells. RUNX3/AML-2 binding to the CD11a promoter correlates with increased RUNX3/AML-2 protein levels and enhanced CD11a/CD18 cell surface expression. The relevance of the AML-110 element is underscored by the ability of AML-1/ETO to inhibit CD11a promoter activity, thus explaining the low CD11a/CD18 expression in t(8;21)–containing myeloid leukemia cells. Therefore, the expression of the CD11a/CD18 integrin in myeloid cells is determined through the differential occupancy of the CD11a proximal promoter by transcription factors implicated in the pathogenesis of myeloid leukemia

Signal integration and transcriptional regulation of the inflammatory response mediated by the GM-/MCSF signaling axis in human monocytes

In recent years, the macrophage colony-stimulating factor (M-CSF) and granulocyte-macrophage CSF (GM-CSF) cytokines have been identified as opposing regulators of the inflammatory program. However, the two cytokines are simultaneously present in the inflammatory milieu, and it is not clear how cells integrate these signals. In order to understand the regulatory networks associated with the GM/M-CSF signaling axis, we analyzed DNA methylation in human monocytes. Our results indicate that GM-CSF induces activation of the inflammatory program and extensive DNA methylation changes, while M-CSF-polarized cells are in a less differentiated state. This inflammatory program is mediated via JAK2 associated with the GM-CSF receptor and the downstream extracellular signal-regulated (ERK) signaling. However, PI3K signaling is associated with a negative regulatory loop of the inflammatory program and M-CSF autocrine signaling in GM-CSF-polarized monocytes. Our findings describe the regulatory networks associated with the GM/M-CSF signaling axis and how they contribute to the establishment of the inflammatory program associated with monocyte activation.This work was supported by grants from the Plan Nacional de I+D+I 2013– 2016 ISCIII (Institute of Health Carlos III; PI16/01318, PI17/01244, PI17/ 0119, PI16/1900, and PI19/00184); the Gobierno del Principado de Asturias; the PCTI-Plan de Ciencia, Tecnologı´a e Innovacio´ n 2013-2017 (grant IDI/ 2018/144); FEDER ‘‘Funding Program of the European Union’’; the Red Española de Investigación Renal (REDinREN) (RD16/0009/0020, RD016/0009/002, and RD016/0009/001); the Agencia Estatal de Investigación (AEI) (ayuda Juan de la Cierva-Incorporaciόn; IJCI-2017-33347 to R.M.R.); and the Instituto de Salud Carlos III (Contratos Sara Borrell; CD16/00033 to C.H.). CIC bioGUNE support was provided by the Basque Department of Industry, Tourism and Trade (Etortek and Elkartek programs), the Innovation Technology Department of Bizkaia County, the CIBERehd Network, and Spanish MINECO, the Severo Ochoa Excellence Accreditation (SEV-2016-0644

Activation of LXR nuclear receptors impairs the anti-inflammatory gene and functional profile of M-CSF-dependent human monocyte-derived macrophages

13 p.-7 fig.Liver X Receptors (LXR) control cholesterol metabolism and exert anti-inflammatory actions but their contribution to human macrophage polarization remains unclear. The LXR pathway is enriched in pro-inflammatory macrophages from rheumatoid arthritis as well as in tumors-associated macrophages from human tumors. We now report that LXR activation inhibits the anti-inflammatory gene and functional profile of M-CSF-dependent human macrophages, and prompts the acquisition of a pro-inflammatory gene signature, with both effects being blocked by an LXR inverse agonist. Mechanistically, the LXR-stimulated macrophage polarization shift correlates with diminished expression of MAFB and MAF, which govern the macrophage anti-inflammatory profile, and with enhanced release of activin A. Indeed, LXR activation impaired macrophage polarization in response to tumor-derived ascitic fluids, as well as the expression of MAF- and MAFB-dependent genes. Our results demonstrate that LXR activation limits the anti-inflammatory human macrophage polarization and prompts the acquisition of an inflammatory transcriptional and functional profile.This work was supported by grants from Ministerio de Ciencia, Investigación y Universidades (SAF2017-83785-R to MV and ALC), Ministerio de Ciencia, Innovación y Universidades y Fondo Europeo de Desarrollo Regional (FEDER) (SAF2017-90604-REDT and PID2019-104284RB-I00/AEI/10.13039/501100011033 to AC), Fundación La Marató/TV3 (Grant 201619.31 to ALC), Instituto de Salud Carlos III (Grant PI20/00316 to AP-K), and Red de Investigación en Enfermedades Reumáticas (RIER, RD16/0012/0007) from Instituto de Salud Carlos III and cofinanced by the European Regional Development Fund “A way to achieve Europe” (ERDF) to AP-K and ALC. This work was also supported in part by a grant from the Dutch Society for Clinical Chemistry (NVKC) to IM and R. de Jonge. AGA was funded by FPU predoctoral fellowship (FPU16/02756) from Ministerio de Universidades.Peer reviewe

CCL20/TNF/VEGFA Cytokine Secretory Phenotype of Tumor-Associated Macrophages Is a Negative Prognostic Factor in Cutaneous Melanoma

TAMs constitute a large fraction of infiltrating immune cells in melanoma tissues, but their significance for clinical outcomes remains unclear. We explored diverse TAM parameters in clinically relevant primary cutaneous melanoma samples, including density, location, size, and polarization marker expression; in addition, because cytokine production is a hallmark of macrophages function, we measured CCL20, TNF, and VEGFA intracellular cytokines by single-cell multiparametric confocal microscopy. The Kaplan–Meier method was used to analyze correlation with melanoma-specific disease-free survival and overall survival. No significant correlations with clinical parameters were observed for TAM density, morphology, or location. Significantly, higher contents of the intracellular cytokines CCL20, TNF, and VEGFA were quantified in TAMs infiltrating metastasizing compared to non-metastasizing skin primary melanomas (p < 0.001). To mechanistically explore cytokine up-regulation, we performed in vitro studies with melanoma-conditioned macrophages, using RNA-seq to explore involved pathways and specific inhibitors. We show that p53 and NF-κB coregulate CCL20, TNF, and VEGFA in melanoma-conditioned macrophages. These results delineate a clinically relevant pro-oncogenic cytokine profile of TAMs with prognostic significance in primary melanomas and point to the combined therapeutic targeting of NF-kB/p53 pathways to control the deviation of TAMs in melanoma