IL4 induces IL6-producing M2 macrophages associated to inhibition of neuroinflammation in vitro and in vivo

Background: Myeloid cells, such as macrophages and microglia, play a crucial role in neuroinflammation and have been recently identified as a novel therapeutic target, especially for chronic forms. The general aim would be to change the phenotype of myeloid cells from pro- to anti-inflammatory, favoring their tissue-trophic and regenerative functions. Myeloid cells, however, display a number of functional phenotypes, not immediately identifiable as pro- or anti-inflammatory, and associated to ambiguous markers. Methods: We employed in vitro assays to study macrophage polarization/differentiation in the presence of classical polarizing stimuli such as IFNγ (pro-inflammatory) and IL4 (anti-inflammatory). We induced neuroinflammation in mice by immunization with a myelin antigen and treated diseased mice with intracisternal delivery of an IL4-expressing lentiviral vector. We analyzed clinical, pathological, and immunological outcomes with a focus on myeloid cells. Results: We found that IL6, usually considered a pro-inflammatory cytokine, was released in vitro by macrophages treated with the anti-inflammatory cytokine IL4. We show the existence of macrophages expressing IL6 along with classical anti-inflammatory markers such as CD206 and demonstrate that these cells are immunosuppressive in vitro. In neuroinflamed mice, we show that IL4 delivery in the central nervous system (CNS) is associated with clinical and pathological protection from disease, associated with increased IL6 expression in infiltrating macrophages. Conclusions: IL6 is known to mediate both pro- and anti-inflammatory effects, having two distinct ways to induce cell-signaling: either through the membrane bound receptor (anti-inflammatory) or through trans-signaling (pro-inflammatory). We show here that IL6-expressing macrophages are associated to protection from neuroinflammation, suggesting that IL6 anti-inflammatory properties prevail in the CNS, and calling for a general reconsideration of IL6 in macrophage polarization

Lentiviral-mediated administration of IL-25 in the CNS induces alternative activation of microglia

n/

Usability of rectal swabs for microbiome sampling in a cohort study of hematological and oncological patients

Objectives Large-scale clinical studies investigating associations between intestinal microbiota signatures and human diseases usually rely on stool samples. However, the timing of repeated stool sample collection cannot be predefined in longitudinal settings. Rectal swabs, being straightforward to obtain, have the potential to overcome this drawback. Therefore, we assessed the usability of rectal swabs for microbiome sampling in a cohort of hematological and oncological patients. Study design We used a pipeline for intestinal microbiota analysis from deep rectal swabs which was established and validated with test samples and negative controls. Consecutively, a cohort of patients from hematology and oncology wards was established and weekly deep rectal swabs taken during their admissions and re-admissions. Results Validation of our newly developed pipeline for intestinal microbiota analysis from rectal swabs revealed consistent and reproducible results. Over a period of nine months, 418 rectal swabs were collected longitudinally from 41 patients. Adherence to the intended sampling protocol was 97%. After DNA extraction, sequencing, read pre-processing and filtering of chimeric sequences, 405 of 418 samples (96.9%) were eligible for further analyses. Follow-up samples and those taken under current antibiotic exposure showed a significant decrease in alpha diversity as compared to baseline samples. Microbial domination occurred most frequently by Enterococcaceae (99 samples, 24.4%) on family level and Enterococcus (90 samples, 22.2%) on genus level. Furthermore, we noticed a high abundance of potential skin commensals in 99 samples (24.4%). Summary Deep rectal swabs were shown to be reliable for microbiome sampling and analysis, with practical advantages related to high sampling adherence, easy timing, transport and storage. The relatively high abundance of putative skin commensals in this patient cohort may be of potential interest and should be further investigated. Generally, previous findings on alpha diversity dynamics obtained from stool samples were confirmed

Human papillomavirus, high-grade intraepithelial neoplasia and killer immunoglogulin-like receptors: a Western Australian cohort study

Background: Human papillomavirus (HPV) is the causative agent in cervical cancer and HPV genotypes 16 and 18 cause the majority of these cancers. Natural killer (NK) cells destroy virally infected and tumour cells via killer immunoglobulin-like receptors (KIR) that recognize decreased MHC class I expression. These NK cells may contribute to clearance of HPV infected and/or dysplastic cells, however since KIR controls NK cell activity, KIR gene variation may determine outcome of infection.Methods: KIR gene frequencies were compared between 147 patients with a history of high-grade cervical intraepithelial neoplasia (CIN) and a control population of 187, to determine if any KIR genes are associated with high-grade CIN. In addition a comparison was also made between cases of high grade CIN derived from 30 patients infected with HPV 16/18 and 29 patients infected with non-16/18 HPV to determine if KIR variation contributes to the disproportional carcinogenesis derived from HPV 16/18 infection.Results: High-grade CIN was weakly associated with the absence of KIR2DL2 and KIR2DS2 (p = 0.046 and 0.049 respectively, OR 0.6; 95% CI 0.4 – 0.9) but this association was lost after correction for multi-gene statistical analysis.No difference in KIR gene frequencies was found between high-grade CIN caused by HPV 16/18 and non-16/18.Conclusion: No strong association between KIR genes, high-grade CIN and HPV genotype was found in the Western Australian population

Role of zinc and α2macroglobulin on thymic endocrine activity and on peripheral immune efficiency (natural killer activity and interleukin 2) in cervical carcinoma

Decreased natural killer (NK) activity as well as interleukin 2 (IL-2) are risk factors for the progression of cervical carcinoma. NK activity and IL-2 may be thymus controlled. Plasma levels of active thymulin, a zinc-dependent thymic hormone (ZnFTS), are reduced in cancer because of the low peripheral zinc bioavailability. Zinc and thymulin are relevant for normal immune functions. α2-Macroglobulin is an inhibitor of matrix metalloproteases (MMPs) against invasive tumour proliferation. Because α2-macroglobulin has a binding affinity (Kd) for zinc that is higher than does thymulin, it may play a key role in immune efficiency in cancer. Plasma samples of 22 patients (age range 35–60 years) with locally advanced squamous cervical carcinoma and with FIGO stage Ib2–IIb were examined. They showed reduced active thymulin, decreased NK activity and IL-2 production, increased soluble IL-2 receptor (sIL-2R) and augmented α2-macroglobulin in the circulation, whereas plasma zinc levels were within the normal range for age. Significant positive correlations were found between zinc or active thymulin and α2-macroglobulin (r = 0.75, P< 0.01, r = 0.78, P< 0.01, respectively) in cancer patients. In vitro zinc increases IL-2 production from peripheral blood mononuclear cells (PBMCs) of cancer patients. These data suggest that an increase in α2-macroglobulin, which competes with thymulin for zinc binding, may be involved in causing a thymulin deficit with a consequent decrease of IL-2 and NK cytotoxicity. Thus, physiological zinc treatment in cervical carcinoma maybe restores impaired central and peripheral immune efficiency. © 1999 Cancer Research Campaig

Influence of angiogenetic factors and matrix metalloproteinases upon tumour progression in non-small-cell lung cancer

We attempted to investigate immunohistochemical expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor (PD-ECGF), c-erbB-2, matrix metalloproteinase-2 (MMP-2), and MMP-9 using surgical specimens of 119 non-small-cell lung carcinoma (NSCLC) cases and to evaluate the relationship between the expression levels of each molecule and clinicopathological factors or prognosis. VEGF expression levels were significantly associated with the local invasion (P = 0.0001), lymph node involvement (pN-factor) (P = 0.0019), pathological stage (p-stage) (P = 0.0027) and lymphatic permeation (P = 0.0389). PD-ECGF expression levels were associated with pN-factor (P = 0.0347). MMP-2 expression levels were associated with pN-factor (P = 0.004) and lymphatic permeation (P = 0.0056). Also, MMP-9 expression levels showed a significant correlation to local invasion (P = 0.0012), pN-factor (P = 0.0093) and p-stage (P = 0.0142). Multivariate analysis showed VEGF to be the most related to local invasion (P = 0.0084), and MMP-2 was the only factor with significant independent impact on lymphatic permeation (P = 0.0228). Furthermore, log-rank analysis showed significant association with poor survival by VEGF, bFGF, MMP-2 and MMP-9. Especially, combined overexpression of VEGF and MMP-2 revealed poor prognosis, our study might provide a basis for the better evaluation of biological characteristics and a new therapeutic strategy based on chemotherapy. © 2001 Cancer Research Campaign http://www.bjcancer.co