Macrophage phenotype in the epigallocatechin-3-gallate (EGCG)-modified collagen determines foreign body reaction
JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE
Authors: Chu, Chenyu; Liu, Li; Wang, Yufei; Wei, Shimin; Wang, Yuanjing; Man, Yi; Qu, Yili
Abstract
Collagen has been widely used in guided bone regeneration, and the implantation of collagen membranes will elicit the foreign body reaction (FBR). The imbalance of FBR often leads to failure of dental implants. Therefore, modulation of the FBR after implantation of collagen membranes becomes increasingly important. Macrophages, pivotal in FBR, have been distinguished into pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes. Epigallocatechin-3-gallate (EGCG)-modified collagen membranes have been previously shown to regulate secretion of inflammatory factors. In this study, immunohistochemistry of CD31 showed that areas of blood vessels were significantly enlarged after implantation of EGCG-modified collagen membranes compared with those treated with pure collagen membranes. Besides, haematoxylin-eosin staining and immunofluorescence showed an increased number of M2 macrophages after implantation of EGCG-modified collagen membranes. In addition, quantitative real-time polymerase chain reaction showed that after implantation of EGCG-modified collagen membranes, expression of CXCL1 (predominant chemoattractants to neutrophils and inflammation promotors) was significantly downregulated, whereas expressions of STAB1, CCR2, CCR3, CCL2, and CCL3 (related to M2 macrophages) were significantly upregulated. From these findings, we conclude that EGCG-modified collagen membranes were able to regulate the recruitment and polarization of macrophages, so that ameliorate FBR.
A regulatory dendritic cell signature correlates with the clinical efficacy of allergen-specific sublingual immunotherapy
JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY
Authors: Zimmer, Aline; Bouley, Julien; Le Mignon, Maxime; Pliquet, Elodie; Horiot, Stephane; Turfkruyer, Mathilde; Baron-Bodo, Veronique; Horak, Friedrich; Nony, Emmanuel; Louise, Anne; Moussu, Helene; Mascarell, Laurent; Moingeon, Philippe
Abstract
Background: Given their pivotal role in the polarization of T-cell responses, molecular changes at the level of dendritic cells (DCs) could represent an early signature indicative of the subsequent orientation of adaptive immune responses during immunotherapy. Objective: We sought to investigate whether markers of effector and regulatory DCs are affected during allergen immunotherapy in relationship with clinical benefit. Methods: Differential gel electrophoresis and label-free mass spectrometry approaches were used to compare whole proteomes from human monocyte-derived DCs differentiated toward either regulatory or effector functions. The expression of those markers was assessed by using quantitative PCR in PBMCs from 79 patients with grass pollen allergy enrolled in a double-blind, placebo-controlled clinical study evaluating the efficacy of sublingual tablets in an allergen exposure chamber over a 4-month period. Results: We identified several markers associated with DC1 and/or DC17 effector DCs, including CD71, FSCN1, IRF4, NMES1, MX1, TRAF1. A substantial phenotypic heterogeneity was observed among various types of tolerogenic DCs, with ANXA1, Complement component 1 (C1Q), CATC, GILZ, F13A, FKBP5, Stabilin-1 (STAB1), and TPP1 molecules established as shared or restricted regulatory DC markers. The expression of 2 of those DCs markers, C1Q and STAB1, was increased in PBMCs from clinical responders in contrast to that seen in nonresponders or placebo-treated patients. Conclusion: C1Q and STAB1 represent candidate biomarkers of early efficacy of allergen immunotherapy as the hallmark of a regulatory innate immune response predictive of clinical tolerance. (J Allergy Clin Immunol 2012;129:1020-30.)