title: CD16-positive circulating monocytes and fibrotic manifestations of systemic sclerosis.
abstract: The objective of this study is to assess the association of clinical manifestations of systemic sclerosis (SSc) with the absolute count of circulating blood monocyte subpopulations according to their membrane expression of CD16. Forty-eight consecutive patients fulfilling the 2013 ACR/EULAR classification criteria for SSc were included in this cross-sectional study. CD16+ monocyte absolute count was defined by flow cytometry and confronted to the clinical characteristics of SSc patients. Twenty-three healthy donors (HD) were randomly selected for comparison. SSc patients had an increased number of total circulating blood monocytes compared to HD (p < 0.001). The CD16- subpopulation absolute count was increased in SSc patients compared to HD (p < 0.001) but was similar in limited SSc (lSSc) and diffuse SSc (dSSc). On the contrary, the CD16+ population absolute count was increased in dSSc compared to both HD and lSSc patients (dSSc 0.071 Giga/L (±0.034) vs HD 0.039 Giga/L (±0.030), p < 0.01, and dSSc 0.071 Giga/L (±0.034) vs lSSc 0.048 Giga/L (±0.024), p < 0.05). The CD16+ monocyte subpopulation absolute count was significantly correlated with the severity of skin fibrosis evaluated by the modified Rodnan skin score (p < 0.001). The CD16+ monocyte subpopulation was also associated with pulmonary fibrosis (p < 0.05), with the severity of the restrictive ventilatory defect evaluated by total lung capacity (p < 0.05) and with the pulmonary function impairment reflected by diffusing capacity of the lungs for carbon monoxyde measures (p < 0.01). These results suggest that CD16+ monocytes are associated with the main fibrotic manifestations of SSc and their role in the pathogenesis of fibrosis in this autoimmune disorder should therefore be further considered.
authors.affiliation: INSERM, U1085, Research Institute in Health, Environment and Occupation/Institut de Recherche en Santé, Environnement et Travail (IRSET), University of Rennes 1, Rennes, France. Alain.lescoat@chu-rennes.fr.|Department of Internal Medicine, CHU Rennes, South Hospital, 16 bd de Bulgarie - BP 90347, 35203, Rennes Cedex 2, France. Alain.lescoat@chu-rennes.fr.
authors.forename: Alain
authors.identifier: http://orcid.org/0000-0003-2081-8558
authors.initials: A
authors.lastname: Lescoat
authors.affiliation: INSERM, U1085, Research Institute in Health, Environment and Occupation/Institut de Recherche en Santé, Environnement et Travail (IRSET), University of Rennes 1, Rennes, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Lecureur
authors.affiliation: CHU Rennes, Laboratoire d'Hématologie, Pôle de Biologie, 35033, Rennes, France.|INSERM, U917, University of Rennes 1, Rennes, France.
authors.forename: Mikael
authors.initials: M
authors.lastname: Roussel
authors.affiliation: CHU Rennes, Laboratoire d'Hématologie, Pôle de Biologie, 35033, Rennes, France.
authors.forename: Béatrice Ly
authors.initials: BL
authors.lastname: Sunnaram
authors.affiliation: Department of Internal Medicine, CHU Rennes, South Hospital, 16 bd de Bulgarie - BP 90347, 35203, Rennes Cedex 2, France.
authors.forename: Alice
authors.initials: A
authors.lastname: Ballerie
authors.affiliation: Department of Rheumatology, CHU Rennes, University of Rennes 1, Rennes, France.|INSERM U991, University of Rennes 1, Rennes, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Coiffier
authors.affiliation: INSERM, U1085, Research Institute in Health, Environment and Occupation/Institut de Recherche en Santé, Environnement et Travail (IRSET), University of Rennes 1, Rennes, France.|Department of Respiratory Diseases, CHU Rennes, University of Rennes 1, Rennes, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Jouneau
authors.affiliation: INSERM, U1085, Research Institute in Health, Environment and Occupation/Institut de Recherche en Santé, Environnement et Travail (IRSET), University of Rennes 1, Rennes, France.|CHU Rennes, Laboratoire d'Hématologie, Pôle de Biologie, 35033, Rennes, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Fardel
authors.affiliation: CHU Rennes, Laboratoire d'Hématologie, Pôle de Biologie, 35033, Rennes, France.|INSERM, U917, University of Rennes 1, Rennes, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Fest
authors.affiliation: INSERM, U1085, Research Institute in Health, Environment and Occupation/Institut de Recherche en Santé, Environnement et Travail (IRSET), University of Rennes 1, Rennes, France.|Department of Internal Medicine, CHU Rennes, South Hospital, 16 bd de Bulgarie - BP 90347, 35203, Rennes Cedex 2, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Jégo
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005355:Fibrosis / Q000097:blood / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism* / Q000473:pathology; D017452:Receptors, IgG / Q000378:metabolism*; D012595:Scleroderma, Systemic / Q000097:blood* / Q000473:pathology; D012720:Severity of Illness Index; D012867:Skin / Q000473:pathology
chemical_list: D017452:Receptors, IgG
keywords: CD16; Interstitial lung disease; Monocytes; Pulmonary arterial hypertension; Systemic sclerosis