CD81 and CD48 show different expression on blood eosinophils in systemic sclerosis: new markers for disease and pulmonary inflammation?

Abstract

Objective: In systemic sclerosis (SSc) related interstitial lung disease, elevated eosinophil counts in bronchoalveolar lavage are associated with worse outcome. We hypothesize that eosinophils are activated in the peripheral circulation, thereby increasing their recruitment to affected tissues and contributing to inflammation and fibrosis. The aim of this study was to characterize the blood eosinophils in SSc patients. Methods:Expressions of surface markers CD11b, CD44, CD48, CD54, CD69, CD81 and HLA-DR on CD16 low CD9 high expressing eosinophils were measured by flow cytometry in whole blood from SSc patients (n = 32) and controls (n = 11).Results: Expression of CD54, CD69 and HLA-DR were undetectable in all groups. CD44and CD11b expression levels were similar between groups. CD81 expression was lower in patients compared to controls independent of disease duration (p = 0.001). CD48 expression was increased in patients with a short disease duration (< 2 years) compared to both controls (p = 0.042) and patients with longer disease duration (p = 0.027). In patients with short disease duration, increased CD48 expression was associated with alveolar inflammation as measured by an increased concentration of alveolar nitric oxide (r = 0.76, p = 0.003). Conclusion:Blood eosinophils change phenotype during disease evolution in SSc, and CD48 expression may be used as a biomarker for pulmonary inflammation.

Decreased salivary concentration of CD9 and CD81 exosome‐related tetraspanins may be associated with the periodontal clinical status

“…The foremost findings reported here were that the median levels of CD9 and CD81 exosomes are significantly decreased in the periodontitis patients in comparison with periodontally healthy controls, so that an altered exosome‐signalling pathway may constitute an important mechanism for periodontal pathogenesis. In agreement with the present findings, previous data have shown a potential pathogenic role for dysregulation of these proteins in both systemic inflammation (Suzuki et al., ; Takeda et al., , ; Wuttge et al., ) and delayed wound healing (Jiang et al., ; Zhang et al., ), suggesting a preventive role of tetraspanins CD9 and CD81 in senescence and inflammation (Jin et al., ; Takeda et al., ).…”

Evaluation of Soluble CD48 Levels in Patients with Allergic and Nonallergic Asthma in Relation to Markers of Type 2 and Non-Type 2 Immunity: An Observational Study

“…CD48 has numerous roles in the regulation of immunity and has been shown to be elevated in patients with hematopoietic malignancy, infections, and inflammatory diseases with autoimmunity [ 1 , 2 , 4 , 6 , 12 ]. Recently, CD48 was shown to be associated with pulmonary inflammation in patients with systemic sclerosis [ 15 ]. Furthermore, previous studies have shown that neutralization of CD48 significantly reduced proinflammatory cytokine expression [ 8 ] thus elevated sCD48 levels in patients with nonallergic asthma may presumably be related to an increased inflammatory state.…”

“…We have shown that CD48 participates in allergic eosinophilic airway inflammation and is a potential target for the suppression of asthma in mice, but it has also been shown that CD48 participates in nonallergic respiratory inflammatory processes [ 4 , 8 , 13 – 15 ]. We have recently found that mCD48 and sCD48 are expressed differentially in asthmatic patients of varying disease severity, sCD48 being significantly elevated in patients with mild asthma as compared to control.…”

Elevated Serum Level of CD48 in Patients with Intermittent Allergic Rhinitis

“…The role of CD48 as a costimulatory receptor of various immune responses is still being studied. The previous papers concentrated mainly on autoimmune diseases such as systemic sclerosis [18] or systemic lupus erythematosus [19], cancer (multiple myeloma [19] and acute myeloid leukemia [20]), and bacterial and other infectious diseases [21]. Interactions between CD48 and CD244 (2B4) on mast cells, eosinophils, and basophils suggest that these cell types can act synergistically in the “allergic effector unit” to promote inflammation.…”