Marka A. Lyons

OBJECTIVES: To characterise the peripheral blood cell (PBC) gene expression changes ensuing from mycophenolate mofetil (MMF) or cyclophosphamide (CYC) treatment and to determine the predictive significance of baseline PBC transcript scores for response to immunosuppression in systemic sclerosis (SSc)-related interstitial lung disease (ILD). METHODS: composite modular scores for the course of forced vital capacity (FVC) per cent predicted measurements from 3 to 12 months. RESULTS: 134 patients with SSc-ILD (CYC=69 and MMF=65) were investigated. CYC led to an upregulation of erythropoiesis, inflammation and myeloid lineage-related modules and a downregulation of lymphoid lineage-related modules. The modular changes resulting from MMF treatment were more modest and included a downregulation of plasmablast module. In the longitudinal analysis, none of the baseline transcript module scores showed predictive significance for FVC% course in the CYC arm. In contrast, in the MMF arm, higher baseline lymphoid lineage modules predicted better subsequent FVC% course, while higher baseline myeloid lineage and inflammation modules predicted worse subsequent FVC% course. CONCLUSION: Consistent with the primary mechanism of action of MMF on lymphocytes, patients with SSc-ILD with higher baseline lymphoid module scores had better FVC% course, while those with higher myeloid cell lineage activation score had poorer FVC% course on MMF.

OBJECTIVE: To assess the predictive significance of blood neutrophil count and the ratio between neutrophil and lymphocyte count (neutrophil-to-lymphocyte ratio [NLR]) for disease severity and mortality in systemic sclerosis (SSc). METHODS: Neutrophil and lymphocyte counts were prospectively measured in the Genetics versus Environment in Scleroderma Outcome Study (GENISOS) and the Scleroderma Lung Study II (SLS II). Forced vital capacity percent predicted (FVC%) and modified Rodnan skin thickness score (MRSS) were used as surrogate measures for disease severity. Longitudinal analyses were performed using generalized linear mixed models. Cox proportional hazards models evaluated the predictive significance of these cell counts for mortality. RESULTS: Of the 447 SSc patients in the GENISOS cohort at the time of analysis, 377 (84.3%) had available baseline blood neutrophil and lymphocyte counts. Higher baseline neutrophil count and NLR predicted lower serially obtained FVC% (b = -4.74, P = 0.009 and b = -2.68, P = 0.028, respectively) and higher serially obtained MRSS (b = 4.07, P < 0.001 and b = 2.32, P < 0.001, respectively). Longitudinal neutrophil and NLR measurements also significantly correlated with lower concurrently obtained FVC% measurements and higher concurrently obtained MRSS. Baseline neutrophil count and NLR predicted increased risk of long-term mortality, even after adjustment for baseline demographic and clinical factors (hazard ratio [HR] 1.42, P = 0.02 and HR 1.48, P < 0.001, respectively). The predictive significance of higher baseline neutrophil count and NLR for declining FVC% and increased long-term mortality was confirmed in the SLS II. CONCLUSION: Higher blood neutrophil count and NLR are predictive of more severe disease course and increased mortality, indicating that these easily obtainable laboratory studies might be a reflection of pathologic immune processes in SSc.