Objective. The lack of randomized controlled trials (RCTs) in pulmonary fibrosis in systemic sclerosis (SSc) has hampered an evidence-based approach to treatment. This RCT was undertaken to investigate the effects of intravenous (IV) cyclophosphamide (CYC) followed by azathioprine (AZA) treatment in pulmonary fibrosis in SSc.Methods. Forty-five patients were randomized to receive low-dose prednisolone and 6 infusions (monthly) of CYC followed by oral AZA, or placebo. Primary outcome measures were change in percent predicted forced vital capacity (FVC) and change in single-breath diffusing capacity for carbon monoxide (DLCO). Secondary outcome measures included changes in appearance on high-resolution computed tomography and dyspnea scores. An intent-to-treat statistical analysis was performed.Results. At baseline, there were no significant group differences in factors linked to outcome, including severity of pulmonary fibrosis and autoantibody status. Sixty-two percent of the patients completed the first year of treatment. Withdrawals included 9 patients (6 from the placebo group) with significant decline in lung function, 2 with treatment side effects (both from the active treatment group), and 6 with non-trialrelated comorbidity. No hemorrhagic cystitis or bone marrow suppression was observed. Estimation of the relative treatment effect (active treatment versus placebo) adjusted for baseline FVC and treatment center revealed a favorable outcome for FVC of 4.19%; this between-group difference showed a trend toward statistical significance (P ‫؍‬ 0.08). No improvements in DLCO or secondary outcome measures were identified.Conclusion. This trial did not demonstrate significant improvement in the primary or secondary end points in the active treatment group versus the group receiving placebo. However, for FVC there was a trend toward statistical significance between the 2 groups. This suggests that treatment of pulmonary fibrosis in SSc with low-dose prednisolone and IV CYC followed by AZA stabilizes lung function in a subset of patients with the disease. Therapy was well tolerated with no increase in serious adverse events.

Based on linkages to long-term outcomes, these findings provide support for use of routine spirometry and gas transfer monitoring in patients with SSc-associated ILD, with further evaluation of a composite FVC and DLco end point warranted for trial purposes.

A proportion of people living with common variable immunodeficiency disorders develop granulomatous-lymphocytic interstitial lung disease (GLILD). We aimed to develop a consensus statement on the definition, diagnosis, and management of GLILD. All UK specialist centers were contacted and relevant physicians were invited to take part in a 3-round online Delphi process. Responses were graded as Strongly Agree, Tend to Agree, Neither Agree nor Disagree, Tend to Disagree, and Strongly Disagree, scored +1, +0.5, 0, -0.5, and -1, respectively. Agreement was defined as greater than or equal to 80% consensus. Scores are reported as mean ± SD. There was 100% agreement (score, 0.92 ± 0.19) for the following definition: "GLILD is a distinct clinico-radio-pathological ILD occurring in patients with [common variable immunodeficiency disorders], associated with a lymphocytic infiltrate and/or granuloma in the lung, and in whom other conditions have been considered and where possible excluded." There was consensus that the workup of suspected GLILD requires chest computed tomography (CT) (0.98 ± 0.01), lung function tests (eg, gas transfer, 0.94 ± 0.17), bronchoscopy to exclude infection (0.63 ± 0.50), and lung biopsy (0.58 ± 0.40). There was no consensus on whether expectant management following optimization of immunoglobulin therapy was acceptable: 67% agreed, 25% disagreed, score 0.38 ± 0.59; 90% agreed that when treatment was required, first-line treatment should be with corticosteroids alone (score, 0.55 ± 0.51).

Objective. Connective tissue growth factor (CTGF; CCN2) is overexpressed in systemic sclerosis (SSc) and has been hypothesized to be a key mediator of the pulmonary fibrosis frequently observed in this disease. CTGF is induced by transforming growth factor ␤ (TGF␤) and is a mediator of some profibrotic effects of TGF␤ in vitro. This study was undertaken to investigate the role of CTGF in enhanced expression of type I collagen in bleomycin-induced lung fibrosis, and to delineate the mechanisms of action underlying the effects of CTGF on Col1a2 (collagen gene type I ␣2) in this mouse model and in human pulmonary fibroblasts.Methods. Transgenic mice that were carrying luciferase and ␤-galactosidase reporter genes driven by the Col1a2 enhancer/promoter and the CTGF promoter, respectively, were injected with bleomycin to induce lung fibrosis (or saline as control), and the extracted pulmonary fibroblasts were incubated with CTGF blocking agents. In vitro, transient transfection, promoter/ reporter constructs, and electrophoretic mobility shift assays were used to determine the mechanisms of action of CTGF in pulmonary fibroblasts.Results. In the mouse lung tissue, CTGF expression and promoter activity peaked 1 week after bleomycin challenge, whereas type I collagen expression and Col1a2 promoter activity peaked 2 weeks postchallenge. Fibroblasts isolated from the mouse lungs 14 days after bleomycin treatment retained a profibrotic expression pattern, characterized by greatly elevated levels of type I collagen and CTGF protein and increased promoter activity. In vitro, inhibition of CTGF by specific small interfering RNA and neutralizing antibodies reduced the collagen protein expression and Col1a2 promoter activity. Moreover, in vivo, anti-CTGF antibodies applied after bleomycin challenge significantly reduced the Col1a2 promoter activity by ϳ25%. The enhanced Col1a2 promoter activity in fibroblasts from bleomycintreated lungs was partly dependent on Smad signaling, whereas CTGF acted on the Col1a2 promoter by a mechanism that was independent of the Smad binding site, but was, instead, dependent on the ERK-1/2 and JNK MAPK pathways. The CTGF effect was mapped to the proximal promoter region surrounding the inverted CCAAT box, possibly involving CREB and c-Jun. In human lung fibroblasts, the human COL1A2 promoter responded in a similar manner, and the mechanisms of action also involved ERK-1/2 and JNK signaling.Conclusion. Our results clearly define a direct profibrotic effect of CTGF and demonstrate its contribution to lung fibrosis through transcriptional activation

Rationale: The impact of COVID-19 on patients with Interstitial Lung Disease (ILD) has not been established. Objectives: To assess outcomes in patients with ILD hospitalized for COVID-19 versus those without ILD in a contemporaneous age, sex and comorbidity matched population. Methods: An international multicenter audit of patients with a prior diagnosis of ILD admitted to hospital with COVID-19 between 1 March and 1 May 2020 was undertaken and compared with patients, without ILD obtained from the ISARIC 4C cohort, admitted with COVID-19 over the same period. The primary outcome was survival. Secondary analysis distinguished IPF from non-IPF ILD and used lung function to determine the greatest risks of death. Measurements and Main Results: Data from 349 patients with ILD across Europe were included, of whom 161 were admitted to hospital with laboratory or clinical evidence of COVID-19 and eligible for propensity-score matching. Overall mortality was 49% (79/161) in patients with ILD with COVID-19. After matching ILD patients with COVID-19 had higher mortality (HR 1.60, Confidence Intervals 1.17-2.18 p=0.003) compared with age, sex and comorbidity matched controls without ILD. Patients with a Forced Vital Capacity (FVC) of <80% had an increased risk of death versus patients with FVC ≥80% (HR 1.72, 1.05-2.83). Furthermore, obese patients with ILD had an elevated risk of death (HR 2.27, 1.39−3.71). Conclusions: Patients with ILD are at increased risk of death from COVID-19, particularly those with poor lung function and obesity. Stringent precautions should be taken to avoid COVID-19 in patients with ILD.

Objective.Biomarkers of progression of interstitial lung disease (ILD) are needed to allow early therapeutic intervention in patients with scleroderma-associated disease (SSc-ILD).Methods.A panel of 8 serum cytokines [interleukin 6 (IL-6), IL-8, IL-10, CCL2, CXCL10, vascular endothelial growth factor, fibroblast growth factor 2, and CX3CL1] was assessed by Luminex bead technology in exploratory cohorts of 74 patients with SSc and 58 patients with idiopathic pulmonary fibrosis (IPF). Mortality and significant lung function decline [forced vital capacity (FVC) ≥ 10%; DLCO ≥ 15%] from date of serum collection were evaluated by proportional hazards analysis. Based on these findings, the prognostic value of serum IL-6, evaluated by ELISA, was assessed in a larger test cohort of 212 patients with SSc-ILD.Results.In the exploratory cohort, only serum IL-6 was an independent predictor of DLCO decline in both IPF and SSc-ILD. The IL-6 threshold level most predictive of DLCO decline within a year was 7.67 pg/ml. In the larger test cohort, serum IL-6 > 7.67 pg/ml was predictive of decline in FVC (HR 2.58 ± 0.98, p = 0.01) and in DLCO (HR 3.2 ± 1.7, p = 0.02) within the first year, and predictive of death within the first 30 months (HR 2.69 ± 0.96, p = 0.005). When stratified according to severity (FVC < 70%), serum IL-6 > 7.67 pg/ml was predictive of functional decline or death within the first year in patients with milder disease (OR 3.1, 95% CI 1.4–7.2, p = 0.007), but not in those with severe ILD.Conclusion.In SSc-ILD, serum IL-6 levels appear to be predictive of early disease progression in patients with mild ILD, and could be used to target treatment in this group, if confirmed by prospective studies.

Previous attempts to delete type II TGFbeta receptor (TbetaRII) in fibroblasts have precluded examination of adult mice due to early mortality. We have selectively deleted TbetaRII postnatally in differentiated connective tissue fibroblasts using an inducible Cre-Lox strategy. Tamoxifen-dependent Cre recombinase linked to a fibroblast-specific regulatory sequence from the proalpha2(I)collagen gene permitted deletion of floxed TbetaRII alleles. After postnatal deletion of TbetaRII in fibroblasts, healing of excisional skin wounds in adults showed markedly attenuated dermal scar formation, defective wound contraction and enhanced epidermal proliferation. These findings support a pivotal role for transforming growth factor beta (TGFbeta) signalling in fibroblasts in regulating normal skin wound healing. Explanted dermal fibroblasts from TbetaRII-null-fib mice showed impaired migration and did not generate normal contractile biomechanical forces in fixed collagen gels nor develop alpha-smooth muscle antigen-rich stress fibers in response to TGFbeta1. Surprisingly, some TGFbeta-regulated proteins, including connective tissue growth factor (CTGF), were basally upregulated in TbetaRII-null fibroblasts and this was dependent on extracellular signal-regulated kinase 1/2 activity in these cells. This suggests that other intracellular pathways regulating CTGF expression may partially compensate for disruption of TGFbeta signalling in fibroblasts. Together, our data confirm that expression of TbetaRII in differentiated dermal fibroblasts is essential for normal wound healing and demonstrate a critical role in the development and function of myofibroblasts.

Intact TGFβ signaling in resident pulmonary fibroblasts is essential for pulmonary fibrosis to develop. Our data support a key regulatory role of these cells in determining fibrocyte recruitment and myofibroblast differentiation.