Clinical and Molecular Findings After Autologous Stem Cell Transplantation or Cyclophosphamide for Scleroderma: Handling Missing Longitudinal Data

Autologous hematopoietic stem cell transplant for systemic sclerosis associated interstitial lung disease

PURPOSE OF REVIEW

Over the last 25 years, the role of autologous hematopoietic stem cell transplant (HSCT) in the treatment of diffuse cutaneous systemic sclerosis (dcSSc) has been elucidated. However, multiple critical questions remain regarding this therapy. Of particular interest is the role of HSCT in the treatment of systemic sclerosis (SSc)-associated interstitial lung disease since this is the leading cause of death in SSc.

RECENT FINDINGS

Most clinical trials and observational studies of HSCT for the treatment of dcSSc have reported pulmonary outcomes as secondary outcomes, Also, most studies have excluded patients with significant pulmonary function impairment. Despite these limitations, there is increasing evidence that suggests that HSCT leads to interstitial lung disease stabilization and possibly improvement of lung function based on pulmonary function tests and imaging.

SUMMARY

HSCT has demonstrated improved long-term outcomes compared to conventional therapies for dcSSC. Future research is needed to refine or expand patient selection, optimize conditioning regimens, and evaluate the potential role of maintenance immunosuppression. We recommend an increased focus on interstitial lung disease since this is the primary cause of death in SSc.

Myeloablation Followed by Hematopoietic Stem Cell Transplantation and Long-Term Normalization of Systemic Sclerosis Molecular Signatures

OBJECTIVE

In the randomized Scleroderma: Cyclophosphamide or Transplantation (SCOT) trial, myeloablation, followed by hematopoietic stem cell transplantation (HSCT), led to the normalization of systemic sclerosis (SSc) peripheral blood cell (PBC) gene expression signature at the 26-month visit. Herein, we examined long-term molecular changes ensuing 54 months after randomization for individuals receiving an HSCT or 12 months of intravenous cyclophosphamide (CYC).

METHODS

Global PBC transcript studies were performed in study participants at pretreatment baseline and at 38 months and 54 months after randomization, as well as in healthy controls using Illumina HT-12 arrays.

RESULTS

Thirty (HSCT = 19 and CYC = 11) participants had 38-month samples available, and 26 (HSCT = 16 and CYC = 11) had 54-month samples available. In the paired comparison to baseline, a significant down-regulation of interferon modules and an up-regulation of cytotoxic/natural killer module were observed at the 38-month and 54-month visits in the HSCT arm, indicating a long-term normalization of baseline SSc gene expression signature. No differentially expressed modules were detected in the CYC arm. In comparison to samples from healthy controls, 38-month visit samples in the HSCT arm showed an up-regulation of B cell and plasmablast modules and a down-regulation of myeloid and inflammation modules. Importantly, 54-month HSCT samples did not show any differentially expressed modules compared to healthy control samples, suggesting completion of immune reconstitution. Participants in the CYC arm continued to show an SSc transcript signature in comparison to controls at both time points.

CONCLUSION

Paralleling the observed clinical benefit, HSCT leads to durable long-term normalization of the molecular signature in SSc, with completion of immune resetting to 54 months after HSCT.

Esophageal motility in systemic sclerosis before and after autologous hematopoietic cell transplantation

INTRODUCTION

Systemic sclerosis (SSc) is associated with esophageal dysmotility. Autologous hematopoietic cell transplantation (HCT) results in improvement of skin tightness and lung function. Whether esophageal motility improves after HCT is unknown.

METHODS

Esophageal motility was studied using high-resolution esophageal manometry in 21 SSc patients before and at multiple time points after autologous HCT. Median posttransplant follow-up was 2 years (range, 6 months to 5 years).

RESULTS

Prior to HCT, all 21 patients had abnormal motility-10 (48%) had unmeasurable and 11 (52%) had measurable peristalsis. Manometric diagnosis in the former 10 patients was "absent contractility" and in the latter 11 patients "ineffective esophageal motility (IEM)." After HCT, among the 10 patients with absent contractility, 9 continued to have absent contractility and one demonstrated weak measurable peristalsis. Of the 11 patients with IEM, 5 experienced SSc relapse, and 2 out of these 5 patients developed absent contractility. Among the 6 non-relapsed patients, 4 continued to have IEM, and 2 developed normal motility.

CONCLUSIONS

HCT appears to have no beneficial effect on motility in patients with unmeasurable peristalsis. In patients with measurable peristalsis, HCT appears to stabilize and in some normalize motility, unless relapse occurs. Key Points • In patients with systemic sclerosis, esophageal dysmotility is a significant contributor to morbidity and so far, there has been no data describing the effects of hematopoietic cell transplantation on esophageal motility. • Our work demonstrated that in patients with systemic sclerosis and unmeasurable esophageal peristalsis prehematopoietic cell transplantation, there was no measurable beneficial effect of transplantation on esophageal motility. • In patients with systemic sclerosis and measurable peristalsis prehematopoietic cell transplantation, esophageal motility stabilized, except in relapsed patients.

Hematopoietic Cell Transplantation for Systemic Sclerosis-A Review

Systemic sclerosis (SSc) is an autoimmune, multi-organ, connective tissue disease associated with significant morbidity and mortality. Conventional immunosuppressive therapies demonstrate limited efficacy. Autologous hematopoietic stem cell transplantation (HCT) is more efficacious but carries associated risks, including treatment-related mortality. Here, we review HCT as a treatment for SSc, its efficacy and toxicity in comparison to conventional therapies, and the proposed mechanisms of action. Furthermore, we discuss the importance of and recent developments in patient selection. Finally, we highlight the knowledge gaps and future work required to further improve patient outcomes.

Lymphocyte subset abnormalities in early severe scleroderma favor a Th2 phenotype and are not altered by prior immunosuppressive therapy

OBJECTIVES

The Scleroderma: Cyclophosphamide or Transplantation (SCOT) trial compared hematopoietic stem cell transplant to CYC treatment in patients with early SSc with progressive skin and lung or kidney involvement. Here we describe lymphocyte phenotype abnormalities at study entry and the relation to prior DMARD therapy.

METHODS

Lymphocyte subsets (n = 26) measured by flow cytometry were compared in 123 heathy controls and 71 SCOT participants, including those given (n = 57) or not given (n = 14) DMARDs within 12 months of randomization.

RESULTS

Compared with healthy controls, individuals with SSc showed significant reductions in central memory CD8 T cells, activated total and CD4 T cells, γ/δ T cells, memory B cells, myeloid and plasmacytoid dendritic cells and FOXP3+CD25+ Treg cells and increases in naïve CD4 T cells, effector memory CD4 T cells and effector CD8 T cells. A greater bias towards a IL-4+ Th2/T cytotoxic 2 (Tc2) phenotype based on the Th2:Th1 CD4 ratio and Tc2:Tc1 CD8 T cells was also found. Notably, no difference in any lymphocyte subset was observed between those given or not given prior DMARDs.

CONCLUSIONS

In patients with early, severe SSc, significant lymphocyte subset abnormalities were observed. Prior treatment with immunosuppressive therapy did not impact the immunophenotype, suggesting that lymphocyte disturbances in scleroderma appeared to be due to the disease itself.

TRIAL REGISTRATION

ClinicalTrials.gov (https://clinicaltrials.gov), NCT00114530.