Autologous stem cell transplantation improves cardiopulmonary exercise testing outcomes in systemic sclerosis patients.

OBJECTIVES: Autologous haematopoietic stem cell transplantation (AHSCT) is a disease-modifying treatment for patients with severe SSc. Here, we aimed at assessing cardiopulmonary function outcomes of SSc patients after AHSCT. METHODS: Twenty-seven SSc adult patients treated with AHSCT were included in this retrospective study. Most had the diffuse cutaneous subset (93%) and pulmonary involvement (85%). Before and 12 months after AHSCT, patients underwent cardiopulmonary exercise testing, transthoracic echocardiography, pulmonary function test with diffusing capacity for carbon monoxide (DLCO), 6-min walk test (6MWT) and quality of life evaluations. RESULTS: After AHSCT, the peak VO2 increased from 954 to 1029 ml/min (P = 0.02), the percentage of predicted peak VO2 increased from 48.9 to 53.5 m (P = 0.01), and the distance measured by the 6MWT increased from 445 to 502 m (P = 0.01), compared with baseline. Improvements in peak VO2 correlated positively with improvements in 6MWT distance, and negatively with a decrease in resting heart rate. At baseline, patients with DLCO >70% had higher peak VO2 values than those with DLCO <70% (P = 0.04), but after AHSCT all patients showed improved VO2 values, regardless of baseline DLCO levels. Increases in VO2 levels after AHSCT positively correlated with increases in the physical component scores of the Short Form-36 quality of life questionnaire (r = 0.70; P = 0.0003). CONCLUSION: AHSCT improves the aerobic capacity of SSc patients probably reflecting combined increments in lungs, skeletal muscle and cardiac function.

Autologous hematopoietic stem cell transplantation promotes connective tissue remodeling in systemic sclerosis patients.

BACKGROUND: Autologous hematopoietic stem cell transplantation (AHSCT) treats patients with severe and progressive systemic sclerosis (SSc). However, basic mechanisms associated with the therapeutic efficacy of the procedure are not entirely understood. We aimed to evaluate how AHSCT affects skin fibrosis in SSc patients. METHODS: Clinical data, serum, and skin samples from 39 SSc patients who underwent AHSCT were retrospectively evaluated. Skin biopsies were analyzed by immunohistochemistry with anti-MMP-1, -MMP-2, -MMP-3, -MMP-9, -TIMP-1, -α-SMA, -TGF-ß, and -NF-κB p65 antibodies, and stained with hematoxylin and eosin and picrosirius red to assess skin thickness and collagen density, respectively. Serum samples were evaluated by Multiplex Assay for COL1A1, COL4A1, FGF-1, MMP-1, MMP-3, MMP-12, MMP-13, PDGF-AA, PDGF-BB, S100A9, and TIMP-1 levels and compared to healthy controls. RESULTS: After AHSCT, SSc patients showed clinical improvement in skin involvement, assessed by modified Rodnan's skin score (mRSS). Histologically, collagen density and skin thickness decreased after AHSCT. Immunohistochemical analyses showed increased expression of MMP-2, MMP-3, MMP-9, and TIMP-1 after AHSCT, whereas expression of NF-κB p65 decreased. At baseline, serum levels of COL4A1 and S100A9 were higher than in healthy controls. Serum levels of S100A9 normalized after AHCST in SSc patients compared to controls. Serum levels of PDGF-AA, PDGF-BB, TIMP-1, and MMP-1 decreased, while COL1A1 increased after AHSCT in SSc patients. No changes were detected in MMP-3, MMP-12, MMP-13, and FGF-1 serum levels after AHSCT. CONCLUSIONS: Our results suggest that the therapeutic effects of AHSCT on skin fibrosis are related to changes in molecules associated with connective tissue maintenance and inflammation in SSc.

Autologous hematopoietic stem cell transplantation modifies specific aspects of systemic sclerosis-related microvasculopathy.

Objective: Autologous hematopoietic stem cell transplantation (AHSCT) is a therapeutic option for patients with severe and progressive systemic sclerosis (SSc). Here, we aimed to investigate how AHSCT affects the vasculopathy of SSc patients. Methods: Twenty-seven SSc patients were retrospectively assessed, before and after AHSCT, for vessel morphology (nailfold capillaroscopy), skin expression of endothelial markers and serum levels of markers of inflammation, angiogenesis and endothelial activation. Skin biopsies were analyzed by immunohistochemistry (IHC) for expression of CD31, VE-cadherin, E-selectin, angiopoietin-1 (Ang1), angiopoietin-2 (Ang2), Tie-2, vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor receptor 2 (VEGFR2), and endothelin-1 before and 12 months post-AHSCT. Serum samples from SSc patients were assessed before and up to 36 months after AHSCT for IL-6, von Willebrand factor (vWF), CXC Motif Chemokine Ligand 8 (CXCL8), Endothelin-1, epidermal growth factor (EGF), VEGFA, Pentraxin-3, Intercellular Adhesion Molecule 1 (ICAM-1), E-selectin, P-selectin, Thrombomodulin and IL-18 levels, and compared to healthy control samples. Results: On nailfold capillaroscopy, the number of capillaries increased at 1 year, while giant capillaries decreased at 6 months and 1 year after AHSCT. In the skin biopsies, expression of E-selectin notably decreased and Ang1 increased after AHSCT. At baseline, all vascular markers evaluated in the serum were significantly higher in SSc patients when compared to healthy controls, except for ICAM-1. When compared at different time points after AHSCT, Thrombomodulin, Pentraxin-3, vWF, and IL-18 levels remained generally stable at high levels until 36 months after AHSCT. Conclusion: Our results suggest that AHSCT contributes to improvements of the vessel morphology and dermal microvasculopathy, but does not normalize elevated levels of serum vascular markers in SSc patients. Additional vascular therapeutic approaches might contribute to more effectively treat the endothelial injury.

Hematopoietic stem cell transplantation reverses white matter injury measured by diffusion-tensor imaging (DTI) in sickle cell disease patients.

Brain injury in sickle cell disease (SCD) comprises a wide spectrum of neurological damage. Neurocognitive deficits have been described even without established neurological lesions. DTI is a rapid, noninvasive, and non-contrast method that enables detection of normal-appearing white matter lesions not detected by conventional magnetic resonance imaging (MRI). The aim of the study was to evaluate if stem cell transplantation can revert white matter lesions in patients with SCD. Twenty-eight SCD patients were evaluated with MRI and DTI before and after allogeneic hematopoietic stem cell transplantation (HSCT), compared with 26 healthy controls (HC). DTI metrics included fractional anisotropy (FA), mean diffusivity (MD), radial (RD), and axial (AD) diffusivity maps, global efficiency, path length, and clustering coefficients. Compared to HC, SCD patients had a lower FA (p = 0.0086) before HSCT. After HSCT, FA increased and was not different from healthy controls (p = 0.1769). Mean MD, RD, and AD decreased after HSCT (p = 0.0049; p = 0.0029; p = 0.0408, respectively). We confirm previous data of white matter lesions in SCD and present evidence that HSCT promotes recovery of brain injury with potential improvement of brain structural connectivity.

Autologous haematopoietic stem cell transplantation restores the suppressive capacity of regulatory B cells in systemic sclerosis patients.

OBJECTIVES: The rationale of autologous haematopoietic stem cell transplantation (AHSCT) for autoimmune diseases is that high-dose immunosuppression eradicates autoreactive T and B cells and the infused autologous haematopoietic stem cells promote reconstitution of a naïve and self-tolerant immune system. The aim of this study was to evaluate the reconstitution of different B cell subsets, both quantitatively and functionally, in SSc patients treated with AHSCT. METHODS: Peripheral blood was harvested from 22 SSc patients before transplantation and at 30, 60, 120, 180 and 360 days post-AHSCT. Immunophenotyping of B cell subsets, B cell cytokine production, signalling pathways and suppressive capacity of regulatory B cells (Bregs) were assessed by flow cytometry. RESULTS: Naïve B cell frequencies increased from 60 to 360 days post-AHSCT compared with pre-transplantation. Conversely, memory B cell frequencies decreased during the same period. Plasma cell frequencies transiently decreased at 60 days post-AHSCT. IL-10-producing Bregs CD19+CD24hiCD38hi and CD19+CD24hiCD27+ frequencies increased at 180 days. Moreover, the phosphorylation of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase increased in B cells reconstituted post-AHSCT. Notably, CD19+CD24hiCD38hi Bregs recovered their ability to suppress production of Th1 cytokines by CD4+ T cells at 360 days post-AHSCT. Finally, IL-6 and TGF-ß1-producing B cells decreased following AHSCT. CONCLUSION: Taken together, these results suggest improvements in immunoregulatory and anti-fibrotic mechanisms after AHSCT for SSc, which may contribute to re-establishment of self-tolerance and clinical remission.

Immune rebound associates with a favorable clinical response to autologous HSCT in systemic sclerosis patients.

To evaluate the immunological mechanisms associated with clinical outcomes after autologous hematopoietic stem cell transplantation (AHSCT), focusing on regulatory T- (Treg) and B- (Breg) cell immune reconstitution, 31 systemic sclerosis (SSc) patients underwent simultaneous clinical and immunological evaluations over 36-month posttransplantation follow-up. Patients were retrospectively grouped into responders (n = 25) and nonresponders (n = 6), according to clinical response after AHSCT. Thymic function and B-cell neogenesis were respectively assessed by quantification of DNA excision circles generated during T- and B-cell receptor rearrangements. At the 1-year post-AHSCT evaluation of the total set of transplanted SSc patients, thymic rebound led to renewal of the immune system, with higher T-cell receptor (TCR) diversity, positive correlation between recent thymic emigrant and Treg counts, and higher expression of CTLA-4 and GITR on Tregs, when compared with pretransplant levels. In parallel, increased bone marrow output of newly generated naive B-cells, starting at 6 months after AHSCT, renovated the B-cell populations in peripheral blood. At 6 and 12 months after AHSCT, Bregs increased and produced higher interleukin-10 levels than before transplant. When the nonresponder patients were evaluated separately, Treg and Breg counts did not increase after AHSCT, and high TCR repertoire overlap between pre- and posttransplant periods indicated maintenance of underlying disease mechanisms. These data suggest that clinical improvement of SSc patients is related to increased counts of newly generated Tregs and Bregs after AHSCT as a result of coordinated thymic and bone marrow rebound.

Microvascular Complications in Type 1 Diabetes: A Comparative Analysis of Patients Treated with Autologous Nonmyeloablative Hematopoietic Stem-Cell Transplantation and Conventional Medical Therapy.

OBJECTIVE: To explore the impact on microvascular complications, long-term preservation of residual B-cell function and glycemic control of patients with type 1 diabetes treated with autologous nonmyeloablative hematopoietic stem-cell transplantation (AHST) compared with conventional medical therapy (CT). RESEARCH DESIGN AND METHODS: Cross-sectional data of patients treated with AHST were compared with patients who received conventional therapy from the Brazilian Type 1 Diabetes Study Group, the largest multicenter observational study in type 1 diabetes mellitus in Brazil. Both groups of patients had diabetes for 8 years on average. An assessment comparison was made on the presence of microvascular complications, residual function of B cell, A1c, and insulin dose of the patients. RESULTS: After a median of 8 years of diagnosis, none of the AHST-treated patients (n = 24) developed microvascular complications, while 21.5% (31/144) had at least one (p < 0.005) complication in the CT group (n = 144). Furthermore, no case of nephropathy was reported in the AHST group, while 13.8% of CT group (p < 0.005) developed nephropathy during the same period. With regard of residual B-cell function, the percentage of individuals with predicted higher C-peptide levels (IDAA1C ≤ 9) was about 10-fold higher in the AHST group compared with CT (75 vs. 8.3%) (p < 0.001) group. Among AHST patients, 54.1% (13/24) had the HbA1c < 7.0 compared with 13.1% in the CT (p < 0.001) group. CONCLUSION: Patients with newly diagnosed type 1 diabetes treated with AHST presented lower prevalence of microvascular complications, higher residual B-cell function, and better glycemic control compared with the CT group.

Immunological Balance Is Associated with Clinical Outcome after Autologous Hematopoietic Stem Cell Transplantation in Type 1 Diabetes.

Autologous hematopoietic stem cell transplantation (AHSCT) increases C-peptide levels and induces insulin independence in patients with type 1 diabetes. This study aimed to investigate how clinical outcomes may associate with the immunological status, especially concerning the balance between immunoregulation and autoreactivity. Twenty-one type 1 diabetes patients were monitored after AHSCT and assessed every 6 months for duration of insulin independence, C-peptide levels, frequencies of islet-specific autoreactive CD8+ T cells (CTL), regulatory lymphocyte subsets, thymic function, and T-cell repertoire diversity. In median follow-up of 78 (range 15-106) months, all patients became insulin-independent, resuming insulin after median of 43 (range 6-100) months. Patients were retrospectively divided into short- or prolonged-remission groups, according to duration of insulin independence. For the entire follow-up, CD3+CD4+ T-cell numbers remained lower than baseline in both groups, whereas CD3+CD8+ T-cell levels did not change, resulting in a CD4/CD8 ratio inversion. Memory CTL comprehended most of T cells detected on long-term follow-up of patients after AHSCT. B cells reconstituted to baseline levels at 2-3 months post-AHSCT in both patient groups. In the prolonged-remission-group, baseline islet-specific T-cell autoreactivity persisted after transplantation, but regulatory T cell counts increased. Patients with lower frequencies of autoreactive islet-specific T cells remained insulin-free longer and presented greater C-peptide levels than those with lower frequencies of these cells. Therefore, immune monitoring identified a subgroup of patients with superior clinical outcome of AHSCT. Our study shows that improved immunoregulation may balance autoreactivity endorsing better metabolic outcomes in patients with lower frequencies of islet-specific T cells. Development of new strategies of AHSCT is necessary to increase frequency and function of T and B regulatory cells and decrease efficiently autoreactive islet-specific T and B memory cells in type 1 diabetes patients undergoing transplantation.