Walter G. Barr

Clinical Applications of Blood-Derived and Marrow-Derived Stem Cells for Nonmalignant Diseases

CONTEXT Stem cell therapy is rapidly developing and has generated excitement and promise as well as confusion and at times contradictory results in the lay and scientific literature. Many types of stem cells show great promise, but clinical application has lagged due to ethical concerns or difficulties in harvesting or safely and efficiently expanding sufficient quantities. In contrast, clinical indications for blood-derived (from peripheral or umbilical cord blood) and bone marrow-derived stem cells, which can be easily and safely harvested, are rapidly increasing. OBJECTIVE To summarize new, nonmalignant, nonhematologic clinical indications for use of blood- and bone marrow-derived stem cells. EVIDENCE ACQUISITION Search of multiple electronic databases (MEDLINE, EMBASE, Science Citation Index), US Food and Drug Administration [FDA] Drug Site, and National Institutes of Health Web site to identify studies published from January 1997 to December 2007 on use of hematopoietic stem cells (HSCs) in autoimmune, cardiac, or vascular diseases. The search was augmented by hand searching of reference lists in clinical trials, review articles, proceedings booklets, FDA reports, and contact with study authors and device and pharmaceutical companies. EVIDENCE SYNTHESIS Of 926 reports identified, 323 were examined for feasibility and toxicity, including those with small numbers of patients, interim or substudy reports, and reports on multiple diseases, treatment of relapse, toxicity, mechanism of action, or stem cell mobilization. Another 69 were evaluated for outcomes. For autoimmune diseases, 26 reports representing 854 patients reported treatment-related mortality of less than 1% (2/220 patients) for nonmyeloablative, less than 2% (3/197) for dose-reduced myeloablative, and 13% (13/100) for intense myeloablative regimens, ie, those including total body irradiation or high-dose busulfan. While all trials performed during the inflammatory stage of autoimmune disease suggested that transplantation of HSCs may have a potent disease-remitting effect, remission duration remains unclear, and no randomized trials have been published. For reports involving cardiovascular diseases, including 17 reports involving 1002 patients with acute myocardial infarction, 16 involving 493 patients with chronic coronary artery disease, and 3 meta-analyses, the evidence suggests that stem cell transplantation performed in patients with coronary artery disease may contribute to modest improvement in cardiac function. CONCLUSIONS Stem cells harvested from blood or marrow, whether administered as purified HSCs or mesenchymal stem cells or as an unmanipulated or unpurified product can, under appropriate conditions in select patients, provide disease-ameliorating effects in some autoimmune diseases and cardiovascular disorders. Clinical trials are needed to determine the most appropriate cell type, dose, method, timing of delivery, and adverse effects of adult HSCs for these and other nonmalignant disorders.

High-dose versus low-dose D-penicillamine in early diffuse systemic sclerosis: Analysis of a two-year, double-blind, randomized, controlled clinical trial

OBJECTIVE To test the hypothesis that systemic sclerosis (SSc) patients taking high-dose D-penicillamine (D-Pen) would have greater softening of skin, lower frequency of renal crisis, and better survival than patients taking low-dose D-Pen. METHODS Seventeen centers enrolled 134 SSc patients with early (< or =18 months) diffuse cutaneous scleroderma into a 2-year, double-blind, randomized comparison of high-dose D-Pen (750-1,000 mg/day) versus low-dose D-Pen (125 mg every other day). All 134 patients were followed up for a mean+/-SD of 4.0+/-1.1 years to assess the frequencies of new-onset scleroderma renal crisis (SRC) and mortality. RESULTS Sixty-eight patients completed 24 months of drug treatment. The course of the modified Rodnan skin thickness score in the 32 high-dose and the 36 low-dose D-Pen completers was not different at 24 months: the skin score dropped 4.8+/-10.3 (mean+/-SD) units in the high-dose group and 6.9+/-8.4 units in the low-dose group (P = 0.384 by t-test; favoring low-dose D-Pen) from 20.4+/-10.3 in the high-dose and 19.9+/-6.6 in the low-dose D-Pen group at study entry. The incidences of SRC and mortality were not different (P > 0.38 by Cox proportional hazards and by chi-square test) in the 66 high-dose patients (8 developed SRC and 8 died) compared with the 68 low-dose patients (10 developed SRC and 12 died). Of the 20 adverse event-related withdrawals, 80% occurred in the high-dose D-Pen group. CONCLUSION The course of the skin score and the frequencies of SRC and mortality in the high-dose D-Pen group were not different from those in the low-dose D-Pen group. Eighty percent of the adverse event-related withdrawals occurred in the high-dose D-Pen patients. Although this study cannot answer the question of whether low-dose D-Pen is effective, it does suggest that there is no advantage to using D-Pen in doses higher than 125 every other day.

Skin thickness score as a predictor and correlate of outcome in systemic sclerosis: High-dose versus low-dose penicillamine trial

OBJECTIVE To study the clinical implications of a skin thickness score > or =20 at first visit and of softening of sclerodermatous skin in a cohort of systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma. METHODS Skin and visceral involvement were assessed in 134 SSc patients with diffuse scleroderma (mean +/- SD duration of SSc 10 +/- 4 months) as they entered a multicenter drug trial and again at 2 years of followup. Advent of mortality and scleroderma renal crisis (SRC) were assessed during a followup of 4.0 +/- 1.1 years (mean +/- SD). Logistic and linear regression were used to examine the relationship of baseline skin score to morbidity, mortality, and visceral involvement and the relationship of changes in skin score to changes in physical examination, laboratory, and functional variables over 2 years. RESULTS A baseline skin score > or =20 was associated with heart involvement at baseline (odds ratio [OR] 3.10, 95% confidence interval [95% CI] 1.25-7.70) and was predictive of mortality (OR 3.59, 95% CI 1.23-10.55) and SRC (OR 10.00, 95% CI 2.21-45.91) over 4 years. Multivariate linear regression demonstrated that a model with skin score at baseline (P = 0.0078) and changes in large joint contractures (P = 0.0072), tender joint counts (P = 0.0119), handspread (P = 0.0242), and Health Assessment Questionnaire disability index (HAQ-DI) (P = 0.0244) explained the change in skin score over 2 years (R2 = 0.567). Multivariate logistic regression demonstrated that the investigators global assessment of improvement was best explained by a model with skin score and HAQ-DI (R2 = 0.455). CONCLUSION A baseline skin score > or =20 was associated with heart involvement at baseline and predicted mortality and SRC over the subsequent 4 years. Improvement in skin score in these patients with diffuse cutaneous scleroderma was associated with improvement in hand function, inflammatory indices, joint contractures, arthritis signs, overall functional ability, and the examining investigators global assessment of improvement.

In situ Expression of Cytokines and Cellular Adhesion Molecules in the Skin of Patients with Systemic Sclerosis

Cytokines and cellular adhesion molecules (CAMs) may play a role in the inflammatory and fibrotic processes underlying systemic sclerosis (SSc). We compared the immunohistological distribution of cytokines and CAMs in skin biopsies from 12 SSc patients and 14 normal (NL) individuals. Among CAMs, vascular cell adhesion molecule-1 (VCAM-1), which mediates leukocyte-endothelial adhesion, showed increased expression on SSc versus NL endothelium and stratum granulosum. P-selectin was up-regulated in SSc versus NL stratum granulosum. The CD44 lymphocyte homing receptor showed the most striking differences between SSc and NL: its expression was increased in SSc stratum granulosum, stratum spinosum, on lymphocytes, and macrophages. Regarding cytokines, interleukin-6 (IL-6) expression was increased on SSc versus NL endothelium and fibroblasts. Tumor necrosis factor-alpha (TNF-alpha) reactivity was more prevalent in SSc than NL stratum granulosum, whereas IL-8 expression was higher on SSc compared to NL endothelium. Some CAMs, such as VCAM-1 and P-selectin, and cytokines, namely TNF-alpha and IL-8, were more commonly found in skin biopsies taken from early (< or = 1 years duration) SSc, while others, such as IL-6, showed up-regulation in the late stage of the disease. The results suggest that certain CAMs and cytokines may play a differential role in both the early, inflammatory, and the late, fibrotic stage of SSc.

Minimally important difference in diffuse systemic sclerosis: results from the d-penicillamine study

Objective: To estimate minimally important differences (MIDs) in scores for the modified Rodnan Skin Score (mRSS) and Health Assessment Questionnaire—Disability Index (HAQ-DI) in a clinical trial on diffuse systemic sclerosis (SSc). Participants and methods: 134 people participated in a 2-year, double-blind, randomised clinical trial comparing efficacy of low-dose and high-dose d-penicillamine in diffuse SSc. At 6, 12, 18 and 24 months, the investigator was asked to rate the change in the patient’s health since entering the study: markedly worsened, moderately worsened, slightly worsened, unchanged, slightly improved, moderately improved or markedly improved. Patients who were rated as slightly improved were defined as the minimally changed subgroup and compared with patients rated as moderately or markedly improved. Results: The MID estimates for the mRSS improvement ranged from 3.2 to 5.3 (0.40–0.66 effect size) and for the HAQ-DI from 0.10 to 0.14 (0.15–0.21 effect size). Patients who were rated to improve more than slightly were found to improve by 6.9–14.2 (0.86–1.77 effect size) on the mRSS and 0.21–0.55 (0.32–0.83 effect size) on the HAQ-DI score. Conclusion: MID estimates are provided for improvement in the mRSS and HAQ-DI scores, which can help in interpreting clinical trials on patients with SSc and be used for sample size calculation for future clinical trials on diffuse SSc.

The Disability Index of the Health Assessment Questionnaire is a predictor and correlate of outcome in the high‐dose versus low‐dose penicillamine in systemic sclerosis trial

OBJECTIVE To explore the clinical implications of a score of > or =1.0 on the Disability Index of the Health Assessment Questionnaire (HAQ DI) at the first patient visit, and to examine the implications of improvement in HAQ DI score over 2 years in a cohort of systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma. METHODS SSc skin and visceral involvement was assessed in 134 SSc patients with diffuse scleroderma (mean +/- SD disease duration of 10 +/- 4 months) when they entered a multicenter drug trial and again 2 years later. Mortality and the occurrence of scleroderma renal crisis were assessed for a mean +/- SD of 4.0 +/- 1.1 years. Logistic and linear regression analyses were used to examine the relationship of the baseline HAQ DI score to morbidity, mortality, and visceral involvement, as well as the relationship of changes in the HAQ DI score to changes in physical examination, laboratory, and functional variables over 2 years. RESULTS A baseline HAQ DI score of > or =1.0 was predictive of mortality (odds ratio 3.22, 95% confidence interval 1.097-9.468) over 4 years. Multivariate linear regression demonstrated that a model which included the erythrocyte sedimentation rate at baseline (P = 0.005) and changes at 2 years in the swollen joint count (P = 0.002), total skin score (P = 0.005), and white blood cell count (P = 0.005) best explained the change in HAQ DI score over 2 years (R2 = 0.528). The HAQ DI score and total skin score at baseline were highly correlated (correlation coefficient 0.368), as were changes in the HAQ DI score and the total skin score over 2 years (correlation coefficient 0.492). Although the HAQ DI score was heavily influenced by hand dysfunction at baseline and at 2 years, improvement (reduction) in the HAQ DI score over 2 years was related to factors other than hand dysfunction. CONCLUSION A baseline HAQ DI score of > or =1.0 predicted mortality over 4 years. Improvement in the HAQ DI score in these patients with diffuse scleroderma was associated with improvement in skin thickening, hand function, oral aperture, lung function, signs of arthritis, serum creatinine level, and the investigators global assessment of improvement. The HAQ DI is a self-administered questionnaire that SSc patients can complete easily and rapidly and that gives the practicing physician important information about prognosis, patient status, and changes in disease course over time.

Hematopoietic stem cell transplantation for autoimmune diseases: what have we learned?

Numerous individuals and institutions throughout the world have contributed to the development of hematopoietic stem cell transplantation (HSCT) for autoimmune diseases. In this review, we will summarize what we have learned at our own institution (Northwestern University), and how it has guided our therapy. An emphasis will be placed on both the scientific basis for the development of autologous hematopoietic stem cell transplantation and a summary of the data in a variety of human diseases.

Autologous non-myeloablative hematopoietic stem cell transplantation in patients with systemic sclerosis

Autologous hematopoietic stem cell transplantation (HSCT) utilizing a myeloablative regimen containing total body irradiation has been performed in patients with systemic sclerosis (SSc), but with substantial toxicity. We, therefore, conducted a phase I non-myeloablative autologous HSCT study in 10 patients with SSc and poor prognostic features. PBSC were mobilized with CY and G-CSF. The PBSC graft was cryopreserved without manipulation and re-infused after the patient was treated with a non-myeloablative conditioning regimen of 200 mg/kg CY and 7.5 mg/kg rabbit antithymocyte globulin. There was a statistically significant improvement of modified Rodnan skin score whereas cardiac (ejection fraction, pulmonary arterial pressure), pulmonary function (DLCO) and renal function (creatinine) remained stable without significant change. One patient with advanced disease died 2 years after the transplant from progressive disease. After median follow-up of 25.5 months, the overall and progression-free survival rates are 90 and 70% respectively. Autologous HSCT utilizing a non-myeloablative conditioning regimen appears to result in improved skin flexibility similar to a myeloablative TBI containing regimen, but without the toxicity and risks associated with TBI.

Autologous non-myeloablative haematopoietic stem cell transplantation for refractory systemic vasculitis.

Objective: For patients with systemic vasculitis (SV) refractory to conventional therapy, new treatment strategies aimed at aggressive induction of remission and relapse prevention are being sought. We herein report our single-centre experience in treating four patients with refractory SV employing non-myeloablative autologous haematopoietic stem cell transplantation (HSCT). Methods: Four patients with refractory SV (two with neurovascular Behcet disease, one with neurovascular Sjögren syndrome, and one with Wegener granulomatosis) were involved in an Institutional Review Board (IRB) and US Food and Drug Administration (FDA) approved phase I clinical trial of high dose chemotherapy and autologous HSCT. Peripheral blood stem cells were mobilised with cyclophosphamide (Cy) and granulocyte-colony stimulating factor (G-CSF). Conditioning regimen consisted of Cy 200 mg/kg and rabbit anti-thymocyte globulin 5.5 mg/kg intravenously (iv). Results: All four patients tolerated HSCT well without transplant related mortality or any significant toxicity. At median follow-up of 28 (range 22–36) months all patients were alive. Three patients (one with Behcet disease, one with Sjögren syndrome, and one with Wegener granulomatosis) entered a sustained remission at 6, 6 and 24 months, respectively, after transplant. They had significant decrease in disease activity and disease or treatment related damage, as measured by the Birmingham Vasculitis Activity Score and Vasculitis Damage Index, respectively. All three patients who achieved remission discontinued immunosuppressive therapy at the time of transplant and have not required treatment since. One patient with Behcet disease and positive for human leukocyte antigen (HLA)-B51 has not improved after HSCT. Conclusion: We suggest non-myeloablative autologous HSCT is an alternative therapy for select patients with SV refractory to conventional immunosuppressive therapies.

Non-myeloablative allogeneic hematopoietic stem cell transplantation for severe systemic sclerosis: graft-versus-autoimmunity without graft-versus-host disease?

Non-myeloablative allogeneic hematopoietic stem cell transplantation for severe systemic sclerosis: graft-versus-autoimmunity without graft-versus-host disease?