High-dose immunosuppression and hematopoietic stem cell transplantation in autoimmune disease: clinical review

Current State and Issues of Regenerative Medicine for Rheumatic Diseases

The prognosis of rheumatic diseases is generally better than that of malignant diseases. However, some cases with poor prognoses resist conventional therapies and cause irreversible functional and organ damage. In recent years, there has been much research on regenerative medicine, which uses stem cells to restore the function of missing or dysfunctional tissues and organs. The development of regenerative medicine is also being attempted in rheumatic diseases. In diseases such as systemic sclerosis (SSc), systemic lupus erythematosus (SLE), and rheumatoid arthritis, hematopoietic stem cell transplantation has been attempted to correct and reconstruct abnormalities in the immune system. Mesenchymal stem cells (MSCs) have also been tried for the treatment of refractory skin ulcers in SSc using the ability of MSCs to differentiate into vascular endothelial cells and for the treatment of systemic lupus erythematosus SLE using the immunosuppressive effect of MSCs. CD34-positive endothelial progenitor cells (EPCs), which are found in the mononuclear cell fraction of bone marrow and peripheral blood, can differentiate into vascular endothelial cells at the site of ischemia. Therefore, EPCs have been used in research on vascular regeneration therapy for patients with severe lower limb ischemia caused by rheumatic diseases such as SSc. Since the first report of induced pluripotent stem cells (iPSCs) in 2007, research on regenerative medicine using iPSCs has been actively conducted, and their application to rheumatic diseases is expected. However, there are many safety issues and bioethical issues involved in regenerative medicine research, and it is essential to resolve these issues for practical application and spread of regenerative medicine in the future. The environment surrounding regenerative medicine research is changing drastically, and the required expertise is becoming higher. This paper outlines the current status and challenges of regenerative medicine in rheumatic diseases.

Remission is not maintained over 2 years with hematopoietic stem cell transplantation for rheumatoid arthritis: A systematic review with meta-analysis

BACKGROUND

Hematopoietic stem cell (HSC) transplantation (HSCT) is being accepted as a standard of care in various inflammatory diseases. The treatment of rheumatoid arthritis (RA) has been closely evolving with the understanding of disease pathogenesis. With the rising resistance to the traditional disease-modifying anti-rheumatic drugs and targeted biological therapy, researchers are in pursuit of other methods for disease management. Since the ultimate goal of the ideal treatment of RA is to restore immune tolerance, HSCT attracts much attention considering its reparative, paracrine, and anti-inflammatory effects. However, a systematic review of studies on HSCT in RA is lacking.

AIM

To investigate the role of HSCT in the management of RA.

METHODS

A detailed search of PubMed, Scopus, EMBASE, Cochrane, and the Web of Science databases was made to identify the relevant articles till September 2020 following Cochrane and PRISMA guidelines. We extracted data including the number of patients, source of hematopoietic stem cells, their mobilization and conditioning regimens, results, and complications from the eligible studies. Results were dichotomized into success (ACR 50/70) and failure (ACR 20) based on the improvement from baseline characteristics. The methodological quality of the included studies was also assessed. Analysis was performed using OpenMeta[Analysis] software.

RESULTS

We included 17 studies (1 randomized controlled trial, 11 prospective, and 5 retrospective studies) with 233 patients for analysis. HSCT provided a significantly beneficial overall improvement in the clinical grades of ACR criteria (Z = 11.309, P < 0.001). However, the remission was noted only till 24 mo and later on the significance of the result was lost (Z = 1.737, P = 0.082). A less than 1% treatment-related mortality was noted from the included studies. No major drug-related toxicities were noted in any of the included studies. All patients who underwent allogeneic HSCT received immunosuppression in the conditioning regimen to counteract the graft-vs-host reaction which made them vulnerable to infections. It is noted that the source of hematopoietic stem cells did not play a role in altering the functional outcome and both autologous (Z = 9.972, P < 0.001) and allogenic (Z = 6.978, P < 0.001) sources produced significant improvement in the outcome compared to the pre-operative state despite having a significant heterogeneity among the studies reporting them (I² = 99.4, P < 0.001).

CONCLUSION

Although the available literature is encouraging towards the use of HSCT in refractory cases with significant improvement from baseline till 2 years, the inclusion of HSCT into the standard of care of RA needs further exploration.

The avoidance of G-CSF and the addition of prophylactic corticosteroids after autologous stem cell transplantation for multiple myeloma patients appeal for the at-home setting to reduce readmission for neutropenic fever

BACKGROUND

Autologous stem cell transplantation (ASCT) remains the standard of care for young multiple myeloma (MM) patients; indeed, at-home ASCT has been positioned as an appropriate therapeutic strategy. However, despite the use of prophylactic antibiotics, neutropenic fever (NF) and hospital readmissions continue to pose as the most important limitations in the outpatient setting. It is possible that the febrile episodes may have a non-infectious etiology, and engraftment syndrome could play a more significant role. The aim of this study was to analyze the impact of both G-CSF withdrawal and the addition of primary prophylaxis with corticosteroids after ASCT.

METHODS

Between January 2002 and August 2018, 111 MM patients conditioned with melphalan were managed at-home beginning +1 day after ASCT. Three groups were established: Group A (n = 33) received standard G-CSF post-ASCT; group B (n = 32) avoided G-CSF post-ASCT; group C (n = 46) avoided G-CSF yet added corticosteroid prophylaxis post-ASCT.

RESULTS

The incidence of NF among the groups was reduced (64%, 44%, and 24%; P<0.001), with a non-significant decrease in hospital readmissions as well (12%, 6%, and 2%; P = 0.07). The most important variables identified for NF were: HCT-CI >2 (OR 6.1; P = 0.002) and G-CSF avoidance plus corticosteroids (OR 0.1; P<0.001); and for hospital readmission: age ≥60 years (OR 14.6; P = 0.04) and G-CSF avoidance plus corticosteroids (OR 0.07; P = 0.05).

CONCLUSIONS

G-CSF avoidance and corticosteroid prophylaxis post ASCT minimize the incidence of NF in MM patients undergoing at-home ASCT. This approach should be explored in a prospective randomized clinical trial.

Innovative strategies minimize engraftment syndrome in multiple myeloma patients with novel induction therapy following autologous hematopoietic stem cell transplantation

Autologous stem cell transplantation (PBSCT) is standard for young patients in MM and its TRM has decreased after the 2000s. Bortezomib and immunomodulatory agents (IMiDs) in MM have improved the outcome. However, they seem to boost pro-inflammatory stage increasing the incidence of engraftment syndrome (ES). Favorable factors in PBSCT such as G-CSF could increase inflammatory stage during transplant. Corticosteroids have shown an excellent response of ES and some authors propose them as prophylaxis for ES. The aim was to analyze the impact of G-CSF avoidance and corticosteroids' prophylaxis in 170 patients diagnosed of MM treated with bortezomib/IMiDs that underwent PBSCT. We established three groups: Group-I [(G-CSF_administration), 60 patients (35%)], group-II [(nonG-CSF), 60 patients (35%)] and group-III [(nonG-CSF plus corticosteroid's prophylaxis), 50 patients (30%)]. A decreased ES incidence among groups was observed: 62, 42, and 22% (P < 0.0001). The incidence of symptoms mimicking a capillary leak syndrome associated with ES dropped: 43, 32, and 0% (P = 0.03). The G-CSF avoidance and corticosteroids had impact over admission 24, 21, and 20 days (P = 0.001). The most important variables related to ES were HCT-CI >2 (p < 0.0001; HR 8.5) and risk groups (p < 0.0001; HR 7.2). Hence, G-CSF avoidance and corticosteroid's prophylaxis decrease morbidity in patients undergoing PBSCT with MM treated with bortezomib/IMiDs.

The evolution of T-cell depletion in haploidentical stem-cell transplantation

T-cell depletion (TCD) can prevent the onset of graft-versus-host disease (GvHD) in animal models of bone marrow transplantation; this manipulation enabled the successful application in the 1980s of T-cell depleted bone marrow (BM) for the treatment of babies with severe combined immune deficiency (SCID). However, in leukaemia patients, implementation of T-cell depletion has been more difficult, especially due to high rate of graft-rejection, leukaemia relapse and delayed immune reconstitution. These hurdles were gradually overcome by modifying the cell composition of the graft, and by reducing the toxicities associated with conditioning protocols. Although no 'gold standard' TCD method exists, T-cell depletion in its modern forms could offer clinical benefit, even for patients with a matched sibling donor.

Autologous hematopoietic stem cell transplantation in autoimmune diseases

The term 'autoimmune diseases' encompasses a spectrum of diseases whose clinical manifestations and, possibly, biological features vary widely. The results of conventional treatment are considered unsatisfactory in aggressive forms, with subsets of patients having short life expectancies. Relying on wide experimental evidence and more feeble clinical data, some research groups have used autologous hematopoietic stem cell transplantation (HSCT) in the most disabling autoimmune diseases with the aim of resetting the patient's immune system. Immunoablative conditioning regimens are preferred over their myeloablative counterparts, and some form of in vivo and/or ex vivo T-cell depletion is generally adopted. Despite 15 years' experience, published controlled clinical trials are still lacking, with the evidence so far available coming from pilot studies and registry surveys. In multiple sclerosis, clinical improvement, or at least lasting disease stabilization, can be achieved in the majority of the patients; nevertheless, the worst results are observed in patients with progressive disease, where no benefit can be expected from conventional therapy. Concerning rheumatologic diseases, wide experience has been acquired in systemic sclerosis, with long-term improvements in cutaneous disease being frequently reported, although visceral involvement remains unchanged at best. Autografting has proved to be barely effective in rheumatoid arthritis and quite toxic in juvenile idiopathic arthritis, whereas it leads to clinical remission and the reversal of visceral impairment in the majority of patients with systemic lupus erythematosus. A promising indication is Crohn's disease, in which long-term endoscopic remission is frequently observed. Growing experience with autologous HCST in autoimmune diseases has progressively reduced concerns about transplant-related mortality and secondary myelodysplasia/leukemia. Therefore, a sustained complete remission seems to be within the reach of autografting in some autoimmune diseases; in others, the indications, risks and benefits of autografting need to be better defined. Consequently, the search for new drugs should also be encouraged.

Total parenteral nutrition associated with severe insulin resistance following hematopoietic stem cell transplantation in patients with hemophagocytic syndrome: report on two cases

Hyperglycemia secondary to total parenteral nutrition (TPN) is reported in adults. In addition, insulin resistance and type 2 diabetes as late consequences of hematopoietic stem cell transplantation (HSCT) are well described. Both situations are generally manageable with traditional insulin dosing. We present two children who developed severe insulin resistance requiring intravenous insulin therapy at doses up to 13 units/kg/h. Both children were on TPN after undergoing HSCT for hemophagocytic syndrome. We believe that our report will alert physicians to such a condition and help with early recognition that is a key to successful intervention. These cases aim to increase awareness and stimulate research to unravel the associated underling mechanisms.

Stem cell transplantation in Multiple Sclerosis: Safety and Ethics

Stem cell therapy is considered a promising strategy aiming at neuronal and glial cell replacement or neuroprotection in neurological diseases affecting the brain and spinal cord. Multiple Sclerosis (MS), characterized by inflammation-induced destruction of the myelin sheath surrounding axons leading to conduction deficits and variability of clinical signs, is not an exception. MS is considered an autoimmune disease and, in the last few years, an intense immunodepletion followed by autologous hematopoietic-stem-cell transplant (HSCT) is being assessed as potential therapeutical strategy for severe patients unresponsive to the immunomodulatory and immunosuppressive treatment. Partially supported by evidence in animal models and by anecdotal reports on the beneficial effects on MS patients with concomitant malignant diseases, HSCT programs for MS have been initiated worldwide and follow-up data are accumulating. A Consensus Meeting has been held in Milano (1998) providing a document that defined criteria for patient selection, transplantation procedures, and outcome evaluations. Nowadays the high number of patients already treated allows us to draw initial conclusions related to clinical efficacy. After careful monitoring of the available data and improvement of the procedure, safety seems not to be anymore an issue. Ethics of HSCT deserve, on the contrary, a profound evaluation: the procedure is a multistep process with manifold options, each step with different ethical implications. Even more difficult appears the definition of the MS patient selection criteria for HSCT. The informed consensus needs to be exhaustive for the full comprehension of a complex procedure. In conclusion, although HCST is today an established therapeutical option for MS patients, safety and ethical issues need to be further clarified.

Allogeneic bone marrow transplantation in models of experimental autoimmune encephalomyelitis: evidence for a graft-versus-autoimmunity effect

Autologous hematopoietic stem cell transplantation (HSCT) is being explored in the treatment of severe multiple sclerosis (MS), and is based on the concept of "resetting" the immune system. The use of allogeneic HSCT may offer additional advantages, such as the replacement of the autoreactive immune compartment by healthy allogeneic cells and development of a graft-versus-autoimmunity (GVA) effect. However, in clinical practice, the genetic susceptibility to MS of allogeneic stem cell donors is generally unknown, and GVA may therefore be an important mechanism of action. Experimental autoimmune encephalomyelitis (EAE)-susceptible and -resistant mouse strains were used to determine the roles of genetic susceptibility, level of donor-chimerism, and alloreactivity in the therapeutic potential of syngeneic versus allogeneic bone marrow transplant (BMT) for EAE. After transplantation and EAE induction, animals were evaluated for clinical EAE and ex vivo myelin oligodendrocyte glycoprotein-specific proliferation. Early after BMT, both syngeneic and allogeneic chimeras were protected from EAE development. On the longer term, allogeneic but not syngeneic BMT conferred protection, but this required high-level donor-chimerism from EAE-resistant donors. Importantly, when EAE-susceptible donors were used, robust protection from EAE was obtained when active alloreactivity, induced by donor lymphocyte infusions, was provided. Our findings indicate the requirement of a sufficient level of donor-chimerism from a nonsusceptible donor in the therapeutic effect of allogeneic BMT. Importantly, the data indicate that, independently of genetic susceptibility, active alloreactivity is associated with a GVA effect, thereby providing new evidence to support the potential role of allogeneic BMT in the treatment of MS.

Autologous peripheral blood stem cell transplantation for severe multiple sclerosis

We describe the results of a clinical trial to evaluate the feasibility and toxicity of autologous hematopoietic stem cell transplantation (auto-HSCT) for patients with progressive multiple sclerosis (MS). Fifteen patients (all patients with secondary progressive MS) were enrolled. The median expanded disability status scale (EDSS) score at baseline was 6.0 (range, 4.5-7.5). Peripheral blood stem cells were obtained by leukapheresis after mobilization with granulocyte colony-stimulating factor. In 9 patients, CD34+ cell selection was performed with a CliniMACS cell selection system, and 6 patients accepted infusion of unmodified peripheral blood stem cells. The modified BEAM (carmustine, teniposide, cytarabine, and melphalan) was the sole conditioning regimen used. The adverse effects included infections, mucositis, transient hepatotoxicity, and diarrhea. Three patients had flares of neurologic deterioration during mobilization, 8 patients had the same manifestation during transplantation, and 2 patients had similar flares within 3 months of transplantation. Six patients experienced continuous neurologic improvement after transplantation, 5 patients experienced neurologic progression, and 4 patients had stabilization of their disease. The confirmed progression-free rate was 63.8% at 49 months. The results of lymphocyte purging were no better than for no purging. Auto-HSCT proved to be safe and beneficial for some MS patients. Further studies are needed to establish the merit of this procedure for MS patients.

Co-receptor and co-stimulation blockade for mixed chimerism and tolerance without myelosuppressive conditioning

BACKGROUND

A major challenge in the application of marrow transplantation as a route to immunological tolerance of a transplanted organ is to achieve hematopoietic stem cell (HSC) engraftment with minimal myelosuppressive treatments.

RESULTS

We here describe a combined antibody protocol which can achieve long-term engraftment with clinically relevant doses of MHC-mismatched bone marrow, without the need for myelosuppressive drugs. Although not universally applicable in all strains, we achieved reliable engraftment in permissive strains with a two-stage strategy: involving first, treatment with anti-CD8 and anti-CD4 in advance of transplantation; and second, treatment with antibodies targeting CD4, CD8 and CD40L (CD154) at the time of marrow transplantation. Long-term mixed chimerism through co-receptor and co-stimulation blockade facilitated tolerance to donor-type skin grafts, without any evidence of donor-antigen driven regulatory T cells.

CONCLUSION

We conclude that antibodies targeting co-receptor and co-stimulatory molecules synergise to enable mixed hematopoietic chimerism and central tolerance, showing that neither cytoreductive conditioning nor 'megadoses' of donor bone marrow are required for donor HSC to engraft in permissive strains.

T-lymphocyte reconstitution following rigorously T-cell-depleted versus unmodified autologous stem cell transplants

We compared the kinetics of T-cell recovery after extensive ex vivo and in vivo T-cell depleted autologous stem cell transplantation (SCT) for multiple sclerosis (MS; n=8) with unmodified SCT for hematological malignancies (HM; n=39). Both patient group showed a very protracted recovery of 'naive' CD4(+), 45R0(-) ( approximately CD45RA(+)) T-cells. Within the 'primed' CD4(+), 45R0(+) T-cells, the 'central memory' cells expressing the CD62L and CD27 markers were the slowest to recover. The repopulating T-cells were highly activated, as shown by increased expression of HLA-DR and the apoptosis marker CD95. The capability of CD4(+) and CD8(+) T-cells to produce IFN-gamma, IL-2 and TNF-alpha had reached normal ranges from 2 months post SCT onwards. Unexpectedly, the kinetics of T-cell recovery between 3 and 12 months post transplant was similar in T-depleted and unmodified SCT. Before SCT, the HM patients showed lymphopenia of all T-cell subsets, upregulated HLA-DR and CD95 expression and increased cytokine responses. We suggest that the similar kinetics of T-cell recovery in the two patient groups may be explained by the susceptibility to apoptosis of the activated CD4(+) T-cells in the autografts of the HM patients. This susceptibility to apoptosis would interfere with a swift and sustained CD4(+) T-cell regeneration post SCT.

A phase I-II trial of autologous peripheral blood stem cell transplantation in the treatment of refractory autoimmune disease

OBJECTIVES

To carry out a phase I-II trial to elucidate the feasibility and efficacy of high dose cyclophosphamide (CY) supported by autologous peripheral blood stem cell transplantation (PBSCT) in the treatment of severe and refractory autoimmune disease (AD).

METHODS

Peripheral blood stem cells (PBSCs) were mobilised during haematological recovery after relatively high dose CY (2 g/m2) for 2 days, followed by administration of granulocyte colony stimulating factor. After collecting PBSCs--more than 2x10(6) CD34+ cells/kg--by apheresis, CD34+ cells were immunologically selected and cryopreserved. Eight patients were enrolled--five had systemic sclerosis (SSc) alone, one had SSc with systemic lupus erythematosus, one amyopathic dermatomyositis (ADM), and one Wegener's granulomatosis (WG). All of the patients were treated with high dose CY (50 mg/kg) for 4 days and autologous PBSCT.

RESULTS

Haematopoietic reconstitution was rapid and sustained. Toxicity due to the regimen included various infections such as pneumonia, sepsis, cystitis, herpes zoster, and acute heart failure. However, there was no treatment related mortality. Encouraging results were obtained after autologous PBSCT. Sclerosis of the skin was markedly improved in all of the patients with SSc. Interstitial pneumonia (IP), evaluated by PaO2, serum KL-6 levels, and pulmonary high resolution computed tomography, improved significantly. In a patient with ADM, severe and progressive IP also improved markedly. In a patient with WG, the size of the left orbital granuloma decreased substantially, resulting in reduction of the exophthalmos.

CONCLUSIONS

These observations suggest that high dose CY with autologous PBSCT is feasible and may be effective in the treatment of severe and refractory AD.

Successful treatment of rapidly progressive interstitial pneumonia with autologous peripheral blood stem cell transplantation in a patient with dermatomyositis

Aggressive autoimmune diseases are often treated by intensive immunosuppressive treatment such as high-dose methylprednisolone and intravenous cyclophosphamide. Autologous hematopoietic stem cell transplantation can facilitate high-dose immunosuppressive therapy (HDIT), which is myeloablative. We describe a 54-year-old female patient with rapidly progressive and refractory interstitial pneumonia due to dermatomyositis, which was successfully treated with high-dose cyclophosphamide and autologous blood stem cell transplantation. Following transplantation, dyspnea disappeared, and arterial blood gas analysis and respiratory function test showed marked improvement. This improvement was confirmed by diminished interstitial shadows on chest X-ray and computed tomography scans. Eighteen months after transplantation, the patient is doing well without symptoms and signs of interstitial pneumonia.

Induction of tolerance to self-antigens using genetically modified bone marrow cells

The challenge of finding a lasting cure for autoimmune disease(s) has not been met. Although the use of systemic anti-inflammatory agents still dominates the treatment of these diseases, there is a push towards developing novel and more specific strategies. In addressing autoimmunity, there is the intrinsic need to understand the mechanisms that lead to the development and maintenance of immunological tolerance to self-antigens. Experimental evidence has shown that directed antigen expression in the thymus can induce immunological tolerance to that antigen. This forms the cornerstone of one strategy directed towards the cure of autoimmunity. In this strategy, individuals with autoimmune disease are transplanted with bone marrow stem cells that have been genetically modified and in this way allow expression of the self-antigen in the thymus.

Evans' syndrome following autologous peripheral blood stem cell transplantation for non-Hodgkin's lymphoma

A 34-year-old woman with non-Hodgkin's lymphoma received high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT). She developed Evans' syndrome, the association of immune thrombocytopenia and autoimmune hemolytic anemia, 49 days after transplantation. Multiple autoimmune disorders may occur concurrently after autologous PBSCT.

Autologous haematopoietic-stem-cell transplantation for multiple sclerosis

Intense immunosuppression followed by autologous haematopoietic-stem-cell transplantation (HSCT) is being assessed as a potential treatment for patients with severe multiple sclerosis (MS). The treatment was developed from research that showed autologous HSCT was as effective as allogeneic HSCT in the treatment of experimental autoimmune encephalomyelitis. The treatment is thought to eradicate the defective immune system, and the infused haematopoietic stem cells reconstitute an immune system that is more tolerant to the nervous system. About 250 patients with MS have been treated with autologous HSCT as part of phase I and phase II open trials. Autologous HSCT seems feasible in MS and assessment with clinical and MRI measures suggests it induces a profound and long-lasting suppression of inflammation. The course of MS seems to be stabilised after autologous HSCT, especially in ambulatory patients with evidence of active disease. Autologous HSCT deserves further study in randomised controlled trials.

Steroids prevent engraftment syndrome after autologous hematopoietic stem cell transplantation without increasing the risk of infection

Engraftment syndrome (ES) following autologous hematopoietic stem cell transplantation (AHSCT) is characterized by fever and rash. In January 2002, we instituted steroid prophylaxis for ES from day +4 to +14. This study was conducted to assess whether this practice increased the risk of infection. In total, 194 consecutive patients were reviewed, 111 did not receive steroid prophylaxis (group A), and 83 did (group B). Initial antimicrobial prophylaxis was the same in both groups. There were no significant differences between groups in age, gender, race, prior radiation therapy, number of prior chemotherapy regimens, disease status at transplant, mobilization regimen, days of leukopheresis, CD34(+) cell dose, and days to platelet and neutrophil engraftment. Group B had significantly fewer patients with non-Hodgkin's lymphoma and multiple myeloma, shorter median duration from diagnosis to transplant, lower risk of ES, and shorter mean length of hospital stay. The incidence of early and late microbiologically confirmed infections was not significantly different between groups. Types of infections and types of organisms identified were similar in both groups. Hospital readmission rates were similar in both groups. Steroid prophylaxis significantly decreases the risk of ES following AHSCT, and is associated with shortened hospitalization, without increasing risk of infection.

Autologous hematopoietic stem cell transplantation for refractory antiphospholipid syndrome causing myocardial necrosis

Autologous hematopoietic stem cell transplantation (HSCT) is currently being evaluated as a treatment for autoimmune diseases, including systemic lupus erythematosus (SLE), that are associated with a very severe prognosis. We describe a 27-year-old woman with SLE with a 10-year history of refractory antiphospholipid syndrome (APS). She developed progressive myocardial necrosis despite treatment with corticosteroids, cyclophosphamide (CYC), cyclosporine, and immunopheresis. After conditioning with CYC, fludarabine, and antithymocyte globulin, autologous HSCT using CD34(+) selection was performed. After transplantation, the clinical symptoms caused by APS remitted, and the serum anticardiolipin antibody level decreased. Remission has persisted for 21 months after transplantation. Although a longer follow-up is required for the assessment of efficacy, autologous HSCT may cure patients with refractory APS.

High-dose immunosuppression with autologous stem cell transplantation in severe refractory systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an immune-mediated disease that is responsive to suppression or modulation of the immune system. Patients with SLE who experience persistent multiorgan dysfunction, despite standard doses of intravenous cyclophosphamide (Cy), represent a subset of patients at high risk of early death. We investigated the efficacy and toxicity of high-dose immunosuppression and autologous hematopoietic stem cell transplantation (SCT) to treat such patients. Six patients (all female, age 15-29 years) with severe refractory SLE were enrolled in the clinic of our institution from 1998 to 2003. All patients were seriously ill, with SLE disease activity indices (SLEDAI) of 6-30, including two cases with central nervous system lupus, one case with lung vasculitis, and three cases with nephritis and nephrotic syndrome. All patients were registered in the European Group for Blood and Marrow Transplantation (EBMT)/European League Against Rheumatism (EULAR) database. Previous immunosuppression included pulse Cy intravenous, prednisolone (standard doses and pulse therapy), oral Cy and azathioprine, with little or no effect on disease progression. Autologous hemopoietic stem cells were collected from bone marrow (n = 4) or mobilized from peripheral blood with Cy and granulocyte colony-stimulating factor (G-CSF) (n = 2). Pre-transplant conditioning regimens included BEAM +/- ATG (n = 2), melphalan 140 mg/m2 + etoposid 1600 mg/m2 (n = 2) and Cy 200 mg/kg +/- ATG (n = 2). Median time to an absolute neutrophil count (ANC) greater than 0.5 x 10(9)/L and platelet count greater than 50 x 10(9)/L was 13 and 15 days, respectively. Three patients died on days 11, 22 and 63 due to transplant-related complications. The follow-up is now 60 and six months for two patients (complete remission), and 42 months for one other patient (partial response). All patients had experienced multiple and severe episodes of infections pre-SCT and long-term history of corticosteroid therapy (3-14 years). We conclude that achievement of prolonged, corticosteroid-free remissions is a reality. Judicious selection of patients earlier in disease or in remission, but with a high risk of relapse or further progression, will diminish transplantation-related mortality.

High-dose immunosuppressive therapy and autologous peripheral blood stem cell transplantation for severe multiple sclerosis

There were 26 patients enrolled in a pilot study of high-dose immunosuppressive therapy (HDIT) for severe multiple sclerosis (MS). Median baseline expanded disability status scale (EDSS) was 7.0 (range, 5.0-8.0). HDIT consisted of total body irradiation, cyclophosphamide, and antithymocyte globulin (ATG) and was followed by transplantation of autologous, granulocyte colony-stimulating factor (G-CSF)-mobilized CD34-selected stem cells. Regimen-related toxicities were mild. Because of bladder dysfunction, there were 8 infectious events of the lower urinary tract. One patient died from Epstein-Barr virus (EBV)-related posttransplantation lymphoproliferative disorder (PTLD) associated with a change from horse-derived to rabbit-derived ATG in the HDIT regimen. An engraftment syndrome characterized by noninfectious fever with or without rash developed in 13 of the first 18 patients and was associated in some cases with transient worsening of neurologic symptoms. There were 2 significant adverse neurologic events that occurred, including a flare of MS during mobilization and an episode of irreversible neurologic deterioration after HDIT associated with fever. With a median follow-up of 24 (range, 3-36) months, the Kaplan-Meier estimate of progression (>/= 1.0 point EDSS) at 3 years was 27%. Of 12 patients who had oligoclonal bands in the cerebrospinal fluid at baseline, 9 had persistence after HDIT. After HDIT, 4 patients developed new enhancing lesions on magnetic resonance imaging of the brain. The estimate of survival at 3 years was 91%. Important clinical issues in the use of HDIT and stem cell transplantation for MS were identified; however, modifications of the initial approaches appear to reduce treatment risks. This was a heterogeneous high-risk group, and a phase 3 study is planned to fully assess efficacy.

Hematopoietic chimerism and central tolerance created by peripheral-tolerance induction without myeloablative conditioning

Allogeneic hematopoietic chimerism leading to central tolerance has significant therapeutic potential. Realization of that potential has been impeded by the need for myeloablative conditioning of the host and development of graft-versus-host disease (GVHD). To surmount these impediments, we have adapted a costimulation blockade-based protocol developed for solid organ transplantation for use in stem cell transplantation. The protocol combines donor-specific transfusion (DST) with anti-CD154 mAb. When applied to stem cell transplantation, administration of DST, anti-CD154 mAb, and allogeneic bone marrow leads to hematopoietic chimerism and central tolerance with no myeloablation and no GVHD. Tolerance in this system results from deletion of both peripheral host alloreactive CD8+ T cells and nascent intrathymic alloreactive CD8+ T cells. In the absence of large numbers of host alloreactive CD8+ T cells, the transfusion that precedes transplantation need not be of donor origin, suggesting that both allospecific and non-allospecific mechanisms regulate engraftment. Agents that interfere with peripheral transplantation tolerance impair establishment of chimerism. We conclude that robust allogeneic hematopoietic chimerism and central tolerance can be established in the absence of host myeloablative conditioning using a peripheral transplantation tolerance protocol.

Intense immunosuppression and stem-cell transplantation for patients with severe rheumatic autoimmune disease: a review

BACKGROUND

Intense immunosuppression plus stem-cell transplantation (SCT) has emerged as a new treatment modality for patients with refractory, severe rheumatic autoimmune disease. Its rationale is based on eliminating autoaggressive lymphocytes by lympho- or myeloablative conditioning followed by stem-cell rescue. Preclinical studies in animal models of autoimmune disease and observations in patients with rheumatoid arthritis (RA) who were cured after allogeneic bone marrow transplantation for concomitant hematologic malignancy have provided support for the concept.

METHODS

The authors reviewed the results of recent phase I/II studies and data from the EBMT/EULAR Registry on more than 400 patients with autoimmune diseases including RA, systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and juvenile idiopathic arthritis (JIA).

RESULTS

Toxicity resulting from stem-cell grafting depended on underlying disease and the intensity of the conditioning regimen. Treatment-related mortality was low in RA (1.4%) but relatively high (>10%) in patients with JIA, SLE, and SSc, possibly related to visceral involvement in these patients. With the application of uniform and strict criteria, safety has improved. Long-term remissions up to 4 years have been observed in SSc and JIA, while relatively more relapses have occurred in patients with SLE and RA. Sensitivity to antirheumatic drugs was restored in RA and SLE patients, however, resulting in improved disease control.

CONCLUSIONS

Intense immunosuppression and SCT may be an effective therapy for selected patients with severe rheumatic autoimmune disease. Its merits need to be proven via multicenter phase III studies by comparing efficacy and safety with conventional therapy.

Hematopoietic Cell Transplantation for Benign Hematological Disorders and Solid Tumors

Allogeneic hematopoietic cell transplantation (HCT) has been successfully used as replacement therapy for patients with aplastic anemia and hemoglobinopathies. Both autologous and allogeneic HCT following high-dose chemotherapy can correct manifestations of autoimmune diseases. The impressive allogeneic graft-versus-tumor effects seen in patients given HCT for hematological malignancies have stimulated trials of allogeneic immunotherapy in patients with otherwise refractory metastatic solid tumors. This session will update the status of HCT in the treatment of benign hematological diseases and solid tumors.

In Section I, Dr. Rainer Storb reviews the development of nonmyeloablative conditioning for patients with severe aplastic anemia who have HLA-matched family members. He also describes the results in patients with aplastic anemia given HCT from unrelated donors after failure of responding to immunosuppressive therapy. The importance of leuko-poor and in vitro irradiated blood product transfusions for avoiding graft rejection will be discussed.

In Section II, Dr. Guido Lucarelli reviews the status of marrow transplantation for thalassemia major and updates results obtained in children with class I and class II severity of thalassemia. He also describes results of new protocols for class III patients and efforts to extend HCT to thalassemic patients without HLA-matched family members.

In Section III, Dr. Peter McSweeney reviews the current status of HCT for severe autoimmune diseases. He summarizes the results of autologous HCT for systemic sclerosis, multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematosus, and reviews the status of planned Phase III studies for autologous HCT for these diseases in North America and Europe. He also discusses a possible role of allogeneic HCT in the treatment of these diseases.

In Section IV, Dr. Richard Childs discusses the development and application of nonmyeloablative HCT as allogeneic immunotherapy for treatment-refractory solid tumors. He reviews the results of pilot clinical trials demonstrating graft-versus-solid tumor effects in a variety of metastatic cancers and describes efforts to characterize the immune cell populations mediating these effects, as well as newer methods to target the donor immune system to the tumor.

Hematopoietic Cell Transplantation for Benign Hematological Disorders and Solid Tumors

Allogeneic hematopoietic cell transplantation (HCT) has been successfully used as replacement therapy for patients with aplastic anemia and hemoglobinopathies. Both autologous and allogeneic HCT following high-dose chemotherapy can correct manifestations of autoimmune diseases. The impressive allogeneic graft-versus-tumor effects seen in patients given HCT for hematological malignancies have stimulated trials of allogeneic immunotherapy in patients with otherwise refractory metastatic solid tumors. This session will update the status of HCT in the treatment of benign hematological diseases and solid tumors.

In Section I, Dr. Rainer Storb reviews the development of nonmyeloablative conditioning for patients with severe aplastic anemia who have HLA-matched family members. He also describes the results in patients with aplastic anemia given HCT from unrelated donors after failure of responding to immunosuppressive therapy. The importance of leuko-poor and in vitro irradiated blood product transfusions for avoiding graft rejection will be discussed.

In Section II, Dr. Guido Lucarelli reviews the status of marrow transplantation for thalassemia major and updates results obtained in children with class I and class II severity of thalassemia. He also describes results of new protocols for class III patients and efforts to extend HCT to thalassemic patients without HLA-matched family members.

In Section III, Dr. Peter McSweeney reviews the current status of HCT for severe autoimmune diseases. He summarizes the results of autologous HCT for systemic sclerosis, multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematosus, and reviews the status of planned Phase III studies for autologous HCT for these diseases in North America and Europe. He also discusses a possible role of allogeneic HCT in the treatment of these diseases.

In Section IV, Dr. Richard Childs discusses the development and application of nonmyeloablative HCT as allogeneic immunotherapy for treatment-refractory solid tumors. He reviews the results of pilot clinical trials demonstrating graft-versus-solid tumor effects in a variety of metastatic cancers and describes efforts to characterize the immune cell populations mediating these effects, as well as newer methods to target the donor immune system to the tumor.