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Although most patients who have cutaneous T-cell lymphoma have an indolent clinical course, patients who have cutaneous tumors, lymph node or visceral involvement, or peripheral blood involvement generally have rapidly progressive disease with shorter survival. In those patients with poor prognostic features, conventional combination chemotherapy is usually ineffective. High-dose chemotherapy with autologous hematopoietic stem cell transplant (HSCT) results in high remission rates, but the recurrence is inevitable and rapid. Allogeneic HSCT, in contrast, provides durable long-term remissions and is currently the only potentially curative therapy.

Objective: Donor lymphocytes mediate both a beneficial graft-vs-leukemia/lymphoma (GVL) effect as well as graft-vs-host disease (GVHD), the most dreaded complication of allogeneic hematopoietic stem cell transplantation (HSCT). Transduction of donor lymphocytes with a herpes simplex thymidine kinase (HSVtk) gene prior to infusion confers lethal sensitivity to the anti-herpes drug, ganciclovir (GCV). HSVtk-transduced donor lymphocyte infusions (DLI) have already been used and significant problems have limited the clinical experience to very few patients. To this end, we also report on a study of whether HSVtk-DLI induces GVHD/GVL and if infusion of GCV allows abrogation of GVHD by selective killing of donor lymphocytes., Materials and Methods: Nine patients with relapsed hematologic malignancies after allogeneic hematopoietic stem cell transplantation (HSCT) were infused with HSVtk gene-modified donor lymphocytes. In brief, transgeneic lymphocytes were prepared by 3 days of activation, 1 day of transduction, 6 days of selection with G418, and 2 to 4 weeks of expansion., Results: From 5.0 to 199 x 10(6) CD3(+) DLI were infused. There were no toxicities and no correlation between CD3(+) cell dose and either GVHD or GVL was observed. Only one patient who had cutaneous T-cell lymphoma (CTCL) developed GVHD and that same patient is the only patient to have an anti-tumor response. The patient was infused with 23 x 10(6) CD4(+) and 9.7 x 10(6) CD8(+) HSVtk DLI. Following discontinuation of immune suppression and infusion of GCV, GVHD promptly resolved. Although the CTCL relapsed, it has been easily controlled with intermittent topical therapy. One patient with acute myelogenous leukemia (AML) had a remission inversion of undetermined significance. Two patients with AML, one patient with lymphoma, and four patients with chronic myelogenous leukemia (CML) did not respond., Conclusion: HSVtk-DLI may provide an anti-tumor effect in vivo and may induce GVHD that is abrogated by GCV treatment. While technical aspects to improve response need to be perfected, HSVtk-DLI infusion to induce a transient GVL/GVHD may become an effective future therapy to minimize complications of allogeneic HSCT.

There were 21 patients with rapidly progressive multiple sclerosis (MS) treated on a phase 1/2 study of intense immune suppressive therapy and autologous hematopoietic stem cell (HSC) support with no 1-year mortality. Following transplantation, one patient had a confirmed acute attack of MS. Neurologic progression defined by the expanded disability status scale (EDSS) did not increase in disability by 1.0 or more steps in any of 9 patients with a pretransplantation EDSS of 6.0 or less. In 8 of 12 patients with high pretransplantation disability scores (EDSS > 6.0), progressive neurologic disability as defined by at least a 1-point increase in the EDSS has occurred and was manifested as gradual neurologic deterioration. There were 2 patients with a pretransplantation EDSS of 7.0 and 8.0 who died from complications of progressive disease at 13 and 18 months following treatment. Our experience suggests that intense immune suppression using a total body irradiation (TBI)-based regimen and hematopoietic stem cell transplantation (HSCT) are not effective for patients with progressive disease and high pretransplantation disability scores. Further studies are necessary to determine the role of intense immune suppressive therapy and HSC support in ambulatory patients with less accumulated disability and more inflammatory disease activity. Specifically, more patients and longer follow-up would be required in patients with an EDSS of 6.0 or less before drawing conclusions on this subgroup.

Hematopoietic stem cell transplantation of multiple sclerosis is rapidly expanding. Success for this approach requires an understanding of the pathophysiology of multiple sclerosis and design of trials that select patients with active inflammatory disease, low disability scores, and avoidance of conditioning agents that may damage neural stem cell compartments or further compromise already injured axons.

Hematopoietic stem cell transplantation as a treatment for autoimmune disease began in 1996 and has subsequently spread worldwide. In Europe phase III trials have opened, while in America phase III trials are being designed and funded by the National Institutes of Health. On 6 June 2002, clinicians and scientists from around the world met at Snowbird, Utah to discuss the results and future directions of stem cell therapy for autoimmune diseases. What follows are general concepts from chairpersons of this meeting.

At Northwestern University, a phase I/II trial of hematopoietic stem cell transplant (HSCT) for systemic lupus erythematosus (SLE) has shown promising results. A phase III HSCT trial is being developed to confirm efficacy of HSCT vs continuing the currently accepted standard of care, intravenous pulse cyclophosphamide.

Systemic sclerosis (SSc) is presumed to be an immune-mediated vasculopathy of unknown etiology. SSc is unresponsive to most immune-modulating therapies except for intravenous cyclophosphamide, which is reported to demonstrate some benefit. We, therefore, dose-escalated cyclophosphamide to 200 mg/kg and added rabbit ATG 7.5 mg/kg along with infusion of unselected hematopoietic stem cells to minimize the cytopenic interval. Engraftment occurred rapidly (day 8) with minimal unexpected toxicity, no infections, and unexpectedly rapid improvement in the modified Rodnan Skin Score.

Hematopoietic stem cell transplantation (HSCT) for autoimmune diseases have been, because of safety reasons, overwhelmingly autologous. Results are, in general, encouraging with improvement in quality of life, a remission of up to several years, and perhaps in some diseases improved survival. This indicates that further study of autologous HSCT especially under phase III design is warranted. However, the ultimate goal of HSCT is cure of otherwise incurable autoimmune diseases. For this reason, allogeneic HSCT in carefully selected high-risk patients with autoimmune diseases using strategies to minimize both regimen-related toxicity and graft-versus-host disease (GVHD) is ongoing at Northwestern University and will be reviewed briefly.

It is clear that some patients with severe Crohn's disease (CD) fail to respond favorably to the standard treatment, including antibody to Tumor Necrosis Factor alpha (TNFalpha), We have embarked on a unique therapy for this group of patients, intense immune suppression followed by autologous hematopoietic stem cell transplantation (HSCT). The response to this approach in our first four patients has been excellent, with there being no significant untoward event from the transplantation and with each patient entering clinical remission in terms of the Crohn's Disease Activity Index off all therapy for CD and no diarrhea or abdominal pain. However, some evidence of minor laboratory abnormalities and slight inflammation of the colon on colonoscopic evaluation persist up to 1 year post-transplant. It is suggested that HSCT should be considered a reasonable option for patients who have failed standard CD therapy, although long-term follow-up will be necessary to confirm the duration of the induced clinical remission.

Transduction of stem cells with a marking gene holds promise to determine if tissue repair or regeneration is derived from the adult hematopoietic stem cell and if relapse of an autoimmune disease should occur whether relapse arises from the stem cell compartment or from lymphocytes surviving the conditioning regimen. New safety concerns about gene-modified stem cell would entail new safety testing such as documentation of the insertional site prior to release.

Hematopoietic stem cell transplantation (HSCT) is being increasingly utilized for the treatment of a whole spectrum of severe autoimmune diseases refractory to conventional therapy. Although allogeneic HSCT has been followed by durable complete remission in a restricted number of patients with coincidental disease, the autologous procedure is generally preferred because of its lesser toxicity. Most autoimmune diseases are the consequence of a multistep process, mainly originating from the interplay of genetic, environmental, and hormonal factors. It has been postulated that if immunosuppressive regimens can eliminate or effectively reduce the level of autoreactive T and B cells, then regeneration of de novo immunity even in the autologous setting may bypass the initial breakdown of self-tolerance and ensure prolonged disease remission. As mentioned in a recent review of this field, protocol design including conditioning regimen, patient selection, stem cell source and final outcome are likely to be disease-specific. The following is a summary of the 2002 International Bone Marrow Transplantation Registry/American Society of Blood and Bone Marrow Transplantation (IBMTR/ASBMT) satellite symposium in Orlando, Florida on 24 February 2002 on 'Expanding the Promise of Hematopoietic Stem Cell Transplantation in Autoimmune Diseases'.

Two patients with severe Crohn disease, defined by a Crohn Disease Activity Index (CDAI) higher than 250 despite anti-tumor necrosis factor alpha (TNF-alpha), were treated by intense immune suppression and autologous hematopoietic stem cell transplantation (HSCT). Stem cells were mobilized from the peripheral blood using cyclophosphamide (2.0 g/m2) and granulocyte colony-stimulating factor (G-CSF; 5 micro g/kg/d), enriched ex vivo by CD34+ selection, and reinfused after immune conditioning with cyclophosphamide (200 mg/kg) and equine anti-thymocyte globulin (ATG; 90 mg/kg). Patients have remained in remission (CDAI < 100) for 1 year since HSCT. We conclude that further HSCT studies for severe Crohn disease appear warranted.

Hematopoietic stem cell transplantation was first reported for patients with systemic lupus erythematosus in 1997. The procedure has since been performed worldwide including in Europe, in Brazil, and in China. A National Institutes of Health-funded phase III clinical trial of hematopoietic stem cell transplantation for refractory systemic lupus erythematosus is anticipated to begin in 2003. Encouraging responses are raising new hope about the role of adult hematopoietic stem cells in systemic lupus erythematosus.

Hematopoietic stem cells (HSCs) are the earliest cells of the immune system, giving rise to B and T lymphocytes, monocytes, tissue macrophages, and dendritic cells. In animal models, adoptive transfer of HSCs, depending on circumstances, may cause, prevent, or cure autoimmune diseases. Clinical trials have reported early remission of otherwise refractory autoimmune disorders after either autologous or allogeneic hematopoietic stem cell transplantation (HSCT). By percentage of transplantations performed, autoimmune diseases are the most rapidly expanding indication for stem cell transplantation. Although numerous editorials or commentaries have been previously published, no prior review has focused on the immunology of transplantation tolerance or development of phase 3 autoimmune HSCT trials. Results from current trials suggest that mobilization of HSCs, conditioning regimen, eligibility and exclusion criteria, toxicity, outcome, source of stem cells, and posttransplantation follow-up need to be disease specific. HSCT-induced remission of an autoimmune disease allows for a prospective analysis of events involved in immune tolerance not available in cross-sectional studies.

Diabetes is a chronic disease with significant morbidity and mortality. Pancreas or islet cell transplantation is limited by a shortage of donors and chronic immune suppression to prevent allograft rejection. Consequently, interest exists in islet cell neogenesis from embryonic or mesenchymal stem cell as a possible cure for diabetes. However, unless tolerance to islet cells is re-established, diabetes treated by islet cell transplantation would remain a chronic disease secondary to immune suppression related morbidity. If islet cell tolerance could be re-induced, a major clinical hurdle to curing diabetes by islet cell neogenesis may be overcome. Recent studies suggest that adult hematopoietic stem cells (HSC) can reintroduce tolerance to auto-antigens. It is possible that HSC may also be able to switch lineage and, therefore, be a convenient source of stem cells for both inducing tolerance and islet cell regeneration.

There is little information about the clinical course of patients with rheumatoid arthritis (RA) who relapse after autologous blood stem cell transplantation (ASCT). We describe 6 patients with severe RA who received ASCT in 3 US centers. Duration of followup was between 24 and 42 months posttransplant. Five patients achieved major responses but relapsed 3-22 months posttransplant. Two patients with relapse improved remarkably after restarting disease modifying antirheumatic drugs (DMARD). Two patients developed a mild RA flare at 3 and 5 months posttransplant and improved spontaneously. All 4 patients who improved after an initial disease flare remained highly functional at 14-22 months posttransplant. All patients in this study were anti-tumor necrosis factor (TNF) drug naive; all received a TNF blocker as a second line posttransplant salvage therapy, but only 3 responded. Future ASCT strategies need to focus on improving the durability of the early posttransplant responses.

Patients with coincidental rheumatoid arthritis (RA) treated by allogeneic hematopoietic stem cell transplantation (HSCT) for drug induced aplastic anemia have been fortuitously cured of RA. Other than these examples with allogeneic HSCT, there is no known curative therapy for RA. Despite its potential to cure, allogeneic transplantation is not being offered to patients with RA due to transplant related mortality. Advances in HSCT conditioning regimens and better prevention of graft-versus-host disease should allow consideration of allogeneic HSCT as therapy for severe RA. We propose a new, well tolerated, nonmyeloablative allogeneic stem cell transplant regimen as treatment for RA.

In phase I (safety) trials, we have demonstrated the feasibility of autologous hematopoietic stem cell transplantation (HSCT) for patients with autoimmune diseases. Although this review comments on results of our phase I trials, the focus is on phase II (efficacy) trials using gene-marked autologous stem cells.

The treatment of severe autoimmune diseases has been recently revitalized by the introduction of intense immune suppression with immune ablative intent followed by three different procedures. These are allogeneic hematopoietic stem cell transplantation (HSCT), autologous HSCT (using either marrow or peripheral blood), and intense immune suppression without stem cell support. Current trials suggest that high dose immune suppressive therapy with or without autologous hematopoietic stem cell support can induce remission of previously refractory disease. Follow-up is too brief to determine if intense immune suppression, and more specifically autologous HSCT, will ultimately cure SLE. It is conceivable that an allogeneic source of stem cells from a normal donor (e.g. HLA matched sibling) will be required to achieve a cure. It is also possible that autologous HSCT, even if not curative, may prolong the life of patients with otherwise high-risk features. In carefully selected patients, the potential benefits of this procedure may outweigh the risks.

Adoptive cellular therapy is developing as a supplement or alternative to chemotherapy and/or radiation for malignant disease. Our focus is two ongoing clinical studies with transgeneic (genetically altered) cellular therapy; one uses allogeneic (from another person) lymphocytes to treat leukemia, and the second uses xenogeneic (from another species) fibroblast cells genetically altered to contain a toxin-producing suicide gene to treat ovarian cancer. Allogeneic donor lymphocyte infusions (DLI) are known to induce remission of hematologic malignancies. However, the toxicity associated with DLI is related to graft-versus-host-disease, which is due to donor lymphocytes attacking normal tissue in the recipient. Therefore, we have taken the approach of infusing DLI that have been modified to contain a latent suicide gene to treat leukemia. To treat ovarian cancer, we used xenogeneic nonimmune fibroblast-derived cells to deliver a tumor-directed cytotoxic gene to carcinoma cells. These cells release HStk transgene retroviruses that in turn transduce replicating tumor cells but not quiescent epithelium, rendering the tumor selectively susceptible to ganciclovir-mediated killing. These initial trials summarize the early stage of allogeneic/xenogeneic adoptive cellular therapy for cancer, and although the data are limited, it is encouraging to see some patients with evidence of antitumor responses. Advances in our understanding of the basic science of these treatments, together with improvements in the technology of vector design, will be required to streamline these methodologies into broader application.

Theiler's murine encephalomyelitis virus (TMEV) establishes a persistent infection in the central nervous system (CNS) leading to an inflammatory demyelinating disease of the CNS in which the histology and clinical course is similar to multiple sclerosis (MS). Disease pathogenesis is primarily due to T-cell-mediated destruction of myelin, which has been attributed to cytopathic effects of the virus, but immune-mediated destruction of myelin mediated via both virus-specific and myelin-specific T cells appear to play the major role. To determine if bone marrow transplantation would be an effective therapy for a virus-initiated autoimmune disease and to better separate viral cytopathic effects from immune-mediated demyelination, we ablated the immune system of TMEV-infected animals with 1,100 cGy total body irradiation, and then the animal's immunity was reconstituted by transplantation of disease-susceptible SJL/J mice with syngeneic marrow or disease-susceptible DBA/2J with marrow from disease-resistant (C57Bl/6 x DBA/2)F1 (B6D2) donors. Hematopoietic transplant performed after onset of disease resulted in 42% mortality in SJL/J syngeneic transplants, 47% mortality in diseased DBA2 recipients restored with marrow from naive B6D2 donors, and 12% in diseased DBA2 recipients receiving marrow from B6D2 donors previously infected with TMEV. Delayed type hypersensitivity (DTH) to both virion and myelin proteins was decreased in surviving mice that underwent transplantation; however, CNS viral titers were significantly elevated compared with nontransplanted controls. We conclude that a functional immune system with appropriate T-cell responses are important in prevention of lethal cytopathic CNS effects from TMEV. Relevant to the clinical use of bone marrow transplantation, attempts to ablate the immune system in viral-mediated immune diseases or virus-initiated autoimmune disease may have acute and lethal consequences. Our results raise concern about the attempted use of autologous hematopoietic transplantation in patients with MS, an autoimmune disease with a suspected virus etiology, particularly if the graft is aggressively depleted of lymphocytes.

Objective: For patients with systemic lupus erythematosus (SLE) who are at risk of disease-related mortality, we have initiated a protocol of intensive immunosuppression and haematopoietic stem cell support. The first patient enrolled in this study was in the midst of a lupus flare manifest by nephritis and rapidly declining renal function, uncontrolled hypertension, immune-mediated cytopenias, and serositis characterized by a large pericardial effusion and abdominal pain. Antinuclear antibody (ANA), anti-double-stranded (ds) DNA and complement were abnormal. This patient is now more than 1 yr post-stem cell transplant and is taking no immunosuppressive medication. Her serologies are normal, effusions have resolved, blood pressure is normal and renal function is markedly improved. The clinical and serological course of this patient is summarized here., Methods: Autologous haematopoietic stem cells (HSC) were mobilized with cyclophosphamide (2.0 g/m2) and granulocyte colony-stimulating factor (G-CSF) (10 microg/kg/day). Stem cells were enriched ex vivo using CD34-positive immunoselection and reinfused after immunosuppression with cyclophosphamide (200 mg/kg) and antithymocyte globulin (ATG) (90 mg/kg)., Results: White blood cell engraftment with an absolute neutrophil count (ANC) of >500/microl (0.5 x 10(9)/l) and platelet engraftment with a non-transfused platelet count of >20000/microl (20 x 10(9)/l) occurred on day 10 and 14, respectively. Therapy was complicated by a cell lysis-like effect with hyperphosphataemia, hyperuricaemia, normal anion gap metabolic acidosis and transient exacerbation of renal insufficiency., Conclusion: This is the first autologous T-cell-depleted haematopoietic stem cell transplantation performed to treat lupus in an active flare. This patient has, for the first time since discase onset (13 yr ago), entered a complete clinical and serological remission which persists at >1 yr of follow-up. The durability of this remission is unknown.

Many different stem cell subsets have been identified. Some of these subsets are multipotent, able to develop into any one of several cell types, while other stem cell subsets are committed to differentiated myeloid, lymphoid, erythroid, or megakaryocytic lineages.

The overall goal of adoptive immunotherapy with genetically modified lymphocytes is to decrease the morbidity and mortality associated with allogeneic bone marrow transplantation. The initial data reviewed here suggest that the behavior of the allogeneic HStk transgenic cells can be modified after administration to patients. Further study is needed to identify the response rates and risks associated with this procedure. In particular, larger studies will be needed with appropriate randomization to determine if the response rate to genetically modified cells is equivalent to the response rates with unmodified cells. Wider application of these techniques in the initial setting of allogeneic transplantation will undoubtedly occur and such trials have been initiated at several institutions. Careful attention to vector, suicide gene, selectable marker, efficiency of transduction, and cell dose will be necessary when comparing different trials since these variables will probably affect transgenic cell survival and response rates. [figure: see text]

Multiple sclerosis, systemic lupus erythematosus, and rheumatoid arthritis are immune-mediated diseases that are responsive to suppression or modulation of the immune system. For patients with severe disease, immunosuppression may be intensified to the point of myelosuppression or hematopoietic ablation. Hematopoiesis and immunity may then be rapidly reconstituted by reinfusion of CD34(+) progenitor cells. In 10 patients with these autoimmune diseases, autologous hematopoietic stem cells were collected from bone marrow or mobilized from peripheral blood with either granulocyte colony-stimulating factor (G-CSF) or cyclophosphamide and G-CSF. Stem cells were enriched ex vivo using CD34(+) selection and reinfused after either myelosuppressive conditioning with cyclophosphamide (200 mg/kg), methylprednisolone (4 g) and antithymocyte globulin (ATG; 90 mg/kg) or myeloablative conditioning with total body irradiation (1,200 cGy), methylprednisolone (4 g), and cyclophosphamide (120 mg/kg). Six patients with multiple sclerosis, 2 with systemic lupus erythematosus, and 2 with rheumatoid arthritis have undergone hematopoietic stem cell transplantation. Mean time to engraftment of an absolute neutrophil count greater than 500/microL (0.5 x 10(9)/L) and a nontransfused platelet count greater than 20,000/microL (20 x 10(9)/L) occurred on day 10 and 14, respectively. Regimen-related nonhematopoietic toxicity was minimal. All patients improved and/or had stabilization of disease with a follow-up of 5 to 17 months (median, 11 months). We conclude that intense immunosuppressive conditioning and autologous T-cell-depleted hematopoietic transplantation was safely used to treat these 10 patients with severe autoimmune disease. Although durability of response is as yet unknown, all patients have demonstrated stabilization or improvement.

Adoptive immunotherapy may be performed with either autologous or allogeneic lymphocytes. Autologous cellular immunotherapy is hindered by the inability to break anergy or self-tolerance. Advances in this area have focused on the use of tumor-specific lymphocytes activated by antigen-pulsed or transgene modified dendritic cells. Allogeneic cellular immunotherapy is effective even with the use of non-specific and unactivated donor lymphocytes. Allogeneic cellular therapy is, however, complicated by graft-versus-host disease (GVHD). Advances in allogeneic immunotherapy will require better control of GVHD.

Hematopoietic stem cell transplantation is a new therapy for severe autoimmune diseases. Patients who have failed standard therapies and are at high risk of subsequent morbidity and mortality are being considered as candidates. Early results are encouraging. However, the number of patients treated is limited, only short-term follow-up is available, the mechanism of improvement or stabilization is unknown, and the procedure has the potential for life-threatening toxicity.

Relapsing experimental autoimmune encephalomyelitis (R-EAE) is an immune-mediated demyelinating central nervous system (CNS) disease. Myeloablation and syngeneic bone marrow transplantation (SBMT), when performed at the peak of acute disease (day 14), prevented glial scarring and ameliorated the disease severity. In contrast, when syngeneic BMT was performed late in chronic phase (day 78), significant glial scarring remained and the clinical severity did not differ significantly from that of the controls. After SBMT in either the acute or chronic phase of disease, the posttransplant immune system remained responsive to myelin epitopes as determined by in vitro proliferation and interferon-gamma (IFN-gamma) production. However, in mice undergoing SBMT, in vivo delayed-type hypersensitivity (DTH) responses were significantly decreased while IFN-gamma RNA levels and inflammatory infiltrates within the CNS were slightly improved. We conclude that failure of SBMT to improve the clinical disease when performed in chronic phase may be due to preexisting glial scarring. We also conclude that in the absence of glial scarring and irreversible neuronal injury, in vivo DTH responses and histology are better predictors of clinical improvement than in vitro proliferation or IFN-gamma cytokine production.

This study will evaluate the safety and efficacy of allogenic donor lymphocyte infusions in patients who have relapsed hematologic malignancies after allogeneic bone marrow transplantation (BMT). Donor lymphocyte transfusions have resulted in the cure of some patients with relapsed leukemia or lymphoproliferative disorder after allogeneic BMT, but has been complicated by the development of graft versus host disease (GvHD). We hypothesize that a retroviral vector containing the Herpes simplex thymidine kinase (HStk) gene will allow for retention of the anti-leukemia response of transfused donor lymphocytes while allowing for the adverse effects of GVHD to be mitigated. Patients with relapsed hematologic malignancies after allogeneic BMT will be infused with ex vivo gene modified donor lymphocytes. The Herpes Simplex thymidine kinase (HStk) gene will be transduced into the cells ex vivo using LTKOSN. 1 vector supernate. Insertion of the HStk gene into lymphocytes confers a sensitivity to the anti-herpes drug ganciclovir (GCV). This selective destruction of donor lymphocytes in situ will be used to abrogate the effect of graft versus host disease, if it develops.

Most patients with autoimmune diseases are thought to have a a normal life expectancy, and thus are treated conservatively. However, these diseases have a diverse clinical course. A small subset of patients have "severe autoimmune diseases," or SADS, which are rapidly progressive and are associated with early mortality. If patients with SADS can be identified before they develop irreversible organ damage, aggressive intervention would be indicated. Consequently, patients with SADS are now being enrolled in experimental protocols of immune ablation and hematopoietic stem-cell rescue (ie, bone marrow transplantation [BMT] at several US institutions. For various reasons, including the high cost of BMT, it will probably be years before the benefits, if any, of this procedure are known.

In addition to our center (Northwestern University, Chicago), several institutions in the United States (Fred Hutchinson Cancer Center, University of California at Los Angeles, and Medical College of Wisconsin) and Europe are activating protocols to transplant patients with SADS. In this age of cost-effectiveness, it will be difficult to arrange third-party reimbursement for a hematopoietic stem cell transplant that may lead to medical charges of between $100,000 and $200,000. However, the cost of standard medical care for patients with SADS is not trivial. Dialysis for an SLE patient with renal failure costs $40,000 per year, while the medical resources required to care for a patient with progressive multiple sclerosis may exceed $35,000 per year. Unique BMT regimen-related toxicities may occur, including intracranial hemorrhage in the SLE or rheumatoid arthritis patient who has vasculitis; acute neurologic decompensation in patients with multiple sclerosis, especially if the conditioning regimen contains neurotoxic agents that cross a compromised blood-brain barrier; respiratory failure in patients with myasthenia gravis; and increased renal or pulmonary toxicity in patients with scleroderma and parenchymal fibrosis. Scleroderma-associated gastrointestinal dysmotility and bacterial overgrowth may also lead to greater fungal and bacterial infections [76]. BMT is currently considered appropriate therapy for patients with chronic-phase Chronic myelogenous leukemia (CML) and indolent lymphomas who otherwise have a relatively long life expectancy of 5 and 10 years, respectively. The roughly similar long survival but greater functional impairment of patients with SADS may justify consideration of immune ablation and hematopoietic stem cell rescue.

Experimental allergic encephalomyelitis (EAE), an animal model for multiple sclerosis (MS), is a paralytic disease of the central nervous system (CNS) mediated by T-lymphocytes reactive to myelin basic protein (MBP). Lewis rats actively immunized with fragment 68 to 82 of guinea pig MBP develop a monophasic disease with spontaneous recovery. Lymphocyte recognition of the primary encephalitogenic sequence of MBP (fragment 68 to 82) is V beta 8.2 T cell receptor (TCR) skewed [1-3]. Lewis rats in clinical remission at 1 month and 3 months after spontaneous resolution of EAE retain V beta 8.2 T-lymphocytes in the CNS when analyzed by reverse transcriptase polymerase chain reaction or in situ hybridization. In contrast, 1 and 3 months after clinical remission from syngeneic bone marrow transplantation, V beta 8.2 T lymphocytes are absent from the CNS. During clinically active EAE and inflammatory breakdown of the blood-brain barrier, immune ablation and reconstitution with syngeneic bone marrow results in clinical tolerance of the new immune system to myelin.

The authors report four patients whose initial symptom of tumor recurrence or progression was unilateral numbness of the chin. Two patients had Hodgkin lymphoma, one had malignant melanoma, and one had prostate cancer. Physical examination was notable only for unilateral anesthesia of the chin and lower lip. Diagnostic evaluation, including computed tomography (CT) scan and magnetic resonance imaging (MRI) of the brain, plain radiographs of the mandible, and cerebrospinal fluid analysis for protein, glucose, and cytology were normal. Bone scans revealed osseous lesions in the axial skeleton of all patients, whereas only two patients had abnormal uptake in the mandible. The authors conclude that in the setting of a negative evaluation for central nervous system (CNS) or local mandibular disease, mental neuropathy is associated with recurrent or progressive skeletal disease. In addition, to document relapsed or progressive cancer, the skeletal system may have to be examined at sites distant from the mandible.

Increased expression of multidrug-resistance (mdr) gene transcripts and of the encoded protein, P-glycoprotein, is found in many types of tumors. The biological significance of mdr overexpression during the stepwise process of neoplastic development, however, is not well understood. To assess the possible significance of mdr overexpression in carcinogenesis, we examined the cellular distributions of both mdr gene transcripts and P-glycoprotein during hepatocarcinogenesis induced in rats by the Solt-Farber protocol and then compared them to the distributions of the placental form of glutathione S-transferase (GST-P), a known marker of preneoplastic and neoplastic lesions in the liver. In situ hybridization and immunohistochemical techniques were employed. Neither mdr transcripts nor P-glycoprotein was expressed in oval cells that appeared early in the carcinogenic process. GST-P was strongly expressed in the early focal lesions, whereas the levels of mdr transcripts and P-glycoprotein expressed were low and heterogeneous. Expression of mdr transcripts and P-glycoprotein was increased and became more uniform in hyperplastic nodules and carcinomas, although considerable heterogeneity of expression was still found, particularly at the nodular stage. These data suggest that increased expression of mdr is associated with later stages of neoplastic development in the liver. Furthermore, that no chemical treatment of the animals was employed when the expression of mdr was increasing in the preneoplastic and neoplastic lesions suggests that the enhanced mdr expression is intrinsic to the carcinogenic process.

DNA repair processes are critically important in the prevention of carcinogenesis, and currently much research is directed toward elucidation of the biochemical mechanisms by which DNA repair occurs. Techniques have been developed for examining individual genes to quantitate the lesions induced by various chemotherapeutic agents and to measure the rate of gene-specific DNA repair. In mammalian cells, the DNA repair response exhibits intragenomic heterogeneity-active genes are preferentially repaired and the transcribed strand of DNA is repaired more rapidly than the nontranscribed strand. These studies have provided new insight into the molecular biology of DNA repair and a new perspective on the role of repair processes in cellular resistance to DNA damage and malignancy. Elucidation of the mechanisms by which gene-specific lesions are formed and repaired will be important if we are to understand the fundamental processes of malignancy.

Important aspects of the DNA repair mechanisms in mammalian, and especially human, cells are reviewed. The DNA repair processes are essential in the maintenance of the integrity of the DNA and in the defense against cancer. It has recently been discovered that the DNA repair efficiency differs in different regions of the genome and that active genes are preferentially repaired. There is mounting evidence that DNA repair processes play a role in the development of drug resistance by tumor cells. We will discuss such data as well as further approaches to clarify the relationship between DNA repair and antineoplastic drug resistance. Specifically, there is an increasing need to investigate the intragenomic heterogeneity of DNA repair and correlate the repair efficiency in specific genes to aspects of drug resistance. We also discuss the therapeutic potential of inhibiting the DNA repair processes and thereby possibly overcoming drug resistance.

Previous studies by this laboratory have indicated that expression of the multidrug resistance (mdr) gene can be increased in vivo by exposure to a variety of xenobiotics. Because of the nature of these compounds, it was proposed that mdr gene expression might, at least in part, be regulated by the arylhydrocarbon (Ah) receptor. In the present study, we used a primary hepatocyte culture model to examine the relationship between induction of cytochrome P450IA and mdr expression in vitro. Both 3-methylcholanthrene (MC) and 2-acetylaminofluorene (AAF) were efficient inducers of mdr expression in this model. Induction of mdr gene expression by both MC and AAF obeyed a log10 concentration/response relationship. In contrast, 2,3,7,8-tetrachlorodibenzo-P-dioxin did not induce mdr expression at concentrations that yielded maximum induction of cytochrome P450IA expression. These data suggest that mdr induction was not mediated via the Ah receptor. Nuclear run-off analysis indicated that both AAF and MC induced mdr expression by increasing transcription. Primer extension analysis indicated that mdr gene transcription was initiated at one major site 151 bp upstream of the ATG site in both the uninduced and induced state in vivo and in vitro. The sequence of the primer and the site of initiation of gene transcription indicate that the main gene induced was the mdr 1b gene.

P-glycoprotein is a cell membrane transport protein in various human tissues that acts as an efflux pump, apparently to protect normal cells from environmental toxins. It is also a mechanism used by some cancer cells to resist chemotherapy. The gene responsible for P-glycoprotein is partially defined. Agents that inhibit the protein in tumors may make chemotherapy more effective and less toxic.

We have examined the relationship between transformation and multidrug resistance by employing the v-H-ras or v-raf oncogenes to transform rat liver epithelial (RLE) cells in vitro. The data indicate that transformation of RLE cells with v-H-ras or v-raf results in increased resistance to the cytotoxins adriamycin, vinblastine and 2-acetylaminofluorene. This multidrug resistance is accompanied by increasing expression of P-glycoprotein (MDR-1) and glutathione-S-transferase P (GST-P). Thus, neoplastic transformation of RLE cells with v-raf or v-H-ras, independently of chemical exposure, results in multidrug resistance.

The maternal serum concentration of antidiuretic hormone (ADH) in a pregnancy uncomplicated by preeclampsia is identical to the ADH concentration in the nonpregnant female and normal male. However, elevated maternal ADH secondary to fetal hypothalamic ADH production and a genetic defect in maternal vasopressinase may be a cause of preeclampsia.

The levels of mRNA for multidrug-resistance (MDR-1) and selective cytochrome P-450 genes were determined in adult rat liver following administration of various natural and synthetic xenobiotics. MDR-1 (also known as PGY1) was induced following administration of aflatoxin B1, 2-(acetylamino)fluorene (AAF), N-hydroxy-2-(acetylamino)fluorene, isosafrole, phenothiazine, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), but not after phenobarbital or 7-hydroxy-2-(acetylamino)fluorene treatment. Cytochrome P-450 isoform d was induced by TCDD, isosafrole, phenothiazine, and AAF, while cytochrome P-450 isoform b was induced by phenobarbital, and to a lesser extent by isosafrole. These observations suggest that both MDR and cytochrome P-450 gene families are evolutionarily selected by the capacity of various xenobiotics to induce their own detoxification either through metabolism to hydrophilic derivatives by the cytochrome P-450 system or direct excretion from the cell by the MDR gene family. Furthermore, the data indicate that induction of selective members of the MDR and the cytochrome P-450 gene families may depend on overlapping regulatory elements.

We report the cases of four patients with end-stage renal disease and New York Heart Association class III or IV heart failure of nonischemic origin as documented by coronary angiography. Because of left ventricular dysfunction (left ventricular end-diastolic pressure, 23 to 30 mm Hg; ejection fraction, 20% to 35%), all four patients were initially considered poor surgical candidates for renal transplantation. These same four patients became asymptomatic, however, with markedly improved cardiac function (ejection fraction, 43% to 69%) detected as early as 6 and 14 days after renal engraftment. Therefore, there exists a subset of patients with end-stage renal disease in whom congestive heart failure should not be considered a contraindication to renal transplantation. We conclude that some dialysis-dependent patients who manifest symptomatic heart failure of nonischemic origin have a reversible cardiomyopathy and should not be denied renal transplantation.