Evidence that specific T lymphocytes may participate in the elimination of chronic myelogenous leukemia

Although the immune system has long been implicated in the control of cancer, evidence for specific and efficacious immune responses in human cancer has been lacking. In the case of chronic myelogenous leukemia (CML), either allogeneic bone marrow transplant (BMT) or interferon-alpha2b (IFN-alpha2b) therapy can result in complete remission, but the mechanism for prolonged disease control is unknown and may involve immune anti-leukemic responses. We previously demonstrated that PR1, a peptide derived from proteinase 3, is a potential target for CML-specific T cells. Here we studied 38 CML patients treated with allogeneic BMT, IFN- alpha2b or chemotherapy to look for PR1-specific T cells using PR1/HLA-A*0201 tetrameric complexes. There was a strong correlation between the presence of PR1-specific T cells and clinical responses after IFN-alpha and allogeneic BMT. This provides for the first time direct evidence of a role for T-cell immunity in clearing malignant cells.     

Immune Reconstitution Kinetics following Intentionally Induced Mixed Chimerism by Nonmyeloablative Transplantation

Establishing mixed chimerism is a promising approach for inducing donor-specific transplant tolerance. The establishment and maintenance of mixed chimerism may enable long-term engraftment of organ transplants while minimizing the use of immunosuppressants. Several protocols for inducing mixed chimerism have been reported; however, the exact mechanism underlying the development of immune tolerance remains to be elucidated. Therefore, understanding the kinetics of engraftment during early post-transplant period may provide insight into establishing long-term mixed chimerism and permanent transplant tolerance. In this study, we intentionally induced allogeneic mixed chimerism using a nonmyeloablative regimen by host natural killer (NK) cell depletion and T cell-depleted bone marrow (BM) grafts in a major histocompatibility complex (MHC)-mismatched murine model and analyzed the kinetics of donor (C57BL/6) and recipient (BALB/c) engraftment in the weeks following transplantation. Donor BM cells were well engrafted and stabilized without graft-versus-host disease (GVHD) as early as one week post-bone marrow transplantation (BMT). Donor-derived thymic T cells were reconstituted four weeks after BMT; however, the emergence of newly developed T cells was more obvious at the periphery as early as two weeks after BMT. Also, the emergence and changes in ratio of recipient- and donor-derived NKT cells and antigen presenting cells (APCs) including dendritic cells (DCs) and B cells were noted after BMT. Here, we report a longitudinal analysis of the development of donor- and recipient-originated hematopoietic cells in various lymphatic tissues of intentionally induced mixed chimerism mouse model during early post-transplant period. Through the understanding of immune reconstitution at early time points after nonmyeloablative BMT, we suggest guidelines on intentionally inducing durable mixed chimerism.     

Feasibility and limitations of bone marrow transplantation in children

Bone marrow transplantation (BMT) has been used increasingly for the treatment of patients with a variety of hematological, immunological and oncological diseases. Originally a highly experimental and often unsuccessful procedure, it has become the treatment modality of choice for selected leukemias, severe aplastic anemia, genetic diseases and solid tumors. Despite the overall success of bone marrow transplantation, a number of serious and potentially fatal complications may occur. Conditioning regimens include chemotherapeutic and radiotherapeutic techniques immunosuppressive enough to allow engraftment of genetically foreign marrow. Graft-versus-host disease (GvHD) is one of the major clinical problems complicating allogeneic BMT. Two forms have been described, acute and chronic GvHD. BMT recipients frequently develop infections complications.     

Bone marrow transplantation results in donor-derived hepatocytes in an animal model of inherited cholestatic liver disease

Cell transplantation is a potential therapy for acquired or inherited liver diseases. Donor-derived hepatocytes (DDH) have been found in humans and mice after bone marrow transplantation (BMT) but with highly variable frequencies in different disease models. To test the effect of liver repopulation after BMT in inherited cholestatic liver diseases, spgp (sister of P-glycoprotein, or bile salt export pump, abcb11) knockout mice, a model for human progressive intrahepatic cholestasis type 2 with defects in excreting bile salts across the hepatocyte canalicular membrane, were transplanted with bone marrow cells from enhanced green fluorescent protein (EGFP) transgenic donor mice after lethal irradiation. One to 6 months later, scattered EGFP-positive DDHs with positive spgp staining were observed in the liver. These hepatocytes had been incorporated into hepatic plates and stained positively with hepatocyte-specific marker albumin. RT-PCR for the spgp gene revealed positive expression in the liver of sgsp knockout mice that had received the transplant. Bile acid analysis of bile samples showed that these mice also had higher levels of total biliary bile acid and taurocholic acid concentration than knockout mice without transplantation, indicating that BMT partially improved biliary bile acid secretion. Our results indicate that bone marrow cells could serve as a potential source for restoration of hepatic functions in chronic metabolic liver disease.     

Defective phagocytosis and clearance of Pseudomonas aeruginosa in the lung following bone marrow transplantation

Bone marrow transplantation (BMT) is an important therapeutic option for a variety of malignant and nonmalignant disorders. Unfortunately, BMT recipients are at increased risk of infection, and in particular, pulmonary complications occur frequently. Although the risk of infection is greatest during the neutropenic period immediately following transplant, patients are still vulnerable to pulmonary infections even after neutrophil engraftment. We evaluated the risk of infection in this postengraftment period by using a well-established mouse BMT model. Seven days after syngeneic BMT, B6D2F(1) mice are no longer neutropenic, and by 3 wk, they demonstrate complete reconstitution of the peripheral blood. However, these mice remain more susceptible throughout 8 wk to infection after intratracheal administration of Pseudomonas aeruginosa; increased mortality in the P. aeruginosa-infected BMT mice correlates with increased bacterial burden in the lungs as well as increased systemic dissemination. This heightened susceptibility to infection was not secondary to a defect in inflammatory cell recruitment to the lung. The inability to clear P. aeruginosa in the lung correlated with reduced phagocytosis of the bacteria by alveolar macrophages (AMs), but not neutrophils, decreased production of TNF-alpha by AMs, and decreased levels of TNF-alpha and IFN-gamma in the bronchoalveolar lavage fluid following infection. Expression of the beta(2) integrins CD11a and CD11c was reduced on AMs from BMT mice compared with wild-type mice. Thus, despite restoration of peripheral blood count, phagocytic defects in the AMs of BMT mice persist and may contribute to the increased risk of infection seen in the postengraftment period.     

Partial 7q Isochromosome in Bone Marrow Following Treatment of Hodgkin's Disease

We report on a 29-year-old female followed for relapsed Hodgkin's disease. She had been diagnosed with Hodgkin's disease at 20 years of age and had been treated with chemotherapy. She had been in remission for six years when she relapsed, at which time she received chemotherapy for bone marrow transplant (BMT). After failure of BMT, she received additional chemotherapies with growth factors and radiation treatment. A bone marrow biopsy showed moderate hypercellularity with erythroid hyperplasia, but the karyotype had an abnormal clone containing an isochromosome derived from a 7q22 deletion.     

The Additive Effect of Mesenchymal Stem Cells and Bone Morphogenetic Protein 2 on γ-Irradiated Bone Marrow in Mice

Irradiation from γ-rays can cause severe damage to bone marrow and hematopoietic tissues. Presently, the most effective method available to treat severe hematopoietic injury is a bone marrow transplant (BMT). Allogeneic BMT is a difficult technique to perform due to the differences in human leukocyte antigen proteins between the donor and recipient, with acute graft-versus-host disease being a major complication of the technique. This limits the widespread applicability of allogeneic BMT. To develop a novel treatment for acute hematopoietic damage, we transplanted bone marrow derived mesenchymal stem cells (MSCs) into recipient mice and treated them with recombinant human bone morphogenetic protein 2 (rhBMP2) to investigate whether MSCs and rhBMP2 could additively promote the restoration of hematopoietic function. MSCs are vital components of the hematopoietic microenvironment that supports hematopoiesis, and bone morphogenic protein is a key factor in hematopoiesis. The 30-day survival rate as well as the numbers of nucleated cells, bone marrow colony-forming unit-granulocyte macrophages, spleen colony-forming units and peripheral blood cells were enumerated. The results showed that, after γ-irradiation and transplantation, MSCs and rhBMP2 additively promoted and improved hematopoietic restoration and function in vivo and in vitro. This additive effect of MSCs and rhBMP2 may one day provide a novel means of treating acute hematopoietic damage.     

T-cell depleted bone marrow transplantation for plasma cell myeloma. Report of a case and review of the results of BMT for myeloma

A 37-year-old male patient with advanced refractory plasma cell myeloma underwent T-cell depleted bone marrow transplantation (BMT) after 7 years of active disease previously treated with combination chemotherapy and irradiation. After the BMT there was marked clinical improvement and the patient is currently in good clinical condition two years after the BMT was performed. However, residual myeloma cells are still seen in the marrow and stable levels of paraprotein are still present in the serum. No GVHD was encountered after BMT. The problems of BMT in myeloma are discussed with a review of the current pertinent literature.     

Adoptive cellular immunotherapy: NK cells and bone marrow transplantation

Allogeneic bone marrow transplantation (BMT) has been increasingly used for the treatment of both neoplastic and non-neoplastic disorders. However, serious obstacles currently limit the efficacy and thus more extensive use of BMT. These obstacles include: graft-versus-host disease (GVHD), relapse from the original tumor, and susceptibility of patients to opportunistic infections due to the immunosuppressive effects of the conditioning regimen.Overcoming these obstacles is complicated by dual outcome of existing regimens; attempts to reduce GVHD by depleting T cells from the graft, result in increased rates of tumor relapse and failure of engraftment. On the other hand, efforts to increase graft-versus-tumor (GVT) effects of the transplant also promote GVHD. In this review, the use of natural killer (NK) cells to overcome some of these obstacles of allogeneic BMT is evaluated. Adoptive immunotherapy using NK cells after allogeneic BMT has several potential advantages. First, NK cells can promote hematopoiesis and therefore engraftment by production of hematopoietic growth factors. Second, NK cells have been shown to prevent the incidence and severity of GVHD. This has been shown to be at least partially due to TGF-beta, an immunosuppressive cytokine. Third, NK cells have been shown to augment numerous anti-tumor effects in animals after BMT suggesting a vital role of NK cells in mediating GVT effects. Finally, NK cells have been demonstrated to affect B cell recovery and function in mice. Therefore, understanding the mechanisms of beneficial effects of NK cells after BMT may lead to significant increases in the efficacy of this procedure.     

Cell-cell cooperation in lymphocyte colony formation: studies in human allogeneic marrow transplantation

The pace of restoration of phytohemagglutinin- (PHA) stimulated lymphocyte colony-forming response was investigated in 50 bone marrow transplant (BMT) recipients (49 allogeneic, 1 syngeneic) studied on 86 occasions. On the majority of occasions (28 of 48), patients studied early (3 to 8 wk) after BMT failed to make detectable lymphocyte colonies, whereas patients studied late (greater than 6 mo) after BMT displayed responses comparable to those of healthy adult volunteers. The sequential study of 10 of the 15 patients with positive lymphocyte colony-forming responses early after BMT revealed that this response is short-lived. The results of recipient donor mixing experiments and experiments involving the addition of the lymphokine interleukin 2 (IL 2) to recipient cells indicated that lymphocytes obtained from unresponsive recipients evaluated early after BMT can be driven to colony formation, and suggest that the major limiting component in such subjects is functional T help.     

Clinical use of rHuEPO in bone marrow transplantation

Recipients of bone marrow (BMT) or peripheral blood progenitor stem cells (PBSCT) transplant have in the period following transplantation a frequent need for red blood cell transfusions and therefore an increased risk of blood-transmitted infections. The anaemia is caused mainly by myelosuppression after high-dose chemotherapy, but an impaired erythropoietin (EPO) production and an inappropriate EPO response may also contribute. Since recombinant human erythropoietin (rHuEPO) has been established as a treatment for renal anaemia it has been of interest whether treatment may be of benefit in the transplant setting. This paper gives an overview of the studies conducted to date with rHuEPO treatment in patients receiving bone marrow transplants. Current data donot support any transfusional benefits when rHuEPO is used in patients receiving autologous transplants. However, in patients receiving allogeneic transplants several studies clearly indicate a therapeutic role for rHuEPO with patients showing accelerated erythroid engraftment, increased haemoglobin levels, a reduced requirement for red blood cell transfusions, and a shortened time to transfusion independence. Especially patients with immune haemolysis after transplantation seems to benefit from the treatment. In addition, rHuEPO treatment has been used for lateonset anaemia after BMT and to prevent the need for homologous red blood cell transfusions to the BMT donor. To reduce costs, it is important in future studies to identify not only the optimal dose and route of administration of rHuEPO but also the most effective combination with other haematopoietic growth factors and cytokines that are used before and after transplantation.     

Clinical aspects of cytomegalovirus infection after allogenic bone marrow grafts

CMV infection is one of the major infection after bone marrow transplantation. CMV viremia was systematically studied in 66 patients with aplastic anemia or leukemia undergoing BMT. 57% patients had CMV viremia with a frequency peak between 7 and 9 weeks after transplant. Clinical symptoms found during viremia were pancytopenia, fever, cytolytic hepatitis. Interstitial pneumonitis was found only in 4 cases. In 3 cases, viremia was not associated with clinical symptoms. Survival was identical to the group of patients without viremia. Viremia was positively associated with the presence of high anti-CMV antibody titer in donor or recipient before transplant, or to a lymphocyte proliferative response against CMV antigens in donor or recipient before BMT. Granulocyte transfusions increased the frequency of CMV viremia. CMV infection was significantly associated with acute and chronic graft versus host disease. The relation showed between these parameters and viremia provides a basis for an accurate diagnosis of CMV infection and a better background for the study of prophylactic or curative treatment of CMV infection.     

针对骨髓移植病患中铁过载的去铁治疗研究进展

骨髓移植是临床上治疗恶性造血系统疾病的常见手段。而铁过载是临床上常见的并发症之一,对病患的造血功能和治疗后恢复有极大的抑制作用。了解铁过载产生的分子或遗传机制能帮助优化去铁化方案,提高去铁化治疗的效率。本文总结了骨髓移植前后铁过载现象发生机制的最新研究进展,并阐述了临床上多种去铁治疗的方案,以期为该类病患铁过载的预防和治疗提供参考。     

Monitoring of active HHV-6 infection in bone marrow transplant recipients by real time PCR; comparison to detection of viral DNA in plasma by qualitative PCR

Twelve (46%) of the 26 patients had human herpesvirus 6 (HHV-6) viremia after bone marrow transplant (BMT). All isolates were recovered from the samples obtained at 2 weeks after BMT. The sensitivity and the specificity of detection of viral DNA in plasma by qualitative polymerase chain reaction (PCR) for monitoring active virus replication were 92% and 97% respectively. Moreover, the positive (85%) and negative (99%) predictive values were also high. The patients with HHV-6 viremia showed a clear peak in HHV-6 DNA in peripheral blood mononuclear cells (PBMCs) at 2 weeks after BMT, which was measured by real time PCR. The virus DNA level in PBMCs between the two groups (patients with viremia and patients without viremia) was statistically different at 2 weeks after BMT (P = 0.033). In patients with HHV-6 viremia, mean HHV-6 DNA copy number was higher in the samples collected at 2 weeks after BMT than the samples collected at any other time period.     

Posttransplantation lymphoproliferative disorder mimicking a nonspecific lymphocytic pleural effusion in a bone marrow transplant recipient. A case report

BACKGROUND: Serous effusions are rare complications of bone marrow transplantation (BMT) and result mainly from infections or tumor relapse. CASE: We report a case of posttransplantation lympho-proliferative disorder (PTLD) revealed by cytodiagnostic examination of serous effusions in a BMT recipient. The effusion was initially considered reactive, but morphologic, immunocytologic and molecular studies subsequently revealed PTLD. CONCLUSION: This case demonstrates the importance of cytologic examination of effusions in BMT or organ recipients. Since most PTLDs are Epstein-Barr virus (EBV)-associated B-cell lymphoproliferative disorders and T cells predominate in reactive effusions, appropriate initial immunostaining, including CD3, CD79a and EBV latent membrane protein, should aid in their early detection.     

Immune ablation and stem-cell therapy in autoimmune disease. Experimental basis for autologous stem-cell transplantation

Treatment of rats suffering from florid chronic progressive systemic arthritis or from chronic remitting/relapsing encephalomyelitis with autologous bone marrow transplantation (BMT) is highly effective. This finding was unexpected as the genotype of the bone marrow largely determines the susceptibility of both spontaneous and induced autoimmune diseases in rodents. The success of autologous stem-cell transplantation depends on the completeness of eradication of the effectors of autoimmune disease, in other words activated and memory T lymphocytes. The reviewed experimental data, when translated to the clinic, indicate that the patients should be subjected to a conditioning regimen that induces maximal lymphoablation and that the autologous transplant has to be T-cell depleted.     

Immune ablation and stem-cell therapy in autoimmune disease: Experimental basis for autologous stem-cell transplantation

Treatment of rats suffering from florid chronic progressive systemic arthritis or from chronic remitting/relapsing encephalomyelitis with autologous bone marrow transplantation (BMT) is highly effective. This finding was unexpected as the genotype of the bone marrow largely determines the susceptibility of both spontaneous and induced autoimmune diseases in rodents. The success of autologous stem-cell transplantation depends on the completeness of eradication of the effectors of autoimmune disease, in other words activated and memory T lymphocytes. The reviewed experimental data, when translated to the clinic, indicate that the patients should be subjected to a conditioning regimen that induces maximal lymphoablation and that the autologous transplant has to be T-cell depleted.     

Immunomodulation after allogeneic bone marrow transplantation by CD4+CD25+ regulatory T cells

Graft-versus-host disease is a major complication after allogeneic bone marrow transplantation (BMT) caused by donor T cells. Immunosuppression mediated by CD4(+)CD25(+) regulatory T cells has been shown to ameliorate such pathogenic immune responses in animal models. Here, we summarize recent findings from experimental and clinical studies and propose a model for peripheral tolerance induction after BMT.     

Hereditary sensory neuropathy type I

Background

Mucopolysaccharidosis type I (MPS I) is a rare lysosomal storage disease subdivided into three phenotypes of increasing severity: Scheie, Hurler-Scheie and Hurler. To gauge the effectiveness of treatments and to determine the load likely to fall on health-care systems, it is necessary to understand the prevalence and natural progression of the disease especially with regard to life-expectancy. In general such data on the natural history of lysosomal storage diseases is sparse.

Methods

Analysis of prevalence and patient survival in MPS I disease using a unique longitudinal data set initiated and maintained over a period of more than 20 years by the Society for Mucopolysaccharide Diseases (UK).

Results

The birth prevalence of MPS I in England and Wales over the period 1981 to 2003 was 1.07/100,000 births and within ± 5% of estimates reported in several studies that examined reasonably large populations. The median survival for MPS I patients (including all phenotypes irrespective of various treatments) was found by Kaplan-Meier analysis to be 11.6 years. This result was driven by the relatively poor survival of patients with the Hurler phenotype who, irrespective of any treatments received, had a median survival of 8.7 years; when censoring for receipt of bone marrow transplant (BMT) was implemented median survival of Hurler patients was diminished to 6.8 years. The difference between these survival curves was statistically significant by log rank test and can be attributed to beneficial effects of BMT and or selection of patients with superior prognosis for intervention with BMT. Survival curves for Hurler patients who received and did not receive BMT were very different. Probability of survival at 2 year after BMT was ~68% and was similar to this after 5 years (66%) and ten years (64%); the mean age of Hurler patients at receipt of BMT was 1.33 years (range 0.1 to 3 years). Follow up was insufficient to determine median survival of the milder phenotypes however, unsurprisingly, this was clearly superior to that for Hurler patients.

Conclusion

The birth prevalence of MPS I in England and Wales is 1.07/100,000 and the median survival for MPS I patients is 11.6 years.     

Long-lasting deficit of functional T cell precursors in human bone marrow transplant recipients revealed by limiting dilution methods

We have applied limiting dilution methods suitable for the estimation of mitogen-reactive helper (pHTL) and cytotoxic (pCTL) T cell frequencies to the analysis of immune function in patients 1 mo to 6 yr after allogeneic bone marrow transplantation (BMT). Although the majority of these patients have regained normal levels of Leu-3+ (helper) and Leu-2+ (killer/suppressor) cells by 6 to 12 mo after BMT as assessed by cytofluorimetry, the fraction of these cells that can function in limiting dilution cultures is substantially below normal levels in nearly all patients. Although some BMT patients eventually recover normal frequencies of pCTL and pHTL, values typically remain greatly depressed even in patients transplanted as many as 4 to 6 yr previously. In contrast, recovery of precursors able to proliferate (without expressing either helper or cytotoxic function) in response to phytohemagglutinin (PHA) and interleukin 2 occurs in many patients by 1 yr after transplant. In spite of the decreased frequency of functional precursor cells found after BMT, each precursor is capable of giving rise to the same amount of function at limiting dilutions as that produced by cells from normal controls. In many BMT patients, proliferation in conventional PHA-stimulated cultures returns to near-normal levels even though precursor frequencies remain low. The limiting dilution method is sensitive to residual immune dysfunction in BMT recipients not easily quantitated by other, more conventional techniques.