Haploidentical Bone Marrow Stem Cell Research Articles

Haploidentical bone marrow stem cell transplantation for hematological diseases: experience of single public Mexican hospital

Haploidentical bone marrow stem cell transplantation for hematological diseases: experience of single public Mexican hospital

Primary immunodeficiency diseases: dissectors of the immune system.

The past 50 years have seen enormous progress in this field. An unknown concept until 1952, there are now more than 100 different primary immunodeficiency syndromes in the world's literature. Each novel syndrome has shed new insight into the workings of the immune system, dissecting its multiple parts into unique functioning components. This has been especially true over the past decade, as the molecular bases of approximately 40 of these diseases have been identified in rapid succession. Advances in the treatment of these diseases have also been impressive. Antibody replacement has been improved greatly by the development of human immunoglobulin preparations that can be safely administered by the intravenous route, and cytokine and humanized anticytokine therapies are now possible through recombinant technologies. The ability to achieve life-saving immune reconstitution of patients with lethal severe combined immunodeficiency by administering rigorously T-cell-depleted allogeneic related haploidentical bone marrow stem cells has extended this option to virtually all such infants, if diagnosed before untreatable infections develop. Finally, the past 3 years have witnessed the first truly successful gene therapy. The impressive results in X-linked severe combined immunodeficiency offer hope that this approach can be extended to many more diseases in the future.

High levels of interleukin 10 production in vivo are associated with tolerance in SCID patients transplanted with HLA mismatched hematopoietic stem cells.

Transplantation of HLA mismatched hematopoietic stem cells in patients with severe combined immunodeficiency (SCID) can result in a selective engraftment of T cells of donor origin with complete immunologic reconstitution and in vivo tolerance. The latter may occur in the absence of clonal deletion of donor T lymphocytes able to recognize the host HLA antigens. The activity of these host-reactive T cells is suppressed in vivo, since no graft-vs. -host disease is observed in these human chimeras. Here it is shown that the CD4+ host-reactive T cell clones isolated from a SCID patient transplanted with fetal liver stem cells produce unusually high quantities of interleukin 10 (IL-10) and very low amounts of IL-2 after antigen-specific stimulation in vitro. The specific proliferative responses of the host-reactive T cell clones were considerably enhanced in the presence of neutralizing concentrations of an anti-IL-10 monoclonal antibody, suggesting that high levels of endogenous IL-10 suppress the activity of these cells. These in vitro data correlate with observations made in vivo. Semi-quantitative polymerase chain reaction analysis carried out on freshly isolated peripheral blood mononuclear cells (PBMC) of the patient indicated that the levels of IL-10 messenger RNA (mRNA) expression were strongly enhanced, whereas IL-2 mRNA expression was much lower than that in PBMC of healthy donors. In vivo IL-10 mRNA expression was not only high in the T cells, but also in the non-T cell fraction, indicating that host cells also contributed to the high levels of IL-10 in vivo. Patient-derived monocytes were found to be major IL-10 producers. Although no circulating IL-10 could be detected, freshly isolated monocytes of the patient showed a reduced expression of class II HLA antigens. However, their capacity to stimulate T cells of normal donors in primary mixed lymphocyte cultures was within the normal range. Interestingly, similar high in vivo IL-10 mRNA expressions in the T and non-T cell compartment were also observed in three SCID patients transplanted with fetal liver stem cells and in four SCID patients transplanted with T cell-depleted haploidentical bone marrow stem cells. Taken together, these data indicate that high endogenous IL-10 production is a general phenomenon in SCID patients in whom allogenic stem cell transplantation results in immunologic reconstitution and induction of tolerance. Both donor T cells and host accessory cells contribute to these high levels of IL-10, which would suppress the activity of host-reactive T cell in vivo.

Antibody responses to bacteriophage phi X174 in patients with adenosine deaminase deficiency

Adenosine deaminase (ADA) deficiency and its biochemical consequences cause severe combined immunodeficiency (SCID). Treatment strategies, designed to correct the biochemical abnormalities, include transplantation of matched bone marrow or haploidentical bone marrow stem cells, repeated partial exchange transfusions with frozen irradiated human red blood cells (RBC), or weekly injection of polyethylene glycol-modified bovine ADA (PEG-ADA). To evaluate the effect of these therapeutic options, we studied in vitro T-cell function and in vivo antibody responses to the T-cell-dependent neoantigen, bacteriophage phi X174, in 10 children with ADA-deficient SCID. In untreated patients, T-cell function was severely depressed, and only minute amounts of antibacteriophage antibody were produced. Transplantation of bone marrow from a matched sibling (one patient) or a phenotypically matched parent (one patient) resulted in a stable graft, normal T-cell function, and substantial but subnormal antibody titers to bacteriophage, with reduced memory and impaired switch from IgM to IgG. Patients receiving T-cell-depleted haploidentical bone marrow stem cells had markedly depressed antibody responses for as long as 3 years posttransplantation, despite rapidly improving T-cell function that became normal in two of four patients. Two methods of enzyme replacement were explored. During treatment with human RBC transfusions, antibody responses to bacteriophage were as severely depressed as in untreated ADA-deficient patients. Treatment with weekly injections of PEG-ADA resulted in normalization of T-cell numbers in all four patients, normal or near-normal T-cell function in two, and mildly but variably improved T-cell function in the other two patients. Quantitatively and qualitatively normal antibody responses to bacteriophage were observed in three of four patients. Assessment of antibody responses to immunization with bacteriophage phi X174 is a useful method to monitor humoral immune function in treated ADA-deficient patients and can be used to estimate when intravenous immunoglobulin (IVIG) prophylaxis may be safely discontinued.

Antibody Responses to Bacteriophage ϕX174 in Patients With Adenosine Deaminase Deficiency

Abstract Adenosine deaminase (ADA) deficiency and its biochemical consequences cause severe combined immunodeficiency (SCID). Treatment strategies, designed to correct the biochemical abnormalities, include transplantation of matched bone marrow or haploidentical bone marrow stem cells, repeated partial exchange transfusions with frozen irradiated human red blood cells (RBC), or weekly injection of polyethylene glycol-modified bovine ADA (PEG-ADA). To evaluate the effect of these therapeutic options, we studied in vitro T-cell function and in vivo antibody responses to the T-cell-dependent neoantigen, bacteriophage phi X174, in 10 children with ADA-deficient SCID. In untreated patients, T-cell function was severely depressed, and only minute amounts of antibacteriophage antibody were produced. Transplantation of bone marrow from a matched sibling (one patient) or a phenotypically matched parent (one patient) resulted in a stable graft, normal T-cell function, and substantial but subnormal antibody titers to bacteriophage, with reduced memory and impaired switch from IgM to IgG. Patients receiving T-cell-depleted haploidentical bone marrow stem cells had markedly depressed antibody responses for as long as 3 years posttransplantation, despite rapidly improving T-cell function that became normal in two of four patients. Two methods of enzyme replacement were explored. During treatment with human RBC transfusions, antibody responses to bacteriophage were as severely depressed as in untreated ADA-deficient patients. Treatment with weekly injections of PEG-ADA resulted in normalization of T-cell numbers in all four patients, normal or near-normal T-cell function in two, and mildly but variably improved T-cell function in the other two patients. Quantitatively and qualitatively normal antibody responses to bacteriophage were observed in three of four patients. Assessment of antibody responses to immunization with bacteriophage phi X174 is a useful method to monitor humoral immune function in treated ADA- deficient patients and can be used to estimate when intravenous immunoglobulin (IVIG) prophylaxis may be safely discontinued.

Development of multiple monoclonal serum immunoglobulins (multiclonal gammopathy) following both HLA-identical unfractionated and T cell-depleted haploidentical bone marrow transplantation in severe combined immunodeficiency

We have identified five patients with severe combined immunodeficiency (SCID) who developed multiple monoclonal serum immunoglobulin components (multiclonal gammopathy) following bone marrow transplantation. Four patients received haploidentical bone marrow stem cells depleted of T cells and other mature marrow cells by soy lectin agglutination and/or sheep erythrocyte rosetting. One patient received unfractionated HLA-identical bone marrow. Twenty-one distinct paraproteins were detected: 14 IgG, 5 IgM, and 2 IgA, all containing either kappa or lambda light chains. In the haploidentical stem-cell recipients, these monoclonal immunoglobulins appeared immediately prior to, or concomitant with, a rise in T-cell numbers and function. Resolution or diminution of this multiclonal gammopathy occurred as T-cell function was established. Posttransplant karyotypic analyses revealed PHA-stimulated T cells to be of donor origin in all patients. Karyotyping of B-cell lines posttransplantation revealed them to be 100% donor in the patient receiving unfractionated HLA-identical marrow and 100% host (1/4), 100% donor (1/4), mixed (1/4), or not tested (1/4) in the patients receiving haploidentical marrow stem cells. There was no evidence of Epstein-Barr virus (EBV) infection in any of the patients. All patients are currently alive and well. Immunoglobulin synthesis is normal in the patient who received the HLA-identical marrow but remains below normal in the four patients who received T cell-depleted haploidentical stem cells. The posttransplantation development of monoclonal immunoglobulins in the absence of EBV infection did not adversely affect the outcome of either HLA-identical marrow or haploidentical stem-cell grafting.(ABSTRACT TRUNCATED AT 250 WORDS)

Modified MHC restriction of donor-origin T cells in humans with severe combined immunodeficiency transplanted with haploidentical bone marrow stem cells.

The choice of class II MHC determinants that serve as self-recognition elements for murine CD4+ T cells is thought to be determined by the environment in which T cells mature rather than their genotype. Patients with severe combined immunodeficiency (SCID) reconstituted with T cell depleted haploidentical parental stem cells provide an excellent model for studying this phenomenon in humans. After engraftment, the T cells that develop in these infants are all of donor origin. We sought to determine whether the successful immune reconstitution observed in two such SCID chimeras involved modification of the MHC restriction of Ag recognition by the genetically donor T cells as they matured to become competent T cells in the infants' microenvironment. A tetanus toxoid (TT)-specific T cell line and TT-specific T cell clones were established from the blood of two reconstituted SCID patients and from their maternal donors. T cell responsiveness was determined by [3H]thymidine incorporation after TT presentation by EBV-transformed B cell lines (EBV-B) from various donors. The TT-specific T cell line from patient 1 proliferated when presented Ag by patient, maternal donor, and paternal APC. A CD4+ donor origin clone that proliferated when presented TT by patient and paternal EBV-B, but not by maternal donor EBV-B, was isolated from each patient. TT recognition by these clones was shown to be restricted by the HLA DR determinant shared by patient and father, but not present in the donor. Four TT-specific clones isolated from maternal donors failed to proliferate when presented TT by the appropriate paternal EBV-B. These studies demonstrate that, in these human SCID bone marrow chimeras, engrafted donor-origin stem cells maturing to competent T cells in the recipient microenvironment are capable of utilizing recipient HLA determinants as restriction elements for Ag recognition. This suggests that human, as well as murine, MHC restriction patterns for Ag recognition by CD4+ T cells are environmentally determined.

273 Modified T cell MHC restriction following successful haploidentical bone marrow stem cell transplantation in severe combined immunodeficiency disease (SCID)

273 Modified T cell MHC restriction following successful haploidentical bone marrow stem cell transplantation in severe combined immunodeficiency disease (SCID)

Modified responses to recipient and donor B cells by genetically donor T cells from human haploidentical bone marrow chimeras.

After administration of haploidentical stem cells to infants with severe combined immunodeficiency disease (SCID), mature T cells of donor karyotype appear later in the recipient without causing graft-vs-host disease (GVHD). To investigate the effect of the host microenvironment on these genetically donor T cells, mixed leukocyte cultures were carried out. Unfractionated mononuclear cells (MNC) from eight infants with SCID immunologically reconstituted by haploidentical bone marrow stem cells responded in the same pattern as MNC from non-chimeric individuals to autologous and allogeneic irradiated MNC, even though they contained all genetically donor T cells and all genetically patient B cells and monocytes. This included surprisingly vigorous proliferative responses of the patients' MNC to the original donors' irradiated MNC. This autoreactivity could be detected as soon as T cell function appeared post-transplantation and appeared to increase with time. It could be blocked by the addition of monoclonal antibodies to HLA Class II antigens. Responses of most patients' MNC were similar whether stimulated by irradiated MNC from the donor or non-donor parent or by those from unrelated normal controls. Purified genetically donor T cells that had matured from stem cells in the patient's microenvironment responded vigorously to purified donor B cells. These same cells responded much less to patient B cells. In six cases, such genetically donor T cells responded less to patient B cells than fresh donor T cells did to donor B cells in the autologous mixed leukocyte response. By contrast, T cells of donor karyotype from three of the patients responded more vigorously to donor B cells than fresh donor T cells did. Thus, genetically donor T lymphocytes that had matured from stem cells in the recipient microenvironment behaved differently from those that had matured in the donor. The hyporesponsiveness of genetically donor T cells from the patient to patient B cells does not appear to be due to T suppressor cells.

Development of immunity in human severe primary T cell deficiency following haploidentical bone marrow stem cell transplantation.

Recent advances in the prevention of graft-vs-host disease (GVHD) have allowed the use of haploidentical bone marrow cells for correction of lethal genetic defects of the immune system. Sequential analyses of blood lymphocyte phenotypes and functions were done before and after transplantation of haploidentical marrow stem cells into 17 infants with severe primary T cell deficiencies. The marrow was depleted of post-thymic T cells and most other mature marrow cells by soy lectin agglutination and sheep erythrocyte rosetting. The studies were performed to define the time course and extent of appearance of immune function, and to identify factors leading to resistance to engraftment. No pretransplant immunosuppression was used. T cell function was detected between 34 and 287 days after transplantation, but a sharp rise usually occurred between 84 and 115 days, and normal function was reached between 113 and 210 days. Fifteen of the patients are alive from 6 to 41 mo post-transplantation, 12 have improved or have normal T lymphocyte function, and nine have proven T cell chimerism. Increased immunoglobulins of several isotypes have been noted in 11 patients and specific antibodies in seven patients, although B cell chimerism has been detected in only one patient. B cell function required 2 to 2.5 yr for normalization. No GVHD occurred in 14 patients, and the other three had only transient mild skin rashes. Two patients died of viral infections. Failure to engraft was correlated with some pre-transplant lymphocyte responses to mitogens and allogeneic cells (three cases), but not with the presence of pre-transplant natural killer cell function (five cases) nor with the presence of purine salvage pathway enzyme deficiencies (four cases). The latter, however, was associated with poor lymphoid function in two patients. These studies indicate that the thymic microenvironment of most infants with severe combined immunodeficiency disease is capable of differentiating donor stem cells to mature and functioning T lymphocytes which can cooperate with apparently normal host B cells for antibody production.