Biomedical subjects

J H Falkenburg

Publications and source records attributed to J H Falkenburg.

At least 55 records · Page 3Linked to original sources

PubMed1997

TCR gamma delta+ cells expressing Vgamma 9V delta2, which normally predominate the blood, are found in the spleens of patients with hairy cell leukemia.

T cell receptor gamma delta+ (TCR gamma delta+) cells are present in all lymphoid tissues, but at lower frequencies than TCR alpha beta+ cells. In normal spleens, they account for about 15-20% of CD3+ cells. In hairy cell leukemia (HCL), a B cell malignancy with a characteristic involvement of the spleen, splenic T cells of approximately 40% of the examined patients showed a remarkable increase in CD3+ TCR gamma delta+ cells. Therefore, we studied the TCR gamma delta phenotypes in blood and spleen of 12 HCL patients in comparison with normal samples. In normal blood (n= 6) the majority of TCR gamma delta+ cells expressed the Vgamma 9V delta2 phenotype, while in normal spleens (n = 9) a different population was found expressing Vdelta1. In contrast, six of eight paired blood and spleen samples of individual HCL patients demonstrated the same phenotype with predominantly Vgamma 9V delta2 expression. This change in splenic TCR gamma delta usage in patients with HCL might be the result of cell-trapping, or an infiltration of TCR gamma delta+ cells from the blood.

Humans↗

PubMed1997

Detection of CBP rearrangements in acute myelogenous leukemia with t(8;16).

The CREB-binding protein (CBP) is a large nuclear protein that regulates many signal transduction pathways and is involved in chromatin-mediated transcription. The translocation t(8;16)(p11;p13.3) consistently disrupts two genes: the CBP gene on chromosome band 16p13.3 and the MOZ gene on chromosome band 8p11. Although a fusion of these two genes as a result of the translocation is expected, attempts at detecting the fusion transcript by reverse transcriptase polymerase chain reaction (RT-PCR) have proven difficult; to date, only one in-frame CBP/MOZ fusion transcript has been reported. We therefore sought other reliable means of detecting CBP rearrangements. We applied fluorescence in situ hybridization (FISH) and Southern blot analyses to a series of AML patients with a t(8;16) and detected DNA rearrangements of both the CBP and the MOZ loci in all cases tested. All six cases examined for CBP rearrangements have breakpoints within a 13 kb breakpoint cluster region at the 5' end of the CBP gene. Additionally, we used a MOZ cDNA probe to construct a surrounding cosmid contig and detect DNA rearrangements in three t(8;16) cases, all of which display rearrangements within a 6 kb genomic fragment of the MOZ gene. We have thus developed a series of cosmid probes that consistently detect the disruption of the CBP gene in t(8;16) patients. These clones could potentially be used to screen other cancer-associated or congenital translocations involving chromosome band 16p13.3 as well.

Acetyltransferases↗

PubMed1997

Human cytotoxic CD8+ T-lymphocyte clones engraft in severe combined immunodeficient (SCID) mice but show diminished function.

Mice with severe combined immunodeficiency (SCID) provide an in vivo model for studying interactions between human tumor cells and effector cells of the immune system. We studied the behavior of human alloreactive cytotoxic T lymphocytes (CTLs) in SCID mice, including the migration pattern of CD8+ or CD4+ CTL clones to various murine tissues, their engraftment in the absence or presence of recombinant human interleukin 2 (rhIL-2) compared with the engraftment of lymphokine activated killer (LAK) cells, and the in vitro as well as the in vivo function of the engrafted CTL clones. The polymerase chain technique using T-cell-receptor-gamma specific primers revealed the presence of human CD8+ CTL clones in the blood, lungs, and liver of mice receiving rhIL-2 for 14 days, for at least 18 days after intravenous inoculation. Human T cells were transiently detected in the bone marrow, lymph nodes, thymus, and spleen. Although the three CD8+ CTL clones and two CTL lines tested required rhIL-2 for their engraftment, the four LAK cell populations also engrafted in the absence of rhIL-2. In contrast to CD8+ T cells, only low frequencies (<1%) of CD4+ cells could be detected in the blood of the SCID mouse. Engrafted human T cells recovered from the murine blood showed absent or diminished cytotoxicity in vitro against human target cells in five or six experiments, respectively. In addition, when the antitumor activity of engrafted CD8+ clones was investigated in vivo using a xenotransplantation model of human B-cell lymphoma in SCID mice, no significant prolongation of the mean survival time of six treated animals was observed compared with animals treated with rhIL-2 alone. Our results illustrate that although in vitro primed and cultured human CD8+ T cells engraft in SCID mice, their in vitro and in vivo function is impaired.

Animals↗

PubMed1997

Cytotoxic T-lymphocyte (CTL) responses against acute or chronic myeloid leukemia.

In addition to chemotherapy and irradiation, in the context of allogeneic stem cell transplantation (SCT), the donor cell-mediated antileukemic effect can lead to sustained complete remissions, also in cases of a large tumor load. This phenomenon appears to be an immunologically mediated response, possibly due to various effector cell populations. Cytotoxic T-lymphocyte (CTL) responses against minor histocompatibility antigens with restricted tissue distribution, in particular restricted to some or all hematopoietic cells, may be highly efficient in inducing anti-leukemic responses for adoptive immunotherapy. Specific CTL responses against leukemia-associated antigens may be generated using leukemic cells modified to coexpress costimulatory molecules identical to professional antigen-presenting cells. Donor-derived T cells recognizing such antigens may be used in the context of allogeneic SCT to induce complete and sustained remissions, also in patients with leukemia refractory to chemotherapy. In these circumstances, the primary objective of allogeneic SCT may be not to diminish the number of malignant cells by the chemotherapy and irradiation as part of the conditioning regimen, but to allow immunotherapy against leukemic cells using donor lymphocyte populations.

Humans↗

PubMed1997

Characterization of a novel malignant B cell line with t(14;18) and t(4;11) established from a patient with acute monoblastic leukemia.

The severe combined immunodeficient (SCID) mouse model is an important tool with which to study new strategies for treating hematologic neoplasia. For these experiments, a large number of human cell lines growing in SCID mice are a prerequisite. We describe a new Epstein-Barr virus (EBV)-positive B cell line, designated BEVA, with a complex karyotype including translocations t(14:18)(q32;q21) and t(4;11) (q21;q23) that meets this need. As demonstrated by Southern blot analysis, BCL2 at 18q21, but not MLL/ALL1 at 11q23, was involved in these translocations. BEVA cells coexpressed lymphoid (IgG-kappa, CD19, CD20, CD21, and CD24) and myeloid (CD11b, CD15, and CDw65) markers. Interestingly, the cell line was established from the bone marrow culture of a patient with acute myeloid leukemia (AML). Examination of bone marrow biopsy specimens suggested the presence of non-Hodgkin's lymphoma (NHL) in this patient in addition to AML. In vitro and in vivo growth characteristics of the BEVA cell line were compared with the previously described EBV-positive B cell line DoHH2, also carrying a translocation t(14;18)(q32;q21). These DoHH2 cells additionally expressed CD10, whereas, in contrast to BEVA cells, only a small population of DoHH2 cells showed expression of CD44. Both cell lines showed similar growth characteristics in vitro, but reacted differently to cytokines, including interleukin (IL)-4, IL-6, IL-7, and alpha-interferon (IFN). Upon inoculation in SCID mice, marked differences were observed in the dissemination patterns of the BEVA or DoHH2 cells. Although both cell lines circulated in the blood and were predominantly found in murine bone marrow and lymphoid tissues, DoHH2 cells infiltrated the murine spleens, whereas BEVA cells could only rarely be detected in these tissues. In contrast to DoHH2 cells, BEVA cells gave rise to tumor masses in liver, kidney, and para-aortal or mesenteric lymph nodes. The relationship between these in vitro differences and the observed differences in dissemination of both cell lines is discussed.

Animals↗

PubMed1996

Colony growth of human hematopoietic progenitor cells in the absence of serum is supported by a proteinase inhibitor identified as antileukoproteinase.

Serum contains many growth factors and nutrients that stimulate colony formation of hematopoietic progenitor cells (HPC) in semisolid cultures. In the absence of serum, no proliferation of HPCs could be obtained in semisolid medium cultures of partially purified bone marrow cells in the presence of multiple hematopoietic growth factors, insulin, cholesterol, and purified clinical-grade human albumin. This appeared to be due to a suppressive activity induced by monocyte- and T lymphocyte-depleted accessory cells on CD34+ HPCs. Serum-free conditioned medium from the bladder carcinoma cellline 5637 could replace serum to support the growth of HPCs in these cultures. After gel filtration and reverse-phase high-performance liquid chromatography of 5637 supernatants, this activity could be attributed to a 15-kD protein that was further identified by NH2-terminal sequence analysis as the serine proteinase inhibitor antileukoproteinase (ALP). The growth-supportive activity from the 5637 conditioned medium and the (partially) purified fractions could be completely neutralized by a polyclonal rabbit IgG antibody against human ALP (huALP). Similar supportive effects on the growth of HPC could be obtained in the presence of recombinant huALP. We demonstrated that the COOH-terminal domain of ALP containing the proteinase inhibitory activity was responsible for this effect. alpha-1 proteinase inhibitor was capable of similar support of in vitro HPC growth. These results illustrate that proteinase inhibitors play an important role in the in vitro growth of hematopoietic cells by the neutralization of proteinases produced by bone marrow accessory cells. This may be of particular relevance for in vitro expansion of human hematopoietic stem cells in serum-free media.

Amino Acid Sequence↗

PubMed1996

Persistent clonal excess and skewed T-cell repertoire in T cells from patients with hairy cell leukemia.

Hairy cell leukemia (HCL) is characterized by a severe T-cell-mediated immune deficiency. At the same time, spontaneous T-cell activation is noted when splenic T cells are studied in vivo and in vitro. Therefore, we searched for oligoclonal T-cell populations in the blood and spleens of 25 patients with HCL using a T-cell receptor gamma-polymerase chain reaction (TCR gamma-PCR). Subsequently, in 6 patients, the CDR3 length and conformation from 22 different TCRBV subfamilies were analyzed after PCR amplification of cDNA using TCRBV subfamily-specific primers. T cells from 15 of 25 HCL patients showed clonal excess by the TCR gamma-PCR. In fluorescence-activated cell sorted T-cell subsets, more clonal bands were observed than in the unseparated T cells, with most of these in CD8+ subsets, but also in CD4+, CD3+ gamma/delta+, and a double-negative CD3+ alpha/beta+ subset. In other B-cell malignancies, 6 of 16 samples showed oligoclonal T cells, whereas only 2 of 18 normal spleen and blood samples showed abnormal bands. Analysis of the TCRBV subfamilies disclosed in all 6 HCL patients a markedly abnormal pattern, with many clonal bands in 5 to 15 subfamilies, and absent or abnormal weak patterns in another 1 to 8 subfamilies. In comparison, 6 normal samples (2 spleens and 4 blood samples) showed in only 1 blood donor 1 clonal band. Two patients with active HCL but without infections or treatment were tested several times during the course of the disease and showed a complete identical skewed T-cell repertoire with the same oligoclonal T-cell populations. In conclusion, T cells in the blood and spleen of HCL patients show impressive abnormalities with many oligoclonal T-cell populations and a very restricted and skewed TCRBV repertoire.

Base Sequence↗

PubMed1996

Mismatches of minor histocompatibility antigens between HLA-identical donors and recipients and the development of graft-versus-host disease after bone marrow transplantation.

BACKGROUND: Graft-versus-host disease (GVHD) can be a major complication of allogeneic bone marrow transplantation even when the donor and recipient are siblings and share identical major histocompatibility antigens. The explanation may be a mismatch of minor histocompatibility antigens. We previously characterized five minor histocompatibility antigens, HA-1, 2, 3, 4, and 5, that are recognized by T cells in association with the major histocompatibility antigens HLA-A1 an A2. METHODS: We collected peripheral-blood leukocytes from 148 bone marrow recipients and their sibling donors, who were genotypically HLA identical. Fifty pairs were positive for HLA-A1, 117 were positive for HLA-A2, and 19 were positive for both. The pairs were typed with cytotoxic-T-cell clones specific for minor histocompatibility antigens HA-1, 2, 3, 4, and 5. RESULTS: Mismatches of HA-3 were equally distributed among recipients in whom GVHD developed and those in whom it did not. By contrast, a mismatch of only HA-1 was significantly correlated with GVHD of grade II or higher (odds ratio, infinity; P = 0.02) in adults. One or more mismatches of HA-1, 2, 4, and 5 were also significantly associated with GVHD (odds ratio, infinity; P = 0.006) in adults. These associations were not observed in children. CONCLUSIONS: A mismatch of minor histocompatibility antigen HA-1 can cause GVHD in adult recipients of allogeneic bone marrow from HLA-identical donors. Prospective HA-1 typing may improve donor selection and identify recipients who are at high risk for GVHD.

Adolescent↗

PubMed1996

Interleukin-10, interleukin-12, and tumor necrosis factor-alpha differentially influence the proliferation of human CD8+ and CD4+ T-cell clones.

Activation and proliferation of human T lymphocytes in vitro can be obtained by various stimuli including specific antigens, mitogens, and cytokines. Here we describe the effect of interleukin-10, interleukin-12 and tumor necrosis factor-alpha on the interleukin-2 dependent proliferation and function of established human CD4+ and CD8+ alloreactive T-cell clones in the absence of antigen presenting cells. IL-12 and TNF-alpha both demonstrated an inhibitory effect on the proliferation of CD8+ cytotoxic T lymphocyte clones, whereas IL-10 enhanced the proliferation. IL-12-induced inhibition of CD8+ CTL clones was not mediated by the endogenous production of TNF-alpha by these clones. The strong inhibitory effect of IL-12 and TNF-alpha did not result in apoptosis. These cytokines did not alter the cytotoxicity of CD8+ CTL clones. When CD4+ T-cell clones were tested in the absence of APC, no significant change in IL-2-dependent proliferation due to IL-10, IL-12, and TNF-alpha could be measured. Since these effects on established CTL clones are in contrast to the effects of IL-10, IL-12, and TNF-alpha during the induction phase of immune responses, a dichotomy of immunomodulatory cytokines such as IL-10, IL-12, and TNF-alpha early and late in the immune response is suggested.

CD4-Positive T-Lymphocytes↗

PubMed1996

Umbilical cord blood contains normal frequencies of cytotoxic T-lymphocyte precursors (ctlp) and helper T-lymphocyte precursors against noninherited maternal antigens and noninherited paternal antigens.

Umbilical cord blood (UCB) has been successfully used as an alternative source of hematopoietic stem cells for allogeneic transplantation. A relatively low incidence and severity of graft-versus-host disease (GVHD) following UCB transplants has been reported, and it has been suggested that this may be caused by a low frequency of alloreactive lymphocytes in UCB. Low frequencies of alloreactive T lymphocytes in UCB may allow transplantation across major MHC barriers with an acceptable risk of GVHD. We investigated cytotoxic T-lymphocyte precursor (CTLp) and helper T-lymphocyte precursor (HTLp) frequencies in UCB. Normal frequencies of CTLp and HTLp were measured against 1-2 HLA class I and 0-1 HLA-DR mismatched stimulator cells. Since it has been postulated that due to maternal fetal transfusion during pregnancy, fetal blood lymphocytes may become tolerant for noninherited maternal antigens (NIMA), allowing transplantation over certain HLA barriers, reactivity of 24 umbilical cord blood samples was analyzed against both parents. The median frequencies of CTLp against NIMA with 1 class-I mismatch was 79 per 10(6) nucleated cells (range 16-428) and with 2 class I mismatches 121 (range 33-748). CTLp frequencies against noninherited paternal antigens (NIPA) were not statistically different from those against NIMA, with a median of 115 (range 8-336) and 176 (range 50-725) for 1 or 2 HLA class I mismatches, respectively. HTLp frequencies in UCB against parents with 0 or 1 HLA-DR antigen mismatches were similar with respect to NIMA (median 74, range 43-233 and 88, range 16-777, respectively) and NIPA (median 125, range 18-174, and 110, range 28-350, respectively). In four cases, UCB from two HLA-identical siblings was tested against both parents. A correlation between the frequencies of CTLp and HTLp from HLA-identical individuals was found, illustrating that these frequencies are genetically determined. These results illustrate that UCB contains normal frequencies of CTLp and HTLp against MHC alloantigens.

Antigen Presentation↗

PubMed1996

Anti-CD45 and anti-CD52 (Campath) monoclonal antibodies effectively eliminate systematically disseminated human non-Hodgkin's lymphoma B cells in Scid mice.

Severe combined immunodeficient (Scid) mice inoculated with the human (t(14;18)-positive B cell lines DoHH2 and BEVA develop lethal systemically disseminated lymphoma (de Kroon et al., Leukemia 8:1385, and Blood 80 [suppl 1]:436). These models were used to study the therapeutic effect of rat-anti-human CD52 (Campath-1G) or CD45 monoclonal antibodies (mAbs) on systemically disseminated tumor cells and on tumor cells present in solid tumor masses. Both mAbs were effective in inhibiting growth of systemically disseminated malignant cells. When treatment with anti-CD52 or anti-CD45 mAbs at a dose of 30 micrograms/mouse/d for 4 days was started 24 hours after intravenous inoculation of human DoHH2 or BEVA cells, a 3-log kill of tumor cells was observed as measured by prolonged survival. After treatment, surviving animals injected with high numbers of BEVA cells showed tumor masses in liver, kidney, and mesenteric lymph nodes. In contrast to nontreated animals, however, only low numbers of malignant cells were found in peripheral blood, and bone marrow was free of tumor cells. Similarly, after mAb treatment of mice inoculated subcutaneously (sc) with DoHH2 cells, no tumor cells could be found in the bone marrow, and few DoHH2 cells could be detected in the peripheral blood, spleen, liver, kidney, or lung. In contrast, tumor cells present in subcutaneous tumors and axillary lymph nodes were relatively unaffected by mAb therapy. The presence of rat immunoglobulin (Ig) could be demonstrated on surviving tumor cells. The presence of murine macrophages in areas in these tumors that were depleted of DoHH2 cells suggested that the mAb-mediated antitumor effect observed in the Scid mouse model is mediated by cellular mechanisms. Apparently these mechanisms were not sufficient to eliminate the fast-growing tumor cells present in the protected sites. Our results indicate that treatment with anti-CD52 or anti-CD45 mAbs potentially may be useful as adjuvant immunotherapy for systemically disseminated B cell lymphoma.

Animals↗

PubMed1996

Unrelated bone marrow transplantation as a rescue procedure following inadvertent loss of an autologous bone marrow graft.

We report a 27-year-old male patient with acute myeloid leukaemia who was successfully treated with an unrelated bone marrow graft within 7 days following the loss of his autologous bone marrow graft. Several factors were found to be essential in order to locate an HLA-ABDR (DRB1)DQ(DQB1) identical, sex-matched, CMV-negative and ABO compatible donor within a week. These included a common HLA phenotype of the patient, the presence of an experienced donor registry in close proximity to a blood bank associated with an HLA laboratory, a large donor file with fully HLA-ABDR typed donors and the almost exclusive use of blood bank donors as potential bone marrow donors. The possibility of further streamlining the logistics of finding a suitable unrelated bone marrow donor is discussed.

Adult↗

PubMed1996

Minor histocompatibility antigen-specific, leukemia-reactive cytotoxic T cell clones can be generated in vitro without in vivo priming using chronic myeloid leukemia cells as stimulators in the presence of alpha-interferon.

At present, allogeneic bone marrow transplantation (BMT) is the only curative treatment for chronic myeloid leukemia (CML) in chronic phase (CP). The graft-vs.-leukemia (GVL) effect appears to play an important role in this treatment. Direct evidence for a GVL effect has been reported in Ph1-positive CML patients who relapsed after allogeneic BMT and who were treated with leukocyte transfusion from the original marrow donor. Alpha-interferon (alpha-IFN) may have facilitated this GVL effect since many patients were treated with it also. We investigated whether leukemia-reactive cytotoxic T lymphocytes (CTLs) can be generated from human leukocyte antigen (HLA)-genotypically identical sibling bone marrow (BM) donors who donated marrow for two patients with Ph1-positive CML in CP and one patient with Ph1-positive acute lymphoblastic leukemia (ALL). We also investigated alpha-IFN's ability to facilitate the generation of CTLs. In the absence of alpha-IFN, CTL lines with only low cytotoxicity and no CTL clones could be generated. In the presence of alpha-IFN, however, alloreactive, leukemia-reactive CTL lines with high cytotoxicity could be generated, and CD8+ CTL clones could be established with HLA class I restricted minor histocompatibility antigen (mHa)-specific recognition. In a cell-mediated clonogenic cytotoxicity assay, the CTL clones showed specific growth inhibition of leukemic precursor cells from the recipient and a second CML patient, but the clones did not inhibit growth of hematopoietic precursor cells (HPCs) from the donor. The normal HPCs from an unrelated donor with the HLA class I restriction molecule were also recognized by the CTL clones, illustrating that the antigen recognized is not leukemia-specific. The mechanism of the immunomodulating effect by alpha-IFN is not clear. Addition of alpha-IFN to medium did not alter the expression of HLA or adhesion molecules on CML cells. In the treatment of CML, administration of alpha-IFN as adjuvant immunotherapy after allogeneic BMT may increase GVL reactivity.

Animals↗

PubMed1995

Generation of CD4+ cytotoxic T-lymphocyte clones from a patient with severe graft-versus-host disease after allogeneic bone marrow transplantation: implications for graft-versus-leukemia reactivity.

HLA-identical bone marrow transplantation (BMT) is associated with both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) reactivity. Different T-cell subsets from the bone marrow (BM) graft may be responsible for GVHD and GVL reactivity after BMT. In the etiology of GVHD, not only CD8+ but also CD4+ donor T lymphocytes may play an important role. Here we report a patient with chronic myeloid leukemia (CML) who was transplanted with the BM from his HLA-genotypically identical sister. After BMT there was complete engraftment, but the patient died because of acute GVHD grade III-IV in complete remission. Cytotoxic T-lymphocyte (CTL) lines were generated after BMT using the irradiated leukemic cells from the patient as stimulator cells and the donor-originated peripheral blood mononuclear cells, procured from the patient after BMT, as responder cells. The generated CTL lines showed specific lysis of the recipient lymphocytes and leukemic cells in a 51Cr release assay. Two types of CTL clones could be established from these CTL lines, both phenotypically CD4+. Clone type I showed male-specific HLA-DQ5-restricted lysis of the recipient lymphocytes, but not of the circulating relatively mature leukemic cells from the patient. This may be explained by the low HLA-DQ5 expression of the more mature CML cells. Clone type II showed HLA-DR2-restricted minor histocompatibility antigen-specific lysis of the recipient lymphocytes and leukemic cells. Both types of CTL clones showed antigen-specific cell-mediated growth inhibition of the recipient clonogenic leukemic precursor cells. These CD4+ CTL clones produced several activating cytokines including tumor necrosis factor alpha, interferon gamma, granulocyte-macrophage colony-stimulating factor (GM-CSF), and macrophage CSF. Our results illustrate that these CD4+ CTL clones may have induced GVHD directly by cytolysis and indirectly by activating cytokines. Because both types of CTL clones recognized the recipient leukemic progenitor cells, they may also contribute to GVL reactivity after BMT.

Adult↗

PubMed1995

[Umbilical cord blood for replacement of bone marrow for allogeneic transplantation of hematopoietic stem cells. Stichting Eurocord Nederland].

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Blood Banks↗

PubMed1995

Constitutive in vivo cytokine and hematopoietic growth factor gene expression in the bone marrow and peripheral blood of healthy individuals.

We investigated hematopoietic growth factor (HGF) and cytokine gene expression in the bone marrow (BM) and peripheral blood (PB) of healthy individuals as a starting point for delineating the physiologic role of cytokines in steady state hematopoiesis. BM biopsy specimens and PB samples from 7 healthy individuals were analyzed by polymerase chain reaction amplification of reverse-transcribed RNA using gene-specific primer sets. Consistent gene expression in the BM of all 7 individuals was detected for macrophage colony-stimulating factor (CSF), stem cell factor, interleukin-6 (IL-6), IL-7, erythroid-potentiating factor, erythroid-differentiating factor, and insulinlike growth factor 1, all cytokines with reported direct stimulatory effects on in vitro hematopoiesis. Of these, erythroid-potentiating factor and erythroid-differentiating factor appeared to be the only stimulating factors that were also expressed in the PB. Among the cytokines with inhibitory effects on in vitro hematopoiesis IL-4, tumor necrosis factor-alpha (TNF-alpha), TNF-beta, transforming growth factor-beta, and macrophage inflammatory protein-1 alpha were expressed in the BM of the 7 individuals. Except for TNF-alpha, the latter cytokines were also expressed in the PB. Consistent expression in the BM and PB of all tested individuals was also observed for IL-1 beta, IL-1 receptor antagonist, and IL-1 beta converting enzyme, which are all members of the IL-1 family with a possible indirect effect on hematopoiesis. Remarkably, no expression of granulocyte CSF, granulocyte-macrophage CSF, and IL-3 was found in the BM or PB of all investigated individuals (n = 15). This was also the case for IL-1 alpha, IL-2, IL-5, IL-9, IL-12, IL-13, leukemia-inhibiting factor, interferon-gamma, and inhibin. Weak IL-8 and IL-10 expression was found in the BM and/or PB of a minority of investigated individuals. These findings provide insight into which cytokines or HGFs potentially are involved in the autocrine or paracrine regulation of in vivo steady state hematopoiesis. The absence of expression of granulocyte CSF, granulocyte-macrophage CSF, and IL-3 in the BM of healthy individuals implicates that it is highly unlikely that these HGFs are involved in the autocrine or paracrine regulation of constitutive hematopoiesis.

Blood Cells↗

PubMed1995

High-dose Ara-C for remission induction and consolidation of previously untreated adults with ALL or lymphoblastic lymphoma.

Thirty-two patients with untreated ALL (n = 26) or lymphoblastic lymphoma (n = 6) between 17 and 65 years of age were treated with a short remission induction course with VP16-213, amsacrine, intermediate dose Ara-C for 6 days, prednisone and intrathecal methotrexate, followed by a consolidation course with vincristine, amsacrine, high dose Ara-C for 4 days, prednisone and intrathecal methotrexate. After subsequent cranial irradiation, no further maintenance was planned. However, some patients underwent an allogenic (n = 5) or autologous (n = 5) bone marrow transplantation after the consolidation treatment. Twenty-three of 32 patients (72%) achieved a complete remission. Ten of 13 patients with T-ALL or lymphoma, six of eight patients with pre-B or common ALL, and seven of 11 patients with B-ALL or Burkitt's lymphoma achieved a complete remission. The median duration of remission was 24 months. Overall survival for the whole group was 35% at 5 years. The disease-free survival was 45% at 5 years. Long-term survival for patients with B or T-ALL was approximately 60%, compared with 15% for those with common or pre B-ALL. Short term intensive courses including intermediate or high dose Ara-C during remission and consolidation treatment lead to results comparable to those obtained with long-term maintenance regimens. Our regimen may be sufficient for patients with T or B-ALL. Larger randomized studies are needed to investigate the relative importance of our observations.

Adolescent↗

PubMed1995

Recognition of clonogenic leukemic cells, remission bone marrow and HLA-identical donor bone marrow by CD8+ or CD4+ minor histocompatibility antigen-specific cytotoxic T lymphocytes.

We investigated whether minor histocompatibility (mH) antigen-specific cytotoxic T lymphocytes (CTL) can discriminate between leukemic hematopoietic progenitor cells (leukemic-HPC) from AML or CML patients, the HPC from their remission bone marrow (remission-HPC), and normal HPC from their HLA-identical sibling bone marrow donor (donor-HPC). Specific lysis by CD8+ CTL clones was observed not only of the leukemic-HPC but also of the donor-HPC in 3/4 patient/donor combinations expressing mH antigen HA-1, 3/5 combinations expressing mH antigen HA-2, 2/3 combinations expressing mH antigen HA-3, and 2/2 combinations expressing mH antigen HY-A1. In four patient/donor combinations the recognition of the donor-HPC was clearly less than of the leukemic-HPC, indicating differential susceptibility to lysis by these mH CTL clones. In addition, differential recognition of leukemic-HPC and remission-HPC within seven patients was analyzed. In one patient expressing the HA-2 antigen on the leukemic cells the recognition of the remission-HPC was clearly less than of the leukemic-HPC. One CD4+ CTL clone showed specific lysis of the leukemic-HPC from an AML patient and a CML patient as well as of normal remission-HPC and donor-HPC. These results illustrate that in general CD8+ and CD4+ mH antigen specific CTL clones do not differentially recognize leukemic-HPC and normal-HPC. However, differences in susceptibility to lysis of malignant versus normal cells may contribute to a differential GVL effect.

Acute Disease↗