PubMed Health⌕ Search

Biomedical subjects

H C Kluin-Nelemans

Publications and source records attributed to H C Kluin-Nelemans.

At least 37 records · Page 2Linked to original sources

Expression and induction of costimulatory and adhesion molecules on acute myeloid leukemic cells: implications for adoptive immunotherapy.

OBJECTIVE: Previously, we observed an increased recognition of malignant cells by cytotoxic T lymphocytes (CTL) when the target cells were cultured in vitro for 24 hours. In this study, we analyzed the expression of costimulatory and adhesion molecules on acute myeloid leukemia (AML) cells and determined whether 24-hour culture of the cells was associated with upregulation of these molecules. We analyzed whether this incubation period improved recognition of AML cells by CTL. MATERIALS AND METHODS: Expression of costimulatory and adhesion molecules on leukemic blasts of 34 patients comprising each AML FAB subclassification were analyzed directly and after 24 hours of culture, and the recognition of these AML cells by an HLA-A2 restricted CTL clone was determined. Blocking studies were performed with antibodies against CD54, CD58, and CD11a. RESULTS: Immunophenotyping showed a low expression of CD80 and CD40 and a variable CD86 expression on most AML cells. CD54 expression was generally low, CD58 expression was high, and CD11a expression was variable, with a higher expression in AML M0, M1, M4, and M5. Twenty-four hours of culture resulted in a significant upregulation of CD40, CD54, and CD58. Impaired recognition of AML cells by the HLA-A2 restricted CTL clone was enhanced 100-200% by 24 hours of preincubation of the leukemic cells. Blocking studies showed the importance of multiple adhesion molecules on the AML cells. CONCLUSION: Low expression of multiple costimulatory and adhesion molecules on AML could be upregulated by 24 hours of culture, which was associated with increased recognition of the AML blasts by CTL. Blocking multiple adhesion molecules completely abolished CTL recognition, showing the importance of the combination of these molecules for T-cell interaction with AML.

Acute Disease↗

Complete remission of accelerated phase chronic myeloid leukemia by treatment with leukemia-reactive cytotoxic T lymphocytes.

Relapse of chronic myeloid leukemia (CML) in chronic phase after allogeneic stem cell transplantation (SCT) can be successfully treated by donor lymphocyte infusion (DLI). However, relapse of accelerated phase CML, blast crisis, or acute leukemia after allogeneic SCT are resistant to DLI in the majority of cases. In vitro-selected and expanded leukemia-reactive T-cell lines may be more effective in inducing an antileukemic response in vivo. To treat a patient with accelerated phase CML after allogeneic SCT, leukemia-reactive cytotoxic T-lymphocyte (CTL) lines were generated from her HLA-identical donor. Using a modification of a limiting dilution assay, T cells were isolated from the donor, selected based on their ability to inhibit the in vitro growth of CML progenitor cells, and subsequently expanded in vitro to generate CTL lines. Three CTL lines were generated that lysed the leukemic cells from the patient and inhibited the growth of leukemic progenitor cells. The CTL did not react with lymphocytes from donor or recipient and did not affect donor hematopoietic progenitor cells. The 3 leukemia-reactive CTL lines were infused at 5-week intervals at a cumulative dose of 3.2 x 10(9) CTL. Shortly after the third infusion, complete eradication of the leukemic cells was observed, as shown by cytogenetic analysis, fluorescence in situ hybridization, molecular analysis of BCR/ABL-mRNA, and chimerism studies. These results show that in vitro cultured leukemia-reactive CTL lines selected on their ability to inhibit the proliferation of leukemic progenitor cells in vitro can be successfully applied to treat accelerated phase CML after allogeneic SCT.

Adult↗

Hairy cell leukemia-specific recognition by multiple autologous HLA-DQ or DP-restricted T-cell clones.

We studied in patients with hairy cell leukemia (HCL) whether autoreactive T cells could be isolated with specific reactivity to the HCL cells. HCL cells were activated via triggering of CD40 on the cell membrane and used as stimulator cells to generate autologous T-cell clones. Two types of CD4(+)BV2(+) T-cell clones with different CDR3 rearrangements and one type of CD4(+)BV8S3(+) T-cell clone were generated from the spleen or blood. These clones specifically recognized the autologous HCL cells, without reactivity to autologous peripheral blood mononuclear cells (PBMC), phytohemagglutinin blasts, or Epstein-Barr virus-transformed B cells in a primed lymphocyte test. Blocking and panel studies using HCL cells from 11 other patients showed that recognition of the HCL cells by the BV2(+) T cells was restricted by HLA-DQA1*03/DQB1*0301, and the BV8S3(+) T cells were restricted by DPB1*04. The T-cell clones did not recognize DPB1*04(+) or DQ3(+) PBMC from healthy donors or DP/DQ matched malignant cells from patients with other hematologic malignancies, except for one patient with acute lymphoblastic leukemia. These HCL-specific T-cell clones may be used for the detection of an HCL-specific tumor antigen.

Animals↗

CD44 expression predicts disease outcome in localized large B cell lymphoma.

Diffuse large B cell non-Hodgkin's lymphomas (DLCL) form a heterogeneous group of tumors with diverse morphology, clinical features, treatment response and prognosis. The biological variables underlying this heterogeneity are unknown. In the present study, we explored the value of the lymphocyte homing receptor CD44, a putative determinant of lymphoma dissemination, in predicting prognosis in DLCL. Expression of the standard form of CD44 (CD44s) and of CD44 isoforms containing exon v6 (CD44v6) on tumor cells was assessed by immunohistochemistry in a cohort of 276 DLCL patients from a population based lymphoma registry. We observed that CD44s as well as CD44v6 expression correlated with tumor dissemination in patients with primary nodal DLCL. Importantly, in patients with localized nodal disease, CD44s was a strong prognosticator predicting tumor related death independent of the other parameters of the International Prognostic Index (IPI). Incorporation of CD44s in the IPI parameter 'stage', increased the prognostic value of this parameter in nodal DLCL. Our data identify CD44 as a biological prognosticator, which can be used to 'fine-tune' the IPI for nodal DLCL.

Adult↗

Treatment, patterns of failure, and survival of patients with Stage I nodal and extranodal non-Hodgkin's lymphomas, according to data in the population-based registry of the Comprehensive Cancer Centre West.

BACKGROUND: Primary extranodal lymphomas (EN-NHLs) are a heterogeneous category of tumors that are considered to be different from primary nodal non-Hodgkin's lymphomas (N-NHLs). To what extent these differences have clinical implications is currently not very clear, because knowledge of EN-NHL as a separate group is limited. METHODS: Using data from the Comprehensive Cancer Centre West (CCCW) population-based NHL registry in the Netherlands, N-NHL and EN-NHL patients were compared to determine differences in characteristics at diagnosis, responses to treatment, patterns of failure, and survival. RESULTS: At presentation, EN-NHL patients had poorer performance scores and more often bulky tumors compared with N-NHL patients, resulting in poorer responses to treatment (complete response rates were 72% and 84%, respectively; P=0.04) and inferior 5-year overall survival (49% and 63%, respectively; P=0.003). Among EN-NHL patients, considerable variations in response, survival, and relapse rates were observed, with gastric NHL patients having the best and central nervous system NHL patients having the worst prognosis (66% and 7% 5-year overall survival, respectively). Relapse rates for N-NHL and EN-NHL patients did not differ (39% and 36% 5-year relapse rates, respectively), whereas among EN-NHL patients considerable differences in relapse rates were noted. Relapses among N-NHL patients were mainly found in nodal sites, whereas recurrent disease in EN-NHL patients was mainly found in extranodal sites. CONCLUSIONS: In this population-based study, Stage I EN-NHL patients as a group had a poorer prognosis than N-NHL patients. However, among EN-NHL patients, considerable differences in response, relapse risk, and survival were observed. The failure analysis conducted in this study suggests that patterns of dissemination for N-NHL and EN-NHL are different.

Brain Neoplasms↗

DNA fiber fluorescence in situ hybridization analysis of immunoglobulin class switching in B-cell neoplasia: aberrant CH gene rearrangements in follicle center-cell lymphoma.

Immunoglobulin class switching usually involves deletion of part of the immunoglobulin CH region. By DNA fiber fluorescence in situ hybridization (FISH) with a barcode of probes covering the DH, JH, and CH genes, the configuration of the entire CH region can be visualized on single DNA molecules. Using this technique, we have studied class switching in three types of B-cell neoplasia, mantle-cell lymphoma (MCL), follicular lymphoma (FL) and hairy cell leukemia (HCL), representing B cells in, respectively, pregerminal center, germinal center, and postgerminal center stages of development. In MCL and FL, simultaneous detection of the t(11;14) and t(14;18) breakpoint with probes for the BCL-1 and BCL-2 loci, respectively, allowed differentiation between productive and nonproductive alleles. In none of 10 MCL cases was class switching detected. In 21 HCL, all nonimmunoglobulin M (IgM) cases had class-switch deletion consistent with the expressed isotype on at least one allele. In FL, however, a peculiar pattern of CH rearrangement was observed. In IgM expressing FL, the translocated alleles had switched in 11 of 13 cases, and the nontranslocated allele showed complex rearrangements downstream from the Cmu-Cdelta genes in 9 of 13 cases. These downstream rearrangements may reflect tumor-specific deregulation of the class-switch machinery. All seven immunoglobulin G (IgG) expressing FL showed class switching on both alleles. Fiber FISH analysis also showed several polymorphisms. The most frequent one, present on 38% of all analyzed alleles, consisted of an extra Cgamma gene or pseudogene in the 3' cluster.

B-Lymphocyte Subsets↗

An in vitro model for cytogenetic conversion in CML. Interferon-alpha preferentially inhibits the outgrowth of malignant stem cells preserved in long-term culture.

IFN-alpha has been shown to prolong survival in chronic myeloid leukemia patients, but its mechanism of action is still not understood. The human cobblestone area-forming cell (CAFC) assay allows for the measurement of the concentration of normal as well as malignant stem cells, while their progeny can be measured in parallel long-term culture (LTC) in flasks. Using CAFC and LTC assays, we have examined direct effects of IFN-alpha (500; 5,000 IU/ml) on the maintenance and outgrowth of CD34-enriched normal and malignant stem cells, obtained from six patients with an established major cytogenetic response to IFN-alpha and from four nonresponding patients. CAFC concentrations were not affected by IFN-alpha. In contrast, IFN-alpha strongly inhibited the clonogenic output in flask LTC. Nucleated cells (NC) produced in LTC were evaluated by fluorescent in situ hybridization (FISH) for the presence of the Philadelphia (Ph) translocation. After 8 wk of LTC, the percentage of Ph+ NCs produced was significantly more inhibited by IFN-alpha in responding patients than in nonresponders. Control LTC without IFN-alpha showed no significant differences of Ph+ NC production between responders and nonresponders. These findings provide the first in vitro model for cytogenetic conversion and suggest that direct antiproliferative effects of IFN-alpha account for the cytogenetic response observed clinically.

Adult↗

Correction of abnormal T-cell receptor repertoire during interferon-alpha therapy in patients with hairy cell leukemia.

Patients with the B-cell malignancy hairy cell leukemia (HCL) exhibit a skewed T-cell repertoire with oligoclonal expression or absence of many members of the T-cell receptor (TCR) BV gene families. To evaluate whether interferon-alpha (IFN-alpha) therapy would not only restore normal hematopoiesis, but also the abnormal T-cell repertoire, we studied T lymphocytes from a cohort of HCL patients treated by IFN-alpha in the past, at initiation, and at several intervals up to 6 years of IFN-alpha treatment. The junctional regions from 22 TCRBV gene families were analyzed after polymerase chain reaction amplification of cDNA (RT-PCR) using family specific primers. In all seven patients improvement of the skewed T-cell repertoire was not seen until 2 years of treatment. It consisted of disappearance of oligoclonal subpopulations and (polyclonal) reappearance of absent TCRBV gene families. The RT-PCR results were correlated with the TCRBV protein expression using TCRBV-specific monoclonal antibodies. T lymphocytes from four patients with active HCL contained large expansions of particular TCRBV-expressing cells (up to 25% of the CD3+ cells; 600 to 700/microL whole blood), which decreased during IFN-alpha therapy in both patients tested. Finally, restoration of the TCR repertoire matched normalization of the functional immune repertoire as measured by proliferative, helper, and cytotoxic T-lymphocyte precursor frequencies against major histocompatibility complex-unrelated individuals. In conclusion, oligoclonal bands of TCRBV gene families found by RT-PCR correspond with a dramatic increase in circulating T lymphocytes expressing the same TCRBV family. Moreover, IFN-alpha can restore the skewed T-cell repertoire and suppress persistent T-cell clones upon treatment of the accompanying malignancy.

Adult↗

A strong expression of CD44-6v correlates with shorter survival of patients with acute myeloid leukemia.

CD44 is a ubiquitous cell-surface glycoprotein that displays many variant isoforms (CD44v) generated by alternative splicing of exons 2v to 10v. The expression of variant isoforms is highly restricted and correlated with specific processes, such as leukocyte activation and malignant transformation. We have herein studied CD44v expression in acute myeloid leukemia (AML) and, for comparison, in normal myelopoiesis. Protein expression of total CD44 and of CD44-3v, -6v, and -9v isoforms has been measured using specific monoclonal antibodies and flow cytometry. The composition of variant exon transcripts has been analyzed by semi-quantitative reverse transcriptase-polymerase chain reaction followed by Southern hybridization with exon-specific probes. Our data show that (1) CD44-6v isoforms are expressed on 12.0% +/- 2.5% of normal CD34(+) cells; this expression is sharply upregulated through monopoiesis and, inversely, downregulated during granulopoiesis. Also, CD44-3v and CD44-9v isoforms are detected on 10% and 14% of normal monocytes, respectively. (2) Sixty-nine from a total of 95 AML patients display a variable proportion (range, 5% to 80%) of CD44-6v+ leukemic cells. (3) A shorter overall survival characterizes the group of AML patients displaying more than 20% of CD44-6v+ leukemic cells (8 months v 18 months, P < .02). These data suggest, for the first time, that the protein expression of CD44-6v containing isoforms may serve as a new prognostic factor in AML.

Acute Disease↗

Gastric lymphomas compared with lymph node lymphomas in a population-based registry differ in stage distribution and dissemination patterns but not in patient survival.

BACKGROUND: Non-Hodgkin's lymphoma (NHL) originating in mucosa-associated lymphoid tissue (MALT) is supposed to have different clinical behavior from lymph node NHL. To test this hypothesis, the authors compared data of gastric NHL patients with lymph node NHL patients in a population-based registry for differences in clinical presentation and prognosis. METHODS: Data from 1981-1989 on patients with primary gastric NHL (n = 109) and patients with primary lymph node NHL (n = 658) were retrieved from a Dutch population-based NHL registry. Patients were compared for stage distribution, involved sites, and survival. The prognostic value of grading lymphomas according to the malignancy grades of the Working Formulation for Clinical Usage was compared with the value of grading MALT NHLs as either low grade or high grade malignancies. RESULTS: Patients with gastric NHL presented more often with localized disease. Stage IV patients had a higher rate of dissemination to other non-lymph node sites but less frequent localization in the bone marrow. The restricted pattern of dissemination was reflected in a significantly lower recurrence rate for gastric NHL. Gastric NHL patients had significantly better disease free survival than lymph node NHL patients (80% and 44% at 5 years, respectively; P < 0.001). In contrast, overall survival did not significantly differ between the two groups, and it appeared to depend on disease stage. Grading MALT lymphoma as either low grade (26%) or high grade (70%) malignancies did not provide better prognostic information than grading according to the Working Formulation for Clinical Usage (low 8%, intermediate 75%, high 9%). CONCLUSIONS: Primary gastric NHL shows a restricted dissemination pattern, which gives support to the MALT lymphoma concept. Although this might explain the superior disease free survival observed for gastric NHL patients, it does not translate into better overall survival for these patients.

Adult↗

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↗

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↗

Direct visualization of dispersed 11q13 chromosomal translocations in mantle cell lymphoma by multicolor DNA fiber fluorescence in situ hybridization.

Several hematologic malignancies are associated with specific chromosomal translocations. Because of the dispersed distribution, chromosomal breakpoints may be difficult to detect using molecular techniques. We present a new application of a recently developed method, DNA fiber fluorescence in situ hybridization (fiber FISH), which allows direct visualization and mapping of chromosomal breakpoints. We tested this method for detection of the t(11;14)(q13;q32) translocation in mantle cell lymphoma. In DNA fiber FISH, a series of fluorochrome-labeled DNA probes covering several hundreds of kilobasepairs is hybridized to linear DNA molecules (or fibers) prepared from frozen tissue or intact cells. By using alternate fluorescent colors, a potential breakpoint region is stained in a color barcode pattern. Breaks in this region will split the barcode in two complementary parts, from which the breakpoint position can be derived. We used a 250-kb barcode covering the BCL-1 locus to detect 11q13 breakpoints in 20 well-characterized mantle cell lymphomas. A t(11;14) was shown by cohybridization of these probes with probes for the Ig heavy chain locus at 14q32. In 18 of 20 mantle cell lymphomas, a breakpoint within the 11q13/BCL-1 barcode was shown by the presence of multiple, complementary translocation products. Fusion of 11q13 and 14q32 sequences on single fibers indicating t(11;14)(q13;q32) was found in all 18 breakpoint-positive mantle cell lymphomas. In one additional case, fusion of an intact 11q13 barcode with 14q32 sequences indicated a breakpoint 100 kb centromeric of the major translocation cluster of BCL-1. Within the 120-kb region of BCL-1, breakpoints were widely scattered. This explains why, so far, a BCL-1 breakpoint had been detected by Southern blot analysis in only 10 of 19 cases. DNA fiber FISH analysis showed a t(11;14) in 95% of mantle cell lymphoma. The results indicate that DNA fiber FISH is a rapid, simple, and equally powerful method for detection of clustered and dispersed translocation breakpoints.

Chromosome Aberrations↗

AP-1 regulates the basal and developmentally induced transcription of the CD11c leukocyte integrin gene.

The p150,95 integrin (CD11c/CD18) mediates leukocyte/endothelium interactions during inflammatory reactions and certain CTL-target interactions, and is also a receptor for fibrinogen, LPS, and the complement component iC3b. CD11c/CD18 is expressed primarily on cells of the myeloid lineage and activated B lymphocytes, and is an important diagnostic marker for hairy cell leukemia. To identify the transcription factors and cis-acting elements involved in the regulated expression of CD11c/CD18 during myeloid cell differentiation and B lymphocyte activation, we have performed structural and functional analysis on the CD11c gene promoter. Electrophoretic mobility shift assays identified an AP-1 binding site (AP1-60) within the proximal promoter region and evidenced differences in the pattern of the Fos family members bound to the AP1-60 element in undifferentiated and differentiated myeloid cells, as well as between B lineage-derived cells. The involvement of the AP1-60 element in DNA-protein interactions was confirmed by means of in vivo footprinting experiments, and its functionality was demonstrated by trans activation of the CD11c promoter by c-Jun. Site-directed mutagenesis of AP1-60 greatly reduced the basal CD11c promoter activity in myeloid and B cells. Furthermore, mutations at AP1-60 inhibited the induction of the CD11c promoter activity during the PMA-triggered U937 cell differentiation, pointing out a key role for the AP-1 transcription factor complex in both the basal and the developmentally regulated expression of the p150,95 leukocyte integrin. The involvement of AP-1 in the transcription of the CD11c gene raises the possibility of altering leukocyte integrin expression by pharmacologic means and will greatly contribute to the characterization of the intracellular signals controlling the expression of leukocyte adhesion molecules.

Base Sequence↗

Hb Malmö [beta-97(FG-4)His-->Gln] leading to polycythemia in a Dutch family.

We have examined six individuals from a two-generation Dutch family for a suspected hemoglobin (Hb) abnormality. The propositus presented with polycythemia and complained of persistent weakness, headache, and epistaxis. All family members initially showed a normal Hb-electrophoretic pattern, but on isoelectric focusing, three of them displayed a fast-moving band associated with high packed red cell volumes (PCV) and increased red blood cell count. The Hb mutant was analyzed at the DNA level by specific gene fragment amplification (PCR), followed by direct DNA sequencing, and the mutation was confirmed by restriction enzyme analysis. We found a C-->G transversion (CAC-->CAG) at codon 97 of the beta-chain, which corresponded to the His-->Gln amino acid substitution previously described as Hb Malmö. We report here the clinical history of the patient, the effects of phlebotomy treatment, and the effect of subnormal iron conditions on the erythropoietic recovery after phlebotomy. The mechanism responsible for the induction of the higher oxygen affinity is discussed, as are some aspects concerning the occurrence, pathology treatment, and the genetic risk of Hb variants with high O2 affinity.

Adult↗

High-dose therapy followed by bone marrow transplantation for relapsed follicular non-Hodgkin's lymphoma. Dutch HOVON Group.

PURPOSE: To analyze whether, in addition to survival, and disease-free survival progression-free interval after transplantation would be longer than the last progression-free interval before transplantation, supporting the argument that high-dose therapy may change the biologic behavior of the disease. PATIENTS AND METHODS: Patients with a poor-risk relapsed follicular NHL were treated with three cycles of doxorubicin 50 mg/m2 and teniposide 60 mg/m2, followed by etoposide 350 mg/m2, cyclophosphamide 60 mg/kg, and TBI and unpurged BMT. RESULTS: Twelve patients were entered in the study. Ten patients fulfilled the criteria for response and underwent transplantation, two of them with an allograft. Nine of ten patients with transplants achieved a complete remission after BMT. One patient died on day 41 due to veno-occlusive disease. The nine patients with transplants who were evaluable for follow-up had a conversion of remission or response duration after transplantation, their progression-free interval after BMT being superior to the last one before BMT with a median of 1044 + days. Overall survival and disease-free survival in the transplant patients after a median follow-up of 1160 days from BMT is 90%. CONCLUSION: High dose chemotherapy followed by stem cell rescue may change the clinical course in follicular non-Hodgkin's lymphoma patients.

Adult↗

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↗