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J J van Dongen

Publications and source records attributed to J J van Dongen.

At least 19 recordsLinked to original sources
PubMed2004

[Widely divergent clinical phenotype of x-linked agammaglobulinemia in two cousins].

X-linked agammaglobulinaemia (XLA) is a primary immunodeficiency caused by a mutation in the gene encoding Bruton's tyrosine kinase (BTK). The classical presentation of XLA consists of the almost complete absence of B-lymphocytes and immunoglobulins in the peripheral blood leading to severe, mainly bacterial, upper and lower respiratory-tract infections already in early childhood. Irrespective of the kind of BTK-gene mutation the phenotype of XLA can be very diverse. Two 9-year-old cousins with the same BTK-gene mutation illustrate this phenotypical diversity. One boy had a classical presentation and was on maintenance treatment with intravenous immunoglobulins and prophylactic antibiotics to control his infections. Without any prophylactic treatment, his cousin had no abnormal infectious course despite very low B-lymphocyte counts and immunoglobulin levels in the blood. The mechanisms underlying the phenotypical diversity of XLA have not been clarified. Gene polymorphisms affecting the innate immune system may play a role.

Agammaglobulinemia↗
PubMed2001

Basic helix-loop-helix proteins E2A and HEB induce immature T-cell receptor rearrangements in nonlymphoid cells.

T-cell receptor (TCR) gene rearrangements are mediated via V(D)J recombination, which is strictly regulated during lymphoid differentiation, most probably through the action of specific transcription factors. Investigated was whether cotransfection of RAG1 and RAG2 genes in combination with lymphoid transcription factors can induce TCR gene rearrangements in nonlymphoid human cells. Transfection experiments showed that basic helix-loop-helix transcription factors E2A and HEB induce rearrangements in the TCRD locus (Ddelta2-Ddelta3 and Vdelta2-Ddelta3) and TCRG locus (psi Vgamma7-Jgamma2.3 and Vgamma8-Jgamma2.3). Analysis of these rearrangements and their circular excision products revealed some peculiar characteristics. The Vdelta2-Ddelta3 rearrangements were formed by direct coupling without intermediate Ddelta2 gene segment usage, and most Ddelta2-Ddelta3 recombinations occurred via direct coupling of the respective upstream and downstream recombination signal sequences (RSSs) with deletion of the Ddelta2 and Ddelta3 coding sequences. Subsequently, the E2A/HEB-induced TCR gene recombination patterns were compared with those in early thymocytes and acute lymphoblastic leukemias of T- and B-lineage origin, and it was found that the TCR rearrangements in the transfectants were early (immature) and not necessarily T-lineage specific. Apparently, some parts of the TCRD (Vdelta2-Ddelta region) and TCRG genes are accessible for recombination not only in T cells, but also in early B-cells and even in nonlymphoid cells if the appropriate transcription factors are present. The transfection system described here appeared to be useful for studying the accessibility of immunoglobulin and TCR genes for V(D)J recombination, but might also be applied to study the induction of RSS-mediated chromosome aberrations.

Animals↗
PubMed2001

Molecular and flow cytometric analysis of the Vbeta repertoire for clonality assessment in mature TCRalphabeta T-cell proliferations.

Clonality assessment through Southern blot (SB) analysis of TCRB genes or polymerase chain reaction (PCR) analysis of TCRG genes is important for diagnosing suspect mature T-cell proliferations. Clonality assessment through reverse transcription (RT)-PCR analysis of Vbeta-Cbeta transcripts and flow cytometry with a Vbeta antibody panel covering more than 65% of Vbeta domains was validated using 28 SB-defined clonal T-cell receptor (TCR)alphabeta(+) T-ALL samples and T-cell lines. Next, the diagnostic applicability of the V(beta) RT-PCR and flow cytometric clonality assays was studied in 47 mature T-cell proliferations. Clonal Vbeta-Cbeta RT-PCR products were detected in all 47 samples, whereas single Vbeta domain usage was found in 31 (66%) of 47 patients. The suspect leukemic cell populations in the other 16 patients showed a complete lack of Vbeta monoclonal antibody reactivity that was confirmed by molecular data showing the usage of Vbeta gene segments not covered by the applied Vbeta monoclonal antibodies. Nevertheless, this could be considered indirect evidence for the "clonal" character of these cells. Remarkably, RT-PCR revealed an oligoclonal pattern in addition to dominant Vbeta-Cbeta products and single Vbeta domain expression in many T-LGL proliferations, providing further evidence for the hypothesis raised earlier that T-LGL derive from polyclonal and oligoclonal proliferations of antigen-activated cytotoxic T cells. It is concluded that molecular Vbeta analysis serves to assess clonality in suspect T-cell proliferations. However, the faster and cheaper Vbeta antibody studies can be used as a powerful screening method for the detection of single Vbeta domain expression, followed by molecular studies in patients with more than 20% single Vbeta domain expression or large suspect T-cell populations (more than 50%-60%) without Vbeta reactivity.

Adolescent↗
PubMed2001

Efficacy and safety of gemtuzumab ozogamicin in patients with CD33-positive acute myeloid leukemia in first relapse.

PURPOSE: Three open-label, multicenter trials were conducted to evaluate the efficacy and safety of single-agent Mylotarg (gemtuzumab ozogamicin; CMA-676; Wyeth Laboratories, Philadelphia, PA), an antibody-targeted chemotherapy agent, in patients with CD33-positive acute myeloid leukemia (AML) in untreated first relapse. PATIENTS AND METHODS: The study population comprised 142 patients with AML in first relapse with no history of an antecedent hematologic disorder and a median age of 61 years. All patients received Mylotarg as a 2-hour intravenous infusion, at a dose of 9 mg/m(2), at 2-week intervals for two doses. Patients were evaluated for remission, survival, and treatment-emergent adverse events. RESULTS: Thirty percent of patients treated with Mylotarg obtained remission as characterized by 5% or less blasts in the marrow, recovery of neutrophils to at least 1,500/microL, and RBC and platelet transfusion independence. Although patients treated with Mylotarg had relatively high incidences of myelosuppression, grade 3 or 4 hyperbilirubinemia (23%), and elevated hepatic transaminase levels (17%), the incidences of grade 3 or 4 mucositis (4%) and infections (28%) were relatively low. There was a low incidence of severe nausea and vomiting (11%) and no treatment-related cardiotoxicity, cerebellar toxicity, or alopecia. Many patients received Mylotarg on an outpatient basis (38% and 41% of patients for the first and second doses, respectively). Among the 142 patients, the median total duration of hospitalization was 24 days; 16% of patients required 7 days of hospitalization or less. CONCLUSION: Administration of the antibody-targeted chemotherapy agent Mylotarg to patients with CD33-positive AML in first relapse induces complete remissions with what appears to be a favorable safety profile.

Acute Disease↗
PubMed2001

Targeting of the CD33-calicheamicin immunoconjugate Mylotarg (CMA-676) in acute myeloid leukemia: in vivo and in vitro saturation and internalization by leukemic and normal myeloid cells.

Antibody-targeted chemotherapy is a promising therapy in patients with acute myeloid leukemia (AML). In a phase II study of Mylotarg (CMA-676, gemtuzumab ozogamicin), which consists of a CD33 antibody linked to calicheamicin, saturation and internalization by leukemic and normal myeloid cells were analyzed in 122 patients with relapsed AML. Peripheral blood samples were obtained just before and 3 and 6 hours after the start of the first and second Mylotarg treatment cycles. Within 3 to 6 hours after infusion, near complete saturation of CD33 antigenic sites by Mylotarg was reached for AML blasts, monocytes, and granulocytes, whereas Mylotarg did not bind to lymphocytes. Saturation levels prior to the start of the second Mylotarg treatment cycle were significantly increased compared with background levels before the start of the first cycle. This apparently was caused by remaining circulating Mylotarg from the first treatment cycle (approximately 2 weeks earlier). On binding of Mylotarg to the CD33 antigen, Mylotarg was rapidly internalized, as determined by the decrease in maximal surface membrane Mylotarg binding. Internalization of Mylotarg was also demonstrated in myeloid cells in vitro and was confirmed by confocal laser microscopy. In vitro studies using pulse labeling with Mylotarg showed a continuous renewed membrane expression of CD33 antigens, which can significantly increase the internalization process and thereby the intracellular accumulation of the drug. Finally, Mylotarg induced dose-dependent apoptosis in myeloid cells in vitro. These data indicate that Mylotarg is rapidly and specifically targeted to CD33(+) cells, followed by internalization and subsequent induction of cell death.

Adult↗
PubMed2001

Ordered recombination of immunoglobulin light chain genes occurs at the IGK locus but seems less strict at the IGL locus.

Regulation of allelic and isotypic exclusion of human immunoglobulin (Ig) light-chain genes was studied in 113 chronic B-cell leukemias as a "single-cell" model that allowed complete analysis of each light chain allele. Our data show that monospecific Ig light chain expression is in about 90% of cases determined by ordered recombination: Igkappa gene (IGK) rearrangements, followed by IGK deletions and Iglambda gene (IGL) rearrangements, resulting in the presence of only one functional Ig light chain rearrangement. In about 10% (10 cases), 2 functional Ig light chain rearrangements (IGK/IGL or IGL/IGL, but not IGK/IGK) were identified. This might be explained by the fact that regulation of the ordered recombination process is not fully strict, particularly when the IGL locus is involved. Unfavorable somatic mutations followed by receptor editing might have contributed to this finding. Eight of these 10 cases indeed contained somatic mutations. In cases with 2 functional Ig light chain rearrangements, both alleles were transcribed, but monospecific Ig expression was still maintained. This suggests that in these cases allelelic exclusion is not regulated at the messenger RNA level but either at the level of translation or protein stability or via preferential pairing of Ig light and Ig heavy chains. Nevertheless, ordered rearrangement processes are the main determinant for monospecific Ig light chain expression.

Alleles↗
PubMed2001

Molecular discrimination between relapsed and secondary acute lymphoblastic leukemia: proposal for an easy strategy.

BACKGROUND: Discrimination between late relapse of acute lymphoblastic leukemia (ALL) and secondary ALL might be clinically important, because the former might still respond favorably to chemotherapy and/or bone marrow transplantation, whereas secondary ALL is associated with poor prognosis. PROCEDURE: We present a pre-B-ALL patient in whom disease recurred 2 years after completion of treatment. Differences in cytomorphology and immunophenotyping raised a suspicion of secondary ALL. We performed detailed molecular studies of immunoglobulin and T-cell receptor genes for discrimination between relapsed and secondary ALL. RESULTS: Southern blot analysis showed an oligoclonal immunoglobulin heavy chain (IGH) gene configuration at diagnosis and a monoclonal configuration at relapse. The size of one of the rearranged bands at relapse was identical to one of the faint rearranged bands at diagnosis. However, heteroduplex PCR analysis demonstrated that none of the clonal IGH gene rearrangements at diagnosis and at relapse was fully identical. Sequencing of several clonal PCR products revealed an identical DH6-13<-->JH6b junction shared by two different rearrangements at diagnosis and one rearrangement at relapse, thereby proving the clonal relationship between diagnosis and late relapse in this patient. CONCLUSIONS: We propose a stepwise molecular approach for discrimination between relapsed and secondary ALL based on the rapid and cheap heteroduplex PCR technique, including mixing of clonal (homoduplex) PCR products identified at diagnosis and at relapse. Direct sequencing and comparative sequence analysis of IGH gene rearrangements at diagnosis and at relapse should be regarded as an ultimate standard, but can be limited to the rare cases, in which no identical clonal PCR products at diagnosis and at relapse were detected with the mixed heteroduplex PCR analyses.

Blotting, Southern↗
PubMed2001

T cell receptor excision circles as markers for recent thymic emigrants: basic aspects, technical approach, and guidelines for interpretation.

T cell differentiation in the thymus is characterized by a hierarchical order of rearrangement steps in the T cell receptor (TCR) genes, resulting in the joining of V, D, and J gene segments. During each of the rearrangement steps, DNA fragments between rearranging V, D, and J gene segments are deleted as circular excision products, the so-called TRECs (T cell receptor excision circles). TRECs are assumed to have a high over-time stability, but they can not multiply and consequently are diluted during T cell proliferation. It was recently suggested that quantitative detection of TRECs would allow for direct measurement of thymic output. The deltaRec-psiJalpha TREC appears to be the best marker, because the majority of thymocyte expansion occurs before this TREC is formed. However, apart from thymic output several other factors determine the TREC content of a T cell population, such as cell division and cell death. Likewise, the number of TRECs depends not only on thymic output, but also on the longevity of naive T cells. This warrants caution with regard to the interpretation of TREC data as measured in healthy and diseased individuals. deltaRec-psiJalpha TREC detection is a new and elegant tool for identification of recent thymic emigrants in the periphery, but further research is required for making quantitative estimations of thymic output with the use of TREC analysis.

Animals↗
PubMed2001

Flow cytometric immunophenotyping in the diagnosis and follow-up of immunodeficient children.

From time to time, paediatricians are confronted with children who might suffer from a primary immunodeficiency disease. For practical purposes, these children can be divided into four main clinical categories: (1) a relatively large group of children with recurrent ear-nose and throat and lower respiratory tract infections, in some cases caused by deficiencies of antibodies or complement; (2) children with failure to thrive, intractable diarrhoea or an opportunistic infection which can be caused by a T-lymphocyte or combined immunodeficiency; (3) children with infections with pyogenic bacteria or fungi as seen in case of granulocyte/monocyte function deficiency; and (4) a small heterogeneous group of children with recurrence of particular infections. Also, acquired immunodeficiency becomes a more common problem in paediatric practice. Flow cytometric immunophenotyping of leucocytes appears to be an efficient and rapid tool in the diagnosis and follow-up of immunodeficient patients, supporting early recognition, before serious infections have compromised the child's general condition. This technique can now be performed in many hospitals. In this review, we give directions for the use of flow cytometric immunophenotyping of leucocytes in the diagnosis and follow-up of immunodeficient children according to the four main clinical categories.

Child↗
PubMed2001

Reviewing Omenn syndrome.

UNLABELLED: Omenn syndrome is a form of severe combined immunodeficiency associated with high mortality. Early recognition is required in order to initiate life-saving therapy. This review provides information on the clinical symptoms, laboratory parameters and pathology of the disease, supporting early diagnosis in suspected patients. A literature search was performed using Medline, encompassing the period 1965-1999. Sixty-seven cases were identified and with the addition of a recently diagnosed patient at our hospital, 68 children were included. Median age at onset of symptoms was 4 weeks. Key symptoms were erythematous rash (98%), hepatosplenomegaly (88%), lymphadenopathy (80%), often accompanied by recurrent infections (72%) and alopecia (57%). An elevated WBC (55%) was frequently observed, due to eosinophilia and/or lymphocytosis. B-cell counts were significantly decreased whereas T-cell counts were elevated. A high serum IgE was another frequent finding (91%). Therapeutic options include bone marrow transplantation or cord blood stem cell transplantation; however, the mortality still was 46%. CONCLUSION: Omenn syndrome is a fatal disease if untreated. The mortality may be reduced when diagnosis is established early and treatment is initiated rapidly by using early compatible bone marrow transplantation or cord blood stem cell transplantation.

Bone Marrow Transplantation↗
PubMed2001

Minimal residual disease in leukaemia patients.

Because of developments in diagnosis of haemopoietic malignant diseases during the past two decades, routine and reliable identification of very low numbers of malignant cells, known as minimal residual disease (MRD), is now possible. Several large-scale studies have shown that monitoring of MRD in haemopoietic malignant disease predicts clinical outcome. In acute lymphoblastic leukaemia, MRD detection is useful for evaluating early response to treatment and consequently for improving stratification, including treatment reduction. In acute promyelocytic leukaemia and chronic myeloid leukaemia, MRD information at specific time points enables effective early treatment intervention. MRD monitoring is also possible in other leukaemia subtypes, but in these disorders the clinical value of MRD detection is not yet known.

Adult↗
PubMed2001

Immunoglobulin lambda isotype gene rearrangements in B cell malignancies.

The human immunoglobulin lambda (IGL) locus contains seven J-Clambda gene regions of which only J-Clambda1, J-Clambda2 J-CA3 and J-Clambda7 encode the four Iglambda isotypes, ie Mcg, Ke-Oz-, Ke-Oz+, and Mcp, respectively. We used isotype-specific DNA probes for detection of IGL gene rearrangements in 212 B cell malignancies: 76 precursor B cell acute lymphoblastic leukemias (precursor B-ALL), 74 Iglambda+ chronic B cell leukemias (CBL), 34 Iglambda+ non-Hodgkin lymphomas (B-NHL), and 28 Iglambda+ multiple myelomas (MM). The J-Clambda3 gene region was most frequently involved (50%), followed by J-Clambda2 (38%) and J-Clambda1 (9%). There was no involvement of the J-Clambda4 and J-Clambda5 gene regions. Rearrangements to J-Clambda6 (n= 4) were exclusively found in precursor B-ALL (19% of all IGL rearrangements in precursor B-ALL) and only a single J-Clambda7 recombination was detected in an Iglambda+ B-NHL. In the group of Iglambda+ malignancies, a significant shift was observed from predominant J-Clambda3 usage (54%) in mature surface Iglambda+ malignancies (CBL and B-NHL) to 60% J-Clambda2 usage in Iglambda+ secreting MM. The distribution of IGL isotype rearrangements found in MM resembled the Iglambda isotype protein expression reported in MM patients. Based on these extensive Southern blot data, we suggest that a rapid and efficient detection of clonal IGL gene rearrangements can be obtained when a single Bg/II digest is used in combination with the IGLJ2 probe, which detects clonality in >95% of cases with an Iglambda+ malignancy. Higher percentages (>98%) can be reached by including a second digest (HindIII) that reduces the chance of comigration of rearranged and germline bands. In case of precursor B-ALL we recommend including the IGLJ6 probe for the detection of rearrangements to J-Clambda6.

Gene Rearrangement, B-Lymphocyte, Light Chain↗
PubMed2001

BIOMED-I concerted action report: flow cytometric immunophenotyping of precursor B-ALL with standardized triple-stainings. BIOMED-1 Concerted Action Investigation of Minimal Residual Disease in Acute Leukemia: International Standardization and Clinical Evaluation.

The flow cytometric detection of minimal residual disease (MRD) in precursor-B-acute lymphoblastic leukemias (precursor-B-ALL) mainly relies on the identification of minor leukemic cell populations that can be discriminated from their normal counterparts on the basis of phenotypic aberrancies observed at diagnosis. This technique is not very complex, but discordancies are frequently observed between laboratories, due to the lack of standardized methodological procedures and technical conditions. To develop standardized flow cytometric techniques for MRD detection, a European BIOMED-1 Concerted Action was initiated with the participation of laboratories from six different countries. The goal of this concerted action was to define aberrant phenotypic profiles in a series of 264 consecutive de novo precursor-B-ALL cases, systematically studied with one to five triple-labelings (TdT/CD10/CD19, CD10/CD20/CD19, CD34/CD38/CD19, CD34/CD22/CD19 and CD19/CD34/CD45) using common flow cytometric protocols in all participating laboratories. The use of four or five triple-stainings allowed the identification of aberrant phenotypes in virtually all cases tested (127 out of 130, 98%). These phenotypic aberrancies could be identified in at least two and often three triple-labelings per case. When the analysis was based on two or three triple-stainings, lower incidences of aberrancies were identified (75% and 81% of cases, respectively) that could be detected in one and sometimes two triple-stainings per case. The most informative triple staining was the TdT/CD10/CD19 combination, which enabled the identification of aberrancies in 78% of cases. The frequencies of phenotypic aberrations detected with the other four triple-stainings were 64% for CD10/CD20/CD19, 56% for CD34/CD38/CD19, 46% for CD34/CD22/CD19, and 22% for CD19/CD34/CD45. In addition, cross-lineage antigen expression was detected in 45% of cases, mainly coexpression of the myeloid antigens CD13 and/or CD33 (40%). Parallel flow cytometric studies in different laboratories finally resulted in highly concordant results (>90%) for all five antibody combinations, indicating the high reproducibility of our approach. In conclusion, the technique presented here with triple-labelings forms an excellent basis for standardized flow cytometric MRD studies in multicenter international treatment protocols for precursor-B-ALL patients.

Antigens, CD↗
PubMed2001

Precursor-B-ALL with D(H)-J(H) gene rearrangements have an immature immunogenotype with a high frequency of oligoclonality and hyperdiploidy of chromosome 14.

The IGH gene configuration was investigated in 97 childhood precursor-B-ALL patients at initial diagnosis. Rearrangements were found by Southern blotting in all but three patients (97%) and in 30 cases (31%) we observed oligoclonal IGH gene rearrangements. Heteroduplex PCR analysis revealed at least one clonal PCR product in all Southern blot-positive cases. In 89 patients (92%) complete V(D)J rearrangements were found, while incomplete D(H)-J(H) rearrangements occurred in only 21 patients (22%). In 5% of cases the D(H)-J(H) rearrangements were the sole IGH gene rearrangements. Sequence analysis of the 31 identified incomplete rearrangements revealed preferential usage of segments from the D(H)2, D(H)3 and D(H)7 families (78%). While D(H)2 and D(H)3 gene rearrangements occur frequently in normal B cells and B cell precursors, the relatively frequent usage of D(H)7-27 (19%) in precursor-B-ALL patients is suggestive of leukemic transformation during prenatal lymphopoiesis. Among J(H) gene segments in the incomplete D(H)-J(H) rearrangements, the J(H)6 segment was significantly overrepresented (61%). This observation together with the predominant usage of the most upstream D(H) genes indicates that many of the identified clonal D(H)-J(H) gene rearrangements in precursor-B-ALL probably represent secondary recombinations, having deleted pre-existing D(H)-J(H) joinings. The patients with incomplete D(H)-J(H) gene rearrangements were frequently characterized by hyperdiploid karyotype with additional copies of chromosome 14 and/or by IGH oligoclonality. The presence of incomplete D(H)-J(H) joinings was also significantly associated with a less mature immunogenotype: overrepresentation of V(H)6-1 gene segment usage, absence of biallelic TCRD deletions, and low frequency of TCRG gene rearrangements. This immature immunogenotype of precursor-B-ALL with incomplete IGH gene rearrangements was not associated with more aggressive disease.

Adolescent↗
PubMed2001

Two consecutive immunophenotypic switches in a child with immunogenotypically stable acute leukaemia.

A 12-year-old girl presented with a CD33+ precursor B-acute lymphoblastic leukaemia (ALL) and seemed to respond well to ALL treatment. However, 2 weeks after diagnosis her leucocyte count rose rapidly with a predominance of myeloid blasts with M5b morphology and CD19+ myeloid immunophenotype. Acute myeloid leukaemia (AML) treatment was started and remission was achieved after one course of chemotherapy; the AML treatment was continued for 6 months. Two months after cessation of chemotherapy, the patient developed a bone marrow relapse, this time with an undifferentiated blast morphology and a precursor B immunophenotype. Molecular analysis of the immunoglobulin and T-cell receptor genes showed several clonal gene rearrangements at diagnosis: two IGH, two IGK and two TCRD gene rearrangements. All rearrangements were also detected during the AML phase of the disease, suggesting a phenotypic shift of the same leukaemia. At relapse, 8 months later, all rearrangements were preserved except for one TCRD (Vdelta2-Ddelta3) rearrangement. The first phenotypic shift in the genotypically stable leukaemia was remarkably fast. The most probable explanation for our observations is an oncogenic event in an undifferentiated haematopoietic progenitor clone, with a highly versatile phenotype.

Acute Disease↗