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Anton Hagenbeek

Publications and source records attributed to Anton Hagenbeek.

At least 19 recordsLinked to original sources

Quantitative assessment of human T lymphocytes in RAG2(-/-)gammac(-/-) mice: the impact of ex vivo manipulation on in vivo functionality.

OBJECTIVE: Recent clinical trials of adoptive immunotherapy showed diminished reactivity of human T cells upon ex vivo manipulation. For a safe and effective clinical application of human T cells, it is necessary to improve ex vivo manipulation procedures and evaluate their impact on in vivo functionality. However, there is no preclinical model for quantitative assessment of in vivo functionality of human T cells. In this study, we investigated the feasibility of using the huPBMC- RAG2(-/-)gammac(-/-) xenogeneic mouse model. As a first example, we compared 3 different ex vivo culture conditions for human T cells. METHODS: RAG2(-/-)gammac(-/-) mice received cultured human T cells that were stimulated via CD3 alone or costimulated via CD28 (CD3/28) and/or human 4-1BB (CD3/28/4-1BB). Engraftment levels and survival of the cells were measured. The dynamics of the human T cell phenotypes were analyzed during culture and in vivo, as well as the mechanism of the xenoresponse. RESULTS: Engraftment potential was improved twofold for costimulation compared to CD3 alone (p < 0.001). Phenotypic analysis showed a strikingly similar pattern of development towards CD4(+) and CD8(+) effector and effector-memory cells, suggesting antigen-driven survival and expansion. All parameters used to analyze different effects on in vivo T-cell functionality, like culture condition, engraftment levels, survival of the cells over time, or xenogeneic graft-vs-host disease were absolutely independent of the distribution of the T cell population in vivo following contact with xeno-antigen. CONCLUSION: The huPBMC-RAG2(-/-)gammac(-/-) xenogeneic transplant model is the most sensitive to date for in vivo functional evaluation of human T cells.

Animals↗

The therapeutic use of rituximab in non-Hodgkin's lymphoma.

The non-Hodgkin's lymphomas (NHLs) comprise a heterogeneous collection of lymphoproliferative malignancies, which are most common in people aged over 55 years. Diffuse large B-cell lymphoma (DLBCL) is the most common type of NHL, accounting for approximately 30% of all new patients. Follicular lymphoma (FL) is the second most common NHL sub-type, and accounts for a further 22% of cases. While the incidence of most other cancers is decreasing, that of NHL is increasing steadily. During the 1970's and 1980's, worldwide NHL incidence rose by 3-4% per year. This rise has slowed in the 1990's, but an annual increase of 1-2% is still being recorded. Over the last five years, the introduction of monoclonal antibodies, and specifically the anti-CD20 monoclonal antibody, rituximab, has radically changed treatment of B-cell NHL. Rituximab is a genetically engineered chimeric mouse/human monoclonal antibody which binds to the transmembrane antigen, CD20, a non-glycosylated phosphoprotein, located on pre-B and mature B lymphocytes. This antigen is expressed on over 95% of all B cell NHLs, and on normal B cells, but not on haematopoietic stem cells, normal or malignant plasma cells. The Fc domain of rituximab recruits immune effector functions to mediate B cell lysis. Possible mechanisms of cytotoxicity include complement-dependent cytotoxicity (CDC) resulting from C1q binding, and antibody-dependent cellular cytotoxicity (ADCC) mediated by one or more of the Fcgamma receptors on the surface of granulocytes, macrophages and NK cells. It is also possible that the binding of rituximab to the CD20 antigen on the cell surface may directly induce apoptosis. For patients with both follicular and diffuse large B-cell NHL, several large scale prospective randomised trials have demonstrated prolongation of remission when rituximab is incorporated into first line treatment, and, in follicular lymphoma, as a component of salvage therapy. As a result of these studies, current European indications for rituximab include: the treatment of previously untreated patients with stage III-IV follicular lymphoma in combination with cyclophosphamide, vincristine and prednisone (CVP) chemotherapy; as maintenance therapy in patients with relapsed follicular lymphoma responding to induction therapy with chemotherapy or immuno-chemotherapy; the treatment of patients with diffuse large B cell NHL in combination with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherapy. This paper examines the evidence supporting the use of rituximab in these settings, and places its use into the context of standard clinical practice.

Antibodies, Monoclonal↗

Rituximab maintenance improves clinical outcome of relapsed/resistant follicular non-Hodgkin lymphoma in patients both with and without rituximab during induction: results of a prospective randomized phase 3 intergroup trial.

We evaluated the role of rituximab (R) both in remission induction and maintenance treatment of relapsed/resistant follicular lymphoma (FL). A total of 465 patients were randomized to induction with 6 cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) (every 3 weeks) or R-CHOP (R: 375 mg/m(2) intravenously, day 1). Those in complete remission (CR) or partial remission (PR) were randomized to maintenance with R (375 mg/m(2) intravenously once every 3 months for a maximum of 2 years) or observation. R-CHOP induction yielded an increased overall response rate (CHOP, 72.3%; R-CHOP, 85.1%; P < .001) and CR rate (CHOP, 15.6%; R-CHOP, 29.5%; P < .001). Median progression-free survival (PFS) from first randomization was 20.2 months after CHOP versus 33.1 months after R-CHOP (hazard ratio [HR], 0.65; P < .001). Rituximab maintenance yielded a median PFS from second randomization of 51.5 months versus 14.9 months with observation (HR, 0.40; P < .001). Improved PFS was found both after induction with CHOP (HR, 0.30; P < .001) and R-CHOP (HR, 0.54; P = .004). R maintenance also improved overall survival from second randomization: 85% at 3 years versus 77% with observation (HR, 0.52; P = .011). This is the first trial showing that in relapsed/resistant FL rituximab maintenance considerably improves PFS not only after CHOP but also after R-CHOP induction.

Adult↗

Complement-induced cell death by rituximab depends on CD20 expression level and acts complementary to antibody-dependent cellular cytotoxicity.

PURPOSE: The use of the CD20-specific antibody rituximab has greatly improved the response to treatment of CD20+ follicular lymphoma. Despite the success of rituximab, resistance has been reported and prognostic markers to predict individual response are lacking. The level of CD20 expression on tumors has been related to response, but results of several studies are contradictory and no clear relationship could be established. Complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) are thought to be important effector mechanisms, but the exact mechanism of rituximab-mediated cell kill is still unknown. Importantly, no data have been reported on the combined contribution of CDC and ADCC. EXPERIMENTAL DESIGN: We have developed a system of clonally related CEM-CD20 cells by retroviral transfer of the human CD20 cDNA (n = 90). This set of cells, with the CD20 molecule as the only variable, was used to study the importance of CD20 expression level on rituximab-mediated CDC, ADCC, and the combination. RESULTS: We show a sigmoidal correlation of CD20 expression level and rituximab-mediated killing via CDC but not ADCC. On both high and low CD20-expressing cells, all CD20 molecules were translocated into lipid rafts after rituximab binding. Furthermore, CDC and ADCC act simultaneously and CDC-resistant cells are sensitive to ADCC and vice versa. CONCLUSIONS: These findings suggest that CDC depends on CD20 expression level and that both CDC and ADCC act complementary. These data give new insights into novel strategies to improve the efficacy of CD20-specific antibodies for the treatment of CD20+ tumors.

Antibodies, Monoclonal↗

Combined-modality therapy for clinical stage I or II Hodgkin's lymphoma: long-term results of the European Organisation for Research and Treatment of Cancer H7 randomized controlled trials.

PURPOSE: In early-stage Hodgkin's lymphoma (HL), subtotal nodal irradiation (STNI) and combined chemotherapy/radiotherapy produce high disease control rates but also considerable late toxicity. The aim of this study was to reduce this toxicity using a combination of low-intensity chemotherapy and involved-field radiotherapy (IF-RT) without jeopardizing disease control. PATIENTS AND METHODS: Patients with stage I or II HL were stratified into two groups, favorable and unfavorable, based on the following four prognostic factors: age, symptoms, number of involved areas, and mediastinal-thoracic ratio. The experimental therapy consisted of six cycles of epirubicin, bleomycin, vinblastine, and prednisone (EBVP) followed by IF-RT. It was randomly compared, in favorable patients, to STNI and, in unfavorable patients, to six cycles of mechlorethamine, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine (MOPP/ABV hybrid) and IF-RT. RESULTS: Median follow-up time of the 722 patients included was 9 years. In 333 favorable patients, the 10-year event-free survival rates (EFS) were 88% in the EBVP arm and 78% in the STNI arm (P = .0113), with similar 10-year overall survival (OS) rates (92% v 92%, respectively; P = .79). In 389 unfavorable patients, the 10-year EFS rate was 88% in the MOPP/ABV arm compared with 68% in the EBVP arm (P < .001), leading to 10-year OS rates of 87% and 79%, respectively (P = .0175). CONCLUSION: A treatment strategy for early-stage HL based on prognostic factors leads to high OS rates in both favorable and unfavorable patients. In favorable patients, the combination of EBVP and IF-RT can replace STNI as standard treatment. In unfavorable patients, EBVP is significantly less efficient than MOPP/ABV.

Adolescent↗

Phase III intergroup study of fludarabine phosphate compared with cyclophosphamide, vincristine, and prednisone chemotherapy in newly diagnosed patients with stage III and IV low-grade malignant Non-Hodgkin's lymphoma.

PURPOSE: To compare the efficacy and safety of fludarabine phosphate with cyclophosphamide, vincristine, and prednisone (CVP) in 381 previously untreated, advanced-stage, low-grade (lg) non-Hodgkin's lymphoma (NHL) patients in a phase III, multicenter study. PATIENTS AND METHODS: Between 1993 and 1997, patients were randomly assigned to treatment with either fludarabine (25 mg/m2 intravenously [IV] daily for 5 days every 4 weeks) or CVP (cyclophosphamide 750 mg/m2 IV on day 1; vincristine, 1.4 mg/m2 IV on day 1; and prednisone, 40 mg/m2 orally on days 1 through 5 every 4 weeks). Results Overall response (OR) rates were significantly improved in the fludarabine arm versus the CVP arm, both for the intent-to-treat (ITT) population and assessable patients (P < .001). Complete response (CR) rates in the ITT population were also higher after fludarabine treatment. The CR rate was 38.6% for fludarabine compared with 15.0% for CVP. There were no statistically significant differences in time to progression (TTP), time to treatment failure (TTF), and overall survival (OS) between treatment groups. WHO grades 3 and 4 hematologic adverse events were more common in the fludarabine arm. However, concerning the higher incidence of granulocytopenia, this did not translate to more infections in fludarabine-treated patients. CONCLUSION: Newly diagnosed lgNHL patients who received fludarabine achieved higher OR and CR rates compared with CVP-treated patients. No differences in TTP, TTF, and OS were noted. Fludarabine is a highly active single agent in lgNHL. Combination therapies incorporating fludarabine are now being further evaluated as first-line therapy in follicular NHL.

Adult↗

Identification of a 40S ribosomal protein S4-derived H-Y epitope able to elicit a lymphoblast-specific cytotoxic T lymphocyte response.

PURPOSE: The superior graft-versus-leukemia (GVL) effect of the female-to-male stem cell transplantation is partially independent from the concomitant graft-versus-host reactivity. However, the antigenic basis of this selective GVL response remains enigmatic, because no H-Y antigens with hematopoietic-restricted expression were identified. In this study, we report a novel H-Y epitope that is preferentially recognized on activated proliferating lymphocytes. EXPERIMENTAL DESIGN: We generated a CTL clone YKIII.8 that showed reactivity toward male B*5201+ CD40-activated B cells, EBV-lymphoblastoid cell lines, and phytohemagglutinin-activated T-cell blasts but little or no reactivity toward fibroblasts, CD14+ cells, or unstimulated B and T cells. The antigen recognized by YKIII.8 was identified by screening of a cDNA expression library, and its pattern of expression was investigated. RESULTS: cDNA of the male isoform of 40S ribosomal protein S4 was found to encode the antigenic peptide TIRYPDPVI, which was recognized by YKIII.8. Western blot analysis showed that rapidly proliferating cells overexpress the RPS4 protein in comparison with nonrecognized cell subsets. Retroviral transfer of YKIII.8 T-cell receptor resulted in preservation of the lymphoblast-specific reactivity pattern. CONCLUSION: Our findings suggest that CTL specific to certain epitopes of ubiquitously expressed H-Y antigens may specifically target lymphoblasts, contributing to the selective GVL effect of female-to-male stem cell transplantation.

Blotting, Western↗

Future trends in radioimmunotherapy.

Radioimmunotherapy (RIT) is currently approved in the United States only for use in low-grade follicular or transformed non-Hodgkin's lymphoma. One of the major issues in the construction of new clinical trials is deciding in which phase of disease RIT should be applied: upfront, as part of first-line treatment, in relapsed/refractory patients, in bulky or 'minimal residual disease', or in patients failing 'cold' antibody treatment? An important consideration for future trends in RIT is how the efficacy of RIT can be increased, while limiting toxicity. To increase efficacy, it is important to understand the reasons why RIT can fail in some patients. Efficacy might be increased by improving tumor to normal organ ratios of antibody (using synthetic clearing agents to clear nontumor-bound antibody from the bloodstream), or by combining RIT with radiosensitizers, such as fludarabine. Methods of reducing toxicity are also being investigated (eg, by splitting the full dose of RIT, or using biological prognostic factors to identify patients who are likely to experience myelosuppression). Biological prognostic factors may also predict disease response and can be used to stratify patients into risk groups at diagnosis, which may predict outcome according to a limited set of prognostic factors. It is also important to establish the effect of prior chemotherapy regimens on RIT, and likewise to determine to what extent RIT compromises subsequent chemotherapy treatment. This article attempts to address these issues and anticipate future trends in RIT.

Antineoplastic Agents↗

UTY-specific TCR-transfer generates potential graft-versus-leukaemia effector T cells.

Immunotherapeutic approaches that target antigens that are differentially recognized on haematopoietic and non-haematopoietic cells may specifically enhance the graft-versus-leukaemia (GVL) effect of donor lymphocyte infusion. In this study, we have characterized a new HLA-B*5201-restricted epitope of the UTY gene. Unusually, presentation of this epitope was restricted to lymphoblasts. As a result, a T cell clone specific to this epitope recognized normal and malignant male B and T lymphoblasts, while showing little reactivity towards male HLA-B*5201+ fibroblasts. Transfer of its T cell receptor (TCR) into donor T cells led to the generation of large numbers of T cells, which acquired the specificity of the original clone, its avidity and the differential pattern of reactivity towards lymphoblasts and fibroblasts. Remarkably, the specific response of TCR-transferred T cells was significantly higher than that of the original clone. This is the first demonstration of the possibility to preserve the specific pattern of a T cell response to a differentially expressed antigen after TCR-transfer and to augment the amplitude of this response concomitantly. These results indicate that it may be feasible to enhance the GVL effect of donor lymphocyte infusions in lymphoproliferative malignancies by the transfer of TCRs specific to epitopes that are differentially recognized on lymphoblasts.

Cell Culture Techniques↗

Cost analysis of common treatment options for indolent follicular non-Hodgkin's lymphoma.

BACKGROUND AND OBJECTIVES: We assessed direct health care costs associated with the most commonly prescribed treatments for indolent follicular non-Hodgkin's lymphoma (FL). DESIGN AND METHODS: New and previously diagnosed FL patients (>or=18 years) known during 1997-1998 to 15 Dutch hospitals were selected for inclusion. Each patient was followed for 3 years, and resource use associated with each of the treatments, including watchful waiting, was recorded. The hospital perspective was adopted. Unit costs were based on 2003 price levels. RESULTS: Two hundred patients were included of whom 75% underwent one or more treatments during the 3-year data collection period [25% were not treated because of a watchful waiting strategy (10%) or complete remission (15%)]. Allogeneic and autologous stem cell transplantations were the most expensive treatments, with a mean (median) per patient cost of 45,326 euro(44,237; n=7) and 18,866 euro (16,532; n=9), respectively (up to discharge only). Intravenous fludarabine cost 10,651 euro (9,995; n=33), rituximab (10,628 euro; 10,124; n=7), and CHOP 7,547 euro (5,833; n=42). Classical FL treatments were found to be the least expensive treatments used with an estimated cost for cylophosphamide, vincristine and prednisone of 5,268 euro (2,644; n=58), for radiotherapy of 4,218 euro (4,313; n=52), and for chlorambucil of 2,476 euro (1,098; n=53). INTERPRETATION AND CONCLUSIONS: This study presents information on resource use and costs associated with the most commonly prescribed FL treatments. In addition to differences in effectiveness, commonly used treatments vary considerably in terms of resource use and overall cost. This information is of value for resource planning, given the high costs of new treatment modalities.

Adult↗

Follicular lymphoma international prognostic index.

The prognosis of follicular lymphomas (FL) is heterogeneous and numerous treatments may be proposed. A validated prognostic index (PI) would help in evaluating and choosing these treatments. Characteristics at diagnosis were collected from 4167 patients with FL diagnosed between 1985 and 1992. Univariate and multivariate analyses were used to propose a PI. This index was then tested on 919 patients. Five adverse prognostic factors were selected: age (> 60 years vs < or = 60 years), Ann Arbor stage (III-IV vs I-II), hemoglobin level (< 120 g/L vs > or = 120 g/L), number of nodal areas (> 4 vs < or = 4), and serum LDH level (above normal vs normal or below). Three risk groups were defined: low risk (0-1 adverse factor, 36% of patients), intermediate risk (2 factors, 37% of patients, hazard ratio [HR] of 2.3), and poor risk (> or = 3 adverse factors, 27% of patients, HR = 4.3). This Follicular Lymphoma International Prognostic Index (FLIPI) appeared more discriminant than the International Prognostic Index proposed for aggressive non-Hodgkin lymphomas. Results were very similar in the confirmation group. The FLIPI may be used for improving treatment choices, comparing clinical trials, and designing studies to evaluate new treatments.

Adult↗

Ganciclovir-mediated elimination of HSV-Tk+ T cells and cure of graft-vs-host disease in an allogeneic bone marrow transplantation model in the rat.

OBJECTIVE: Suicide gene therapy for leukemia aims to benefit from T cells in the BM graft, by reducing the probability of leukemia relapse (GVL), while severe complications of graft-vs-host disease (GVHD) may be avoided. In an allogeneic rat BMT model we defined the conditions to induce a lethal GVHD with HSV-Tk gene-transduced T cells. We studied the feasibility to rescue the animals by conditional elimination of the T cells with ganciclovir (GCV) treatment. METHODS: Allogeneic T cells transduced with a retroviral vector encoding the HSV-Tk suicide gene were added in varying numbers to a BM graft. Expression of HSV-Tk strongly increases the cytolytic effect of GCV, thereby allowing elimination of overreactive T cells at will. Various experimental conditions were tested in the rat model. RESULTS: A relation between the number of HSV-Tk(+) T cells added to the BM graft and GVHD development was found. GCV treatment resulted in selective HSV-Tk(+) T-cell elimination in blood and tissues but not in abrogation of GVHD due to persistence of HSV-Tk(-) T cells. T cells in unmanipulated rat BM normally have a low risk to induce GVH but when they are administered in combination with high numbers of HSV-Tk(+) T cells there is an apparent increase in their GVH-inducing potential. When HSV-Tk(+) T cells are added to T cell-depleted BM a consequently developing GVH can be controlled by GCV treatment with 60-70% of the animals surviving. CONCLUSIONS: We show that T cell-mediated suicide gene therapy within the context of allo-BMT can be applied with success. The apparent limitation in the number of transduced as well as nontransduced T cells that can be safely added to the BM graft should be taken into consideration when designing human suicide gene therapy protocols.

Animals↗

Enhanced engraftment of human cells in RAG2/gammac double-knockout mice after treatment with CL2MDP liposomes.

OBJECTIVE: The ability of human cells to repopulate the bone marrow of nonobese diabetic immunodeficient mice (NOD/SCID) is commonly used as a standard assay to quantify the primitive human hematopoietic stem cell population. We studied the applicability of the immunodeficient RAG2(-/-)gammac(-/-) double-knockout mouse for this purpose. METHODS: RAG2(-/-)gammac(-/-) mice and NOD/SCID mice were injected intravenously (i.v.) with umbilical cord blood-derived CD34(+) cells and engraftment was quantified by determining the human CD45+ cell chimerism in bone marrow at several time points. RAG2(-/-)gammac(-/-) were pretreated with total-body irradiation and depleted of macrophages in liver, spleen, and bone marrow by i.v. injection of clodronate diphosphonate containing liposomes. RESULTS: We demonstrated that the frequency of chimerism and the level of engraftment in macrophage-depleted RAG2(-/-)gammac(-/-) largely resemble that in NOD/SCID mice. Also similar is the multilineage differentiation pattern in the two mouse strains at 7 weeks after transplantation, with a prominent outgrowth in RAG2(-/-)gammac(-/-) of CD19+ cells (88% +/- 10%). Cells of other lineages were clearly less frequent: 9% +/- 2% myeloid cells and 0.1% +/- 0.1% erythroid cells. As for immature progenitors, 6% +/- 1% of the human cells express the CD34 antigen and 0.4% +/- 0.1% have the CD34+,CD33,38,71(-) phenotype. The presence of human committed progenitors (i.e., CFU-GM/BFU-E) was evident. The persistence of human cells at 4 months after transplantation shows that the RAG2(-/-)gammac(-/-) support long-term maintenance of human hematopoiesis. CONCLUSION: Our findings indicate that macrophage-depleted RAG2(-/-)gammac(-/-) are a suitable model for studying human hematopoiesis including multipotential stem cells, and long-term repopulation.

Animals↗

Economic assessment in the management of non-Hodgkin's lymphoma.

An increasing need for economic evaluations of non-Hodgkin's lymphoma (NHL) treatments exists. We performed a literature review on the currently available NHL economic evaluations, using PubMed and the Cochrane database. English and Dutch language papers on treatment in adults were selected. A total of 88 publications were found, 44 of which were included. Of these, 6 economic evaluation-specific methodological items are evaluated (study perspective, overhead costs, data sources, charges or prices, sensitivity analysis, presentations of resource use and unit costs), enabling readers to judge the value of these studies. The 11 subjects covered by the economic evaluations are discussed. Many NHL treatments remain to be studied in economic evaluations. Future publications should report on the six methodological items in more detail, and preferably tackle them in the recommended way.

Adult↗

Involved-field radiotherapy for advanced Hodgkin's lymphoma.

BACKGROUND: The use of involved-field radiotherapy after chemotherapy for advanced Hodgkin's lymphoma is controversial. METHODS: We randomly assigned patients with previously untreated stage III or IV Hodgkin's lymphoma who were in complete remission after hybrid chemotherapy with mechlorethamine, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine (MOPP-ABV) to receive either no further treatment or involved-field radiotherapy. Radiotherapy consisted of 24 Gy to all initially involved nodal areas and 16 to 24 Gy to all initially involved extranodal sites. Patients in partial remission were treated with 30 Gy to nodal areas and 18 to 24 Gy to extranodal sites. RESULTS: Of 739 patients, 421 had a complete remission; 161 of these patients were assigned to no further treatment, and 172 to involved-field radiotherapy. The median follow-up was 79 months. The five-year event-free survival rate was 84 percent in the group that did not receive radiotherapy and 79 percent in the group that received involved-field radiotherapy (P=0.35). The five-year overall survival rates were 91 and 85 percent, respectively (P=0.07). Among the 250 patients in partial remission after chemotherapy, the five-year event-free and overall survival rates were 79 and 87 percent, respectively. CONCLUSIONS: Involved-field radiotherapy did not improve the outcome in patients with advanced-stage Hodgkin's lymphoma who had a complete remission after MOPP-ABV chemotherapy. Radiotherapy may benefit patients with a partial response after chemotherapy.

Adolescent↗

A new xenograft model for graft-versus-host disease by intravenous transfer of human peripheral blood mononuclear cells in RAG2-/- gammac-/- double-mutant mice.

The safe application of new strategies for the treatment of graft-versus-host disease (GVHD) is hampered by the lack of a clinically relevant model for preclinical testing. Current models are based on intraperitoneal transfer of human peripheral blood mononuclear cells (huPBMCs) into NOD-SCID (nonobese diabetic-severe combined immunodeficient)/SCID mice. Intravenous transfer would be preferred but this has always been ineffective. We developed a new model for xenogeneic GVHD (X-GVHD) by intravenous transfer of huPBMCs into RAG2-/- gammac-/-mice. Our results show a high human T-cell chimerism of more than 20% (up to 98%) in more than 90% of mice, associated with a consistent development of XGVHD within 14 to 28 days and a total mortality rate of 85% shorter than 2 months. After murine macrophage depletion, engraftment was earlier and equally high with lower doses of huPBMCs. Human macrophages were also absent in these mice. Purified huCD3+ cells showed a similar X-GVH effect with contribution of both CD4 and CD8 phenotypes. Human immunoglobulins and cytokines were produced in diseased mice. One of 30 mice developed chronic X-GVHD with skin histology similar to human GVHD. In conclusion, we present a new model for X-GVHD by intravenous transfer of huPBMCs in RAG2-/- gammac-/- mice. Murine and human macrophages do not seem to be necessary for acute X-GVHD in this model.

Animals↗