The impact of chemotherapy-induced side effects on medical care usage and cost in German hospital care--an observational analysis on non-small-cell lung cancer patients.

PURPOSE: To evaluate frequency and severity of adverse drug reactions (ADRs) and its economic consequences after standard dose (immuno-)chemotherapy (CT) of non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Subanalysis of a prospective, multicentre, longitudinal, observational cohort study; data were collected from patient interviews and pre-planned chart reviews. Costs were aggregated per CT line and presented from provider perspective. RESULTS: A total of 120 consecutive NSCLC patients (mean age, 63.0 ± 8.4 (SD) years; men, 64.2%; ECOG (Eastern Cooperative Oncology Group) performance status <2, 84.3%; tumour stage III/IV, 85%; history of comorbidity, 93.3%) receiving 130 CT lines were evaluated. 80% of CT lines were associated with grade 3 or 4 ADRs, 22.3% developed potential life-threatening complications, 77.7% were associated with at least one hospital stay (inpatient, 63.9%; outpatient/day clinic 39.2%, ICU 6.9%), with a mean cumulative number of 12.8 (±14.0 SD) hospital days. Mean (median) toxicity management costs per CT line (TMC-TL) amounted to €3,366 (€1,406) and were found to be higher for first-line compared to second-line treatment: €3,677 (€1,599) vs. €2,475 (€518). TMC-TL were particularly high in CT lines with ICU care €12,207 (€9,960). Eight out of 11 ICU stays were associated with grade 3 or 4 infections. Nine CT lines with ICU care accounted for 25% of total expenses (€109,861 out of €437,580). CONCLUSIONS: In first-line NSCLC treatment, in particular, CT toxicity management is expensive. Asymmetric cost distribution seems to be triggered by infection associated ICU care. Its avoidance should reduce patients' clinical burden and have considerable economic implications. Nevertheless, comparative observational studies have to confirm estimated savings.

Health resource consumption and costs attributable to chemotherapy-induced toxicity in German routine hospital care in lymphoproliferative disorder and NSCLC patients.

BACKGROUND: Multidrug chemotherapy (CT) is still associated with relevant side-effects. We assessed, under current practice patterns, frequency and severity of CT-induced toxicity and its economic consequences. PATIENTS AND METHODS: Prospective, multicentre, longitudinal, observational cohort study with lymphoproliferative disorder (LPD) and non-small-cell lung cancer (NSCLC) patients, receiving first- or second-line (immuno-) CT (excluding myeloablative CT). Data were collected from patient interviews and preplanned chart reviews. Costs in 2007 euros are presented from the provider perspective. RESULTS: Two hundred and seventy-three patients (n = 153 LPD; n = 120 NSCLC) undergoing a total of 1004 CT cycles were assessable (age ≥65 years, 40%; female, 36%; Eastern Cooperative Oncology Group performance status ≥2, 11%; tumour stage ≥III, 56%; history of comorbidity, 80%). Fifty percent of cycles were associated with grade 3/4 toxicity and 37% (n = 371) with at least one hospital stay (outpatient/day care n = 154; intensive care n = 19). Mean (median) toxicity-related costs amounted to €1032 (€86) per cycle. Costs rose exponentially with the number of grade 3/4 adverse drug reactions (ADRs) and were highest in cycles affected by more than four ADRs, €10 881 (€5455); in cycles with intensive care, €14 121 (€8833); and in cycles affected by grade 3/4 infections and febrile neutropenia/leukopenia, €7093 (€4531) and €5170 (€2899), respectively. Five percent of CT cycles accounted for 56% of total expenses. CONCLUSIONS: Individualised supportive care strategies are needed. Future research should focus on identifying toxicity clusters and patient characteristics predictive for high costs.

[Guideline for radioimmunotherapy of CD20+ follicular B-cell non-Hodgkin's lymphoma]. / Leitlinie für die Radioimmuntherapie des CD20-positiven follikulären B-Zell-Non-Hodgkin-Lymphoms.

This guideline is a prerequisite for the quality management in the treatment of non-Hodgkon-lymphomas in patients with relapsed or refractory follicular lymphoma after rituximab therapy and as consolidation therapy after first remission following CHOP like treatment using radioimmunotherapy. It is based on an interdisciplinary consensus and contains background information and definitions as well as specified indications and detailed contraindications of treatment. Essential topics are the requirements for institutions performing the therapy. For instance, presence of an expert for medical physics, intense cooperation with all colleagues committed to treatment of lymphomas, and a certificate of instruction in radiochemical labelling and quality control are required. Furthermore, it is specified which patient data have to be available prior to performance of therapy and how treatment has to be carried out technically. Here, quality control and documentation of labelling are of great importance. After treatment, clinical quality control is mandatory (work-up of therapy data and follow-up of patients). Essential elements of follow-up are specified in detail. The complete treatment inclusive after-care has to be realised in close cooperation with those colleagues (hemato-oncologists) who propose, in general, radioimmunotherapy under consideration of the development of the disease.

Results of a national consensus workshop: therapeutic algorithm in patients with follicular lymphoma--role of radioimmunotherapy.

Radioimmunotherapy (RIT) was approved for the treatment of relapsed or refractory CD20-positive follicular lymphoma (FL), subsequent to rituximab containing primary therapy. However, an increasing number of clinical studies have suggested that RIT may be more efficacious in an earlier phase of the disease. Therefore, a consensus meeting was held in May 2005 to define the optimal setting of RIT in the therapeutic algorithm of patients with advanced stage of FL. RIT is an established therapeutic option in relapsed FL. According to the reviewed data, RIT should be preferably used as consolidation after initial tumor debulking. First-line RIT may be applied in patients not appropriate for chemotherapy induction. Current study concepts evaluate the role of RIT consolidation in combination with antibody maintenance to achieve a potentially curative approach even in patients with advanced stage disease.

Increased IkappaB kinase activity is associated with activated NF-kappaB in acute myeloid blasts.

NF-kappaB/Rel transcription factors are modulators of immune and inflammatory processes and are also involved in malignancy. Phosphorylation of the IkappaB inhibitors by the IkappaB kinase (IKK) complex leads to their proteasomal degradation, resulting in activated NF-kappaB. Here, we investigated the activation status of NF-kappaB and the IKK complex in acute myeloid leukemia (AML). Gelshift assays revealed an increased level of activated nuclear NF-kappaB in myeloid blasts. Both bone marrow and peripheral blood blasts from AML patients showed enhanced IKK activity relative to controls, whereas the IKK protein concentrations were comparable. In addition, an increased level of IkappaB-alpha was detected in AML blast cells, although this appeared to be insufficient to block nuclear translocation of NF-kappaB, also confirmed by immunofluorescence. In subtype M4 and M5 AML cells a more extensive NF-kappaB activation and higher IKK activity was found than in M1/M2 specimens. Isolated AML blasts cultured ex vivo responded to external stimulation (TNF, LPS) by further IKK activation, IkappaB degradation and NF-kappaB activation. Preincubation with the proteasome inhibitor PSI inhibited the NF-kappaB system in isolated AML blasts. This study established for the first time a dysregulation of IKK signaling in AML leading to increased NF-kappaB activity suggesting potential therapeutic avenues.

Dose-intensified treatment of breast cancer: current results.

Chemotherapy has an established role in the treatment of carcinoma of the mammary gland (breast cancer), but when administered at conventional doses the net benefit in terms of relapse prevention and overall survival duration remains limited largely to operable patients at first diagnosis with limited tumor burden (stage II disease with less than four involved axillary lymph nodes). Pilot studies evaluating significant dose escalation in patients with advanced disease have yielded high remission rates, but the impact on long-term survival remains controversial. Recent trials involving dose-intense treatment in stage IV breast cancer do not support its use except in patients who have achieved complete remission or show no evidence of disease prior to high-dose consolidation. More optimism may be warranted for the use of dose-intense chemotherapy in the high-risk adjuvant setting (stage II/IIIA) and as part of the initial treatment for patients with inflammatory breast cancer or locally advanced primary inoperable carcinoma (stage IIIB). Prospective randomized trials in all settings are ongoing, although definitive results are not expected before 1998. Apart from single-course myeloablative high-dose chemotherapy, the availability of hematopoietic growth factors through recombinant DNA technology and the easy procurement of hematopoietic cell support through mobilization of peripheral blood progenitors has spurred the development of new strategies employing dose-intense treatment within the past 10 years. Repetitive application of chemotherapy at submyeloablative doses and sequential accelerated dose-intense application of single agents are now increasingly being integrated into more complex dose-escalated protocols. This review will focus on the results of mature trials and newer approaches to dose escalation.

Splenic marginal zone lymphocytes and related cells in the lymph node: a morphologic and immunohistochemical study.

The marginal zone of the spleen contains a well-defined population of lymphocytes with an unknown function. The question is whether this cell population is unique to the spleen or is it also present in the lymph node. These cells have medium-sized nuclei and a moderate amount of cytoplasm. Immunohistochemistry and enzyme histochemistry revealed a marker pattern by which these cells could be distinguished from the lymphocytes of the mantle zone of the spleen: IgD-, CD23-, KiB3-, and alkaline phosphatase+. In the lymph node, the outer side of the follicular mantle contains a subpopulation of B lymphocytes with a similar morphology and the same marker pattern. This subpopulation differs from the marginal zone cells in the spleen in that it does not form a distinct zone. These cells are especially prominent in lymph nodes with fatty atrophy. Their relationship to other subpopulations of B lymphocytes and to malignant lymphomas is evaluated but remains questionable.

Fibroblasts retrovirally transfected with the human IL-3 gene initiate and sustain multilineage human hematopoiesis in SCID mice: comparison of CD34-enriched vs CD34-enriched and in vitro expanded grafts.

Peripheral blood progenitor cells (PBPCs) obtained from cytapheresis products (CPs) of tumor patients undergoing mobilizing chemotherapy for PBPC support and dose-intensified anticancer chemotherapy initiate multilineage human hematopoiesis after intraperitoneal (i.p.) transplantation into young severe combined immunodeficient (SCID) mice. The engraftment process was significantly accelerated by subcutaneous cotransplants of a rat fibroblast cell line stably transfected with a retroviral vector carrying the human interleukin-3 (hIL-3) gene and producing sustained in vivo levels of circulating human IL-3 over a prolonged period of time. These cotransplants were found to provide a suitable microenvironment for i.p. transplanted CD34-positive cells separated from PBPC preparations using immunomagnetic beads. Flow cytometry analysis and immunocytology revealed that selected PB CD34- cells, more than 90% pure, were capable of initiating and sustaining a productive multilineage hematopoiesis preferentially within the hIL-3-secreting cotransplants followed by release of mature human cells into the circulation, spleen and thymus. The percentages of human cells found in hIL-3 cotransplants 8 weeks post-transplantation (p.t.) were generally higher than those measured after transplantation of complete CP mononuclear cells containing comparable doses of CD34-positive cells. When selected PB CD34+ cells that were expanded ex vivo with combinations of human hematopoietic growth factors including the c-kit ligand (KL), interleukin (IL)-1 beta, IL-3, IL-6, erythropoietin (EPO) and granulocyte-macrophage colony-stimulating factor (GM-CSF) for 14 days were grafted to cotransplant-carrying SCID mice, a considerable loss of their proliferative potential was observed regardless of the HGF combination used. When experiments with grafts of selected PBPC were compared to those performed with selected/expanded PBPC on a per CD34+ cell basis the results revealed that over a dose range of 0.3 to 1.0 x 10(6) cells/graft the in vivo proliferative capacity of expanded cells was reduced by a factor of 2 to 3.

[Guideline for radioimmunotherapy of rituximab relapsed or refractory CD20(+) follicular B-cell non-Hodgkin's lymphoma]. / Leitlinie für die Radioimmuntherapie des rezidivierenden oder refraktären CD20-positiven follikulären B-Zell-Non-Hodgkin-Lymphoms.

This guideline is a prerequisite for the quality management in the treatment of non-Hodgkin-lymphomas using radioimmunotherapy. It is based on an interdisciplinary consensus and contains background information and definitions as well as specified indications and detailed contraindications of treatment. Essential topics are the requirements for institutions performing the therapy. For instance, presence of an expert for medical physics, intense cooperation with all colleagues committed to treatment of lymphomas, and a certificate of instruction in radiochemical labelling and quality control are required. Furthermore, it is specified which patient data have to be available prior to performance of therapy and how the treatment has to be carried out technically. Here, quality control and documentation of labelling are of greatest importance. After treatment, clinical quality control is mandatory (work-up of therapy data and follow-up of patients). Essential elements of follow-up are specified in detail. The complete treatment inclusive after-care has to be realised in close cooperation with those colleagues (haematology-oncology) who propose, in general, radioimmunotherapy under consideration of the development of the disease.

Monocytoid B-cell lymphoma: morphological variants and relationship to low-grade B-cell lymphoma of the mucosa-associated lymphoid tissue.

Twenty-eight cases of monocytoid B-cell lymphoma of lymph nodes and 16 lymph node metastases of primary gastric lymphomas, mostly low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) type were investigated morphologically and immunohistochemically. Both groups showed the same morphological and immunohistochemical features: diagnostically important sites of infiltration were the sinuses and the marginal zones. The tumour cells were either medium-sized or small. The cytoplasm stained grey with Giemsa and was sometimes rather pale. In imprints the grey colour of the cytoplasm was a characteristic feature. The medium-sized cell type was more frequent; in one third of the cases it was combined with a prominent lymphoplasmacytic component from the same clone, and it resembled the monocytoid B-cells of the sinuses. The small cell type was less common, was not combined with a lymphoplasmacytic component and more closely resembled marginal zone cells. The difference was underlined by the negative reaction with the monoclonal antibody Ki-B3 in the small cell type, which, conversely, was positive in the medium-sized cell type and in the monocytoid B-cell reaction of the sinuses. Both of these cell types, however, showed a granular reaction with the new monoclonal antibody Ki-Mlp. The morphological and immunohistochemical parallels are arguments in favour of the assumption that monocytoid B-cell lymphoma is the nodal equivalent of low-grade B-cell lymphoma of MALT type. This is further supported by the fact that in nine of our 28 cases of monocytoid B-cell lymphoma, lymphomas were found simultaneously or subsequently in organs of the MALT. Monocytoid B-cell lymphoma must be differentiated from an infiltration that occurs in the form of clusters of monocytoid B-cells in other low-grade B-cell lymphomas, especially in immunocytoma with a high content of epithelioid cells.

Phase II trial of irinotecan plus docetaxel in cisplatin-pretreated relapsed or refractory oesophageal cancer.

This phase II trial assessed the toxicity and efficacy of irinotecan plus docetaxel in cisplatin-pretreated oesophageal cancer. Irinotecan 160 mg m(-2) plus docetaxel 65 mg m(-2) once every 3 weeks led to severe myelosuppression in four patients, all of whom experienced neutropenic fever. After amendment of this regimen, 24 patients (male/female=18/6; median age=58.5 years; ECOG performance status 0/1/2=9/11/4) with advanced oesophageal cancer (adenocarcinoma/epidermoid carcinoma=13/11) received irinotecan 55 mg m(-2) plus docetaxel 25 mg m(-2) on days 1, 8 and 15 of a 28-day cycle. Serious adverse events occurred in five patients, one with lethal outcome (pneumonia). Haematological toxicity >or=3 degrees was rare, whereas nonhaematological toxicity >or=3 degrees was noted in nine out of 24 patients (asthenia in five patients, diarrhoea in three patients, nausea/emesis in two patients, constipation in one patient). Median survival time was 26 (range 2-70) weeks. Response rate, assessed according to the WHO criteria, was 12.5% (95% CI 2.7-32.4%); rate of disease stabilisation (partial remission and stable disease) was 33.3% (95% CI 15.6-55.3%) with a median duration of 18.5 (range 16-51) weeks. Although the nonhaematological toxicity proved to be considerable, weekly irinotecan plus docetaxel is feasible and shows some activity in extensively pretreated patients with oesophageal cancer.

[Significance of serum beta-hCG as a tumor marker for stomach carcinoma]. / Zur Bedeutung von beta-hCG im Serum als Tumormarker für das Magenkarzinom.

INTRODUCTION: Recent investigations indicate that in 50% of patients with gastric cancer, beta-hCG-positive cells can be found in the tumour by immunohistochemical investigations. The objective of this study was to investigate how often beta-hCG-immunoreactive gastric carcinomas were accompanied by an elevation in serum beta-hCG, that could have been used as a course control variable. METHODS: In 54 patients with gastric carcinoma a monoclonal antibody directed against beta-hCG was used for immunohistochemical marking in the APAAP system. The evaluation was graded positive or negative. In parallel, serum beta-hCG was determined preoperatively using an enzyme immunoassay (MEIA). Tumour stage, grading and tumour localization were determinants in the evaluation. RESULTS: We found that 41% (22 of 54) of the carcinomas induced a positive immunohistochemical response to beta-hCG, regardless of their location in the stomach. In relation to tumour stage, a positive beta-hCG immunoreactivity was apparent in 27% (6/22) of tumours without lymph node or distant metastases (T1-4N0M0), in 54% (7/13) of tumours with lymph node and without distant metastases (T1-4N > or = 1M0) and in 47% (9/35) of tumours with distant metastases. Poorly differentiated tumours (G3-4) were positive in 42% (15/36) and well-differentiated tumors (G1-2) in 39% (7/18) of cases. In only 1 patient was the beta-hCG level in serum elevated, however. CONCLUSIONS: beta-hCG-Positive gastric carcinomas are found more frequently in advanced tumour stages and poorly differentiated carcinomas. These carcinomas, however, seem not to excrete beta-hCG in sufficient amounts to produce measurable serum values. Therefore, beta-hCG cannot be used a prognostic factor or for course control. The relevance of beta-hCG expression of tumour cells to the patients' prognosis remains obscure.

[Stem cell supported high dose chemotherapy (HDCT) in primary treatment of advanced ovarian carcinoma]. / Stammzellgestützte Hochdosischemotherapie [HDCT] in der Primärbehandlung des fortgeschrittenen Ovarialkarzinoms.

The standard treatment for ovarian cancer consists of staging laparotomy with aggressive debulking, a pelvic and paraaortal lymphadenectomy if indicated and a postoperative chemotherapy. A reappraisal of primary high dose chemotherapy in advanced ovarian cancer seems warranted because of high remission rates of such schedules in palliative situations. For a nation-wide interdisciplinary phase I/II multi-center-study 49 patients were recruited. Induction for stem cell mobilization consists of two cycles of cyclophosphamide and taxol. Three high dose cycles follow with a steady dose-escalation of carboplatin by a factor of 4, this is contrast to a conventionally dosed chemotherapy. During the first two cycles taxol is added, during the third etoposide and melphalane. The plan of primary sequential high dose therapy proved feasible in this study. In a prospective randomized follow-up study primary high dose therapy is compared to conventional chemotherapy (AGO-Ovar-5-study). It results will answer the question whether primary high dose chemotherapy with stem cell support improves the course of ovarian cancer compared to conventional treatment.

Dendritic cell immunotherapy induces antitumour response in parathyroid carcinoma and neuroendocrine pancreas carcinoma.

Parathyroid carcinomas and neuroendocrine carcinomas of the pancreas are rare malignancies in humans. Because of their low radio- and chemosensibility, they fail to respond to conventional therapy. We therefore tested a dendritic cell immunotherapy in an attempt to control the tumour growth in two patients. Studies on mice and humans have demonstrated the potent capacity of dendritic cells to induce specific antitumour immunity. Mature dendritic cells were generated from peripheral blood monocytes in the presence of granulocyte/macrophage colony-stimulating factor, interleukin 4 and tumour necrosis factor alpha. Dendritic cells were either loaded with parathyroid hormone (PTH) or with (pancreas) tumour-derived lysate (TL), respectively, and were delivered by subcutaneous injections. All immunizations were well tolerated with no side effects, and were administered on an outpatient basis. After repeated vaccinations, specific in vivo immune response was demonstrated by positive delayed-type hypersensitivity (DTH) toward PTH or TL, demonstrating the efficient generation of antigen-specific memory T-cells. DTH reactivity was accompanied by a significant decrease of tumour markers in both patients. This approach might be generally applicable to other advanced, radio- and chemotherapy-resistant endocrine malignancies.

Pitfalls in imaging Hodgkin's disease with computed tomography and positron emission tomography using fluorine-18-fluorodeoxyglucose.

We report on a patient with Hodgkin's disease who presented with hypodense splenic lesions and corresponding increased glucose metabolism in FDG-PET imaging, four months after completion of initial treatment, suggestive of early relapse. Serological testing for toxoplasma gondii, however, showed evidence of a recently reactivated or newly acquired infection. Three weeks after immediate antibiotic treatment with Daraprime and Sulfadiazin, the splenic lesions had completely resolved. Additionally, serological titers for toxoplasma gondii were normalized and whole body FDG-PET imaging showed no metabolic activity. Although the positive predictive value of PET imaging to indicate lymphoma is reported to be higher than CT, hypermetabolic lesions are not specific for malignant tissue. Whereas benign tumors typically show low glucose metabolism, activated granulocytes and macrophages may display significantly increased glucose consumption. In conclusion, our case report shows that although therapeutic decisions are often based on the results of imaging modalities, the taking of a detailed history and the acquisition of histological confirmation of the suspected lymphoma relapse are also advisable where possible. Cellular immunodeficiency can result in severe infections even in patients with intermediate stage Hodgkin's lymphoma in remission after combined modality treatment. Therefore, despite the high sensitivity of FDG-PET imaging for the detection of recurrent lymphoma, the differential diagnosis of infectious lesions should be kept in mind, in particular in immunocompromised patients.

Combination of interleukin-2 and interferon-alpha in renal cell carcinoma and malignant melanoma: a phase II clinical trial.

A total of 22 patients with metastatic renal cell carcinoma or malignant melanoma were treated in a phase II study to assess the safety and efficacy of combination therapy of interleukin-2 (IL-2) and interferon-alpha (IFN-alpha). 3 x 10(6) U/m2/day recombinant human (rh)IL-2 was given in repetitive cycles by continuous 24-h infusion from day 1 to day 4; 6 x 10(6) U/m2/day rhIFN-alpha was given subcutaneously on days 1 and 4. There was one complete remission and two partial remissions in the renal cell carcinoma group and two partial remissions in the malignant melanoma group, giving an overall response rate of 24% in 21 evaluable patients with a median response duration of 5+ months. Toxicity was moderate, with hypotension, fever, chills, nausea, neurotoxicity, and dermatitis as prominent side effects. Measurement of circulating cytokine levels showed increased serum tumor necrosis factor-alpha (TNF), interferon-tau, and soluble interleukin-2 receptor levels during each cycle with a tendency to higher concentrations of TNF in responders as compared to nonresponders. With regard to therapeutic efficacy and tolerance, our approach might represent an alternative to the high-dose protocols and the labor- and cost-intensive strategies of adoptive immunotherapy.

Therapy of invasive aspergillosis with itraconazole: improvement of therapeutic efficacy by early diagnosis.

We report on the treatment of invasive aspergillosis with the new triazole antimycotic agent itraconazole. All 11 patients suffered from pulmonary invasive aspergillosis. Two patients also had cerebral aspergillosis; in one of these patients the paranasal sinuses were also invaded. Underlying diseases were acute lymphoblastic leukaemia (n = 3), acute myeloid leukaemia (n = 4); one patient underwent allogeneic bone marrow transplantation before he developed aspergillosis; another was transplanted after successful aspergillosis treatment, liver cirrhosis (n = 1), lung infarction after pulmonary embolism (n = 1), chronic bronchitis after pulmonary tuberculosis (n = 1) and AIDS (n = 1). In five cases initial diagnosis was established by means of mycological methods and clinical signs. In six patients invasive pulmonary aspergillosis was initially diagnosed due to the clinical criteria presented in this paper. Secondary mycological confirmation after onset of therapy was achieved in five out of these six patients. All of the patients initially responded to therapy. One female patient experienced a relapse of aspergillosis and died of cerebral involvement and relapsing leukaemia. Two further patients died due to underlying diseases (pulmonary embolism, relapsing leukaemia). Nine patients (82%) were cured of the mycosis, including the patient with cerebral involvement; two underwent surgical resection of residual pulmonary lesions. Itraconazole is a very effective drug for treatment of invasive aspergillosis. Therapeutic efficacy can be optimized by early diagnosis using clinical criteria and prompt start of treatment.

The severe combined immunodeficient-human peripheral blood stem cell (SCID-huPBSC) mouse: a xenotransplant model for huPBSC-initiated hematopoiesis.

Mononuclear cells (MNCs) containing peripheral blood stem cells (PBSCs) were obtained from solid-tumor patients undergoing mobilizing chemotherapy followed by granulocyte colony-stimulating factor for PBSC transplantation-supported dose-intensified anticancer chemotherapy and were transplanted into unconditioned "nonleaky" young severe combined immunodeficient mice. Multilineage engraftment was shown by flow cytometry and immunocytochemistry using monoclonal antibodies to various human cell surface antigens as well as identification of human immunoglobulin in murine sera. Within a dose range of MNCs suitable for transplantation (10 to 36 x 10(6) cells/graft) the number of CD34+ cells injected (optimal at > 0.7 x 10(6)/graft) determined the yield of human cells produced in recipient animals. Engraftment of hu PBSC preparations resulted in prolonged generation of physiologic levels of human cytokines including interleukin-3 (IL-3), IL-6, and granulocyte-macrophage colony-stimulating factor, which were detectable in the murine blood over a period of at least 4 months. In vivo survival of immature human progenitor cells was preserved even 9 months after transplantation. Because human IL-3 is known to stimulate early hematopoiesis, a rat fibroblast cell line was stably transfected with a retroviral vector carrying the human IL-3 gene and cotransplanted subcutaneously as additional source of growth factor. Cotransplants of this cell line producing sustained in vivo levels of circulating human IL-3 for at least 12 weeks significantly accelerated the process of engraftment of huPBSC and spurred the spread of mature human cells to the murine spleen, liver, thymus, and peripheral blood. Cotransplants of allogeneic human bone marrow stromal cells derived from long-term cultures resulted in a comparable--though less prominent--support of engraftment.

Haematopoietic reconstitution after autologous transplantation of CD34(+)-selected versus non-selected peripheral blood progenitor cells.

Selection of CD34+ cells for autologous transplantation is increasingly being used to reduce potential tumor cell contamination of the autograft. Haematopoietic reconstitution in 40 patients after transplantation of CD34(+)-selected versus non-selected G-CSF-mobilized PBPC was compared and was almost identical in the two groups of patients. Delayed platelet engraftment was only observed in patients transplanted with a CD34+ cell dose of < 2.5 x 10(6)/kg body weight. It has to be shown whether the positive selection of CD34+ cells will improve the disease free survival after autologous PBPC transplantation.