Abnormal Neutrophil Chemotaxis after Successful Bone Marrow Transplantation

Twenty patients with self-sustaining hematopoiesis were evaluated for neutrophil functions and bone marrow histology 7 to 34 months after bone marrow transplantation (BMT) (7 allogeneic, 13 autologous) performed for acute leukemia in complete remission (11 patients), Hodgkin's lymphoma (2 patients), chronic myeloid leukemia (6 patients) or severe aplastic anemia (1 patient). The chemotactic response toward zymosan-treated serum was severely depressed (<35% of normal) in peripheral neutrophils of 11 patients (2 allogeneic and 9 autologous BMT) and moderately defective (35-70% of normal) in 5 others (2 allogeneic and 3 autologous BMT). On the other hand, phagocytic activity, activation of the metabolic burst and surface expression of CD11/CD18 molecules were within normal limits or moderately increased. The chemotactic defect was independent of age, sex, conditioning regimen and the time period after marrow infusion. The incidence of defective chemotaxis was much greater in patients receiving an autologous BMT (92% of the patients) than in those who had an allogeneic BMT (57% of the patients). Simultaneous bone marrow biopsy studies showed significant stromal alterations in most of our patients; since the bone marrow microenvironment plays an essential role in the process of blood cell formation and release, these observations suggest that defective neutrophil chemotaxis may well serve as a marker of abnormal post-transplant hematopoiesis.

Noninvasive near-infrared live imaging of human adult mesenchymal stem cells transplanted in a rodent model of Parkinson's disease

BACKGROUND

We have previously shown that human mesenchymal stem cells (hMSCs) can reduce toxin-induced neurodegeneration in a well characterized rodent model of Parkinson's disease. However, the precise mechanisms, optimal cell concentration required for neuroprotection, and detailed cell tracking need to be defined. We exploited a near-infrared imaging platform to perform noninvasive tracing following transplantation of tagged hMSCs in live parkinsonian rats.

METHODS

hMSCs were labeled both with a membrane intercalating dye, emitting in the near- infrared 815 nm spectrum, and the nuclear counterstain, Hoechst 33258. Effects of near-infrared dye on cell metabolism and proliferation were extensively evaluated in vitro. Tagged hMSCs were then administered to parkinsonian rats bearing a 6-hydroxydopamine-induced lesion of the nigrostriatal pathway, via two alternative routes, ie, intrastriatal or intranasal, and the cells were tracked in vivo and ex vivo using near-infrared technology.

RESULTS

In vitro, NIR815 staining was stable in long-term hMSC cultures and did not interfere with cell metabolism or proliferation. A significant near-infrared signal was detectable in vivo, confined around the injection site for up to 14 days after intrastriatal transplantation. Conversely, following intranasal delivery, a strong near-infrared signal was immediately visible, but rapidly faded and was completely lost within 1 hour. After sacrifice, imaging data were confirmed by presence/absence of the Hoechst signal ex vivo in coronal brain sections. Semiquantitative analysis and precise localization of transplanted hMSCs were further performed ex vivo using near-infrared imaging.

CONCLUSION

Near-infrared technology allowed longitudinal detection of fluorescent-tagged cells in living animals giving immediate information on how different delivery routes affect cell distribution in the brain. Near-infrared imaging represents a valuable tool to evaluate multiple outcomes of transplanted cells, including their survival, localization, and migration over time within the host brain. This procedure considerably reduces the number of animal experiments needed, as well as interindividual variability, and may favor the development of efficient therapeutic strategies promptly applicable to patients.

Cancer stem cells in hematological disorders: current and possible new therapeutic approaches

An increasing body of evidence has shown that hematologic malignancies, alike normal hematopoiesis, has a hierarchical structure including a stem cell compartment with self renewal capability, endowed in a neoplastic niche bearing resemblance to its normal hematopoietic counterpart. According to experimental data on NOD-SCID mice, leukemic stem cells are characterized by a CD34+/CD38- surface profile and account for 1 in 10(3) to 1 in 10(6) of the total amount of leukemic cells. The available knowledge about leukemic stem cells (LSC) has arisen the question as to whether some targeting of LSC is achieved by current treatments; the answer is dubitative at best, with the possible exception of arsenic trioxide in promyelocytic leukemia. On the other side, the unsatisfactory results in the treatment of many hematological neoplasms has prompted many research groups to find out whether direct targeting of LSC, possibly in its niche, would result in an improvement in cure rates. This approach implies the identification of LSC specific markers, clearly distinct from their normal counterpart in order to spare normal hematopoietic stem cells. Adhesion/surface antigens, metabolic pathways involved in LSC survival and renewal, telomerase, commonly mutated genes and epigenetic phenomena have been investigated as candidate targets for newer therapeutic strategies. So far, most of the possibly effective agents have been studied in experimental models only. FLT-3 inhibitors account for a notable exception since they have resulted effective in vivo in AML with mutated, but not over expressed, FLT-3. A main task for the future is to find out whether some common LSC specific markers would be identifiable in a substantial proportion of AML cases, or whether each AML case shows a unique fingerprint of markers. In the latter event, targeting of LSC could result in an arduous task.

Recombinant human erythropoietin stimulates vasculogenesis and wound healing in a patient with systemic sclerosis complicated by severe skin ulcers

Systemic sclerosis (SSc) is often complicated by severe skin ulcers that are unresponsive to traditional treatments. Vascular alterations are responsible for the ischaemic features of the disease in both the skin and visceral organs. Defective neoangiogenesis correlates with an abnormally reduced quantity of circulating endothelial progenitor cells (EPCs) caused by impaired maturation potential and proliferative capacity of bonemarrow endothelial stem cells. We report a patient with nonhealing cutaneous ulcers successfully treated with recombinant human erythropoietin (rHuEPO). The possible biological effects of this drug were also investigated. Before rHuEPO treatment, the bone-marrow sample contained reduced numbers of EPCs, which were functionally impaired. After a 6-month rHuEPO cycle, a marked increase in endothelial progenitor markers was seen, along with a significant reduction in their apoptotic rates. The clinical and laboratory data variations before and after rHuEPO treatment give new insights into the pathogenetic role of impaired endothelial stem-cell maturation and defective neoangiogenesis in patients with SSc.

A comparison between metabolic syndrome post-hematopoietic stem cell transplantation and spontaneously occurring metabolic syndrome

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) is used in the treatment of several hematological and non-hematological disorders. An increasing number of long-term survivors recover from their primary disease, but they are at risk of adverse late effects, including metabolic syndrome (MS), which seems to be common in long-term survivors of HSCT.

AIM

To compare common metabolic parameters and adipohormone profiles in post-transplant and spontaneously occurring or "classic" MS patients.

SUBJECTS AND METHODS

Post-transplant MS patients (15 women and 14 men; 49.8±9.3 yr) were compared to "classic" MS patients (15 women and 14 men; 52.9±8.0 yr). For each subject a record of conventional clinical parameters was made; moreover, serum leptin, insulin, quantitative C-reactive protein (CRP), tumor necrosis factor-α [TNF-α], and adiponectin concentrations were measured.

RESULTS

The patients with post-HSCT MS had significantly higher levels of leptin, CRP, and TNF-α than the patients with "classic" MS. A generalized linear model comprising serum insulin (p=0.022), body mass index (p<0.001), gender (p<0.001), and group (i.e. healthy, post-HSCT with MS, or suffering from "classic" MS; p<0.001) explained serum leptin variability (adjusted R(2)=0.741). Serum leptin concentrations and BMI were related in the patients with "classic" MS but not in those with post-HSCT MS.

CONCLUSIONS

A possible pathogenetic mechanism in the development of MS after HSCT could be hyperleptinemia. A potential interaction among circulating leptin, components of MS, and immune function might explain the role of this adipokine in mediating cardiovascular risk after HSCT.

Risk of hepatitis B surface antigen seroreversion after allogeneic hematopoietic SCT

Allogeneic hematopoietic SCT (HSCT) increases the risk of hepatitis B virus (HBV) reactivation in hepatitis B surface antigen (HBsAg) carriers but the incidence, risk factors and course of HBV reactivation after HSCT in HBsAg-negative/anti-hepatitis B core antigen (anti-HBc)-positive recipients are not well known. A total of 50 HBsAg-negative/anti-HBc-positive HSCT recipients with onco-hematological diseases, underwent sequential clinical and laboratory examinations, including serum HBsAg, during follow-up. Serum HBV DNA collected at HSCT was retrospectively amplified by a sensitive PCR assay. During 17 months of follow-up, six (12%) patients had seroreverted to HBsAg, 7-32 months after HSCT, with 1- and 5-year cumulative rates of 13 and 22%. HBsAg seroreversion was associated with serum HBeAg higher than 8 log₁₀ copies per ml HBV DNA and a 1.5 to 36 fold increase of serum alanine aminotransferase leading to HBeAg-positive chronic hepatitis B in all patients. Patients with chronic onco-hematological disease and long-lasting immunosuppression following HSCT had a higher risk of HBsAg seroreversion independently of serum HBV DNA levels at HSCT. HBsAg-negative/anti-HBc-positive HSCT recipients with chronic onco-hematological disease carry a significant risk of HBsAg seroreversion and HBeAg-positive chronic hepatitis B, independently of serum levels of HBV DNA at transplantation.

Endothelial precursors and mature endothelial cells are increased in the peripheral blood of myelodysplastic syndromes

Increased angiogenesis has been demonstrated to be a significant prognostic factor in many solid tumors. In the oncohematological setting, it has been associated with myelodysplastic syndromes (MDS), chronic myeloid leukemia, acute lymphoid, and myeloid leukemias. Recently, increased circulating endothelial cells (CECs) have been associated with breast cancer and non-Hodgkin lymphoma (NHL). Based on these premises we analysed total and activated CECs, and endothelial precursors (CEPs) in 50 MDS patients and 20 healthy donors. CECs and CEPs were quantified by flow cytometry. CEC levels were compared with bone marrow (BM) microvessel density (MVD). In addition, some angiogenic factors, namely vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and soluble VEGF-Receptor2 (VEGFR2), were tested in the sera from 25 MDS patients. Total, activated CECs and CEPs were significantly increased in MDS when compared to control group (p<0.0001); whereas in the MDS cases no association was found with French--American--British (FAB), International Prognostic Scoring System (IPSS) subtypes or survival. Patients with higher CECs also showed higher MVD. Among the cytokines analysed, sVEGFR2 was significantly higher in the lower IPSS risk classes, while the levels of bFGF directly correlated with total and activated CECs. Taken together these data strengthen the hypothesis of a possible role of angiogenesis in MDS pathogenesis.

Autologous haematopoietic stem cell transplantation without CD34+ cell selection in refractory Crohn's disease

OBJECTIVES

Autologous haematopoietic stem cell transplantation (HSCT) with CD34(+) cell selection has recently been used in the treatment of refractory Crohn's disease, showing good safety and promising efficacy. We investigated the safety and efficacy of HSCT with unselected peripheral blood stem cells (PBSCs) in moderate-severe refractory Crohn's disease.

PATIENTS

Four patients (three male, one female; age range 26-45 years) with active moderate-severe Crohn's disease (median Crohn's Disease Activity Index (CDAI) 319, range 272-345), refractory or intolerant to multiple drugs including infliximab, were enrolled.

INTERVENTIONS

Unselected PBSCs were collected after mobilisation with cyclophosphamide (CTX) 1.5 g/m2 and granulocyte-colony stimulating factor (G-CSF) 10 microg/kg. The conditioning regimen included CTX 50 mg/kg on days -5 to -2 and rabbit anti-thymocyte globulin (ATG) 2.5 mg/kg on days -4 to -2.

MAIN OUTCOME MEASURES

Primary endpoints were toxicity and clinical remission (CDAI<150) at 3 months. Secondary endpoints were clinical and endoscopic response at 3 months and toxicity, clinical and endoscopic remission at 12 months.

RESULTS

No improvement or slight deterioration was observed following mobilisation (median CDAI 339, range 258-404). At the third month, the primary endpoint of clinical remission was achieved in all patients, with a median CDAI of 91 (range 56-102), and complete endoscopic remission was achieved in 2/3 patients. After a median follow-up of 16.5 months, 3/4 patients maintained both clinical and endoscopic remission, despite withdrawal of all drugs, and complete fistula closure was observed in all affected patients. No deaths or life-threatening infection occurred. Unexpected adverse events included a perianal abscess after mobilisation in one patient, pleural and pericardial effusions in another and BK virus-related macrohaematuria in another, all rapidly resolved with conservative treatment.

CONCLUSION

Autologous HSCT with unselected PBSC appears to be safe and can induce and maintain remission in previously refractory Crohn's disease patients.

Indeterminate cell histiocytosis in association with later occurrence of acute myeloblastic leukaemia

Indeterminate cell histiocytosis (ICH) is a proliferation of indeterminate CD1a+, CD68+, S100+ and CD207- dermal dendritic cells. We describe a 39-year-old man who developed diffuse ICH and, 6 years later, acute myeloblastic leukaemia (AML). He was treated with cyclophosphamide, etoposide and vinblastine until 2003. In August 2004, he presented dyspnoea, hyperpyrexia and infiltration of the lung parenchyma, compatible with an AML invasion, and died after a course of induction chemotherapy. Cytomorphology and immunophenotype analyses suggested an ICH clonal evolution. The leukaemogenic role of etoposide is discussed. ICH has previously been reported in association with B-cell malignancy, but only one case has shown systemic progression.

Prospective study on the behaviour of the metalloprotease ADAMTS13 and of von Willebrand factor after bone marrow transplantation

Thrombotic microangiopathies (TMAs) are rare but serious complications of bone marrow transplantation (BMT). Clinical manifestations are similar to those of thrombotic thrombocytopenic purpura (TTP), but prognosis is generally poorer despite plasma exchange. The enzymatic activity of the plasma metalloprotease ADAMTS13, which cleaves ultralarge thrombogenic multimers of von Willebrand factor (VWF) derived from activated endothelial cells, is very low or undetectable in patients with classic TTP, and protease deficiency is thought to play a mechanistic role in the formation of platelet thrombi in the microcirculation. This is the first prospective study to evaluate the incidence of TMA in 46 consecutively recruited patients undergoing autologous or allogeneic BMT and explore in parallel the behaviour of ADAMTS13, VWF antigen and VWF multimer size. The incidence of post-BMT TMA was 6% (three of 46); all cases occurred after allogeneic BMT. Compared with baseline values plasma ADAMTS13 activity was significantly reduced in patients undergoing BMT, particularly after the conditioning regimen (mean values: 50 +/- 22 vs. 77 +/- 32%; P < 0.0001). In the three patients who developed TMA, ADAMTS13 decreased after conditioning, but was very low in one case only (8%). VWF antigen levels progressively increased after the conditioning regimen (228 +/- 75 vs. 178 +/- 76% at baseline, P = 0.002). The mean proportion of high-molecular weight VWF multimers did not change in the various stages of BMT, even though ultralarge multimers were transiently found in same cases with and without TMA. Hence, the measurements evaluated in this study are not clinically useful to predict the occurrence of post-BMT TMA.

Sensitivity of human multiple myelomas and myeloid leukemias to the proteasome inhibitor I

The proteasome inhibitor PSI is potently cytotoxic in vitro against human chronic myeloid leukemia (CML) and acute myeloid leukemias (AML). Here, we have tested proteasome inhibitor I (PSI) in a panel of 11 human multiple myeloma (MM) cell lines and found that it has antiproliferative activity, with an IC50 between 4.5 and 557 nM at 48 h. PSI potentiated the toxicity of a number of chemotherapeutic agents in myeloid leukemia but not in MM cell lines, while in combination with therapeutic proteasome inhibitor PS-341 (Bortezomib) it had a synergistic effect. PSI suppressed the growth of AML cell lines more effectively than PS-341. CFU-GM colony assays revealed that CD34+ bone marrow progenitors from CML and AML patients were more sensitive to PSI than those from normal subjects (IC50: 5, 15 and 50 nM for AML, CML and normal, respectively). Moreover, the growth of normal primitive progenitors (LTC-IC) was unaffected by 15 nM PSI (P=0.576). PSI-induced cell death required RNA transcription and protein synthesis, but not DNA replication, was accompanied by the upregulation of Bcl-2 and modest reduction of Bax and Bcl-XL proteins, and involved the activation of caspases 2, 3, 7 and 8. These findings lend additional support to preclinical investigations with PSI.

Neuro-glial differentiation of human bone marrow stem cells in vitro

Bone marrow (BM) is a rich source of stem cells and may represent a valid alternative to neural or embryonic cells in replacing autologous damaged tissues for neurodegenerative diseases. The purpose of the present study is to identify human adult BM progenitor cells capable of neuro-glial differentiation and to develop effective protocols of trans-differentiation to surmount the hematopoietic commitment in vitro. Heterogeneous cell populations such as whole BM, low-density mononuclear and mesenchymal stem (MSCs), and several immunomagnetically separated cell populations were investigated. Among them, MSCs and CD90+ cells were demonstrated to express neuro-glial transcripts before any treatment. Several culture conditions with the addition of stem cell or astroblast conditioned media, different concentrations of serum, growth factors, and supplements, used alone or in combinations, were demonstrated to alter the cellular morphology in some cell subpopulations. In particular, MSCs and CD90+ cells acquired astrocytic and neuron-like morphologies in specific culture conditions. They expressed several neuro-glial specific markers by RT-PCR and glial fibrillary acid protein by immunocytochemistry after co-culture with astroblasts, both in the absence or presence of cell contact. In addition, floating neurosphere-like clones have been observed when CD90+ cells were grown in neural specific media. In conclusion, among the large variety of human adult BM cell populations analyzed, we demonstrated the in vitro neuro-glial potential of both the MSC and CD90+ subset of cells. Moreover, unidentified soluble factors provided by the conditioned media and cellular contacts in co-culture systems were effective in inducing the neuro-glial phenotype, further supporting the adult BM neural differentiative capability.

Reduced-intensity conditioning lowers treatment-related mortality of allogeneic stem cell transplantation for chronic lymphocytic leukemia: a population-matched analysis

To elucidate whether reduced-intensity conditioning (RIC) decreases treatment-related mortality (TRM) after allogeneic stem cell transplantation (allo-SCT) for chronic lymphocytic leukemia (CLL), we retrospectively compared 73 RIC cases from a recent EBMT survey with 82 patients from the EBMT database who had undergone standard myeloablative conditioning (MC) for CLL during the same time period. The two populations were matched by adjusting the primary risk factor, the conditioning regimen, in a series of Cox models for age, sex, donor type, remission status at transplant and analyzed for its effect on TRM, relapse incidence, event-free (EFS) and overall survival (OS). After adjustment, a significant reduction of TRM became evident for the RIC population (hazard ratio (HR) 0.4 (95% confidence interval 0.18-0.9); P=0.03). On the other hand, RIC was associated with an increased relapse incidence (HR 2.65 (0.98-7.12); P=0.054). There was no significant difference between RIC and MC in terms of EFS (HR 0.69 (0.38-1.25); P=0.22) and OS (HR 0.65 (0.33-1.28); P=0.21). We conclude that RIC appears to favorably influence TRM after allo-SCT for CLL. This observation, as well as possible detrimental effects of RIC on relapse risk, should be confirmed by prospective studies.

Transdermal fentanyl in HSCT patients: an open trial using transdermal fentanyl for the treatment of oral mucositis pain

Fentanyl is a synthetic opioid that can be delivered through a transdermal therapeutic system (TTS). The aim of this study was to assess the efficacy of fentanyl TTS in treating oral mucositis pain in 75 adult hematopoietic stem cell transplant (HSCT) patients. The analysis was based on 62 patients who developed mucositis. Pain control was assessed by the patients using a visual analogue scale (VAS) from day 0 to day +33 after HSCT. Fentanyl TTS was administered at the patient's request. In all, 20 patients did not require fentanyl (group A). The first 22 patients asking for the patch received fentanyl 25 microg/h (group B) and the subsequent 20 patients received 50 microg/h (group C). There were no significant differences in pain relief between groups B and C. The expected effect of a decrease in mean pain score (mean of the VAS scores of all of the patients in the same group each day) following the application of fentanyl TTS was not noted. We can conclude that fentanyl TTS at the doses used in this study may not adequately relieve oral mucositis pain.

Treatment-related mortality and graft-versus-leukemia activity after allogeneic stem cell transplantation for chronic lymphocytic leukemia using intensity-reduced conditioning

Allogeneic stem cell transplantation (SCT) using reduced-intensity conditioning (RIC) has potential to be a promising treatment of aggressive chronic lymphocytic leukemia (CLL). Since available clinical data obtained with this novel approach are very limited, we have performed a survey on this issue. Data of 77 patients were collected from 29 European Group for Blood and Marrow Transplantation centers. Median age was 54 (30-66) years, and the median number of previous chemotherapy regimens was 3 (0-8). HLA-identical sibling donors were used in 81% of the cases. Moderate conditioning regimens (mainly low-dose total body irradiation (TBI) or fludarabine-cyclophosphamide combinations) were administered to 56% of the patients, whereas the remainder received more intense conditioning consisting of fludarabine-busulfan or high-dose melphalan combinations. In 40% of the patients, in vivo T-cell depletion (TCD) with anti-thymocyte globulin or CAMPATH-1H was part of the conditioning regimen. Cumulative treatment-related mortality (TRM) was 18% (95% CI 9; 27) after 12 months. Complete chimerism as well as best response was not achieved immediately post-transplant but took a median of 3 months to develop. The 2-year probability of relapse was 31% (95% CI 18; 44), with no event occurring later than 12 months post transplant in the absence of TCD. With one exception, relapses were not observed after onset of chronic graft-versus-host disease. Event-free and overall survival at 24 months were 56% (95% CI 43; 69) and 72% (95% CI 61; 83), respectively. The median follow-up was 18 (1-44) months. Donor lymphocyte infusions or secondary transplants were performed in 19 patients with insufficient disease control and/or incomplete donor chimerism post-transplant, leading to a response in seven patients (37%). Preliminary multivariate analysis identified less than PR at transplant (hazard ratio (HR) 3.5; P&<0.01) and alternative donor (HR 3.1; P=0.02) as significant risk factors for relapse, whereas number of previous regimens >2 (HR 5.4; P=0.03), TBI (HR 2.5; P=0.05), and alternative donor (HR 2.3; P=0.08) were risk factors for survival. We conclude that RIC might favorably influence the outcome after allogeneic SCT for CLL by reducing TRM while preserving graft-versus leukemia activity.

Treatment of advanced mycosis fungoides by allogeneic stem-cell transplantation with a nonmyeloablative regimen

SUMMARY

Given the poor prognosis of patients with advanced cutaneous T-cell lymphoma and the high transplant-related mortality associated with conventional allogeneic bone marrow transplantation, we performed nonmyeloablative transplantation of allogeneic stem cells (ASCT) from HLA-identical siblings in three patients with this disease. All patients achieved full donor engraftment, clearance of clonal T cells leading to durable complete remissions but experienced high incidence of infections, which proved fatal in one case. These results suggest that nonmyeloablative ASCT is a novel and potentially curative therapy for patients with advanced T-cell lymphomas who have a histocompatible sibling.

ABVD versus stanford V versus MEC in unfavourable Hodgkin's lymphoma: results of a randomised trial

BACKGROUND

Between January 1996 and April 2000, 355 patients with advanced Hodgkin's disease (HD) (stage II bulky disease, III and IV) were enrolled in a prospective, multicentre, randomised trial aimed at comparing the efficacy of two new promising regimens: Stanford V and MEC hybrid. ABVD was chosen as the control arm. Radiotherapy was planned at the end of induction therapy on residual masses or on sites of previous bulky lesions. One hundred and seventeen, 123 and 115 patients were treated with Stanford V, MEC and ABVD, respectively. The records of 275 enrolled patients (89 Stanford V, 88 MEC, 98 ABVD) have been reviewed and are the subject of this report.

RESULTS

After induction therapy a complete response (CR) was observed in 93, 89 and 74% of patients treated with MEC, ABVD and Stanford V, respectively, with a statistically significant difference (P = 0.013) between the arms. After a median follow-up of 24 months, 16 relapses have been recorded among 196 patients who achieved a CR. Relapse rates are 16, 6 and 4% for Stanford V, ABVD and MEC, respectively (P = 0.042). The 3-year survival was 93%, without any significant difference among the arms. However, a significant difference emerged in terms of failure free survival (FFS). Patients treated with Stanford V did the worst compared with those treated with ABVD or MEC (P = 0.001). Toxicity was comparable in the three treatment arms.

CONCLUSION

For this randomised study, both ABVD and MEC gave superior results to Stanford V in terms of response and FFS; MEC seems to be the best regimen in terms of relapse-free survival, even if a significant difference has not yet been achieved. Notwithstanding the short follow-up, these results seem to be very impressive in defining the best standard treatment for HD for this subset of patients.

Non-transferrin-bound iron in myelodysplastic syndromes: a marker of ineffective erythropoiesis?

INTRODUCTION

Iron overload is usually observed in patients (even untransfused) with myelodysplastic syndromes (MDS), and contributes towards the generation of low molecular weight iron complexes or non-transferrin-bound iron (NTBI), which in turn favors oxidative DNA damage and consequent apoptosis.

MATERIALS AND METHODS

Levels of NTBI and lipid peroxidation were evaluated by means of free serum malondyaldehyde (MDA) in untransfused MDS patients and we tried to correlate them with ineffective erythropoiesis, apoptosis and the pattern of in vitro growth.

RESULTS

NTBI levels were found to be significantly higher in low-risk than in high-risk MDS patients, as well as in patients with a lower myeloid/erythroid ratio. MDA was found to be uniformly higher in the MDS patients as a whole than in normal controls. The bone marrow progenitor cells in the MDS patients with high NTBI levels showed a higher degree of apoptosis, but this difference was not statistically significant. Patients with a leukemic growth pattern had lower NTBI levels than those with a non-leukemic pattern.

CONCLUSION

These data suggest that NTBI is related to the degree of ineffective erythropoiesis and that it contributes towards inducing apoptosis in MDS bone marrow precursors. The presence of leukemic growth is associated with low NTBI levels, probably due to increased iron consumption by blast cells.

Differentiation and expansion of endothelial cells from human bone marrow CD133(+) cells

We report a method of purifying, characterizing and expanding endothelial cells (ECs) derived from CD133(+) bone marrow cells, a subset of CD34(+) haematopoietic progenitors. Isolated using immunomagnetic sorting (mean purity 90 +/- 5%), the CD133(+) bone marrow cells were grown on fibronectin-coated flasks in M199 medium supplemented with fetal bovine serum (FBS), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and insulin growth factor (IGF-1). The CD133(+) fraction contained 95 +/- 4% CD34(+) cells, 3 +/- 2% cells expressing VEGF receptor (VEGFR-2/KDR), but did not express von Willebrand factor (VWF), VE-cadherin, P1H12 or TE-7. After 3 weeks of culture, the cells formed a monolayer with a typical EC morphology and expanded 11 +/- 5 times. The cells were further purified using Ulex europaeus agglutinin-1 (UEA-1)-fluorescein isothiocyanate (FITC) and anti-FITC microbeads, and expanded with VEGF for a further 3 weeks. All of the cells were CD45(-) and CD14(-), and expressed several endothelial markers (UEA-1, VWF, P1H12, CD105, E-selectin, VCAM-1 and VE-cadherin) and typical Weibel-Palade bodies. They had a high proliferative potential (up to a 2400-fold increase in cell number after 3 weeks of culture) and the capacity to modulate cell surface antigens upon stimulation with inflammatory cytokines. Purified ECs were also co-cultivated with CD34(+) cells, in parallel with a purified fibroblastic cell monolayer. CD34(+) cells (10 x 10(5)) gave rise to 17,951 +/- 2422 CFU-GM colonies when grown on endothelial cells, and to 12,928 +/- 4415 CFU-GM colonies on fibroblast monolayers. The ECs also supported erythroid blast-forming unit (BFU-E) colonies better. These results suggest that bone marrow CD133(+) progenitor cells can give rise to highly purified ECs, which have a high proliferative capacity, can be activated by inflammatory cytokines and are superior to fibroblasts in supporting haematopoiesis. Our data support the hypothesis that endothelial cell progenitors are present in adult bone marrow and may contribute to neo-angiogenesis.

FISH characterization of t(8;12)(q12;p13) observed as the sole karyotypic anomaly in a myelodysplastic syndrome patient

We report a t(8;12)(q12; p13) as the sole cytogenetic anomaly in a patient with a myelodysplastic syndrome (MDS). By means of FISH, we mapped the genomic region involved in the breakpoint (bkp) on both chromosomes. The 12p13 bkp mapped between markers WI-664 and WI-9218, immediately distal to the breakpoint cluster region frequently involved in hematological neoplasms targeted by y964C10. The 8q12 bkp (not yet investigated by FISH) was characterized and found to occur between markers WI-3263 and D8S524 within the region recognized by y874E10.

Ultrastructural features of CD34+ hematopoietic progenitor cells from bone marrow, peripheral blood and umbilical cord blood

Hematopoietic progenitor cells from different sources have been widely characterized, but their ultrastructural morphology has never been described in detail. In this study, imunomagnetically separated CD34+ cells from normal bone marrow (BM), mobilized peripheral blood (PBSC) and human umbilical cord blood (CB) were studied by transmission electron microscopy (TEM) using a cytochemical method which reveals endogenous myelo-peroxidase (MPO) activity. This technique is particularly suited for detecting early signs of the myeloid commitment. The CD34+ cells from PBSC were morphologically very homogeneous and 94.7+/-4.5% of these cells were MPO-: these ultrastructural features are generally considered typical of immature cells. The CD34+ BM cells were instead more heterogeneous, with 24.6+/-7.4% showing intense MPO activity. The ultrastructural characteristics of CB cells fell between those observed in PBSC and BM, but there was a high percentage of morphologically immature cells with no evidence of MPO activity (about 83%). The number of apoptotic cells within samples from different sources was also examined both by TEM and flow cytometry. The percentage of apoptotic cells was 0.7% in PBSC, 2.3% in BM, 2.9% in CB from vaginal delivery and 11.6% in CB from cesarean section. These observations confirm the relative phenotypic immaturity of CB in comparison with BM cells; they also suggest that CB collected after cesarean section may be associated with reduced stem cells viability.

Efficient retrovirus-mediated transduction of primitive human peripheral blood progenitor cells in stroma-free suspension culture

Retroviral transduction of hematopoietic cells has resulted in unsatisfactory gene marking in clinical studies. Since cytokine-stimulated stem cells have engrafted poorly in animal models, we investigated phenotypic changes during culture of peripheral blood progenitor cells (PBPC). Human CD34(+) HLA-DR(low) cells, immunomagnetically separated from PBPC collections, were found to extrude rhodamine-123, which is characteristic for primitive hematopoietic cells. Cells were grown in suspension cultures supplemented with cytokines. While interleukin-3-containing factor combinations promoted cell proliferation they caused loss of rhodamine-123 extrusion and reduced the frequencies of cobblestone area-forming cells (CAFC). Several other cytokines failed to stimulate cell divisions, which are required for retroviral transduction. A combination including Flt-3 ligand (FL), interleukin-6 and stem cell factor (SCF) preserved an immature phenotype for 5 to 6 days and stimulated cell divisions, which was improved upon addition of leukemia inhibitory factor and interleukin-11. Furthermore, the CAFC frequency among cells treated with these cytokines was increased as compared with widely used cocktails containing interleukin-3, interleukin-6 and SCF. Rhodamine-123 appeared to be a particularly sensitive indicator for differentiation of PBPC. For analysis of gene transfer, amphotropic retroviruses conferring an MDR1 cDNA were added repeatedly for 6 days to cytokine-treated PBPC stroma-free cultures. Proviral cDNA was detected by polymerase chain reaction in 68% of cobblestone areas derived from CD34(+)HLA-DR(low) cells that had been exposed to Flt-3 ligand, interleukin-6 and SCF. In summary, conditions were identified that facilitate efficient transduction of early PBPC with amphotropic retroviruses while preserving a primitive phenotype for extended periods.

Complications of autologous hematopoietic stem cell transplantation

Myeloablative therapy followed by autologous hematopoietic stem cell (HSC) transplantation is a therapeutic option proposed for a variety of hematological and non-hematological diseases. However, although mortality due to this procedure is steadily decreasing, patients are still exposed to the risk of a number of complications negatively affecting their expectancy or quality of life. Adverse events due to HSC harvesting are rare and generally reversible. The early post-transplant complications include infections, mucositis, hepatic veno-occlusive disease and various acute organ toxicities. Immune derangement is a leading cause of most late events, such as viral or fungal infections, auto-immune manifestations and secondary neoplasms, of which secondary AML/MDS are the most commonly reported. In line with the favoured pathogenetic explanation, neoplastic clones previously established during conventional treatment are harvested and reinfused at the time of autografting. Other late effects are single organ dysfunction due to the underlying disease and treatment toxicities combined with infectious and post-infectious phenomena. The lungs, heart, CNS and reproductive system are the most investigated targets, but no clinical patterns have been identified as specific for autografting.

The apoptogenic response of human myeloid leukaemia cell lines and of normal and malignant haematopoietic progenitor cells to the proteasome inhibitor PSI

Degradation of several intracellular proteins involved in cell cycle control and tumour growth is regulated by the ubiquitin-dependent multicatalytic protease complex (proteasome). We report that proteasome inhibitor Z-Ile-Glu(OtBu)-Ala-Leucinal (PSI) was cytotoxic on most human myeloid leukaemia cell lines at IC50 doses ranging from 5 to 25 nmol/l. Additionally, PSI pre-treatment enhanced cytotoxicity by taxol and cisplatinum. PSI was more active on leukaemic than on normal CD34(+) bone marrow progenitors because the 50% growth inhibition of colony-forming unit granulocyte macrophage (CFU-GM) from cases of chronic myelogenous leukaemia (CML) and normal subjects was achieved by 15 nmol/l and 50 nmol/l PSI respectively. PSI killed cells by apoptosis as revealed by ultrastructural changes, nuclear DNA fragmentation, cleavage of poly (ADP-ribose) polymerase (PARP) and of beta-catenin, and was antagonized by ectopic expression of Bcl-2 but not by inactivating mutations of p53. This event was associated with a slight accumulation of Bcl-2, a decrease of Bax but no changes in Bcl-X(L) protein expression at any time point. In Ph(+) cell lines BCR-ABL protein was only down-regulated after 48 h of treatment with 10 nmol/l PSI. Altogether, these results indicate that PSI, alone or in association with other cytotoxic agents, has anti-tumour activity against myeloid malignancies and is more effective on leukaemic than on normal haematopoietic progenitor cells.

Hyperhomocysteinemia in myelodysplastic syndromes: specific association with autoimmunity and cardiovascular disease

Hyperhomocysteinemia (HH) has been associated with cardiovascular and autoimmune diseases and oxidative cell damage. Myelodysplastic syndromes (MDS) are associated with autoimmunity (AI) and increased oxidative stress. We tested the association of HH and oxidative stress in 33 MDS patients, by measuring plasma homocysteine and malondialdehyde (MDA). HH was found in 42% of cases, (4/5) cases with associated cardiovascular events (CVE)(80%), and 9/15 cases with associated AI (60%). Thus in MDS, HH was significantly associated with AI/CVE (chi(2) : p=0.0011), and this association seems to be specific, as demonstrated by the comparison of MDS presenting AI/CVE with the ischemic cardiopathy/rheumatoid arthritis control group (13/20, 65% vs 19/69, 27%; chi(2) : p=0.0021). The levels of MDA indicated increased oxidative stress. Our data may suggest that in a subset of MDS, HH may simultaneously contribute to bone marrow myelodysplasia, CVE and AI pathogenesis, possibly through oxidative cell damage.

Cidofovir for cytomegalovirus infection and disease in allogeneic stem cell transplant recipients. The Infectious Diseases Working Party of the European Group for Blood and Marrow Transplantation

A retrospective study was performed to collect information regarding efficacy and toxicity of cidofovir (CDV) in allogeneic stem cell transplant patients. Data were available on 82 patients. The indications for therapy were cytomegalovirus (CMV) disease in 20 patients, primary preemptive therapy in 24 patients, and secondary preemptive therapy in 38 patients. Of the patients, 47 had received previous antiviral therapy with ganciclovir, foscarnet, or both drugs. The dosage of CDV was 1 to 5 mg/kg per week followed by maintenance every other week in some patients. The duration of therapy ranged from 1 to 134 days (median, 22 days). All patients received probenecid and prehydration. Ten of 20 (50%) patients who were treated for CMV disease (9 of 16 with pneumonia) responded to CDV therapy, as did 25 of 38 (66%) patients who had failed or relapsed after previous preemptive therapy and 15 of 24 (62%) patients in whom CDV was used as the primary preemptive therapy. Of the patients, 21 (25.6%) developed renal toxicity that remained after cessation of therapy in 12 patients. Fifteen patients developed other toxicities that were potentially due to CDV or the concomitantly given probenecid. No toxicity was seen in 45 (61.6%) patients. Cidofovir can be considered as second-line therapy in patients with CMV disease failing previous antiviral therapy. However, additional studies are needed before CDV can be recommended for preemptive therapy.

Functional differences between dendritic cells derived from CD34+ bone marrow and peripheral blood stem cells

BACKGROUND AND OBJECTIVE

It has been previously demonstrated that dendritic cells (DCs) are characterized by an immature stage with high antigen internalization capacity, followed by a mature stage with predominantly immunostimulatory ability. The shift from the immature to the mature state can be induced in vitro by the addition of tumor necrosis factor-a (TNFa). The aim of our study was to investigate the maturation steps of DCs obtained from CD34(+) cells from peripheral blood stem cells (PBSC) and bone marrow (BM).

DESIGN AND METHODS

DCs were generated in vitro from PBSC and BM CD34(+) selected cells. The endocytic activity of the cells was measured by means of dextran-FITC uptake and alloreactivity evaluated with mixed leukocyte reactions. Immunophenotypic analysis was performed by flow cytometry.

RESULTS

We observed that DCs from PBSC, in contrast to the BM derived DCs, were never able to take up soluble antigens. Mixed leukocyte reactions (MLR) performed both on PBSC and BM CD34(+) derived DCs showed an allo-stimulatory activity comparable to normal controls at day 10, but significantly higher at day 14 after the addition of TNFa. Immunophenotypic analysis showed typical dendritic markers in all the samples and, after treatment with TNFa, enhanced expression of co-stimulatory molecules.

INTERPRETATION AND CONCLUSIONS

Our data seem to indicate that, in our culture conditions, BM-derived DCs could be efficiently used for pulsing with specific peptides, while PBSC-derived DCs, being functionally mature, should be more suitable for gene therapy.

Histological alterations in bone marrow in patients with late engraftment after autologous bone marrow transplantation

Bone marrow histology after bone marrow transplantation has rarely been studied. Here, we reviewed the pre- and post-transplant bone marrow biopsies (BMB) of 40 acute myelogenous leukemia (AML) patients autografted in our center, 28 with normal and 12 with delayed peripheral recovery. The two groups were comparable in terms of previous therapy, disease phase and the number of infused cells, and received the same conditioning regimen. In the former group, reduced bone marrow cellularity and mild reticulin abnormalities were usual histological findings; in the latter, five patients had the same pattern, but the other seven had an almost undetectable hematopoietic parenchyma and severe reticulin derangement. One of these seven patients died of reactivated hepatitis B virus infection; the others eventually achieved peripheral recovery, with none of them experiencing a relapse. Autografted AML patients are excellent subjects for histological investigations. They account for the majority of delayed engraftments, the contribution of extramedullary components to the timing of engraftment is minimal, and leukemia relapse cannot be ruled out. These results suggest that BMB is a useful investigation in the work-up of late engraftment. A high degree of reticulin derangement with an almost undetectable hematopoietic parenchyma appear to be the morphological hallmarks of late engraftment.

Blood dyscrasias in clozapine-treated patients in Italy

BACKGROUND AND OBJECTIVE

Clozapine is a dibenzodiazepine derivative that is more effective than standard neuroleptic drugs in refractory schizophrenic patients, but its introduction in some countries was delayed by its propensity to cause blood dyscrasias. However, over the last ten years, different reports have clearly demonstrated that agranulocytosis and neutropenia can be easily prevented by means of strict hematologic surveillance. This article reviews the results of the first five years of the Italian Clozapine Monitoring System (ICLOS).

DESIGN AND METHODS

The hematologic parameters of 2,404 patients registered between 1995 and 1999 were collected in a central database, before the patients began clozapine-treatment, weekly for the first 18 weeks, and then monthly throughout the duration of therapy. On the basis of conventional criteria, different risk levels have been identified with total leukocyte <3. 0x10(9)/L and/or an absolute neutrophil count <1.5x10(9)/L leading to immediate discontinuation of the drug.

RESULTS

The analysis shows that 0.9% of the patients developed neutropenia and 0.7% agranulocytosis, mainly during the first 18 weeks of clozapine treatment. Drug discontinuation led to the normalization of hematologic parameters in all cases, and the use of growth factors reduced the risk of infectious complications. Transient leukocytosis and eosinophilia were also observed but these did not have any serious clinical effects.

INTERPRETATION AND CONCLUSIONS

The ICLOS study confirms that regular hematologic monitoring is highly effective in minimizing the incidence of clozapine-associated blood dyscrasias. The lower than initially expected rates of agranulocytosis and associated deaths are encouraging in view of the benefits of this drug in treatment-resistant schizophrenia and other neurologic disorders.

Syngeneic transplantation in multiple myeloma - a case-matched comparison with autologous and allogeneic transplantation. European Group for Blood and Marrow Transplantation

Twenty-five patients with multiple myeloma received bone marrow grafts (n = 24) or peripheral blood stem cells (n = 1) from twin donors. The outcome was compared in a case-matched analysis to 125 patients who underwent autologous transplantation, and 125 who underwent allogeneic transplantation. Seventeen patients (68%) receiving twin transplants entered complete remission, which was not significantly different from that of autologous (48%) or allogeneic (58%) transplants. The median overall and progression-free survival for the twins was 73 and 72 months, respectively. The overall survival tended to be better (73 vs 44 months) and the progression-free survival was significantly better (72 vs 25 months) than with autologous transplantation and both were significantly better than with allogeneic transplantation. Three of 17 patients who entered complete remission following transplantation had relapsed at follow-up. This relapse rate was significantly lower than following autologous transplantation and similar to the relapse rate with allogeneic transplantation. Only two twins died of transplant-related toxicity. Six further patients died of progressive or relapsing disease. Syngeneic transplantation in multiple myeloma appears to be the treatment of choice if a twin donor is available. A lower relapse risk than in autotransplantation may be due to reinfusion of malignant cells in some patients treated with this modality or to the presence of a graft-versus-myeloma effect in some syngeneic transplants.

The organization of a counselling service for the families of patients undergoing bone marrow transplant

The organisation of our Counselling Service for the relatives of patients undergoing bone marrow transplant is structured in various phases. During the first phase, contact is established with the relatives. The therapist introduces himself to the relatives when the patient is hospitalized and enters the sterile ward. The second phase consists in an illustration of the objectives and purpose of the Service. During this phase, two weekly interviews lasting approximately one hour are proposed, plus assessment tests (CFI, Camberwell Family Interview--and MMPI--Minnesota Multiphasic Personality Inventory). A third phase, which is often contextual to the presentation of the Service, consists in the recognition of the needs and suffering of the given relative. Here, the therapist acts as a receptacle for the anxieties and fear of death brought to him by the subject, thus empathetically accepting these states of mind and legitimizing them. Moreover, our model of intervention envisages the formation of support groups for the relatives of patients suffering from blood cancers. A further phase concerns the exchange of information between the two therapists helping, respectively, the relative and the patient, and also with medical and nursing staff. To further the same aims, for a number of years now, our Service has been organising intervention groups for nursing staff working at CTMO. The final phase is counselling, which takes place twice a week. There are two fundamental areas of intervention that must be taken into account for families of subjects suffering from blood cancers: providing information and offering support. From our experience, it emerges that the relatives need to obtain information on organic aspects of the illness and the transplant.

Cytogenetic and myelodysplastic alterations after autologous hemopoietic stem cell transplantation

Secondary myelodysplastic syndrome/acute myelogenous leukemia (MDS/AML) are today considered a primary complication of autologous hematopoietic stem cell transplantation. In our Center, 83 autografted patients underwent bone marrow (BM) biopsy and cytogenetic analysis at fixed intervals. Twelve patients developed non-clonal cytogenetic abnormalities and 10 patients clonal abnormalities, five of whom (three - 7, one - 5 and one t(9;11)) developed secondary MDS/AML. MDS was also diagnosed in two patients with a normal karyotype. In brief, seven patients (three males, four females; median age 36 years) developed MDS/AML 12-48 months (median 14) after autografting. The FAB diagnosis was AML-M2 in one, chronic myelomonocytic leukemia in two and refractory anemia with excess of blasts in transformation in four cases. Two patients presented a BM biopsy picture of MDS with fibrosis; none of them experienced leukemic transformation. Four MDS patients died, three of leukemic transformation and one of BM insufficiency; the two remaining patients are still living and untransformed. Our data underline the leukemogenic role of previous treatments, even if it is not possible to exclude that underlying disease and/or conditioning therapy may be involved.

Prognostic significance of bone marrow biopsy in essential thrombocythemia

BACKGROUND AND OBJECTIVE

The diagnostic and prognostic value of bone marrow biopsy (BMB) has been widely investigated in patients with chronic myeloproliferative disorders (CMPD). The present study is based on a review of the results of routine BMBs taken from 93 essential thrombocythemia (ET) patients at the time of diagnosis.

DESIGN AND METHODS

The common BMB histologic parameters and clinico-hematologic variables were considered for diagnostic and prognostic purposes. Clinico-pathologic correlations were looked for univariately. Moreover, the diagnostic significance of the histologic findings was tested by means of cluster analysis. Overall survival and event-free survival were considered as prognostic endpoints.

RESULTS

There were no correlations between the clinic and pathologic findings, and none of the histologic and clinical parameters was predictive of survival or the occurrence of major clinical events. Cluster analysis of the BMB findings revealed two distinct morphologic patterns: one was clearly myeloproliferative; the other had somewhat dysplastic features. The event-free and overall survival rates in the latter group were significantly worse (p = 0.0377 and p = 0.0162 respectively), with major ischemic events accounting for most of the difference in event-free survival.

INTERPRETATION AND CONCLUSIONS

These results have no clearcut counterpart in the literature, but we feel that dysplastic BMB findings could be included in the definition of ET prognostic scores in order to allow therapeutic strategies to be adapted to the level of risk.

In vitro effect of clozapine on hemopoietic progenitor cells

BACKGROUND AND OBJECTIVE

Clozapine is a diabenzodiazepine derivative characterized by a high therapeutic index in schizophrenic patients resistant to traditional neuroleptic drugs, because of the rarity of any extrapyramidal side effects, and its particular hematologic toxicity. According to the international literature, clozapine-induced neutropenia occurs mainly during the first 4-6 months of treatment, and its incidence decreases considerably over time. This neutropenic effect is not dose-dependent and normally clears up after drug discontinuation, although it may evolve into agranulocytosis. The aim of this study is to evaluate the in vitro toxic effect of clozapine and N-desmethylclozapine on both committed and immature human hematopoietic progenitor cells.

DESIGN AND METHODS

Cytotoxic assays were performed in vitro on normal human bone marrow samples treated with clozapine or with its metabolite N-desmethylclozapine. The clonogenic potential after treatment with both compounds was assessed on low density mononuclear cells (LD-MNC), purified CD34+ cells, cytokine driven liquid cultures and long term culture initiating cell (LTC-IC).

RESULTS

Clozapine and N-desmethylclozapine had a dose-dependent inhibitory effect on in vitro growth of CFU-GM and BFU-E from normal bone marrow. The two drugs had toxic effects on purified CD34+ progenitor cells but no significant effect on LTI-IC.

INTERPRETATIONS AND CONCLUSIONS

Our data indicate a cytotoxic effect, which is more pronounced with N-desmethylclozapine and at high doses, on the committed progenitor cell compartment but not on primitive hematopoietic cells. Furthermore, our data show that clozapine and N-desmethylclozapine have a direct effect on treated cells and do not induce apoptotic death.

Long-term results in non randomized patients with acute myelogenous leukemia: a single institution experience

Sixty-three non randomized adults with acute myelogenous leukemia were treated with an idarubicin-based protocol. The patients achieving complete remission received autologous bone marrow transplantation or (if > 50 years or refusing autologous bone marrow transplantation) high-dose Ara-C, as late intensification. Fifty-two patients (82.5%) achieved complete remission, 45 after one induction course and 16 of them underwent autologous bone marrow transplantation a median of 11 months later. As of December 1997 (median follow-up 112 months, range 50-135 months), 16 patients were still in complete remission (10 after autologous bone marrow transplantation, 6 after high-dose Ara-C) and 29 had relapsed (median time to relapse 14 months, range 2-75 months). Four patients died in complete remission. The median disease-free survival was 25 months; the 50-months and 10-year disease-free survival were 41% and 35% respectively. No significant differences were observed between the autologous bone marrow transplantation and high-dose Ara-C treated patients whose complete remission had lasted more than 11 months. The median disease-free survival in the autografted patients had not been reached after 120 months (the 50-month and 10-year disease-free survival chances were both 67%). Age was the only predictive variable for leukemic relapse. These long-term results confirm the antileukemic efficacy of an idarubicin-containing protocol, which led to high complete remission rates and favorably influenced disease-free survival. Furthermore, the efficacy of late intensification treatment with either autologous bone marrow transplantation or high-dose Ara-C is underscored. The disease-free survival chances after autologous bone marrow transplantation are comparable with those published for allogeneic bone marrow transplantation; however, disease-free survival of the patients receiving a high-dose Ara-C intensification regimen is not significantly worse than that seen after autologous bone marrow transplantation.

G-CSF after autologous hemopoietic stem cell transplantation in malignant lymphoma

Forty-eight autografted patients were studied after treatment with granulocyte-colony stimulating factor (G-CSF) and were compared with a historical series of 24 patients autografted with bone marrow (BM) without G-CSF. When the patients were divided on the basis of G-CSF administration, type of lymphoma and the source of hemopoietic stem cells, no significant difference was found in the median number of infused BM cells, duration of febrile episodes, platelet and hemoglobin recovery, or in the number of transfusions. The patients receiving peripheral blood (PB) + G-CSF had significantly shorter median durations of antibiotic therapy, hospital stay and polymorphonucleate (PMN) recovery. When the Hodgkin disease (HD) and non-Hodgkin lymphoma (NHL) cases were considered separately, a significant difference between those receiving and those not receiving G-CSF was observed only in the HD group. The advantage offered by PB + G-CSF over BM + G-CSF was far more evident in the NHL group than in HD. It can be concluded that G-CSF improves the outcome of BM transplant in HD, and that the use of PB + G-CSF adds a further advantage; conversely, in NHL, PB + G-CSF is strikingly superior to BM + G-CSF, but the addition of G-CSF adds little advantage.

Expansion of dendritic cells derived from human CD34+ cells in static and continuous perfusion cultures

We examined the effects of different cytokine combinations and culture conditions on the expansion and modulation of cell surface antigens of CD34+ derived dendritic cells (DCs), the most efficient antigen-presenting cells capable of stimulating resting T cells in the primary immune response. Cells with a dendritic morphology and expressing HLA-DR, CD1a, S100 and CD83 were maximally expanded under serum-free conditions with the addition of SCF, GM-CSF, TNF-alpha, TGF-beta and Flt-3 ligand (fold increase of CD1a+ cells = 102 +/- 32 after 2 weeks of culture). CD34+ cells were also grown under continuous flow conditions in an artificial capillary system: after 14d of culture, the expansion in the total cell number was lower than that of the static cultures (3.3 +/- 2 v 18.9 +/- 4) but the percentage of CD1a+/CD83+/ CD80+ cells was considerably higher, whereas the CD14+ cells were significantly reduced (8.9 +/- 2 v 26 +/- 13). In continuous perfusion cultures, low levels of DC precursors and of LTC-IC were still present up to day 14. The DCs generated under flow conditions stimulated the mixed leucocyte reaction (MLR) more than the cells grown in static cultures. By electron microscopy, cells grown in the continuous flow system showed an increased number of large cells with numerous dendritic processes and abundant multilamellar complexes. The cells expanded under these conditions were sorted on the basis of their light-scatter properties into two fractions: one containing a predominance of CD1a+/S100+/ CD8 3+/CD80+/CD14- 'large cells' with great internal complexity (mature DCs); the second including 'small cells' either CD33+/CD14+, CD33+/CD15+ or CD33+/CD13-/CD14. The DCs generated and selected with this method are therefore particularly well suited for immunotherapeutic protocols.

Haematopoietic abnormalities after autologous stem cell transplantation in lymphoma patients

Haematopoietic reconstitution after autologous stem cell transplantation (ASCT) was evaluated at different times in 26 lymphoma patients. All of the patients showed a significant decrease in the number of both committed (CFU-C) and more primitive progenitor cells (LTC-IC). The expansion of bone marrow progenitor cells in a 'stroma-free' long-term liquid culture system supplemented with SCF, IL-3, IL-6 and GM-CSF from 19 transplanted patients was significantly reduced compared to normal controls. The stromal cell compartment, evaluated by means of a CFU-F assay, was also greatly reduced. The number of haematopoietic and stromal cell progenitors was, nevertheless, very similar to their pre-transplant values. Bone marrow histology, which was evaluated at different times after transplant, showed an increase in reticulin fibres, the dilatation of parenchymal sinusoids and some morphological evidence of trilineage dysplasia in 11 patients; however, the same abnormalities were seen in the majority of pre-transplant samples. No cytogenetic abnormalities were observed in 15 patients before transplant, but four subsequently developed persistent clonal karyotypic alterations and five showed non-clonal abnormalities that generally disappeared over time. Our data suggest that both the stromal and the haematopoietic compartments are somehow damaged after ASCT for lymphoma; however, these defects generally pre-exist the transplant conditioning regimen and seem to become less pronounced over time.

The diagnostic and prognostic value of bone marrow immunostaining in myelodysplastic syndromes

Immunohistochemistry has been introduced as a means of increasing the diagnostic accuracy of bone marrow biopsy (BMB) in myelodysplastic syndromes (MDS); more recently the possibility of coupling immunostaining with other investigational techniques has broadened the spectrum of applications to the biology and physiopathology of MDS. Using panels of monoclonal antibodies (MoAbs), various histological classifications of MDS have been proposed as an alternative to the FAB criteria. The use of lineage-specific MoAbs has allowed a deeper insight into the dysplastic features of early hematopoietic precursors. The study of various gene products involved in the regulation of cell growth, proliferation and sensitivity to antineoplastic drugs, has revealed significant differences between MDS and morphologically-related disorders, particularly acute myelogenous leukemias (AML); these can be considered markers of a biological difference between the two groups of disorders and deserve consideration when designing therapeutic strategies for MDS. Both an increase in the percentage of cell positivity for the CD34 glycoprotein and a tendency of positive cells towards forming aggregates have been shown to be reliable predictors of leukemic transformation and survival, irrespective of the FAB subtype; furthermore, CD34 positivity has also proved to be a better prognostic factor than the presence of the abnormal localization of immature precursors (ALIP) on BMB. Finally, the simultaneous occurrence of "large" and CD34 positive aggregates can be proposed as a means of recognizing MDS patients with an exceedingly unfavourable prognosis, and who are therefore suitable for early aggressive therapy.

Fibrillary glomerulonephritis in Castleman's disease

Castleman's disease is an uncommon lymph node disorder which can be associated with renal disease. In this report we describe a patient with fever, weight loss, anorexia, increase in inflammatory proteins, anemia and nephrotic syndrome. Castleman's disease, plasma cell type, was diagnosed by histologic analysis after surgical excision of a pelvic lymph node. The disease was considered localized, since further investigations did not show any other pathologic mass. After resection of the pelvic lymphoid mass, clinical remission of systemic symptoms and laboratory abnormalities was observed, with the exception of the nephrotic syndrome. Renal biopsy was performed and showed a pattern compatible with fibrillary glomerulonephritis. Progressive decline in renal function was observed, despite immunosuppressive therapy.