Multilineage hematopoietic engraftment after allogeneic peripheral blood stem cell transplantation without conditioning in SCID patients.

Successful stem cell transplantation for patients with severe combined immunodeficiency (SCID) from matched family donors without conditioning results in engraftment of T lymphocytes. B lymphocytes engraft in only 50% of the cases, while myelopoiesis and erythropoiesis remain of host origin. Full hematopoietic engraftment was reported in one case after bone marrow transplantation without conditioning for a SCID patient. We studied three SCID patients who were transplanted with unmodified mobilized peripheral blood from HLA-identical family sex-mismatched members. They received megadoses of stem cells (18-23 x 10(6)CD34/kg). In contrast to the expected mixed chimerism that usually occurs in the absence of conditioning, we found in our patients 100% donor cell engraftment based on fluorescence in situ hybridization (FISH) and microsatellite techniques. Subset analysis of the engrafted cells using a multiparametric system enabling a combined analysis of morphology, immunophenotyping and FISH showed that both T and B lymphocytes and myeloid cells were of donor origin in two patients, while T lymphocytes and myeloid cells were of donor origin in the third. In the two cases with ABO incompatibility, erythroid engraftment was evidenced by blood group conversion from recipient to donor type. Multilineage donor engraftment is possible in SCID patients even without conditioning.

Tetraploid myeloid cells in donors of peripheral blood stem cells treated with rhG-CSF.

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is frequently used to mobilize CD34+ cells in healthy donors and patient with malignant diseases prior to peripheral blood stem cell (PBSC) harvest. To analyze the effects of rhG-CSF on morphology and genotype of white blood cells, a novel multiparametric cell scanning system that combines morphologic, immune and genotypic analyses of the same cells was used. We report here that tetraploid myeloid cells are present in the peripheral blood of donors treated with rhG-CSF. The tetraploidy was detected in up to 0.6% of differentiated myeloid cells and all observed CD34+ cells were diploid. Thus, short treatment with rhG-CSF of PBSC donors induces numerfical chromosomal alterations in a small subset of mature myeloid cells.

Chimerism testing and detection of minimal residual disease after allogeneic hematopoietic transplantation using the bioView (Duet) combined morphological and cytogenetical analysis.

Recurrent disease remains a major obstacle to cure after allogeneic transplantation. Various methods have been developed to detect minimal residual disease (MRD) after transplantation to identify patients at risk for relapse. Chimerism tests differentiate recipient and donor cells and are used to identify MRD when there are no other disease-specific markers. The detection of MRD does not always correlate with relapse risk. Chimerism testing may also identify normal hematopoietic cells or other cells not contributing to relapse. In this study we report our initial experience with a novel system that provides combined morphological and cytogenetical analysis on the same cells. This system allows rapid automatic scanning of a large number of cells, thus increasing the sensitivity of detection of small recipient population. The clinical significance of MRD detection is improved by identifying the morphology of recipient cells. Identification of recipient characteristics within blasts predicts overt relapse in leukemia patients and precedes it by a few weeks to months. Identification within mature hematopoietic cells may not be closely associated with relapse. The system also allows chimerism testing after sex-mismatched transplants, within cellular subsets, with no need for sorting of cells. The system merits further study in larger scale trials.

Spontaneous regression of congenital leukaemia with an 8;16 translocation.

Congenital leukaemia (CL) is a rare disorder that presents with extramedullary infiltrates and a myeloid phenotype. CL can progress rapidly without adequate treatment, but, paradoxically, may also remit spontaneously. Because of the significant toxicity involved in delivering chemotherapy to newborns, it is important to identify those newborns who may not require treatment. We describe an infant who presented at 1 week of age with congenital myeloid leukaemia. Cytogenetic analysis revealed a t(8;16)(q11;p13) translocation. The infant's leukaemia underwent a spontaneous regression. This case further confirms the possibility of spontaneous remission in congenital leukaemia. Moreover, it suggests that the presence of a clonal cytogenetic aberration does not preclude the possibility of a spontaneous regression in CL.

Amplification of immunological functions by subcutaneous injection of intermediate-high dose interleukin-2 for 2 years after autologous stem cell transplantation in children with stage IV neuroblastoma.

BACKGROUND: Immunotherapy given post-autologous stem cell transplantation may eliminate residual tumor cells escaping the conditioning protocol. METHODS: Five children suffering from stage IV neuroblastoma were treated by recombinant interleukin-2 (IL-2) post-autologous peripheral blood stem cell transplantation. The patients' peripheral mononuclear cells were monitored for CD3+ and CD56+ levels, their proliferative response and killing of various cell lines targets. RESULTS: An increase in the level of total lymphocytes, mainly due to expansion of T cells, and enhanced proliferative response to phytohemaglutinin were observed. Elevated cytotoxicity against K562 and neuroblastoma target cells was detected in four patients and against K562 targets in one patient. Toxicity included mild thrombocytopenia, and fever in four patients and mild to moderate encephalopathy which necessitated withdrawing one patient from the protocol. Three of five patients studied are alive today, one of them whose IL-2 was stopped, is in relapse. Two patients have died. CONCLUSIONS: Immunotherapy with s.c. intermediate-high dose IL-2 is feasible and results in expansion of T cells and in stimulation of killing activity against several targets including in some cases, neuroblastoma tumor cells.

Neutropenia as a complication of intravenous immunoglobulin (IVIG) therapy in children with immune thrombocytopenic purpura: common and non-alarming.

UNLABELLED: Following reports on adult patients with neutropenia as a result of administration of intravenous immunoglobulin (IVIG) we have investigated the incidence and consequences of neutropenia following IVIG treatment in children with immune thrombocytopenic purpura (ITP). The medical records of 14 children with ITP who received IVIG as inpatients were reviewed. Past and present history, age, previous medications, complete blood count and differential before and after treatment with IVIG were recorded for each patient. The patients, aged 5.5 +/- 3.5 (0.5-11.5) years [mean +/- SD; range] received one or more courses of IVIG. Neutropenia (total neutrophils < 2000/mm3) was observed within 24 h after the first course of IVIG in five children (36%). The pretreatment neutrophil count in this group was not significantly different from that observed in the patients without IVIG-induced neutropenia (p = 0.98). The condition resolved spontaneously and without complications in all patients within 48 h. In a preliminary experiment in which bone marrow derived mononuclear cells were assayed for the clonogenicity in methylcellulose, there was no suppressive effect of IVIG on the number of CFU-GM colonies. CONCLUSIONS: Since IVIG is currently administered in a vast number of medical indications, neutropenia following IVIG administration may not be an uncommon finding. It seems to be transient and self limited.

Successful human umbilical cord blood stem cell transplantation without conditioning in severe combined immune deficiency.

A 2-month-old girl with severe combined immunodeficiency (SCID), presented with mild staphylococcal skin infection, lymphopenia, low T cell number, absence of B cells, high number of NK cells, and a negligible response to mitogens. Since her older brother died as a result of SCID 2 years earlier, cord blood was harvested from a sister born 2 1/2 years earlier, who was normal and fully matched both by serology and molecular typing. In view of her clinical condition and in spite of a high number of NK cells with normal activity, HUCBT without preparative conditioning was performed. No G-CSF was administered. Engraftment with mixed chimerism was evident 3 weeks post transplantation. There were no peritransplantation complications. Eighteen months post transplantation, the girl is in excellent condition, blood counts are normal, T cell engraftment is complete, B cell engraftment is proceeding gradually, and the mitogen stimulation tests are normal. Due to the unique nature of HUCB hematopoietic cells, engraftment without conditioning may be possible in patients with SCID with fully matched donors. This is the first HUCBT performed without conditioning.

A photodynamic pathway to apoptosis and necrosis induced by dimethyl tetrahydroxyhelianthrone and hypericin in leukaemic cells: possible relevance to photodynamic therapy.

The mechanism of cell death induction by dimethyl tetrahydroxyhelianthrone (DTHe), a new second-generation photodynamic sensitizer, is analysed in human leukaemic cell lines in comparison with the structurally related hypericin. DTHe has a broad range of light spectrum absorption that enables effective utilization of polychromatic light. Photosensitization of HL-60 cells with low doses of DTHe (0.65 microM DTHe and 7.2 J cm(-2) light energy) induced rapid apoptosis of > or =90% of the cells. At doses > or =2 microM, dying cells assumed morphological necrosis with perinucleolar condensation of chromatin in HL-60 and K-562 cell lines. Although nuclear fragmentation that is characteristic to apoptosis was prevented, DNA digestion to oligonucleosomes proceeded unhindered. Such incomplete apoptosis was more prevalent with the related analogue hypericin throughout most doses of photosensitization. Despite hypericin being a stronger photosensitizer, DTHe exhibited advantageous phototoxic properties to tumour cells, initiating apoptosis at concentrations about threefold lower than hypericin. Photosensitization of the cells induced dissociation of the nuclear envelope, releasing lamins into the cytosol. DTHe also differed from hypericin in effects exerted on the nuclear lamina, causing release of an 86-kDa lamin protein into the cytosol that was unique to DTHe. Within the nucleus, nuclear envelope lamin B underwent covalent polymerization, which did not affect apoptotic nuclear fragmentation at low doses of DTHe. At higher doses, polymerization may have been extensive enough to prevent nuclear collapse. Hut-78, CD4+ cells were resistant to the photodynamically activated apoptotic pathway. Beyond the tolerated levels of photodynamic damage, these cells died exclusively via necrosis. Hut-78 cells overexpress Bcl-X(L) as well as a truncated Bcl-X(L)tr isoform that could contribute to the observed resistance to apoptosis.

[Hemophagocytic syndrome].

Hemophagocytic syndrome is a rare, fulminant disease characterized by generalized histiocytic proliferation associated with phagocytosis of erythrocytes, platelets, and to a lesser extent, of white blood cells. We report a 2-year-old boy admitted with high fever and irritability, with a rash, marked hepatomegaly and generalized lymphadenopathy. Liver function tests were abnormal and there was thrombocytopenia and hyperlipidemia. Bone marrow aspiration revealed hemophagocytosis. Despite intensive treatment with steroids, intravenous immunoglobulin and cytotoxic drugs, he died within 10 weeks.

Association between hyperflexibility of the thumb and an unexplained bleeding tendency: is it a rule of thumb?

A bleeding tendency manifested by petechiae and ecchymoses is one of the most common causes for referral of patients to haematology clinics. Vessel wall pathology is not usually considered to be a cause for deranged haemostasis, although coexistence of increased capillary fragility and joint hypermobility have been reported. We determined the frequency of thumb hyperextensibility and scored the findings in a series of 44 patients referred because of ecchymoses and petechiae, as well as 261 control children and their mothers. All 44 patients had normal coagulation studies. Thumb flexibility score was +4 in 30 patients, +3 in eight patients, +2 in five patients and +1 in one of the index patients. In the control group, only one of 261 had a +4, and three had a +3 score, and two of 260 mothers had a +4 score. Ecchymoses were not observed in any of these subjects, nor in the +1 patients. Based on clinical presentation and normal coagulation studies, we suggest that our patients had an underlying subtype of Ehlers-Danlos syndrome. In view of the dramatically high occurrence of thumb hyperextensibility in patients with unexplained mild bleeding tendency, costly haemostatic and coagulation studies on such patients may not be necessary.

Chromosomal translocation (1:13) in a case of alveolar rhabdomyosarcoma.

PURPOSE: To describe a patient with a variant translocation (1;13)(p36;q14) in an alveolar rhabdomyosarcoma and compare the clinical course with four other cases. PATIENTS AND METHODS: A 10-year-old girl presented with multiple masses involving the thigh, abdomen, chest wall, and scalp with pleural effusion and edema of the lower extremities. RESULTS: A bone marrow biopsy, aspirate, and biopsy of the thigh mass all showed tumor invasion. Histopathology and cytogenetics of the thigh mass revealed an alveolar rhabdomyosarcoma with a t(1;13)(p36q14) variant. There was no response to aggressive therapy and the patient died within 3 weeks of admission. CONCLUSION: Variant t(1;13)(p36;q14) has now been described in 5 cases of rhabdomyosarcoma, and may define a subset of patients with extensive disease at diagnosis unresponsive to current therapeutic modalities.

Helicobacter pylori-associated gastric lymphoma in a girl.

We present a case of a 14-year-old girl with gastric large cell lymphoma. The girl's lymphoma was characterized by the presence of mucosa-associated lymphoid tissue. Infection with Helicobacter pylori (HP) was ascertained at the time of diagnosis. The girl was successfully treated by a combination of chemotherapy (MACOP-B) and anti-HP drugs (omeprazole plus amoxicillin). Thrombus of the inferior vena cava, a rare complication, evolved during treatment.

Central nervous system involvement at diagnosis in a case of pediatric CD30+ anaplastic large cell lymphoma.

Central nervous system (CNS) involvement in Ki-1/CD30 lymphoma is extremely rare, in contrast to the frequent involvement in other types of pediatric non-Hodgkin's lymphoma. No mechanism has yet been proposed to explain the sparing of the blood brain barrier in Ki-1/lymphoma. We present a 2-year-old boy who was admitted to the Department of Pediatric Hemato-Oncology due to lethargy, progressive breathing difficulties, massive diffuse lymphadenopathy, hepatosplenomegaly, and ichthyosis-like skin involvement with epidermolysis. A lymph node biopsy was compatible with Ki-1/CD30 anaplastic large cell lymphoma (ALCL). Bone marrow aspirate and biopsy demonstrated reactive hyperplasia. Cytogenetic analysis displayed hyperdiploid cells with 1p(-) in most cells. Cerebrospinal fluid examination showed pleocytosis with CD30+ cells. Possible mechanisms which could enable CNS involvement in this unusual case are discussed.

Protection of human myeloid leukemic cells against doxorubicin-induced apoptosis by granulocyte-macrophage colony-stimulating factor and interleukin 3.

Hematopoietic cells require certain cytokines to maintain viability by preventing apoptotic cell death. These cytokines can also protect leukemic cell lines against induction of apoptosis by cytotoxic anticancer compounds. We now show that the cytokines granulocyte-macrophage colony-stimulating factor and interleukin 3 can protect primary human myeloid leukemic cells against doxorubicin-induced apoptosis. Protection was detected in cells from 72% of the myeloid leukemic patients tested. The results indicate that these, and perhaps other, hematopoietic cytokines can decrease the effectiveness of cytotoxic anticancer therapy in some human myeloid leukemias. Leukemic cell sensitization to cytotoxic therapy may, therefore, require decreasing the availability of certain cytokines.

Two embryonal cancers after in vitro fertilization.

BACKGROUND: In vitro fertilization is not considered to be associated with an increased rate of pediatric malignancies, and only three have been reported in the literature. Two additional rare pediatric tumors in children conceived through this technique are reported. METHODS: Two children 12 and 18 months of age, developed hepatoblastoma and clear cell sarcoma of the kidney, respectively. They were both products of uneventful pregnancies induced by in vitro fertilization. No other environmental, prenatal, or family factor was found. RESULTS: The first child died after a failed remission induction with cisplatin, doxorubicin, and vincristine, whereas the second child is alive with no evidence of disease 18 months after diagnosis and treatment according to NWTS protocol. CONCLUSIONS: A possible association between in vitro fertilization and pediatric malignancies is suggested.