A case of transfusion-related acute lung injury (TRALI) due to HLA antibodies present in one unit of packed red blood cells led us to discuss the screening of HLA antibodies for female donors having been pregnant, and the use of labile blood products.

Chemokines are a large family of cytokines that act not only as immune and inflammatory regulators but also as regulators of hematopoiesis. Two major subfamilies of chemokines are distinguished on the basis of whether the first two cysteines are separated by a single residue (CXC) or three residues (CX3C) or they are adjacent (CC) or there is a single C. The Macrophage Inflammatory Protein 1 alpha (MIP-1 alpha), which belongs to CC family is a powerful inhibitor of hematopoisis in vitro and in vivo. The sub-family CXC comprises two main groups. The first sub-group includes the ELR chemokines, in which interleukin-8 (IL-8) is the most prototypic and possesses suppressive activities on hematopoiesis. Platelet Factor 4 (PF4) belongs to the sub-group of non-ELR CXC chemokines. PF4 acts as an inhibitor of hematopoiesis, particularly of the megakaryocytopoiesis. Recently, it has been shown that a peptide of PF4, 34-58 which does not contain the site of heparin binding, is able to inhibit the growth of hematopoietic progenitors in vitro, providing evidence for a model of heparin dependent and independent pathways of PF4 action on hematopoiesis. PF4 can reduce the chimiosensitivity of hematopoietic cells in mice treated by the cytotoxic drug 5-Fluorouracyl, suggesting a potential clinical application of PF4 in cancer therapy.

The precise role of the different proteins that constitute the renin-angiotensin and kallikrein-kinin systems in the development of hypertension and some cardiac and renal diseases remains unclear. Genetic manipulations in animals is a powerful approach that provide the opportunity to explore the role of each of these proteins in vivo. Indeed it is possible in the rat and in the mouse to manipulate a specific gene without modifying the other genetic and environmental factors. A causal link can thus be established between the gene and a physiologic or pathologic alteration. The possibilities are either the overexpression of the gene in all or in specific tissues (transgenesis), or the modification (often the inactivation) of the endogenous gene by homologous recombination. The second technique has the advantage to be more specific but it can be used only in the mouse; it is performed by transfecting totipotent embryonic stem cells with a vector harboring identical sequences to those of the gene to be targeted. The embryonic stem cells are then injected into embryos in which they will participate in the generation of the different organs including the gonads. The resulting chimeric animals can therefore transmit the mutation to their offspring creating a new genetically modified mouse strain. Many strains targeted in the different components of the renin-angiotensin and kallikrein-kinin systems have been generated in this way. These animal models should allow to test many physiopathological hypotheses that have been put forward from the results of human genetics and clinical studies, and also to raise new ones.

Testicle germ cells tumors are the most common young men neoplasm. The incidence is maximal in Scandinavian countries. Cryptorchidism is a predisposing factor. Diagnosis is clinic, first treatment is radical orchidectomy by inguinal incision, after study of tumor markers. Histology shows seminoma or non seminomatous tumor. Carcinoma in situ is the precursor of invasive germ cell tumors. Germ cell tumors have no p53 mutation, and have isochrome of the short arm of chromosome 12 as a specific marker. With the results of histological, biochemical and radiographic evaluation, patient are classified as follows: good, intermediate and poor risk prognosis. Standard treatment of stage I seminoma is prophylactic irradiation. Stage II with less than 3 cm lymph node too. Other situations need a cisplatin based chemotherapy. In case of metastatic residuals masses more than 3 cm, surgery need to be discussed. Stage I non seminomatous germ cell tumors are treated by retroperitoneal lymphadenectomy, by surveillance or by two cycles of adjuvant chemotherapy with cisplatin, etoposide and bleomycin (BEP). Standard treatment of good prognosis stage II and III is three cycles of BEP, four for poor prognosis. Residual mass need surgery, adjuvant chemotherapy is necessary in presence of viable germ cell. Standard treatment for relapses is chemotherapy with cisplatin, ifosfamide and vinblastine with a 30% remission rate. The place of high dose chemotherapy with autologous stem cell transplantation is not yet standardised. New drugs, as paclitaxel, are under studies.

It has been well shown that apoptosis occurs in mammalian embryos as early as the blastocyst stage, in order to regulate the importance of the inner cell mass. We have looked for apoptosis at the cleavage stage, in human embryos that could not be transferred because of a high degree of fragmentation (grade IV) or a blockage in embryo development. Most of these embryos had blastomeres with condensed or fragmented chromatin, evocating apoptosis. Two markers of programmed cell death, detecting either early (Annexin V) or late (TUNEL technique) apoptosis events, were positive in our study: 100% and 30% of embryos were marked by Annexin V and TUNEL, respectively. Therefore, it seems that apoptosis occurs very early in human embryos conceived in vitro; this could represent a response to suboptimal culture conditions.

The store of primordial follicles used for folliculogenesis is formed during oogenesis. Its size is the consequence of three processes: oogonia multiplication, time of meiosis initiation and extent of loss of germ cells (atretic oogonia, oocytes at the pachytene stage and newly formed primordial follicles). Apoptosis is causing this loss but its mechanisms are poorly documented. Both death signals (TNT alpha, Fas ligand) and survival signals (LIF, kit ligand) are present in the embryonic gonad. The apoptotic cascade then involves bclz, bax and caspases since knock out of these genes alters the store of primordial follicles. Apoptosis also exists within primordial follicles in adult ovaries and involves oocyte death. Its control has not been extensively studied.

In Hodgkin's disease, cases of resistance to initial treatment and of recurrence have a low probability of cure. Remission of less than one year and disseminated stage are the two main prognostic factors. In favourable cases (late recurrence or localised stage), conventional chemotherapy, associated or not with radiotherapy, can be suggested. In case of early relapse or disseminated stage, intensified treatment followed by autografting of hematopoietic line cells should be considered. In highly unfavourable cases associating early relapse and dissemination, to which refractory cases can be added, new therapeutic strategies should be evaluated in prospective studies.

Treatment strategy is based on prognosis groups although there is no consensus on their definition. In stages IIIA with unfavorable factors and stages IIIB or IV without high risk factors, chemotherapy alone or followed by irradiation is used. To reduce toxicity, radiation therapy on bulky disease and residual masses is preferred to extended fields. Indications for intensive chemotherapy with autograft of hematopoietic stem cells as initial treatment for high-risk patients must be determined with therapeutic trials.

Amongst the various causes of anemia in systemic lupus erythematosus, isolated and acquired erythrocyte dysplasia is rare and most often part of global dysmyelopoiesis.

The availability, in the mouse, of embryonic stem cells (ES cells) which have the ability to colonize the germ line of a developing embryo, has opened entirely new avenues to the genetic approach of embryonic development, physiology and pathology of this animal. Indeed, it is now possible, using homologous recombination in ES cells, to introduce mutations in any gene as long as it has been cloned. Thus, null as well as more subtle mutations can be created. Furthermore, scenarios are currently being derived which will allow one to generate conditional mutations. Taken together, these methods offer a tremendous tool to study gene function in vivo; they also open the way to creating murine models of human genetic diseases.

Somatic gene therapy is defined as the transfer of a heterologous gene into an organism for the purpose of correcting a genetic defect or providing a new therapeutic function to the target cell and thus inducing a cure or improving associated symptoms. While encouraging results have been generated by recent clinical evaluation of combination of anti-viral drugs, Aids still constitute an obvious candidate among the infectious diseases which might be treated by gene therapy. We have therefore chosen to develop and evaluate a gene therapy strategy based on the transfer into human target cells of HIV1-inducible interferon (IFN) alpha, beta or gamma genes. In a preliminary study, myeloïd U937 cell lines transfected with expression vectors containing the IFN alpha, beta or gamma genes under the control of the long terminal repeat (LTR) sequences of HIV1 were shown to be strongly resistant against an in vitro and in vivo (in HIV1 challenged SCID mice model) HIV1 infection. This cellular resistance was correlated with a strong induction of transgenic IFN synthesis and for IFN gamma, with a defect of HIV particles maturation. Secondly, construction and production of high titer retroviral vectors containing Tat-inducible IFN genes allowed efficient transduction of lymphoïd cell lines and human primary lymphocytes. These transduced cells were shown to be highly resistant against laboratory and primary HIV isolates. Taken together, our in vitro and in vivo results suggest that HIV1 inducible IFN gene therapy can be beneficial to HIV-infected individuals provided the fact that methods are developed that allow the efficient transduction of human hematopoïetic stem cells.

Modern molecular haematology is characterized by the great strides made in the use of cytokines, especially haematopoietic growth factors. These factors constitute a heterogeneous group of molecules that ensure the survival, proliferation and differentiation of the haematopoietic cells. Present detailed knowledge of the structure of the main haematopoietic growth factors and their receptors, and of the cloning and sequencing of their genes, permits the use of genetic engineering to produce recombinant human growth factors whose therapeutic applications have raised very great hopes for clinical haematology. Data obtained from several clinical studies have allowed the use of some of these molecules in France. This is the case concerning erythropoietin (Eprex, Recormon), G-CSF (Neupogen, Granocyte) and GM-CSF (Leucomax), each with specific uses. Others haematopoietic growth factors, such as stem cell factor (SCF) are presently evaluated for their clinical interest. Finally, interleukin 3 (IL3), whose in vitro activities seemed to be of potential interest, has been evaluated during clinical studies. Its toxicity and lack of specificity have been evidenced and do not allow its present utilization. The first part of this review is focused on the general structure and biological activity of haematopoietic growth factors and presents the actual therapeutic field of the use of erythropoietin and the promising application of recombinant thrombopoietin.

The CHOP regimen (cyclophosphamide vincristine, adriamycin, prednisone) is considered since twenty years as the standard treatment of disseminated aggressive non-Hodgkin's lymphomas and cures approximately 30% of patients. More recently, intensive chemo(radio)therapy followed by rescue with bone marrow or blood hematopoietic stem cells has become the standard treatment of chemosensitive relapses of aggressive non-Hodgkin's lymphomas. Consequently, two questions with practical applications have arisen and are discussed in this review: Is it justified to increase the dose intensity of chemotherapy, using either single treatment intensification with stem-cell rescue, or sequential intensified chemotherapies, especially in cases with adverse prognostic factors? On the contrary, is a decrease in treatment intensity compared to CHOP chemotherapy, especially in elderly patients, harmful to the patient?

We report a case of intravascular malignant lymphomatosis observed in a 71 year-old male and characterised by the presence of a proteinuria in relation to the specific intraglomerular localisation. This malignant lymphoma, usually of the B phenotype, is rare and affects predominantly the central nervous system and the skin. Neoplastic cells home selectively to endothelium. Histological renal infiltration is frequent but a glomerular localisation, with proteinuria, is rare. The mechanism whereby lymphocytes home to endothelium cells is unclear but it could be related to the expression of lymphocyte-endothelium adhesion molecules. When present the nephrotic syndrome is associated with minimal change disease.

Cells contained in umbilical cord blood collected after birth can be cryopreserved and used for hematopoietic stem cells transplantation in patients with severe hematological disorders. The first success has led to the development of cryopreserved umbilical cord blood banks. More than 500 cord blood transplant have been reported and more than 10,000 cord blood have been stored for use in unrelated and related matched and mismatched transplants. European results show that the number of hematopoietic stem cells present in one cord blood is sufficient to permanently engraft most of the patients. Graft versus host disease is decreased even in unrelated mismatched transplants.

Hematopoietic progenitor cells are present in umbilical cord blood; placental blood (PB) previously considered as waste product now constitutes an alternative source of hematopoietic stem cells for bone marrow reconstitution. This has promoted the establishment of cord blood banks for use in unrelated transplants. The banking of PB offers many advantages: the donors do not require anesthesia, stored PB can be a valuable source of stem cells for patients from ethnic minorities underrepresented in volunteer registers, and stored PB can be made available much faster than bone marrow from unrelated donors. Preliminary clinical experience suggests that, due to the immunological immaturity of PB cells, graft versus host disease might be lower than when using bone marrow from adult donors and HLA restrictions might be less stringent. If the number of nucleated cells in PB often appears low for patients weighing more than 40 kg, clinical data suggest that the number of stem cells may be sufficient for adult transplantation. The number of cord blood banks throughout the world is increasing rapidly. In the USA and Europe, more than 10,500 PB units are stored and available for transplantation. In the next 5 years, a total of 50,000 PB will be reached which may be sufficient to provide for the majority of candidates for unrelated BM transplantation. The practices of umbilical cord blood collection, mother selection, infectious disease screening, cell manipulation and storage must be standardized. Some accreditation process should be mandatory for assessing operating procedures and the quality assurance programs of the banks, and for allowing the international exchange of placental blood between transplant centers.

Dendritic cells (DC) are the most potent antigen-presenting cells. Thus, ex vivo antigen-pulsed DC are a potentially powerful tool to induce in vivo immunity against tumor-associated or viral antigens. Therefore, culture methods to generate high numbers of DC from bone marrow or blood CD34+ hematopoietic progenitor cells have recently been developed. These methods, which use different combinations of growth factor--mainly granulocyte/macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-alpha and interleukin (IL)-4--make the characterization of DC obtained from CD34+ cells of different origins easier and allow to assess whether DC relate to a unique or distinct differentiation pathways. Monocytes and even macrophages can also directly differentiate into DC in the presence of GM-CSF and IL-4. This has to be reconciled with evidence supporting earlier branching off of the macrophage and DC lineages, and raises questions as to the identity of the latter lineage. Apart from DC of myeloid origin, DC may also originate from lymphoid progenitors. Because the capacity of DC to capture, process and present antigens is known to vary according to their differentiation stage, and lymphoid DC might behave differently from lymphoid DC in this respect, the definition of which type of DC to use for immunotherapy must be more precise, in order to avoid detrimental side effects or results. From a practical point of view, it is also necessary to define the most appropriate cytokine combinations and schedules thereof to optimize proliferation and differentiation of DC from different origins. These conditions should then be applied to generated DC for their efficient and safe use for clinical immunotherapy.

We evaluated the reliability of a flow cytometry technique for counting mononuclear cells (MNCs) in cytapheresis products. Eighty freshly-prepared samples of peripheral stem cells were studied using a dual immunolabeling technique with antibodies to CD13/CD14, and were also labeled with anti-CD34. Results of this immunophenotype determination were compared to those of the conventional method for counting MNCs under the microscope. Dual CD13/CD14 labeling was found to be a simple and reliable method for counting MNCs in the presence of immature and stimulated cells. When used in combination with CD34 labeling, the dual immunolabeling method helped improve the evaluation of the quality of peripheral stem cell grafts.