Nouvelle revue francaise d'hematologie最新文献

A total of 458 eight blood cell counts, accompanied by blood film reviews of the same samples, were performed with an electronic cell counter and with the QBC. In the great majority of cases, the QBC gave fast and accurate control of the flags from the electronic counter, thus avoiding the necessity for manual validation with its associated risks of infection and contaminations. Furthermore, QBC non readability could be related to microcytosis and hypochromia and hence point to possible cases of congenital or acquired haemoglobinopathy.

Correlations between different peripheral blood parameters and harvesting yields of stem cells were analysed in 230 leukaphereses performed on 61 patients. According to multivariate analysis, the number of circulating CD34 positive cells was found to provide the best preleukapheresis parameter for predicting the quality of peripheral blood progenitor cell harvest. A high correlation coefficient and small 95% confidence and prediction intervals would indicate the assay of CD34 positive cells in peripheral blood to be a unique tool essential for monitoring the collection of circulating haematopoietic progenitors.

Autologous stem cell transplantation has increased in France over the last five years, mainly due to a marked increase in the number of autologous peripheral blood progenitor cell (PBPC) transplants, which represented about 66% of autologous transplants performed in 1994. This increase is related to the more rapid engraftment observed after PBPC transplantation than after bone marrow transplantation (BMT). The rate of haematopoietic recovery is significantly influenced by the dose of CFU-GM infused, by use of haematopoietic growth factors for mobilization and to a lesser extent after transplantation and by types of conditioning regimens. However, the outcome of patients does not seem to differ following PBPC as compared to bone marrow transplantation.

Culture of human hematopoietic progenitors on a large scale could lead to several clinical applications within the near future, including the production of differentiated and functional cells, the increase in the number of early progenitors, especially stem cells, with such use as gene transfer, or the improvement of grafts used to limit the hematological toxicity associated with high-dose chemotherapy. In this case, one can still distinguish different objectives: improvement of grafts that contain low numbers of progenitors because of prior chemotherapies or because of marrow involvement for example, and qualitative changes in the graft content that would allow to envision the disappearance, or the further reduction, in the duration of absolute neutropenia that follows delivery of high dose chemotherapy ("nadir rescue"), despite substitution of mobilized blood cells to marrow cells and the in vivo use of hematopoietic growth factors. Additional advantages may be related to tumor purging in autologous expanded cells, and to the change in the ratio between hematopoietic progenitors and immunocompetent cells in allogeneic expanded populations. Therefore it appears that in vitro expansion currently raises two types of questions: the first ones are related to the definition of clinical or biological endpoints to be achieved, the second ones are related to "bioengineering", and deal with the efficiency and safety of progenitor cell cultures to be used for clinical applications. We here present preliminary results preparing future pilot clinical studies with ex vivo cultured human hematopoietic cells.

Preclinical experience has shown that it is possible to maintain and expand hematopoietic cells in liquid culture systems by provision of optimal combinations of colony-stimulating factors (CSF). Ex vivo hematopoietic cell expansion (HCE) would be expected to reduce harvesting time and effort and could also decrease the infusion dose necessary for hematopoietic reconstitution after bone marrow transplantation. In addition, ex vivo expanded cells might be of value for therapeutic gene transfer. The central question in ex vivo HCE is whether the CSF combinations employed provide not only amplification of the late progenitor pools, but also maintenance or expansion of the stem cell compartment to ensure long term engraftment. Choice of CSF and experimental parameters in the culture system appear to be the most critical factors influencing the outcome of strategies for ex vivo HCE. Moreover, it is essential to define the goal of HCE and to adapt the experimental conditions to obtain the required cell populations. In future work, it remains to test the potential applicability of ex vivo expanded cells and to carefully monitor the possibility of the expansion of tumoral cells in ex vivo proliferation systems.

In the present paper, three multiparametric coagulation instruments were evaluated with regard to chronometric tests for aPTT (CK-Prest and automated APTT), PT (Recombiplastin and Thromborel), fibrinogen and factors of the prothrombin complex. Analysis of within-run precision and linearity and comparative studies showed the analytical performances of the instruments to differ according to the reagents used and emphasized the difficulty of finding the best compromise between instrument and reagent. On the basis of this study, the mechanical instrument appeared to be more versatile than the optical machines. This conclusion could however be modified after further evaluation of the recent new generation coagulation instruments.

The present study evaluated the clinical efficacity and tolerability of the subcutaneous (SC) administration of lenograstim, a glycosylated form of rHuG-CSF identical to human G-CSF, in the treatment of congenital agranulocytosis. Assessment criteria included neutrophil response and response stability, incidence and severity of infection and gingivostomatitis and quality of life. Lenograstim, at induction dosages of 5 (n = 9), 10 (n = 2) or 20 (n = 1) microgram/kg/day SC, produced neutrophil recovery in all of 12 children with congenital agranulocytosis. There was a median delay of 7 days to recovery after establishment of the effective induction dose. Whereas this dosage maintained a stable neutrophil response in 7 patients, the remaining 5 required dosage increases and dose reduction during maintenance therapy was not possible in these 5 cases. Among 4 patients stabilised at a dosage of 5 micrograms/kg/day, in 2 cases a lower minimum effective dose of 2 micrograms/kg/day was attained over the maintenance phase. Administration of twice the daily dose of lenograstim on alternate days was feasible in 3 of 8 patients. Lenograstim therapy reduced the incidence of infection and hospitalisation for infection relative to the prestudy period, while in 6 of 9 cases there was complete recovery from gingivostomatitis. Only one patient discontinued treatment on account of adverse events. Finally, perceived health and disease related symptoms showed a significant (p < 0.001) amelioration in the course of the study. Thus, lenogastrim produced sustained neurotrophil recovery in patients with congenital agranulocytosis, decreased the incidence and severity of infection and improved the quality of life.

G-CSF (5 mg/kg/day Filgrastim) was administered from day 7 after autologous bone marrow transplantation (ABMT) in a series of 17 patients treated for multiple myeloma or non-Hodgkin's lymphoma. In comparison with retrospective controls receiving ABMT without G-CSF and matched for age, underlying disease, disease status at ABMT, number of CFU-GM/kg reinfused, conditioning regimen and number and type of chemotherapy courses prior to ABMT, the duration of neutropenia, intravenous antibiotics and hospitalization was significantly reduced in the G-CSF group (p < 0.001). Delaying the administration of G-CSF after ABMT is an interesting possibility which merits further exploration in prospective randomized studies.