Genetic characterization of a unique neuroendocrine transdifferentiation prostate circulating tumor cell-derived eXplant model

Transformation of castration-resistant prostate cancer (CRPC) into an aggressive neuroendocrine disease (CRPC-NE) represents a major clinical challenge and experimental models are lacking. A CTC-derived eXplant (CDX) and a CDX-derived cell line are established using circulating tumor cells (CTCs) obtained by diagnostic leukapheresis from a CRPC patient resistant to enzalutamide. The CDX and the derived-cell line conserve 16% of primary tumor (PT) and 56% of CTC mutations, as well as 83% of PT copy-number aberrations including clonal TMPRSS2-ERG fusion and NKX3.1 loss. Both harbor an androgen receptor-null neuroendocrine phenotype, TP53, PTEN and RB1 loss. While PTEN and RB1 loss are acquired in CTCs, evolutionary analysis suggest that a PT subclone harboring TP53 loss is the driver of the metastatic event leading to the CDX. This CDX model provides insights on the sequential acquisition of key drivers of neuroendocrine transdifferentiation and offers a unique tool for effective drug screening in CRPC-NE management.

Abstract 5600: Establishment and characterization of a unique circulating tumor cells-derived xenograft (CDX) in prostate cancer

Background: The rarity of in vivo and in vitro human prostate cancer (PCa) models has hampered progress in understanding disease pathogenesis, metastatic progression and drug resistance mechanisms. Using CTCs from a leukapheresis product of a patient with advanced PCa, we report the establishment of a CDX and an in vitro cell line derived from this CDX. The phenotypic and molecular characterization of patient tumor-biopsies, CTCs, CDX and CDX-derived cell-line are presented.

Methods: Leukapheresis was performed in seven patients with advanced castration-resistant prostate cancer (CRPC). CTCs from the seven leukapheresis products were enriched by RosetteSep and implanted in Nod/Scid-IL2Rγ-/-mice. The CDX tumor was propagated in successive generations of mice. All samples, including eight tumor-biopsies performed at diagnosis two years prior leukapheresis and CTCs isolated at the single cell level during leukapheresis were characterized by immunofluorescence, immunohistochemistry, and whole-exome sequencing (WES).

Results: Based on CellSearch® counts in leukapheresis products, the estimated median number of engrafted CTCs was 697 (range: 10-19988). A mouse engrafted with 19988 CTCs developed a tumor within 193 days. Immunohistochemistry performed on the CDX and two tumor-biopsies indicated that the CDX and biopsies were positive for EpCAM, CK5/6/8/18, negative for CK7 and vimentin, and weakly positive for synaptophysin. While biopsies expressed PSA and the androgen receptor, the CDX was negative for both indicating tumor evolution. In contrast to tumor biopsies, the CDX strongly expressed Ki67, NSE and chromogranin, evidencing emergence of a neuroendocrine phenotype. The in vitro cell line established by culturing dissociated CDX cells for five months, grew in microspheres and expressed epithelial and ALDH and CD133 cancer stem-cell markers. By WES, a high degree of intra-tumor heterogeneity was observed in the eight tumor biopsies and CTCs as already reported in this tumor type. Only 2.8% (58/2087) and 2.3% (49/2087) of the mutations present in the tumor biopsies were identified in CTCs and the CDX respectively, indicating that a very few number of mutations have the potential to support the dissemination and tumorigenic activity of CTC. Trunk mutations in TP53, NF1 and LRP1B genes were identified in all samples including the CDX while PTEN gene loss was acquired lately and detected only in CTCs and the CDX. Mutational similarity of the CDX and the in vitro cell line was 91%. The analysis of copy number variations is ongoing in all samples and will be presented.

Conclusion: We report the first PCa CDX model, demonstrating the tumorigenicity of CTCs from CRPC. This CDX model represents a unique tool to identify clonal mutations associated with the tumor-initiating capacity of CTCs and explore the genetic and phenotypic basis of metastasis and drug resistance in advanced CRPC.

Citation Format: Vincent Faugeroux, Emma Pailler, Olivier Deas, Virginie Marty, Kamélia Alexandrova, Kiki Andree, Jean-Yves Scoazec, Nikolas Stoecklein, Nicolo Manaresi, Dominique Tramalloni, Maud Ngo-Camus, Claudio Nicotra, Leon Terstappen, Valérie Lapierre, Karim Fizazi, Yohann Loriot, Jean-Gabriel Judde, Françoise Farace. Establishment and characterization of a unique circulating tumor cells-derived xenograft (CDX) in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5600.

MUB40 Binds to Lactoferrin and Stands as a Specific Neutrophil Marker

Neutrophils represent the most abundant immune cells recruited to inflamed tissues. A lack of dedicated tools has hampered their detection and study. We show that a synthesized peptide, MUB₄₀, binds to lactoferrin, the most abundant protein stored in neutrophil-specific and tertiary granules. Lactoferrin is specifically produced by neutrophils among other leukocytes, making MUB₄₀ a specific neutrophil marker. Naive mammalian neutrophils (human, guinea pig, mouse, rabbit) were labeled by fluorescent MUB₄₀ conjugates (-Cy5, Dylight405). A peptidase-resistant retro-inverso MUB₄₀ (RI-MUB₄₀) was synthesized and its lactoferrin-binding property validated. Neutrophil lactoferrin secretion during in vitro Shigella infection was assessed with RI-MUB₄₀-Cy5 using live cell microscopy. Systemically administered RI-MUB₄₀-Cy5 accumulated at sites of inflammation in a mouse arthritis inflammation model in vivo and showed usefulness as a potential tool for inflammation detection using non-invasive imaging. Improving neutrophil detection with the universal and specific MUB₄₀ marker will aid the study of broad ranges of inflammatory diseases.

Critical role of the HDAC6-cortactin axis in human megakaryocyte maturation leading to a proplatelet-formation defect

Thrombocytopenia is a major side effect of a new class of anticancer agents that target histone deacetylase (HDAC). Their mechanism is poorly understood. Here, we show that HDAC6 inhibition and genetic knockdown lead to a strong decrease in human proplatelet formation (PPF). Unexpectedly, HDAC6 inhibition-induced tubulin hyperacetylation has no effect on PPF. The PPF decrease induced by HDAC6 inhibition is related to cortactin (CTTN) hyperacetylation associated with actin disorganization inducing important changes in the distribution of megakaryocyte (MK) organelles. CTTN silencing in human MKs phenocopies HDAC6 inactivation and knockdown leads to a strong PPF defect. This is rescued by forced expression of a deacetylated CTTN mimetic. Unexpectedly, unlike human-derived MKs, HDAC6 and CTTN are shown to be dispensable for mouse PPF in vitro and platelet production in vivo. Our results highlight an unexpected function of HDAC6–CTTN axis as a positive regulator of human but not mouse MK maturation.

Histone deacetylase (HDAC) inhibitors, a class of cancer therapeutics, cause thrombocytopenia via an unknown mechanism. Here, the authors show that HDAC6 inhibition impairs proplatelet formation in human megakaryocytes, and show that this is linked to hyperacetylation of the actin-binding protein cortactin.

Abstract 1723: Diagnostic leukapheresis results in a significant increase in CTC yield in metastatic breast and prostate cancer

Introduction Frequently the number of CTC isolated in 7.5 mL of blood is too small to reliably determine tumor heterogeneity and to be representative as a ‘liquid biopsy’. In the EU FP7 program CTCTrap we aimed to validate and optimize the recently introduced Diagnostic LeukApheresis (DLA; doi: 10.1073/pnas.1313594110) approach to screen liters of blood and thereby substantially increasing the number of CTC available for further characterization. Here we present the results obtained from 32 metastatic cancer patients subjected to DLA in the participating institutions.

Methods Before the DLA procedure, whole blood was drawn in a CellSave blood collection tube and a 7.5 ml aliquot was processed with the ‘gold standard’ reference CellSearch® (Janssen Diagnostics, USA). DLAs from metastatic cancer patients were performed for ≈90 minutes to obtain 40 mL of product containing ≈4x109 mononuclear cells (MNC) representing ≈1 liter of blood. The obtained DLA samples were then divided, fixed with CellSave preservative, prepared and processed with each of the analysis techniques as described in the Standard Operating Procedures developed for DLA in the CTCTrap consortium (https://www.utwente.nl/tnw/mcbp/protocolsandtools/).

Results DLAs were obtained from 20 metastatic prostate cancer patients and 12 metastatic breast cancer patients at four different European academic medical institutions. Using a SOP for the DLA procedure, similar DLA products (MNC concentration: 64x106/mL, SD = 38x106) could be generated without any noticeable side effects. CTC in 7.5 mL of blood ranged from 0 to 324 (mean = 61, median = 18). DLA processed with CellSearch represented 7 to 212 mL of blood (mean = 100, median = 97), CTC ranged from 0 to 2913 (mean = 330, median = 105). Resulting in a significant increase in CTC yield (p = 0.004) ranging from 0x to 40x (mean = 13, median = 9) when comparing 1mL of whole blood to 1mL of DLA. Filtration of 50x106 WBC of DLA, through 5um microsieves yielded only 0 to 12 CTC (mean = 2, median = 0, n = 16). Leukocyte depletion of 18 mL of DLA followed by filtration yielded 0 to 178 CTC (mean = 37, median = 4, n = 22) not yielding a relative increase versus CellSearch DLA. Leukocyte depletion followed by CellSearch yielded 271 to 1620 CTC (mean = 792, median = 484, n = 3) also not yielding a relative increase versus CellSearch DLA. In 7 patients 0 CTC were detected in 7.5mL of blood, in 4 out of these 7 patients CTC were detected in DLA.

Conclusion The yield of CTC can be significantly increased by the use of DLA in patients with CTC detected in 7.5 mL of blood. Technology to select CTC from DLAs will need to be further improved before one can make optimal use of the large processed blood volumes.

Citation Format: Kiki C. Andree, Anouk Mentink, Joost F. Swennenhuis, Leon W. Terstappen, Nikolas H. Stoecklein, Rui P. Neves, Rita Lampignano, Hans Neubauer, Tanja Fehm, Johannes C. Fischer, Elisabetta Rossi, Mariangela Manicone, Umberto Basso, Piero Marson, Rita Zamarchi, Yohann Loriot, Valérie Lapierre, Vincent Faugeroux, Marianne Oulhen, Francoise Farace, Gemma Fowler, Mariane Sousa Fontes, Berni Ebbs, Maryou Lambros, Mateus Crespo, Penelope Flohr, Johann S. de Bono. Diagnostic leukapheresis results in a significant increase in CTC yield in metastatic breast and prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1723. doi:10.1158/1538-7445.AM2017-1723

The cell division control protein 42-Src family kinase-neural Wiskott-Aldrich syndrome protein pathway regulates human proplatelet formation

Essentials The role of the cytoskeleton during megakaryocyte differentiation was examined. Human megakaryocytes are derived from in vitro cultured CD34+ cells. Cell division control protein 42 (CDC42) positively regulates proplatelet formation (PPF). Neural Wiskott-Aldrich syndrome protein, the main effector of CDC42 with Src positively regulates PPF.

SUMMARY

Background Cytoskeletal rearrangements are essential for platelet release. The RHO small GTPase family, as regulators of the actin cytoskeleton, play an important role in proplatelet formation (PPF). In the neuronal system, CDC42 is involved in axon formation, a process that combines elongation and branching as for PPF. Objective To analyze the role of CDC42 and its effectors of the Wiskott-Aldrich syndrome protein (WASP) family in PPF. Methods Human megakaryocytes (MKs) were obtained from CD34+ cells. Inhibition of CDC42 in MKs was performed with the chemical inhibitor CASIN or with an active or a dominant-negative form of CDC42. The knock-down of N-WASP was obtained with a small hairpin RNA strategy Results Herein, we show that CDC42 activity increased during MK differentiation. The use of the chemical inhibitor CASIN or of an active or a dominant-negative form of CDC42 demonstrated that CDC42 positively regulated PPF in vitro. We determined that N-WASP, but not WASP, regulated PPF. We found that N-WASP knockdown led to a marked decrease in PPF, owing to a defect in the demarcation membrane system (DMS). This was associated with RHOA activation, and a concomitant augmentation in the phosphorylation of mysosin light chain 2. Phosphorylation of N-WASP, creating a primed form of N-WASP, increased during MK differentiation. Phosphorylation inhibition by two Src family kinase inhibitors decreased PPF. Conclusions We conclude that N-WASP positively regulates DMS development and PPF, and that the Src family kinases in association with CDC42 regulate PPF through N-WASP.

Uncoupling of the Hippo and Rho pathways allows megakaryocytes to escape the tetraploid checkpoint

Megakaryocytes are naturally polyploid cells that increase their ploidy by endomitosis. However, very little is known regarding the mechanism by which they escape the tetraploid checkpoint to become polyploid. Recently, it has been shown that the tetraploid checkpoint was regulated by the Hippo-p53 pathway in response to a downregulation of Rho activity. We therefore analyzed the role of Hippo-p53 pathway in the regulation of human megakaryocyte polyploidy. Our results revealed that Hippo-p53 signaling pathway proteins are present and are functional in megakaryocytes. Although this pathway responds to the genotoxic stress agent etoposide, it is not activated in tetraploid or polyploid megakaryocytes. Furthermore, Hippo pathway was observed to be uncoupled from Rho activity. Additionally, polyploid megakaryocytes showed increased expression of YAP target genes when compared to diploid and tetraploid megakaryocytes. Although p53 knockdown increased both modal ploidy and proplatelet formation in megakaryocytes, YAP knockdown caused no significant change in ploidy while moderately affecting proplatelet formation. Interestingly, YAP knockdown reduced the mitochondrial mass in polyploid megakaryocytes and decreased expression of PGC1α, an important mitochondrial biogenesis regulator. Thus, the Hippo pathway is functional in megakaryocytes, but is not induced by tetraploidy. Additionally, YAP regulates the mitochondrial mass in polyploid megakaryocytes.

Clinical impact of the NKp30/B7-H6 axis in high-risk neuroblastoma patients

The immunosurveillance mechanisms governing high-risk neuroblastoma (HR-NB), a major pediatric malignancy, have been elusive. We identify a potential role for natural killer (NK) cells, in particular the interaction between the NK receptor NKp30 and its ligand, B7-H6, in the metastatic progression and survival of HR-NB after myeloablative multimodal chemotherapy and stem cell transplantation. NB cells expressing the NKp30 ligand B7-H6 stimulated NK cells in an NKp30-dependent manner. Serum concentration of soluble B7-H6 correlated with the down-regulation of NKp30, bone marrow metastases, and chemoresistance, and soluble B7-H6 contained in the serum of HR-NB patients inhibited NK cell functions in vitro. The expression of distinct NKp30 isoforms affecting the polarization of NK cell functions correlated with 10-year event-free survival in three independent cohorts of HR-NB in remission from metastases after induction chemotherapy (n = 196, P < 0.001), adding prognostic value to known risk factors such as N-Myc amplification and age >18 months. We conclude that the interaction between NKp30 and B7-H6 may contribute to the fate of NB patients and that both the expression of NKp30 isoforms on circulating NK cells and the concentration of soluble B7-H6 in the serum may be clinically useful as biomarkers for risk stratification.

Dendritic cell-derived exosomes as maintenance immunotherapy after first line chemotherapy in NSCLC

Dendritic cell-derived exosomes (Dex) are small extracellular vesicles secreted by viable dendritic cells. In the two phase-I trials that we conducted using the first generation of Dex (IFN-γ-free) in end-stage cancer, we reported that Dex exerted natural killer (NK) cell effector functions in patients. A second generation of Dex (IFN-γ-Dex) was manufactured with the aim of boosting NK and T cell immune responses. We carried out a phase II clinical trial testing the clinical benefit of IFN-γ-Dex loaded with MHC class I- and class II-restricted cancer antigens as maintenance immunotherapy after induction chemotherapy in patients bearing inoperable non-small cell lung cancer (NSCLC) without tumor progression. The primary endpoint was to observe at least 50% of patients with progression-free survival (PFS) at 4 mo after chemotherapy cessation. Twenty-two patients received IFN-γ-Dex. One patient exhibited a grade three hepatotoxicity. The median time to progression was 2.2 mo and median overall survival (OS) was 15 mo. Seven patients (32%) experienced stabilization of >4 mo. The primary endpoint was not reached. An increase in NKp30-dependent NK cell functions were evidenced in a fraction of these NSCLC patients presenting with defective NKp30 expression. Importantly, MHC class II expression levels of the final IFN-γ-Dex product correlated with expression levels of the NKp30 ligand BAG6 on Dex, and with NKp30-dependent NK functions, the latter being associated with longer progression-free survival. This phase II trial confirmed the capacity of Dex to boost the NK cell arm of antitumor immunity in patients with advanced NSCLC.

Ancestim (r-metHuSCF) plus filgrastim and/or chemotherapy for mobilization of blood progenitors in 513 poorly mobilizing cancer patients: the French compassionate experience

Ancestim (r-MetHuSCF) is available in France for compassionate use in patients who are candidates for high-dose chemotherapy and autologous transplantation, and who failed in previous attempts at mobilization and collection. We report here data from 513 adult patients who benefited from this program, between January 1998 and July 2007. Given with systematic premedication, ancestim was generally well tolerated, although severe but not life-threatening adverse events were reported in 12 individuals. Overall, a graft was obtained or completed for 235 patients (46%). The median number of collected CD34+ cells was 3.00 × 10(6)/kg (range: 0.03-39.50). The target threshold of 2 × 10(6) CD34+ cells/kg was reached in 161 patients (31%). Factors associated with collection were diagnosis of myeloma, no previous autologous transplant, no more than one previous failed attempt and a mobilization regimen including cytotoxic agents. A total of 207 patients (40%) proceeded to high-dose chemotherapy and autologous transplantation. The median time to reach 0.5 × 10(9)/L neutrophils and 20 × 10(9)/L platelets was 12 (6-40) and 13 (0-31) days, respectively. We conclude that a combination of ancestim with filgrastim successfully mobilized CD34+ cells in peripheral blood, and allowed adequate collection in preparation for autologous transplantation in approximately one-third of poorly mobilizing patients.

[Quality control of defrosted cord blood units: results from an inter-laboratory study]

PURPOSE

Today, haematopoietic stem cell graft from placental blood concerns more than 15 % of allogeneic grafts. An inter-laboratory study of the quality control of defrosted cord blood units has been coordinated by the French society for cell and tissue bioengineering (SFBCT), with the cord blood bank of Bourgogne Franche-Comté and controlled by the French health products safety agency (Afssaps). The aim of this study is to ensure the inter-laboratory reproducibility of the quality controls practised by the banks during defrosting. The cellular outputs were analyzed according to the defrosting techniques, according to the method used in flow cytometry: single-platform (SP) versus double-platform (DP), or the product nature, i.e. in total blood or miniaturized.

METHODS

Forty-two units of placental blood (USP), which were out of range were provided for defrosting to 14 participating sites. USP were defrosted and controlled according to the procedures of each bank. Once the USP is defrosted, a part of the product was controlled by the site and the other part by Afssaps. Following controls were carried out: numeration of the total nucleated cells (TNC) and of CD34+ cells (made by a SP method in Afssaps) and functional assay.

RESULTS

Concerning TNC, the defrosting sites obtained a cellular output of 94 %+/-28 in day 0 compared with an output of 72 %+/-24 in Afssaps showing a rather good stability of the USP transmitted with an average deviation of 23 %+/-22. The freezing process with or without reduction of volume does not affect this variation. Concerning the numeration of CD34+ cells, the average deviation between the participating sites and Afssaps was 29 %+/-23 compared with 21 %+/-16 for the sites using a SP method against 47 %+/-25 for those using a DP method. The CD34+ outputs are equal to 82 % +/- 60 in day 0 for the participating sites against 52 %+/-20 for Afssaps. For the sites using a DP method, it is stressed that this output is particularly high with a rate of 126 %+/-90 (n=15) whereas it is 62 %+/-20 (n=32) for the sites using a SP method.

CONCLUSION

These results underline a good stability of viable CD34+ cells and a greater reliability of the SP methods for the CD34+ cell numeration for these defrosted USP. Lastly, the results of the functional assay regarding the average clonogenicities (equal to 15 %) reinforce the conclusions on the quality of the defrosted products.

Results of cryopreserved parathyroid autografts: a retrospective multicenter study

BACKGROUND

The functionality of cryopreserved parathyroid autotransplantation (CPAT) has been evaluated in few studies, mostly conducted by experienced single-institution centers that have reported different success rates ranging from 17% to 83%. In France, CPAT are rare and their functionality has never been evaluated. Moreover, French tissue banks are facing an accumulation of ungrafted samples. The aim of our work was to evaluate the implantation rate of cryopreserved parathyroid samples and the functionality of CPAT in a multicenter study.

METHODS

Data from 9 French tissue banks were analyzed. CPAT functionality was defined as fully functional (normal parathyroid hormone [PTH] and calcium levels without treatment), partially functional (normal PTH levels but need for treatment to maintain normocalcemia), and nonfunctional (low PTH levels and need for treatment). For dialyzed patients, CPAT was considered nonfunctional if the PTH level in the nongrafted arm was less than 20 pg/mL, partially functional if the PTH level was between 20 and 50 pg/mL, and fully functional if the PTH level was between 50 and 300 pg/mL.

RESULTS

The 9 centers had cryopreserved 1376 samples of parathyroid tissue and only 22 (1.6%) had been autografted in 20 patients (65% renal hyperparathyroidism, 20% multiple endocrine neoplasia type 1, 15% "other") by 12 different surgical teams. The median duration of storage was 11.1 months (range, 0.4-28.5). Only 2 autografts (10%) were fully functional, 2 (10%) were partially functional, and 17 (80%) were nonfunctional at 26 months median follow-up.

CONCLUSION

The reimplantation rate is low, and the functionality of CPAT is less than those published by experienced centers. Logistical and technical problems occurring in less experienced centers are probably the main reasons for nonfunctioning implants. Considering the results of this study, we suggest that cryopreservation of parathyroid glands should be abandoned when not performed in very large experimented centers, that CPAT should be used only for patients with hyperplasic parathyroid tissue, and that tissue samples should be systematically destroyed when patients do not have hypoparathyroidism or after 1 year of storage.

Dendritic cell-derived exosomes for cancer immunotherapy: what's next?

Exosomes are nanovesicles originating from late endosomal compartments and secreted by most living cells in ex vivo cell culture conditions. The interest in exosomes was rekindled when B-cell and dendritic cell-derived exosomes were shown to mediate MHC-dependent immune responses. Despite limited understanding of exosome biogenesis and physiological relevance, accumulating evidence points to their bioactivity culminating in clinical applications in cancer. This review focuses on the preclinical studies exploiting the immunogenicity of dendritic cell-derived exosomes (Dex) and will elaborate on the past and future vaccination trials conducted using Dex strategy in melanoma and non-small cell lung cancer patients.

Immune modulation and microchimerism after unmodified versus leukoreduced allogeneic red blood cell transfusion in cancer patients: results of a randomized study

BACKGROUND

Transfusion of red blood cells (RBCs) has been associated with immunomodulatory effects. Persistence of donor cells in the recipient may be contributive.

STUDY DESIGN AND METHODS

A randomized single-center trial was conducted to compare microchimerism and immune responses in 35 patients undergoing cancer surgery and transfused perioperatively with either unmodified RBCs (UN-RBCs, n = 18) or leukoreduced RBCs (LR-RBCs, n = 17). Biologic parameters included microchimerism assessment peripheral blood mononuclear cell (PBMNC) phenotyping, cytokine production by stimulated PBMNCs, FoxP3 gene expression, and T-cell repertoire (TCR) analysis.

RESULTS

Microchimerism was documented in 8 of 18 patients after UN-RBC transfusion while absent after LR-RBC transfusion (0/17; p = 0.001). After UN-RBC transfusion, microchimerism was associated with increased interleukin (IL)-10 production (p = 0.02), reduced TCR alteration (p = 0.04), and reduced CD56+ cell counts (p = 0.02) when compared to recipients without evidence for microchimerism. FoxP3 gene expression did not differ significantly between both treatment groups nor with the presence or absence of microchimerism in the UN-RBC group. Finally, after an initial early decrease after surgery and transfusion, IL-12 production increased and more significantly so after UN-RBC transfusion versus LR-RBC transfusion (p = 0.05).

CONCLUSION

UN-RBC-induced microchimerism is associated with specific immunomodulatory effects in cancer patients who received transfusions during surgery.

Occurrence and severity of adverse events after autologous hematopoietic progenitor cell infusion are related to the amount of granulocytes in the apheresis product

BACKGROUND

Adverse events (AEs) after hematopoietic progenitor cell (HPC) infusion are rare but might be life-threatening. These reactions have traditionally been associated with the amount of infused cryoprotectant, but persistence of such events after dimethyl sulfoxide (DMSO) depletion has questioned this assumption.

STUDY DESIGN AND METHODS

The incidence of AEs on a cohort of 460 patients (490 HPC infusions) undergoing autologous DMSO-reduced HPC transplantation was prospectively evaluated. HPCs were collected from adult patients with various hematologic or solid malignancies. After quality control (QC) on fresh apheresis products and subsequent cryopreservation, HPC grafts were thawed and washed at the cell therapy facility. QC was performed on each graft after washing, and clinical data were collected for each infusion.

RESULTS

AEs were reported in 66 cases (13.5%) and were graded according to the NCI-CTC scale from 1 to 4. Although none of the factors associated with patient characteristics or infusion procedure were different between the two groups (no AE vs. occurrence of AE), it was found that the absolute number of granulocytes measured before freezing was considerably higher in the AE group. Furthermore, within this group, there was a strong correlation between the amount of granulocytes and the grading of the reaction.

CONCLUSION

This survey demonstrates that AEs occurring in the setting of DMSO-reduced HPC grafts are directly related to the amount of granulocytes and thus emphasizes the need for high-quality apheresis products so as to improve the safety of HPC infusion.

CD34+ progenitors are reproducibly recovered in thawed umbilical grafts, and positively influence haematopoietic reconstitution after transplantation

Cord blood (CB) units are increasingly used for allogeneic transplantation. Cell dose, a major factor for CB selection, is evaluated before freezing by each CB bank, using various techniques. This may introduce variability and affect the prediction of cell recovery after thawing, or haematopoietic reconstitution. Forty-two children were transplanted at the same institution with unrelated CB units. All units were thawed and evaluated at the same cell therapy facility, using standard procedures. We investigated: (i) factors that affect cell loss after thawing, and (ii) the importance of CD34(+) cell doses. Prefreeze and post-thaw CD34(+) cell doses were statistically correlated, thus suggesting that variability in numeration techniques used by different CB banks does not compromise the biological and clinical value of these figures. CD34(+) cell recovery appeared to be correlated with the absolute number of CD34(+) cells per frozen bag. Infused CD34(+) is the cell dose that better correlates with platelet reconstitution delay; in addition, when using a quartile comparison, haematopoietic recovery appeared to be related with prefreeze and post-thaw CD34(+) cell doses. We conclude that enumeration of CD34(+) cells in CB units is of biological significance, and may help select CB units and identify patients at risk of delayed recovery.

Cord blood volume reduction using an automated system (Sepax) vs. a semi-automated system (Optipress II) and a manual method (hydroxyethyl starch sedimentation) for routine cord blood banking: a comparative study

Background With the development of cord blood banking, solutions have to be found to solve the storage space problem, by reducing the volume of cord blood units (CBU). Methods We compared total nucleated cell (TNC) and CD34(+) cell counts before and after processing with three different CBU volume reduction methods used consecutively in our bank: a manual method based on hydroxyethyl starch sedimentation (HES) (n=447), a top-and-bottom (TB) semi-automated method (n=181) using Optipress II, and the Sepax automated method (n=213). Statistical analysis was done using t-tests, linear regression and Spearman correlation coefficients. Adjusted variables included TNC, CD34(+) cell counts, CD34(+) cell percentage and CB volume before processing. Results TNC recovery was higher with Sepax (80.3+/-7.7%) than with HES (76.8+/-9.1%) and TB (60.7+/-13.5%) (P<0.0001, both). It was higher with HES than with TB (P<0.0001). CD34(+) cell recovery was higher with Sepax (86+/-11.6%) than with HES (81.5+/-12.5%) and TB (82.0+/-17.7%) (P<0.008 and <0.0001, respectively) and results with HES and TB were not significantly different (P=0.7). Interestingly, with Sepax, TNC and CD34(+) cell recoveries were not correlated with pre-processing values (P=0.8 and 0.4, respectively). Discussion In conclusion, the Sepax volume reduction method allows higher TNC and CD34(+) cell recoveries.

Implication du personnel infirmier dans la sécurité transfusionnelle : évaluation des connaissances et de la pratique à l'institut Gustave-Roussy

BACKGROUND

A first survey on nurses transfusion practices at our Hospital revealed poor knowledge. Good Transfusion Practices were written, a training program was implemented and a second survey was carried out two years later. STUDY DESIGN AN METHODS: We conducted the second survey in which 4 of the questions were identical to those in the first survey in order to assess the impact of this training strategy. The 4 questions were on blood sample identification, checking patient identification, checking "use by date" on blood product bag and the pre-transfusion bedside compatibility test. Behaviours were evaluated by checking the pre-transfusion procedures, including interpretation of bedside compatibility tests. We investigated the impact of attendance at the training course, the period of employment, day versus night shift and attempted to correlate these factors with the results of the second survey.

RESULTS

A significant improvement was observed in knowledge of Good Practices between the first and the second survey (P = 10(-4)). However, the multivariate analysis showed that the impact of training was heterogeneous. Pre-transfusion protocol checks have improved significantly (P = 0.05) as well as pre-transfusion bedside compatibility test interpretation of ABO compatibility (P = 0.007).

CONCLUSION

In our study, the implementation of Good practices has significantly improved nurses' knowledge about transfusion safety requirements but it is essential to continue and adapt the training and cheek regularly the impact of these implementations.

Platelet transfusion containing ABO-incompatible plasma and hepatic veno-occlusive disease after hematopoietic transplantation in young children

BACKGROUND

Hepatic veno-occlusive disease is a major limiting factor of high-dose chemotherapy in children. The cells lining the hepatic vascular endothelium express blood group A and/or B antigens according to the patient's blood group. We designed a study evaluating the impact of platelet concentrates containing ABO-incompatible plasma transfused to young children with a high risk of hepatic veno-occlusive disease.

METHODS

In all, 186 consecutive children (median age: 4 years, range: 0.75-17 years), treated with high-dose chemotherapy containing busulfan followed by hematopoietic stem cell transplantation for neuroblastoma (n=112) or brain tumor (n=74) between 1988 and 1998, were investigated. The main endpoint was the occurrence of hepatic veno-occlusive disease. Multivariate analysis was performed using a Cox's regression model with transfusion of platelet concentrates containing ABO-incompatible plasma as a time-dependent covariate.

RESULTS

We found that 73 out of 186 (39%) children developed hepatic veno-occlusive disease after transplantation. Multivariate analysis demonstrated that two factors significantly increased the risk of hepatic veno-occlusive disease occurrence: transfusion of platelet concentrates containing ABO-incompatible plasma (P=0.003) and use of melphalan in the conditioning regimen (P=0.006). Conversely, the number of platelet concentrates transfusions per week, child's age, weight, sex, and use of cyclophosphamide in the conditioning regimen had no effect.

CONCLUSIONS

Transfusion of platelet concentrates containing ABO-incompatible plasma increases the risk of hepatic veno-occlusive disease in young children treated with a busulfan-containing regimen. Binding of A and/or B antigens expressed on the surface of hepatic endothelial cells may promote this complication. Transfusion of platelet concentrates containing ABO-incompatible plasma should be avoided in these children.

Reliability and validity of the Functional Assessment of Cancer Therapy General (FACT-G) in French cancer patients

This report describes the reliability and validity of a French version of the Functional Assessment of Cancer Therapy - General (FACT-G) with a French sample of 493 cancer patients. The FACT-G consists of 27 items and four subscales: Physical (PWB), Functional (FWB), Social/Family (SFWB) and Emotional well-being (EWB). The study sample includes 64% with localized disease, 26% with metastases, 11% in remission, and 71% receiving radiation/chemotherapy. Internal consistency Cronbach alphas of the global FACT-G scale (0.90) and subscales (>0.75) are satisfactory (n = 126). Test-retest reproducibility is satisfactory for all subscales and the global scale (n = 87 to 93, r = 0.74 to 0.90). ANOVA models show that PWB differentiated between the three disease stages; the global FACT-G and FWB discriminated between patients with metastases and others with localized disease or in remission; EWB only discriminated between metastases and localized disease; while SFWB did not discriminate between groups at different stages of cancer. Only the PWB subscale discriminated between patients with no history from those receiving chemotherapy (p < or = 0.05). None of the scales discriminated between groups based on radiotherapy. These results may be useful in the design and interpretation of clinical trials involving French patients when the FACT-G is the outcome measure.

Traitement des syndromes secs graves par sérum autologue

BACKGROUND

Dry eye syndrome with tear deficiency can be improved with artificial tears, which can be associated with topical anti-inflammatory agents. Autologous serum can provide the ocular surface with beneficial growth factors and vitamins.

PATIENTS AND METHODS

Twenty-one patients suffering from severe dry eye due to Sjögren's syndrome were treated with 20% autologous serum for 2 Months. The Schirmer I test, break-up time, and fluorescein and lissamine green stainings were performed before and after treatment. Subjective complaints such as burning, foreign body sensation, dryness and photophobia were assessed by a questionnaire as well as a face score reflecting the current condition of patients' eyes.

RESULTS

Lissamine green and fluorescein scores improved significantly as well as subjective symptoms of burning, foreign body sensation and dryness (p<0.05). The face score was significantly improved. Bacterial culture of serum delivered to the patients all remained negative.

DISCUSSION

Autologous serum provides growth factors and vitamins that are useful for an altered ocular surface due to Sjögren's disease. However, some problems still remain: risk of contamination, arbitrary dilution of autologous serum, and a current lack of regulations for use of autologous serum. A close collaboration between ophthalmologists and the Etablissement Français du Sang (French Blood Bank) is mandatory because autologous serum should be considered as a useful tool to treat severe ocular surface disorders.

CONCLUSION

The use of autologous serum improved symptoms and objective signs caused by severe Sjögren's syndrome. Currently, a lack of clear regulations prevents its widespread use in severe ocular surface disorders.

Blood versus marrow hematopoietic allogeneic graft

Allogeneic G-CSF-mobilized blood cell transplantation (BCT), an alternative to allogeneic bone marrow transplantation (BMT), is associated with enhanced engraftment and accelerated hematopoietic recovery. In addition, immune reconstitution and overall alloreactivity after BCT versus BMT differ significantly. Indeed, despite an increased number of donor T cells infused, the incidence of acute graft-versus-host disease (GvHD) after BCT appears to remain identical or lesser than after BMT. On the other hand, a higher risk of chronic GvHD has been reported after BCT. In a SFGM phase III trial, 101 patients with early leukemia and an HLA-matched sibling donor randomly received a BCT or BMT. BCT was associated with a higher number of infused CD34+ cells, accelerated platelet and neutrophil reconstitution, fewer platelet transfusions and similar acute GvHD incidence. However, chronic GvHD occurred more frequently after BCT. With a median follow-up of 20 months, relapse, survival and leukemia-free survival were not different. In the course of this study, immune parameters related to the graft as well as to early reconstitution were prospectively examined. T cells subsets, B cells, NK cells and monocytes numbers were significantly higher in BC grafts (versus BM). T cells in BC grafts were less activated than in BM grafts. Frequency of IFN-gamma, IL-2- and TNF-alpha-secreting cells and single-cell IFN-gamma production potential was reduced in BC graft. One month after BCT, blood T-cell counts were 3-fold higher than after BMT. Moreover, post-BCT T cells were less activated and counts correlated with the number of T cells infused with the graft, which was not the case after BMT. Several acute hemolysis episodes, resulting from anti-A and/or -B donor-derived Ab directed at Ag present on recipient red blood cells (minor ABO mismatch), have been described after BCT. Recipients indeed exhibited significantly increased anti-A and/or -B Ab titers after BCT, particularly in the setting of a "minor" ABO mismatch. Furthermore, the frequency of anti-HLA Ab early after BCT was significantly increased (despite the reduction in platelet transfusion requirements). The higher number of activated B cells and/or CD4 T cells and monocytes in a BCT graft and/or the higher number of circulating CD4 T- and B-cells after BCT could be associated with the enhanced alloAb production. G-CSF-induced TH2 cytokine profile of the T cells present in the graft could also be contributive. Recent studies have determined that BC grafts contained a higher number of type 2 dendritic cells (DC2), themselves associated with high frequencies of TH2 CD4+ cells. Since chronic GvHD is associated with the occurrence of Ab-mediated auto-immune-like syndromes, it is tempting to speculate that a higher incidence of chronic GvHD may result from these findings. In conclusion, BCT results in clinically relevant distinct hematopoietic and immune reconstitution patterns.

Bacterial contamination of a cornea tissue bank: implications for the safety of graft engineering

PURPOSE

To analyze the difficulties involved in managing an episode of bacterial contamination in a cornea bank. We describe (1) the circumstances of bacterial contamination discovery, (2) the methods used to investigate the outbreak, (3) the corrective measures adopted, and (4) the method introduced to improve the reaction capacity in case of bacterial contamination.

METHODS

All the samples collected were cultured in an attempt to identify the environmental reservoir of the contaminated epidemic clone. Bacteria were identified by Gram stain, oxidase test, and biochemical characteristics. The clonality of the strains was assessed by pulsed-field gel electrophoresis.

RESULTS

The bacterial contamination was confirmed for 28 corneas, and 70 additional corneas were discarded. The source of the contamination was identified 17 days after the beginning of the episode. It consisted of a clonal bacterial strain that was found in trypan blue, the dye, used to examine all the tissues. The contaminating bacterium was Burkholderia cepacia, a well-known nosocomial pathogen. A total of 169 grafted corneas had been checked with the contaminated reagent. No cases of post-graft infection were recorded.

CONCLUSION

Trypan blue played a major role in this outbreak. The mode and chronology of contamination remain unresolved. This exceptional event emphasizes the risk of bacterial contamination in tissue/cell banks, the necessity to improve methods for its prevention, and procedures to limit its consequences.

Increased presence of anti-HLA antibodies early after allogeneic granulocyte colony-stimulating factor-mobilized peripheral blood hematopoietic stem cell transplantation compared with bone marrow transplantation

We have recently shown that the use of allogeneic granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood hematopoietic stem cell transplantation (PBHSCT), as compared with bone marrow transplantation (BMT), is associated with increased titers of antibodies (Abs) directed against red blood cell ABO antigens. To further evaluate the influence of a G-CSF-mobilized PBHSCT graft on alloimmune Ab responses, we examined the frequency of anti-HLA Abs after transplantation in the setting of the same randomized study, comparing PBHSCT with BMT in adults. Anti-HLA Ab presence was determined by complement-dependent cytotoxicity assay (CDC) and flow cytometry in the recipient before and 30 days after transplantation as well as in the donor before graft donation. The use of PBHSCT was significantly associated with increased detection of anti-HLA immunoglobulin G (IgG) Abs early after transplantation as evidenced by flow cytometry (11 of 24 versus 4 of 27 transplant recipients, P =.03) and, less so, by CDC (5 of 24 versus 1 of 27 transplant recipients, P =.09). The difference between PBHSCT and BMT was further heightened when analysis was restricted to anti-HLA IgG Ab-negative donor/recipient pairs. In such a setting, early anti-HLA Ab was never detected after BMT but was repeatedly detected after PBHSCT (flow cytometry, 6 of 18 versus 0 of 17 transplant recipients, P =.02; CDC, 4 of 23 versus 0 of 26 transplant recipients, P =.04). Importantly, the PBHSCT-associated increase in anti-HLA Ab detection was observed despite a reduction in the median number of platelet-transfusion episodes per patient in PBHSC transplant versus BM transplant recipients (3 platelet-transfusion episodes [range, 1-21] in PBHSCT group vs 6 platelet-transfusion episodes [range, 3-33] in the BMT group; P =.02). In conclusion, this study strongly suggests that G-CSF-mobilized PBHSCT results in an increased incidence of circulating anti-HLA Abs and further confirms that the use of such a graft alters alloimmune Ab responses.

Buprenorphine prescription by general practitioners in a French region

Since 1996 French general practitioners (GPs) may prescribe sublingual buprenorphine tablets as maintenance treatment for opiate dependence. The computerised data management of the main French health reimbursement system now allows surveillance of the use of this drug, and how it is prescribed. The purpose of this study is to determine the profile of maintained patients, prescribed doses, associated psychotropic treatments and how practitioners prescribe these treatments. This study analyses the 11186 buprenorphine prescriptions electronically transmitted for reimbursement between September and December 1999 in a specific French region. It was found that the 2078 treated patients consumed a mean of 11.5 mg of buprenorphine per day and 12% of them procured prescriptions from more than two prescribers. 43% of maintained patients had an associated benzodiazepine prescription, mainly flunitrazepam, often on the same prescription form. 61% of patients had regular follow-up, others had occasional consultations (21%) and another 18% had deviant maintenance treatment (more than two prescribers or more than 20 mg per day of daily buprenorphine dose). Benzodiazepine consumption was much higher in the 'deviant group' (71.4%). 85% of buprenorphine prescriptions were made by GPs. 21% of GPs prescribed buprenorphine and 61% of those had only one or two maintained patients. Buprenorphine prescription by French GPs is a procedure with no particular requirements, allowing many patients to easily access maintenance treatments. However, a high risk of abuse exists, which demands extensive investigation and evaluation of these practices.

Enhanced activation of B cells in a granulocyte colony-stimulating factor-mobilized peripheral blood stem cell graft

In a randomized study that compared human leucocyte antigen-identical allogeneic granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cell (PBSC) versus bone marrow (BM) transplantation, the expression of activation markers, CD23, CD25 and CD45RO by B cells, was compared in blood before and after G-CSF mobilization and in PBSC versus BM grafts. The fractions of CD23+ and CD25+ B cells were higher in PBSC than in BM grafts. Moreover, we observed a G-CSF-induced increase in B-cell fractions in blood as well as in PBSC grafts when compared with BM grafts. Such an enhanced B-cell activation could contribute to the accelerated kinetics of immuno-haematological reconstitution, the occurrence of acute haemolysis in the ABO minor incompatibility setting, as well as the increased incidence of chronic graft-versus-host disease observed after PBSC transplantation.

Influence of the hematopoietic stem cell source on early immunohematologic reconstitution after allogeneic transplantation

Several acute hemolysis episodes, sometimes lethal, have been recently described after transplantation of allogeneic peripheral blood hematopoietic stem cells (PBHSCs). Hemolysis resulted from the production of donor-derived antibodies (Abs) directed at ABO antigens (Ags) present on recipient red blood cells (RBCs). A multicenter randomized phase III clinical study comparing allogeneic PBHSC transplantation (PBHSCT) versus bone marrow hematopoietic stem cell transplantation (BMHSCT) has been conducted in France. In the course of this study, serum anti-A and/or anti-B Ab titers were compared before the conditioning regimen and on day +30 after transplantation in 49 consecutive evaluable PBHSCT (n = 21) or BMHSCT (n = 28) recipients. PBHSCT resulted in a higher frequency of increased anti-A and/or anti-B Ab titers 30 days after transplantation as compared to BMHSCT: 8 (38%) of 21 versus 3 (11%) of 28 (P =.04). In PBHSCT recipients, increased titers were observed mostly after receiving a minor ABO mismatch transplant: 5 of 7 versus 3 of 14 in the absence of any minor ABO mismatch (P =.05), whereas this was not the case after BMHSCT: 1 of 8 versus 2 of 20. Anti-A and/or anti-B serum Abs detectable at day +30 after PBHSCT were always directed against A and/or B Ags absent both on donor and recipient RBCs. Finally, 3 of 21 PBHSCT versus 0 of 28 BMHSCT recipients developed anti-allogeneic RBC Abs other than ABO (P =.07). Overall, the data strongly suggest that immunohematologic reconstitution differs significantly after granulocyte colony-stimulating factor-mobilized PBHSCT when compared to BMHSCT. Such a difference could contribute to the acute hemolysis described after PBHSCT as well as to distinct alloreactivity after PBHSCT.

Effect of granulocyte colony-stimulating factor mobilization on phenotypical and functional properties of immune cells

Some phenotypic and functional properties of lymphocytes from bone marrow or peripheral blood stem cell donors were compared in a randomized study. Lymphocyte subsets were analyzed by immunocytometry in blood harvested from bone marrow donors (n = 27) and from peripheral blood stem cell donors before and after granulocyte colony-stimulating factor mobilization (n = 23) and in bone marrow and peripheral blood stem cell grafts. Granulocyte colony-stimulating factor mobilization increased the blood T and B, but not NK, lymphocyte counts. All lymphocyte counts were approximately 10-fold higher in peripheral blood stem cell grafts than in bone marrow grafts. Analysis of CD25, CD95, HLA-DR, and CD45RA expression shows that T-cell activation level was lower after granulocyte colony-stimulating factor mobilization. Similarly, granulocyte colony-stimulating factor reduced by twofold to threefold the percentage of interferon-gamma, interleukin-2, and tumor necrosis factor-alpha-secreting cells within the NK, NK-T, and T-cell subsets and severely impaired the potential for interferon-gamma production at the single-cell level. mRNA levels of both type 1 (interferon-gamma, interleukin-2) and type 2 (interleukin-4, interleukin-13) cytokines were approximately 10-fold lower in peripheral blood stem cell grafts than in bone marrow grafts. This reduced potential of cytokine production was not associated with a preferential mobilization of so-called "suppressive" cells (CD3+CD4-CD8-, CD3+CD8+CD56+, or CD3+TCRVA24+CD161+), nor with a modulation of killer cell receptors CD161, NKB1, and CD94 expression by NK, NK-T, or T cells. Our data demonstrate in a randomized setting that quantitative as well as qualitative differences exist between a bone marrow and a peripheral blood stem cell graft, whose ability to produce type 1 and type 2 cytokines is impaired.

Allogeneic peripheral blood stem cell transplantation results in less alteration of early T cell compartment homeostasis than bone marrow transplantation

Since low T cell counts evaluated 1 month after allogeneic bone marrow transplantation (BMT) are associated with an increased risk of leukemia relapse (Powles et al., Blood 1998; 91: 3481-3486), we compared, in a randomized multicentric clinical study, the peripheral blood cells obtained 30 days after allogeneic BMT vs allogeneic G-CSF-mobilized peripheral blood stem cell transplantation (BCT) in an HLA-identical setting. T cell counts were higher 30 days after BCT (718+/-142 cells/microl, n = 20) than after BMT (271+/-53 cells/microl, n = 26, P = 0.006). However, T cells were less activated after BCT than after BMT, as demonstrated by a lower expression level of CD25 and a lower percentage of HLA-DR+ and CD95+ T cells. Furthermore, CD4+, CD8+ and CD45RA+ post-BCT T cell counts correlated with the number of cells infused with the PBSC graft, while such a correlation was not observed between post-BMT counts and BM graft cell numbers, suggesting that the intensity of post-transplant peripheral lymphoid expansion and/or deletion differed between BCT and BMT. A comparison of the input of T cells expressing different CD45 isoforms with the post-transplant cell recovery further confirmed that, within the CD4+ T cell subset, post-transplant expansions occurred at a higher level after BMT than after BCT, affecting mainly the CD4+ CD45RO+ subset. Altogether, our data demonstrate for the first time in a randomized setting that homeostasis of the T cell pool is less altered early after BCT than after BMT. This may have a strong impact on the graft-versus-leukemia (GVL) effect and subsequent relapse rate.

[Perioperative autotransfusion with salvage blood in cancer surgery]

OBJECTIVES

Intraoperative blood cells salvage using a Cell Saver technique is controversial in oncologic surgery because tumor cells could be aspirated and reinfused to the patient. The goal of this review was to discuss the risk associated with this technique, and the way to minimize it.

DATA SOURCES

A review of the literature has been made by questioning PubMed site (http://nbci.nlm.nih.gov) on the period of 1968 to 2000. The key words were: intraoperative blood salvage, blood transfusion, autologous, cancer. Cases reports have been excluded.

STUDY SELECTION

Tumor cells aspirated and reinfused have been numbered in both experimental and clinical studies. In clinical studies, the outcome after intraoperative cells salvage/reinfusion has been compared to published data or historical groups of allogeneic transfusion, all in non randomized studies.

DATA SYNTHESIS

Both experimental and clinical studies confirmed the presence of cancer cells in the blood either aspirated or reinfused. However, six clinical studies with limited number of patients did not show metastatic spread associated with Cell Saver. The addition of leukocyte filters reduces greatly this quantity of cancer cells. Irradiation of the pack did not destroy tumor cells but blocked their proliferative capacity. In the other hand, some infiltrative tumors were shown to have permanent cancer cells seeding, quantitatively superior to the seeding observed when a Cell Saver is used.

CONCLUSION

It seems reasonable to use the Cell Saver in oncologic surgery, if possible with a leukocyte filter, not only in case of unexpected major bleeding (consensus), but also in programmed cases with high risk of huge hemorrhage.

Consolidation with a busulfan-containing regimen followed by stem cell transplantation in infants with poor prognosis stage 4 neuroblastoma

Although infants with stage 4 neuroblastoma (NB) usually have a good prognosis, metastatic relapses after 1 year of age and amplification of the N-myc oncogene are established poor prognostic factors. In order to improve the survival of patients with such high-risk factors, we performed consolidation with a busulfan (600 mg/m2)-melphalan (140 mg/m2)-containing regimen followed by autologous stem cell transplantation (SCT). From 1986 to 1998, 12 patients were treated according to this strategy. Their median age at diagnosis was 9 months (1-11). Consolidation was performed after a metastatic relapse in five children, because of persistent bone metastases in one and as first-line consolidation in six patients whose tumor exhibited N-myc amplification. The 5-year EFS rate is 64. 5% (36-85%) with a median follow-up of 92 months (20-126). One toxicity-related death occurred in a very heavily pretreated patient. Hepatic veno-occlusive disease was the major side-effect that occurred in nine of 12 children. This busulfan-melphalan combination appears to dramatically improve the prognosis of these high-risk infants with metastatic NB. Given its high toxicity, indications for this consolidation must be restricted to high-risk infants and a lower dose of busulfan (480 mg/m2) is recommended in children weighing less than 10 kg. Bone Marrow Transplantation (2000) 25, 937-942.

[Ultimate pre-transfusion control: evaluation of seven appliances]

The transfusion unit of the Institut Gustave Roussy has tested seven pre-transfusion ABO control devices registered at the Agence française de sécurité sanitaire et des produits de santé. Determination of the optimal plan to replace the existing plan in our institution was the primary objective of this study. A significant heterogeneity was observed among tested devices. None of the tested plans fulfilled all the desired quality criteria.

Allogeneic peripheral blood hematopoietic stem cell transplantation: guidelines for red blood cell immuno-hematological assessment and transfusion practice.Société Française de Greffe de Moelle

Allogeneic peripheral blood hematopoietic stem cell transplantation (PBSCT) is presently being evaluated in a French randomized study comparing peripheral blood vs bone marrow. Cases of potentially lethal acute hemolysis have recently been reported after allogeneic PBSCT in the presence of a 'minor' ABO incompatibility. Patients were frequently transfused with recipient-compatible and donor-incompatible RBC and usually did not receive methotrexate in addition to cyclosporin A for graft-versus-host disease (GVHD) prophylaxis. In order to homogenize immuno-hematological (IH) assessment and transfusion practices within our protocol, we made proposals to 25 allo-transplant French centers on the following aspects: pre-inclusion IH assessment, IH exclusion criteria, transfusion rules, post-transplant IH surveillance and treatment of hemolysis. Analysis of responses to our proposals led to the elaboration of guidelines which were approved and implemented by the French Bone Marrow Transplantation Society (SFGM). Pre-inclusion IH testing includes mandatory detection and titration of anti-RBC allo-Ab, as well as titration of anti-A and anti-B Ab. The presence in the donor of an anti-A (group A or AB recipients), anti-B (group B or AB recipients) Ab with a titer >1/32 or the presence of allo-Ab against Rh, Kell, Fya, Fyb, Jka, Jkb, Ss Ag present on recipient RBC is an exclusion criterion for the protocol. ABO and RhD compatibility of RBC blood products with both HSC donor and recipient is mandatory. A similar compatibility is also required for Rh (other than D) and Kell Ag. If not possible, compatibility of RBC blood products with the HSC donor is mandatory. Lastly, guidelines regarding post-transplantation IH follow-up as well as acute hemolysis treatment have been elaborated. The implementation of these guidelines should contribute to enhancing the quality of transfusion practice after PBSCT. Such an approach will be applied to other aspects of transfusion medicine in the setting of HSC transplantation. Bone Marrow Transplantation(2000) 25, 507-512.

Implementation of a specific approval process for blood-components prescription

We implemented a systematic computer-assisted validation process for transfusion prescriptions to improve transfusion safety. Assessment of this new approach indicates good adoption of validated transfusion guidelines and a reduction of exposure to blood products and overall costs.

[What present strategies are helpful in improving transfusion safety in France?]

Transfusion safety rests on measures ensuring that patients are transfused in accordance with the requirements of state-of-the-art scientific knowledge. This strict attitude is part of a quality approach which now applies to all fields of health. Transfusion is historically characterized by its ambivalence: it was the first medical discipline which integrated Quality Assurance concepts, it was also the first which proved unable to respond adequately in the face of uncontrolled risks. Today transfusion must create a system to rapidly: identify any risk, whether emergent or hypothetical; decide which action should be taken; monitor and assess corrective action; study the medico-economic impact of the whole approach. Quality assurance applies to every stage of the transfusion process, from blood donor to labile blood component recipient. This includes blood donor selection and biological control, labile blood component processing, qualification, transport and conditioning, prescription and distribution of blood components and transfused patient follow-up of. Quality controls, "safety locks", must be implemented at every stage to allow early problem detection, thus avoiding potentially dangerous attitudes and guaranteeing transfusion quality all along the process. Medical prescriptions must follow similar rules and meet Good Practice requirements defined by members of the medical and scientific community. A transfusion should not be prescribed unless it is absolutely necessary. In addition to sanitary surveillance, scientific surveillance must also be implemented to help transferring the findings of fundamental research to transfusion activities and continuously improve transfusion safety. INSERM is initiating sociological studies to identify and better understand donors' attitudes leading to risks. More sensitive tests based on nucleic acid amplification should reduce the incidence of residual viral risks. Various viral cell derivative inactivation techniques are being evaluated: the idea is to remove antigens to suppress the risk of post-transfusion alloimmunization. Numerous R&D; programs address substitution products. Transfusion safety requires all actors in the field of health being equally involved. Putting together experiences and know-how will continuously strengthen the quality approach adopted in transfusion.

[Transfusion medicine in adults. Perspectives]

ENHANCED SURVEILLANCE: Safety in transfusion medicine involves all the different procedures designed to guarantee safe transfusion in accordance with standards established on the current scientific knowledge. It is thus crucial to continuously monitor scientific advances in order to transfer progress in fundamental research as rapidly as possible to transfusion applications and thus maintain the highest level of safety. RISK REDUCTION: The risk of residual viral contamination might be additionally reduced by the introduction of genomic screening. Several virus inactivation processes are currently under evaluation for products derived from blood cells. The risk of post-transfusion alloimmunization might be reduced by eliminating or masking antigens (immunogens). SUBSTITUTION PRODUCTS: There are several ongoing research and development programs concerning substitution products. Products under study include perfluocarbon emulsions, hemoglobin solutions, membrane fragments, and platelet substitutes.

[Indications and utilization of labile blood products]

FUNDAMENTAL PRINCIPLES: Rigorous prescription of labile blood products is a fundamental step in assuring safe transfusion. The clinician must avoid all unnecessary transfusions and choose the most adapted blood product to meet the patient's clinical requirements. TRANSFUSION THERAPY: The patient's immunological situation, past history, prognosis, and potential need for future transfusions must be taken into account in a global approach aimed at determining which transfusion product is most adapted for each individual patient. PACKED RED CELLS: Packed red cells should be prescribed after evaluating the risk of tissue hypoxia in light of the patient's clinical situation. Restrictions on transfusion should be particularly drastic if the anemic state could respond to specific treatment (vitamin B12, iron, folic acid, erythropoietin). PLATELETS: There has been considerable development in platelet transfusion over the last few years, particularly in onco-hematology. Nevertheless, very few clinical studies are available for determining which cases require curative transfusion (solely in case of blood loss) and which situations require preventive transfusion (standard versus apheresis products). The platelet threshold indicating transfusion remains a subject of wide debate. FROZEN FRESH PLASMA: In France, regulatory indications for frozen fresh plasma were established by a ministerial decree and concern situations where a plasma fraction substitution product (medically derived blood product) cannot be prescribed. WHITE BLOOD CELL: The transfusion of this type of product should be reserved for clinical situations determined on a consensus basis between clinicians and hemobiologists.