The French High Authority of Health (HAS) and National Drug Safety (ANSM) agencies recommendations issued in 2014, the French General Direction of Health (DGS) instruction published in November 2021, the French National Blood Bank (EFS) guidelines and the data available in the literature globally define "good transfusion practices" but provide little information about the immuno-hematological and transfusion management of patients who have received an allogeneic hematopoietic stem transplantation (allo-HCT). The aim of this workshop was to harmonize these practices in situations for which there are currently no recommendations. In order to anticipate possible transfusion issues after allo-HCT, we recommend performing, before the transplantation, an extended red blood cell phenotyping of the donor and a detection of HLA alloimmunization in the recipient. We recommend to systematically perform for minor ABO mismatches: a direct antiglobulin test between D8 and D20, and for major ABO mismatches; a titration of anti-A/anti-B antibodies and an erythrocyte chimerism at D100. At one-year post-transplant, we recommend carrying out an erythrocyte chimerism to allow, if necessary, the update of transfusion counselling (RH phenotype, irradiation of packed red blood cells).

Relapse after allogeneic hematopoietic cell transplantation (allo-HCT) remains a major concern because it is associated with poor survival. A second allo-HCT is a valid option in this situation. During the 13th annual harmonization workshops of the francophone Society of bone marrow transplantation and cellular therapy (SFGM-TC), a designated working group reviewed the literature in order to update the second allo-HCT recommendations elaborated during the previous workshop (2016). The main indication for a second allo-HCT remains relapse of initial hematologic malignancy. Disease status; complete remission (CR), and relapse time after the first allo-HCT>6 months impact positively the overall survival of patients after the second allo-HCT. Donor change is a valid option, particularly if there is HLA loss on leukemic cells after a first haploidentical or following a mismatched allo-HCT is documented. Reduced intensity conditioning is recommended, while a sequential protocol is a reasonable option in patients with proliferative disease. A post-transplant maintenance strategy after hematological recovery is recommended as soon as day 60, even if the immunosuppressive treatment has not yet been stopped. Hypomethylating agents, and targeted therapies such as anti FLT3, anti BCL2, anti-IDH1/2, TKI, anti-TP53, anti-CD33, anti-CD19, anti-CD22, anti-CD30, check point inhibitors, and CAR-T cells can be used as a bridge to transplant or as an alternative treatment to the second allo-HCT.

Cystinosis is an autosomal recessive metabolic disease characterized by lysosomal accumulation of cystine in all the cells of the body. Infantile cystinosis begins in infancy by a renal Fanconi syndrome and eventually leads to multi-organ failure, including the kidney, eye, thyroid, muscle, and pancreas, eventually causing premature death in early adulthood. The current treatment is the drug cysteamine that only delays the progression of the disease. We identified the gene involved, CTNS, and showed that the encoded protein, cystinosin, is a proton-driven cystine transporter. We generated a mouse model of cystinosis, the Ctns-/- mice, that recapitulates the main disease complications. The goal was next to develop a gene therapy approach for cystinosis. We used bone marrow stem cells as a vehicle to bring the healthy CTNS gene to tissues, and we showed that wild-type hematopoietic stem and progenitor cell (HSPC) transplantation led to abundant tissue integration of bone marrow-derived cells, significant decrease of tissue cystine accumulation and long-term kidney, eye and thyroid preservation. We then developed an autologous transplantation approach of HSPCs modified ex vivo using a lentiviral vector to introduce a functional CTNS cDNA, and showed its efficacy in Ctns-/- mice. We conducted the pharmacology/toxicology studies, developed the manufacturing process using human CD34+ cells, and design the clinical trial. We received Food and Drug Administration (FDA)-clearance to start a phase 1/2 clinical trial for cystinosis in December 2018. Six patients have been treated so far. In this review, we describe the path to go from the gene to a gene therapy approach for cystinosis.

Elderly patients with acute myeloid leukemia, ineligible for intensive chemotherapy, have long had a very poor prognosis and have always represented one of the main patient populations included in early phase clinical research trials. In recent years, many molecules have shown very interesting efficacy, often targeted therapies whose indication is based on a specific mutation profile (gilteritinib, ivosidenib), or mutation-independent (venetoclax), but also drugs whose indication is based on a specific biomarker (tamibarotene) or on new generation immunotherapies targeting macrophages (magrolimab) or other immune effectors while targeting leukemic cells resulting in forced immunological synapse (flotetuzumab) or activation of lymphocyte effectors associated with inhibition of the AML cells' stem signature in their microenvironment (cusatuzumab sabatolimab). All of these new strategies are discussed in this review, as well as the challenges of this frail population, which has benefited in recent months from all the major advances in the field, questioning in a second phase the modification of practices in younger patients.

Since 2021, assisted reproductive technologies (ART) are available to infertile couples, but also to single women and female couples. The process of in vitro fertilization (IVF) has allowed to cross the threshold of 5 million births worldwide, between 1978 and 2013. However, the failure rate per each IVF cycle is estimated to be around 75%. Therefore, there is a need to better understand human embryonic development in order to improve the success rate of IVF. Study models have evolved significantly in recent years: development of embryo culture, sequencing of the transcriptome of individualized cells, discovery of culture conditions for naive pluripotent stem cells and generation of blastoids. Here, we review these recent advances in human embryo modeling that establish a new knowledge base for improving ART.

Like the "nurse practitioner" in Anglo-Saxon countries, the French health authority validated on January 2016 the creation of an intermediate grade called advanced practice nurse (APN). They are authorized to carry out an assessment of the person's state of health, through a complete clinical examination. They can also prescribe additional examinations necessary for the monitoring of the pathology, and carry out certain acts for diagnostic and/or therapeutic purposes. Given the specificities of cellular therapy patients, the content of university professional training doesn't seem sufficient to assure an optimal management by the APN of these patients. The Francophone society of bone marrow transplantation and cellular therapy (SFGM-TC) had already published two works regarding what was initially called "the transfer of skills" between doctors and nurses in the follow-up of transplant patients. In the same way, this workshop attempts to address the question of the place of APNs in the management of patients undergoing cellular therapy treatment. Beyond a delegation of tasks as proposed by the cooperation protocols, this workshop produces recommendations to allow an autonomous activity of the IPA in the follow-up of these patients, in close collaboration with the medical team.

Asthma is a frequent respiratory disease, with severe asthma occurring in 3 to 5% of cases. Chronic inflammation of the bronchial epithelium is essential to its pathophysiology. When activated by the bronchial environment, the peripheral sensory nervous system contributes to inflammation of the airways. However, due to a lack of reliable models, the mechanisms of action remain largely unknown. Using induced pluripotent stem cells reprogrammed from blood cells, we have set up a model of bronchial epithelium innervated by sensory neurons. This model will ensure better understanding of the mechanisms of action underlying neurogenic inflammation.

This review intends to introduce the changes of the new Bioethics law in the reproductive field and its application in French ART centers.

We present the case of a 12 year old child with a limp. The diagnostic work-up reveals splenomegaly, multifocal bone involvement and abdominal adenopathies. A biopsy of an intra-abdominal lesion shows a lymphoid mass with a nodular architecture composed of poorly defined nodules. We identify large cells with irregular, sometimes poly-lobulated nuclei with a particular immunohistochemical profile. Those "pop-corn" cells are positive for CD20, CD79a, pax-5 and bcl-6 and are negative for CD15, CD30, bcl-2, TdT, CD56 and EMA. There is a diffuse follicular helper T cell population that is located in between the tumour cells. The overall picture is indicative of a nodular lymphocyte predominant Hodgkin lymphoma. Advanced stage of this disease is rare in children and there is currently little data to guide optimal treatment. Because of a stage IV disease, the patient is treated with chemotherapy after which complete metabolic remission is observed. 3.5 years after the initial diagnosis, our patient relapses. He is treated with chemotherapy and an autologous peripheral blood stem cell transplantation. He remains in complete remission since then. This case illustrates the favorable prognosis of the disease even after relapse.

The isolation of insulin from the pancreas and its purification to a degree permitting its safe administration to type 1 diabetic patients were accomplished 100 years ago at the University of Toronto by Banting, Best, Collip and McLeod and constitute undeniably one of the major medical therapeutic revolutions, recognized by the attribution of the 1923 Nobel Prize in Physiology or Medicine to Banting and McLeod. The clinical spin off was immediate as well as the internationalization of insulin's commercial production. The outcomes regarding basic research were much slower, in particular regarding the molecular mechanisms of insulin action on its target cells. It took almost a half-century before the determination of the tri-dimensional structure of insulin in 1969 and the characterization of its cell receptor in 1970-1971. The demonstration that the insulin receptor is in fact an enzyme named tyrosine kinase came in the years 1982-1985, and the crystal structure of the intracellular kinase domain 10 years later. The crystal structure of the first intracellular kinase substrate (IRS-1) in 1991 paved the way for the elucidation of the intracellular signalling pathways but it took 15 more years to obtain the complete crystal structure of the extracellular receptor domain (without insulin) in 2006. Since then, the determination of the structure of the whole insulin-receptor complex in both the inactive and activated states has made considerable progress, not least due to recent improvement in the resolution power of cryo-electron microscopy. I will here review the steps in the development of the concept of hormone receptor, and of our knowledge of the structure and molecular mechanism of activation of the insulin receptor.

The COVID-19 pandemic disorganized the allogeneic stem cell transplantation activities all over the world, with the necessity to cryopreserve allografts to secure the procedure for both the recipient and the donor. Cryopreservation, usually anecdotal, has been used by all the French speaking centers; data collected from 24 centers were assessed in order to determine the impact of cryopreservation on the quality of allografts. Our analysis clearly demonstrates that increasing transit time (more than 48hours) is deleterious for CD34+ recovery, legitimates the slight increase of the requested CD34+ cell dose with respect to the average recovery rate as well as the importance of the quality control on the infused product.

The role of allogeneic hematopoietic cell transplantation (allo-HCT) after CAR T- treatment cells in hematologic malignancies is currently controversial. Prolonged remissions after several years of follow-up suggest that there is a curative effect of CAR T-cells therapy, whereas allo-HCT was previously considered the only curative treatment in relapse situation. The aim of this harmonization workshop is to detail the existing data in the literature on the feasibility of allo-HCT after CAR T-cells and to propose to consider allograft in selected patients with B-acute lymphoblastic leukemia (B-ALL) and diffuse large B-cell lymphoma (DLBCL). In B-ALL, various intrinsic factors (inherent to the patient, to the disease, to the type of CAR T-cells) and especially various post CAR T-cells criteria (early expansion kinetics, residual disease at D28, early loss of B-cell aplasia) should lead to consider performing allo-HCT before the occurrence of a relapse. In DLBCL, although there are risk factors for relapse at diagnosis and prior to CAR T-cells therapy, response assessed by PET-CT at three months is critical and allo-HCT cannot currently be recommended in cases of complete or partial remission. In any case, if the age is appropriate for allogeneic transplantation, HLA typing should be performed before CAR T-cells treatment in order not to delay the allo-HCT project if needed.

Acute and/or chronic graft-versus-host disease (GVHD) is a serious complication after allogeneic hematopoietic stem cell transplantation (alloHSCT). It is a multisystemic inflammatory and/or fibrotic disease that occurs when the immune cells derived from the graft (and therefore originating from the donor) recognize recipient's healthy tissues as foreign and react against them. Acute GVHD is one of the main causes of non-relapse mortality after alloHSCT. Chronic GVHD can be very disabling in its severe form and can also be responsible for late mortality, mainly due to long-term immune deficiency and opportunistic infections. In contrast, GVHD can be associated with certain beneficial effects in patients transplanted for hematological malignancies, through simultaneous «graft versus tumour» positive effects. Therefore, one of the challenges of alloHSCT is the prevention and treatment of severe forms of GVHD without losing the beneficial anti-tumour effects of the graft.

Contribution of mesenchymal stromal cell transplantation in systemic scleroderma Systemic scleroderma is a rare chronic autoimmune disease with the highest mortality rate among rheumatologic diseases. Its pathophysiology is based on three mechanisms: endothelial damage with initial vasculopathy, activation of the immune response, progressive fibrosis of the skin and various organs. Cellular therapy allows to envision new perspectives: autologous hematopoietic stem cell transplantation has been widely validated to treat severe forms of the disease, but its use is restricted to the most severely affected patients and contraindicated in advanced forms of the disease. The use of mesenchymal stromal cells, and their immunomodulatory, pro-angiogenic and anti-fibrotic properties, as well characterized in vitro and in vivo, broadens the field of possibilities. The use of mesenchymal stromal cells in targeted indications (treatment of graft versus host disease, crohn's disease fistulas, etc.) Has received market authorization and is currently being studied in systemic scleroderma with very promising results.

iPSC-derived brain and retinal organoids represent biologically relevant 3D models. A new step in the field of brain and retinal organoids was reached a few months ago with the simultaneous development of brain and eye structures from human iPS cells within the same organoid. Single-cell mRNA sequencing analyses allowed the identification of various ocular and cerebral neuronal populations and electrophysiological recordings confirm the presence of functional and electrically active neurons. The coexistence within the same organoid of different cell types from visual and brain regions and the establishment of connections between these regions raise the intriguing question of its real or potential functionality and its ability to process higher-level visual information. This unique model could also be used to further understand the development of the human visual system and associated developmental diseases.