Alemtuzumab-induced immune-mediated thrombotic thrombocytopenic purpura: A newly described drug-related autoimmune disease.

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare and life-threatening disease that may result from drug exposure. We report a case of iTTP occurring in a 39-year-old patient, 45 months following introduction of the anti-CD52 lymphoid cell depleting monoclonal antibody alemtuzumab, to treat a relapsing-remitting multiple sclerosis. Treatment consisted in plasma exchange, corticosteroids and caplacizumab, allowing clinical remission 3 months after the diagnosis, attested by the absence of thrombocytopenia and recovery of ADAMTS-13 activity. As other autoimmune disorders, iTTP may occur following alemtuzumab. This diagnosis should be suspected in patients with features of thrombotic microangiopathy following this treatment.

Type I interferon response and vascular alteration in chilblain-like lesions during the COVID-19 outbreak.

BACKGROUND: The outbreak of chilblain-like lesions (CLL) during the COVID-19 pandemic has been reported extensively, potentially related to SARS-CoV-2 infection, yet its underlying pathophysiology is unclear. OBJECTIVES: To study skin and blood endothelial and immune system activation in CLL in comparison with healthy controls and seasonal chilblains (SC), defined as cold-induced sporadic chilblains occurring during 2015 and 2019 with exclusion of chilblain lupus. METHODS: This observational study was conducted during 9-16 April 2020 at Saint-Louis Hospital, Paris, France. All patients referred with CLL seen during this period of the COVID-19 pandemic were included in this study. We excluded patients with a history of chilblains or chilblain lupus. Fifty patients were included. RESULTS: Histological patterns were similar and transcriptomic signatures overlapped in both the CLL and SC groups, with type I interferon polarization and a cytotoxic-natural killer gene signature. CLL were characterized by higher IgA tissue deposition and more significant transcriptomic activation of complement and angiogenesis factors compared with SC. We observed in CLL a systemic immune response associated with IgA antineutrophil cytoplasmic antibodies in 73% of patients, and elevated type I interferon blood signature in comparison with healthy controls. Finally, using blood biomarkers related to endothelial dysfunction and activation, and to angiogenesis or endothelial progenitor cell mobilization, we confirmed endothelial dysfunction in CLL. CONCLUSIONS: Our findings support an activation loop in the skin in CLL associated with endothelial alteration and immune infiltration of cytotoxic and type I IFN-polarized cells leading to clinical manifestations.

An open conformation of ADAMTS-13 is a hallmark of acute acquired thrombotic thrombocytopenic purpura.

Essentials Conformational changes in ADAMTS-13 are part of its mode-of-action. The murine anti-ADAMTS-13 antibody 1C4 discriminates between folded and open ADAMTS-13. ADAMTS-13 conformation is open in acute acquired thrombotic thrombocytopenic purpura (TTP). Our study forms an important basis to fully elucidate the pathophysiology of TTP. SUMMARY: Background Acquired thrombotic thrombocytopenic purpura (aTTP) is an autoimmune disorder characterized by absent ADAMTS-13 activity and the presence of anti-ADAMTS-13 autoantibodies. Recently, it was shown that ADAMTS-13 adopts a folded or an open conformation. Objectives As conformational changes in self-antigens play a role in the pathophysiology of different autoimmune diseases, we hypothesized that the conformation of ADAMTS-13 changes during acute aTTP. Methods Antibodies recognizing cryptic epitopes in the spacer domain were generated. Next, the conformation of ADAMTS-13 in 40 healthy donors (HDs), 99 aTTP patients (63 in the acute phase versus 36 in remission), 12 hemolytic-uremic syndrome (HUS) patients and 63 sepsis patients was determined with ELISA. Results The antibody 1C4 recognizes a cryptic epitope in ADAMTS-13. Therefore, we were able to discriminate between a folded and an open ADAMTS-13 conformation. We showed that ADAMTS-13 in HDs does not bind to 1C4, indicating that ADAMTS-13 circulates in a folded conformation. Similar results were obtained for HUS and sepsis patients. In contrast, ADAMTS-13 of acute aTTP patients bound to 1C4 in 92% of the cases, whereas, in most cases, this binding was abolished during remission, showing that the conformation of ADAMTS-13 is open during an acute aTTP episode. Conclusions Our study shows that, besides absent ADAMTS-13 activity and the presence of anti-ADAMTS-13 autoantibodies, an open ADAMTS-13 conformation is also a hallmark of acute aTTP. Demonstrating this altered ADAMTS-13 conformation in acute aTTP will help to further unravel the pathophysiology of aTTP and lead to improved therapy and diagnosis.

Amplified endogenous plasmin activity resolves acute thrombotic thrombocytopenic purpura in mice.

Essentials Plasmin is able to proteolyse von Willebrand factor. It was unclear if plasmin influences acute thrombotic thrombocytopenic purpura (TTP). Plasmin levels are increased during acute TTP though suppressed via plasmin(ogen) inhibitors. Allowing amplified endogenous plasmin activity in mice results in resolution of TTP signs. SUMMARY: Background Thrombotic thrombocytopenic purpura (TTP) is an acute life-threatening pathology, caused by occlusive von Willebrand factor (VWF)-rich microthrombi that accumulate in the absence of ADAMTS-13. We previously demonstrated that plasmin can cleave VWF and that plasmin is generated in patients during acute TTP. However, the exact role of plasmin in TTP remains unclear. Objectives Investigate if endogenous plasmin-mediated proteolysis of VWF can influence acute TTP episodes. Results In mice with an acquired ADAMTS-13 deficiency, plasmin is generated during TTP as reflected by increased plasmin-α2-antiplasmin (PAP)-complex levels. However, mice still developed TTP, suggesting that this increase is not sufficient to control the pathology. As mice with TTP also had increased plasminogen activator inhibitor 1 (PAI-1) levels, we investigated whether blocking the plasmin(ogen) inhibitors would result in the generation of sufficient plasmin to influence TTP outcome in mice. Interestingly, when amplified plasmin activity was allowed (α2-antiplasmin-/- mice with inhibited PAI-1) in mice with an acquired ADAMTS-13 deficiency, a resolution of TTP signs was observed as a result of an increased proteolysis of VWF. In line with this, in patients with acute TTP, increased PAP-complex and PAI-1 levels were also observed. However, neither PAP-complex levels nor PAI-1 levels were related to TTP signs and outcome. Conclusions In conclusion, endogenous plasmin levels are increased during acute TTP, although limited via suppression through α2-antiplasmin and PAI-1. Only when amplified plasmin activity is allowed, plasmin can function as a back-up for ADAMTS-13 in mice and resolve TTP signs as a result of an increased proteolysis of VWF.

Nocardia nova sphenoid sinusitis and infratemporal fossa abscess.

INTRODUCTION: Nocardia sinusitis is exceptional, as a Medline search revealed only one published case. The authors report a case of sphenoid sinusitis complicated by infratemporal fossa abscess, which raised several diagnostic problems. CASE REPORT: The patient was referred with temporal headache, subacute trigeminal neuralgia and subsequent infectious syndrome. Computed tomography imaging revealed left sphenoid sinusitis with osteolysis and infratemporal fossa abscess, as well as suspicious lung nodules suggestive of the initial site of infection. Bacteriological specimens obtained by endoscopic sphenoidotomy confirmed the presence of Nocardia nova. A favourable outcome was observed in response to targeted antibiotic therapy. DISCUSSION AND CONCLUSION: Sphenoid sinusitis with infratemporal fossa abscess is an exceptional mode of presentation of nocardiosis, illustrating the polymorphic clinical features of this disease. Bacteriological examination of samples taken directly from the organ concerned, in this case, by sphenoidotomy, is the only formal diagnostic criterion. Antibiotic therapy with intravenous imipenem/amikacin, followed by oral sulfamethoxazole/trimethoprim (Bactrim Forte(®)) for several months, is the key to successful management.

Smoking cessation attempts: is it useful to treat hard core smokers?

BACKGROUND: Hard core smokers have been studied in many countries but only a few trials have compared the effectiveness of smoking cessation with other smokers. The objective of this study was to compare the frequencies of success in smoking cessation between hard-core smokers and other smokers. METHODS: Data were collected in Clermont-Ferrand from the Emile Roux dispensary 'Pneumology and Tobaccology Centre' between 1999 and 2009. Assistance with smoking cessation was proposed to 1367 patients but only 1296 patients were included: 219 HCS and 1077 other smokers. Smoking cessation was considered a success when patients were abstinent 6 months after the beginning of cessation. The profiles of the two types of smokers were compared using Chi square test and Student's t test. Multivariate logistic regression was used to investigate the association between the smoking cessation result and the type of smokers. RESULTS: HCS more frequently consumed other psychoactive substances (41.1 % vs 25.7 % for other smokers; p < 0.001). Current depression was more frequent in HCS (46.6 % vs 34.8 % for other smokers; p = 0.001). Smoking cessation was less frequent in HCS (45.2 % vs 56.5 % for other smokers ; p = 0.002). In multivariate analysis, after controlling for other factors, the frequency of smoking cessation was not significantly associated with the type of smokers (p = 0.47). After limiting to initial factors (present before the beginning of smoking cessation), the frequency of smoking cessation was still not significantly associated with the type of smokers (p = 0.78). CONCLUSION: Smoking cessation is possible for hard core smokers, who should be treated as other types of smokers taking into account other factors:the problem is how to encourage them to try to stop smoking.

[Mild hemophilia A fortuitously discovered during Henoch-Schönlein purpura]. / Découverte fortuite d'une hémophilie A mineure à l'occasion d'un purpura rhumatoïde.

Henoch-Schönlein purpura is a common form of immunological vasculitis in children. Hemophilia A is a genetic disorder, inherited in a X-linked recessive pattern, and characterized by spontaneous hemorrhage or prolonged bleeding due to factor VIII deficiency. The clinical signs depend on the severity of factor VIII deficiency. We herein report the case of a 4-year-old boy admitted to the emergency room for typical rheumatoid purpura, associated with a lengthening of aPTT, whose exploration had uncovered mild hemophilia A. Laboratory assays should explore lengthening of aPTT: firstly the presence of lupus anticoagulant without bleeding risk, in an inflammatory context; secondly a deficiency of VWF and one of the factors involved in the extrinsic coagulation pathway associated with bleeding risk.

Survey of clinical isolates of diarrhoeogenic Escherichia coli: diffusely adhering E. coli strains with multiple adhesive factors.

A total of 335 Escherichia coli strains were isolated from sporadic cases of aqueous diarrhoea in patients hospitalized in Clermont-Ferrand, France, during 1991 and 1992. Many of these strains belonged to the diffusely adhering E. coli (DAEC) group, since 51 of them (15.2%) hybridized with the daaC probe corresponding to the accessory gene of the F1845 adhesin and 13 (3.9%) with the AIDA-I (adhesin involved in diffuse adhesion-I) structural gene. The other pathogenic E. coli groups were weakly represented: 0.6% (2 strains) of enterotoxigenic E. coli (ETEC), 0.6% (2 strains) of enterohaemorrhagic E. coli (EHEC) and 3.9% (13 strains) of enteroaggregative E. coli (EAggEC). Neither enteropathogenic E. coli (EPEC) nor enteroinvasive E. coli (EIEC) were isolated in our study period. Among the DAEC strains studied, we described two major surface proteins of 16 and 29 kDa. We showed that the 16-kDa protein (CF16K) was involved in adhesion in vitro to Caco-2 and HEp-2 cells. Pretreatment of bacteria with anti-CF16K serum or of Caco-2 cells with purified CF16K greatly decreased the adhesion of the E. coli CF1085 strain producing the CF16K protein to both cell types. The CF16K adhesive factor was found in 9.5% (33 strains) of the 335 E. coli strains studied by colony immunoblot assays with anti-CF16K serum. Twelve strains producing CF16K hybridized with the daaC probe, indicating that the CF16K is not related to the Dr family adhesins which recognized the Dr blood group antigen as receptor. The 29-kDa protein, isolated from 9 strains out of the 335 studied (5.1%), was identified as the CS31A antigen by Western blot assay using anti-CS31A serum and by hybridization experiments with a CS31A DNA probe. This antigen is routinely observed in septicaemic or enterotoxigenic bovine E. coli strains. We showed that a single diarrhoeogenic E. coli strain could harbour at least two adhesive factors, since 36% of CF16K E. coli strain producers and 68.4% of CS31A E. coli strain producers hybridized with the daaC DNA probe.

Probiotic activities of Lactobacillus casei rhamnosus: in vitro adherence to intestinal cells and antimicrobial properties.

The interest of probiotics as remedies for a broad number of gastrointestinal and other infectious diseases has gained wide interest over the last few years, but little is known about their underlying mechanism of action. In this study, the probiotic activities of a human isolate of Lactobacillus casei subsp. rhamnosus strain (Lcr35) were investigated. Using intestinal Caco-2 cell line in an in vitro model, we demonstrated that this strain exhibited adhesive properties. The inhibitory effects of Lcr35 organisms on the adherence of three pathogens, enteropathogenic Escherichia coli (EPEC), enterotoxigenic E. coli (ETEC) and Klebsiella pneumoniae, were determined. A decrease in the number of adhering pathogens was observed, using either preincubation, postincubation or coincubation of the pathogens with Lcr35. Moreover, the antibacterial activities of cell-free Lcr35 supernatant was examined against nine human pathogenic bacteria, ETEC, EPEC, K. pneumoniae, Shigella flexneri, Salmonella typhimurium, Enterobacter cloacae, Pseudomonas aeruginosa, Enterococcus faecalis and Clostridium difficile. The growth of all strains was inhibited, as measured by determining the number of viable bacteria over time, but no bactericidal activity was detected in this in vitro assay. Together, these findings suggest that this probiotic strain could be used to prevent colonization of the gastrointestinal tract by a large variety of pathogens.

Involvement of P-glycoprotein in an in vitro blood-brain barrier model.

The P-glycoprotein (P-gp) multidrug transporter is present at the luminal face of the brain capillary endothelial cells that contribute to the blood-brain barrier. To study its role in transendothelial anticancer drug transport, we made use of a co-culture system formed of bovine brain capillary endothelial cells and astrocytes which allows the in vitro maintenance of specialized properties of the brain endothelial cells, including expression of P-gp as assessed by Northern and Western blot analyses. Vinblastine, an anticancer drug substrate for P-gp and known not to enter the brain, was found to be poorly transferred across the endothelial cell monolayer. This low vinblastine transport was however strongly increased in the presence of verapamil, a well known P-gp blocker. Moreover, verapamil was shown to increase the accumulation of the anticancer drug in the brain endothelial cells through inhibition of drug efflux. These results suggest that P-gp activity evidenced in the co-culture model is involved in the low transendothelial transport of vinblastine, thus supporting the conclusion that P-gp expressed at the blood-brain barrier level may prevent xenobiotics, including anticancer drugs, from entering the central nervous system.

Nucleotide sequence of the nfaA gene encoding the antigen 8786 adhesive factor of enterotoxigenic Escherichia coli.

The nucleotide sequence of a 714-bp DNA fragment containing the enterotoxic Escherichia coli (ETEC) adhesive factor 8786 structural gene, designated nfaA, revealed an open reading frame of 498 bp encoding a polypeptide of 166 amino acids. Primer-extension experiments showed that the nfaA gene is within a single transcription unit. No homology was found with the ETEC adhesive factors already sequenced. In contrast, a homology with Salmonella enteritidis fimbrin SEF 14 was observed.

Characterization of enteroaggregative Escherichia coli isolates.

Forty enteraggregative Escherichia coli (EAggEC) previously characterized by their ability to adhere to HEp-2 cells or/and their hybridization with the 1-kb EAggEC DNA probe were investigated for the presence of adherence factors and heat-stable enterotoxin (EAST1)-encoding genes. Only 45% of the isolates harbored the EAST1-encoding genes as detected by polymerase chain reaction. None of them hybridized with an AAF/II-encoding gene specific DNA probe and 35% (14/40) were positive in a PCR assay using primers specific for aggC, an accessory gene of the AAF/I-encoding operon. Cloning and sequence analysis of the aggA variant from one isolate, EAggEC 457, revealed 68.9% identity between its deduced amino acid sequence and those of the aggA product from the AAF/I-producing reference strain, E. coli 17.2. No major protein subunit was detected at the surface of EAggEC 457 compared to the bacterial surface extract of E. coli 17.2.

Competitive exclusion of diarrheagenic Escherichia coli (ETEC) from human enterocyte-like Caco-2 cells by heat-killed Lactobacillus.

Diarrheagenic Escherichia coli (ETEC) bearing CFA/I or CFA/II adhesive factors specifically adhere onto the brush border of the polarized epithelial human intestinal Caco-2 cells in culture. Heat-killed Lactobacillus acidophilus strain LB, that adheres onto Caco-2 cells, inhibits diarrheagenic Escherichia coli adhesion in a concentration-dependent manner. Since the L. acidophilus does not express ETEC-CFA adhesive factors, it can be postulated that the heat-killed L. acidophilus LB cells inhibit diarrheagenic E. coli attachment by steric hindrance of the human enterocytic ETEC receptors.

Characteristics and diffusion in the rabbit of a phage for Escherichia coli 0103. Attempts to use this phage for therapy.

A bacteriophage for Escherichia coli 0103 was isolated during a study on E. coli diarrhoea in intensive breeding units of rabbits. The phage had an isometric head and a short tail and resembled coliphage N4 (Podoviridae). It had a very narrow host range and seemed to be specific for serogroup 0103, suggesting that it might be used for preliminary identification of E. coli strains of this serogroup instead of the usual slide agglutination. In view of its possible use as a therapeutic phage, we investigated its dissemination in rabbit organs after oral administration. The phage persisted in the spleen for at least 12 days. However, in vivo studies showed that this phage and a mixture of more virulent phages for E. coli 0103 were ineffective in preventing disease in rabbits inoculated with an enteropathogenic strain of E. coli 0103.

Selective drug transport and P-glycoprotein activity in an in vitro blood-brain barrier model.

To determine whether compounds are able to reach the neural microenvironment, a blood-brain barrier (BBB) co-culture model has been recently developed with bovine brain capillary endothelial cells and newborn rat astrocytes. In this study, the permeability of confluent endothelial cells to various compounds and the functional activity of P-glycoprotein (P-gp), an ATP-dependent pump known to efflux drugs from multidrug-resistant tumoral cells, was assessed. The permeability of the lipophilic compounds imipramine and sulpiride differed in relation to their structure. A good correlation was observed with in vivo brain extraction levels. P-gp activity was estimated by measuring the uptake of [(3)H]vinblastine by the endothelial cells, with or without verapamil, which is known to reverse drug resistance. Intracellular accumulation of the vinca alkaloid was strongly increased after addition of verapamil, suggesting that P-gp is active in these cells. These results provide further support for the use of the co-culture model of bovine brain endothelial cells and rat astrocytes to screen new centrally active drugs.

Helium-oxygen breathing in the early emergency care of acute severe asthma: a randomized pilot study.

The aim of this study was to establish whether a clinical trial, comparing helium-oxygen (HeO2) breathing to standard therapy, would be feasible during the out-of-hospital care of adult patients with severe asthma. Although the primary outcome in a definitive trial will be a decrease in morbidity, the present study primarily examined: (1) if the strategy could be successfully implemented in emergency ambulatory units; (2) if the research staff could enroll enough patients, given the resources. Nine patients were included in the conventional treatment group, and seven patients in the HeO2 group. Patients randomized to the HeO2 group breathed the mixture for a 12-hour period. Clinical and biological parameters improved for all patients. There was no trend towards a HeO2 benefit, whether during the initial out-of-hospital nor the ICU care. No patient was intubated within the study period. HeO2 breathing was considered to be simple to initiate, and no side effects were reported. In conclusion, while HeO2 breathing is easy to apply, even in the out-of-hospital setting, the few enrolled patients did not appear to benefit from this treatment. Regarding our low inclusion rate and the lack of positive effect trend, we believe that a large definitive trial will be difficult to initiate in such an emergency care setting.

Resistance to beta-lactams in Enterobacteriaceae: distribution of phenotypes related to beta-lactamase production.

Phenotypes of susceptibility to amoxycillin (Amo), ticarcillin (Tic), cephalothin (Ctn) were determined in 1366 isolates of Enterobacteriaceae by disk method and beta-lactamases were identified in 243 strains belonging to different phenotypes of amoxycillin-resistant strains. AmoR TicR CtnS strains (25%) were penicillinase producers and all of them were susceptible to the combination amoxycillin/clavulanic acid (Amo/CA) and ticarcillin/clavulanic acid (Tic/CA). Amo1/R TicS CtnR strains (12%) were cephalosporinase producers and resistance to Amo/CA was observed, except for Proteus vulgaris. AmoR TicR CtnR strains (18%) often produced two beta-lactamases (penicillinase and cephalosporinase) and they were resistant to Amo/CA; in this group, susceptibility to Tic/CA depends on the nature and the amount of the beta-lactamase produced, except for Serratia marcescens for which antibiotic resistance is probably due to other mechanisms. Tic/CA resistance was mainly found in Serratia marcescens (41%) and Enterobacter cloacae (36%).

[Verotoxin-producing Escherichia coli infections: study of its prevalence in children in the Auvergne region]. / Les infections à Escherichia coli producteurs de vérotoxines: étude de la prévalence chez l'enfant dans la région Auvergne.

Verotoxin producing Escherichia coli (VTEC) have been associated with disease outbreaks of diarrhea hemorrhagic colitis and hemolytic-uremic syndrome in humans. Contamination occurs mainly by ingestion of beef and dairy products, but water and person to person transmission have also been described. Most of the clinical signs are due to the production of Stx1 and/or Stx2 Shiga toxins, also called verotoxins. Other virulence factors include enterohemolysin, and the product of the eae gene, intimin, involved in the attaching and effacing adherence phenotype. The predominant serotype is O157:H7, but VTEC strains of more than one hundred serotypes can cause human disease. In order to determine the prevalence of VTEC infections among children in the central part of France, stool samples from hospitalized children were examined for stx1 and stx2 genes by using a polymerase chain reaction (PCR) technique. From October 1997 to September 1998, 658 stool samples were analysed: among them 19 (3%) were stx-PCR positive. Only 8 children out of 19 had diarrhea, and for 5 of them, an enteric pathogen other than VTEC was isolated. VTEC strains were isolated from 10 samples: most of the isolates did not produce verotoxins at a high level, and they did not belong to serotypes associated with pathogenicity, which might explain the absence of relationship between VTEC isolation and pathogenicity in our study.

[In vitro comparative study of piperacillin-aminoglycosides combinations against Enterococci and Enterobacteriaceae]. / Etude comparative in vitro d'associations pipéracilline-aminosides face aux entérocoques et aux entérobactéries.

The hundred and ninety-two combinations were tested against 17 strains chosen from the results of MIC determination (disc method): 5 enterococci exhibiting low level resistance (r) or high level resistance (R) to streptomycin (S) and gentamicin (G): 2 strains Sr Gr, 2 strains SR Gr and 1 strain Sr GR; 12 enterobacteria chosen for their resistance phenotypes to beta-lactams and aminoglycosides and because they are the most frequent clinical isolates: 2 strains Amos Tics Ctns (group 1), 4 strains AmoR Tics CtnR (gr. II), 4 strains AmoR TicR Ctns (gr. III) and 2 strains AmoR TicR CtnR (gr. IV). MIC and MBC were assessed for the 17 strains (Mueller Hinton broth). Combinations were carried out by a checkerboard micromethod. FBC index was calculated for each combination. Against enterococci the 50 combinations were: piperacillin versus ampicillin + aminoglycosides (streptomycin, tobramycin, amikacin, gentamicin, netilmicin). Against enterobacteria piperacillin was combined with different aminoglycosides depending on their resistance phenotypes. These combinations were compared with ticarcillin or mezlocillin or cefotaxime + aminoglycosides (total number 142). The species studied produced different results: with the enterococci Gr synergistic effects (FBC = 0.62-0.75) were rare; additive and indifferent effects were predominant. With the GR strain some antagonistic effects were observed. With the enterobacteria, in groups I and II synergistic effects were frequent and almost equivalent regardless of the beta-lactam chosen. In groups III and IV (TicR) piperacillin MICs were greater than or equal to 128 mg/l and mezlocillin MICs greater than 512 mg/l; the synergistic effects were significant (FBC from 0.25 to 0.62). beta-lactam + amikacin or netilmicin, and especially piperacillin + amikacin, were found to have the most frequent synergistic effects upon the strains tested. Mezlocillin combinations cannot be used clinically; the use of piperacillin combinations requires further discussion. On the other hand, cefotaxime + aminoglycosides combinations are active against those TicR strains.

[Associations of patients and tissue banks]. / Les associations de malades et les banques de tissus.

Research dealing with tissue is more important to day than ever. Techniques of molecular genetics have indeed permitted the identification of a large number of new proteins that have now to be localised in the tissue and in the cell, in health and disease. This step has to be made in order to elaborate the adequate animal models in which new therapeutics can be tested. In France, however, human tissue samples have become difficult to obtain. Many factors contributed to this situation. Autopsies are now exceptionally performed. Doctors feel confident in their diagnosis and express rarely the need to control it. Families are opposed to post mortem more strongly than before, especially when the reasons for performing it can not be explained before the death of the patient. French law now makes the explicit consent of the patient mandatory before any research. This practically limits all post mortem investigations to those that had been planned before death. The possibility of giving tissue post mortem to allow research has to be publicised, particularly by associations of patients. The organisation that should manage to collect and store the samples at a large scale and over the whole country is lacking. Its structure is still discussed: should it be supported by the state itself, by private funding, possibly by the associations of patients themselves? Patients Associations are ready to play a crucial role: they realised that the present system was inefficient, they are presently trying to organise tissue banks; they will finally have to explain to their members why they should care for research, how they could help and how they will have to accept the absence of immediate spectacular results.