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Heterologous polyclonal antibodies might represent an alternative to the use of convalescent plasma or monoclonal antibodies (mAbs) in coronavirus disease (COVID‐19) by targeting multiple antigen epitopes. However, heterologous antibodies trigger human natural xenogeneic antibody responses particularly directed against animal‐type carbohydrates, mainly the N‐glycolyl form of the neuraminic acid (Neu5Gc) and the α1,3‐galactose, potentially leading to serum sickness or allergy. Here, we immunized cytidine monophosphate‐N‐acetylneuraminic acid hydroxylase and α1,3‐galactosyl‐transferase (GGTA1) double KO pigs with the Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) spike receptor binding domain to produce glyco‐humanized polyclonal neutralizing antibodies lacking Neu5Gc and α1,3‐galactose epitopes. Animals rapidly developed a hyperimmune response with anti‐SARS‐CoV‐2 end‐titers binding dilutions over one to a million and end‐titers neutralizing dilutions of 1:10 000. The IgG fraction purified and formulated following clinical Good Manufacturing Practices, named XAV‐19, neutralized spike/angiotensin converting enzyme‐2 interaction at a concentration, GGTA1/CMAH double KO pigs produced high titers of XAV‐19, an anti‐SARS‐Cov‐2 RBD glyco‐humanized polyclonal antibody. XAV‐19 is presented with a high complement activation and a high neutralization potency in vitro and in cell‐based neutralization assays. XAV‐19 does not interact with human Fc gamma receptors, preventing Fc‐dependent enhancement or immune cells skewing.

International audience; Antibodies of non-human mammals are glycosylated with carbohydrate antigens, such as galactose-α-1-3-galactose (α-Gal) and N-glycolylneuraminic acid (Neu5Gc). These non-human carbohydrate antigens are highly immunogenic in humans due to loss-of-function mutations of the key genes involved in their synthesis. Such immunogenic carbohydrates are expressed on therapeutic polyclonal rabbit anti-human T-cell IgGs (anti-thymocyte globulin; ATG), the most popular induction treatment in allograft recipients. To decipher the quantitative and qualitative response against these antigens in immunosuppressed patients, particularly against Neu5Gc, which may induce endothelial inflammation in both the graft and the host. We report a prospective study of the antibody response against α-Gal and Neu5Gc-containing glycans following rabbit ATG induction compared to controls. We show a drop in the overall levels of anti-Neu5Gc antibodies at 6 and 12 months post-graft compared to the pre-existing levels due to the major early immunosuppression. However, in contrast, in a cross-sectional study there was a highly significant increase in anti-Neu5Gc IgGs levels at 6 months post-graft in the ATG-treated compared to non-treated patients(P = 0.007), with a clear hierarchy favouring anti-Neu5Gc over anti-Gal response. A sialoglycan microarray analysis revealed that the increased anti-Neu5Gc IgG response was still highly diverse against multiple different Neu5Gc-containing glycans. Furthermore, some of the ATG-treated patients developed a shift in their anti-Neu5Gc IgG repertoire compared with the baseline, recognizing different patterns of Neu5Gc-glycans. In contrast to Gal, Neu5Gc epitopes remain antigenic in severely immunosuppressed patients, who also develop an anti-Neu5Gc repertoire shift. The clinical implications of these observations are discussed.

We give existence and uniqueness results of the weak-renormalized solution for a class of nonlinear Boussinesq's systems. The main tools rely on regularity results for the Navier-Stokes equations with precise estimates on the solution with respect to the data in dimension $2$ and on the techniques involved for renormalized solutions of parabolic problems.

In this paper we prove the existence and uniqueness of a renormalized solution for nonlinear parabolic equations whose model is \begin{eqnarray} \frac{\partial b(u)}{\partial t} - div\big(a(x,t,u,\nabla u)\big)=f+ div (g), \end{eqnarray} where the right side belongs to $L^{1}(Q)+L^{p'}(0,T;W^{-1,p'}(\Omega))$, where $b(u)$ is a real function of $u$ and where $-div(a(x,t,u,\nabla u))$ is a Leray-Lions type operator with growth $|\nabla u|^{p-1}$ in $\nabla u$, but without any growth assumption on $u$.

Given a parabolic cylinder Ω × (0, T), where Ω is a bounded domain of $${\mathbb{R}^N}$$ , we consider IBV problems involving equations of the type $$b(u)_{t} - \Delta_{p} u = \mu$$ where b is a increasing C 1-function and μ is a diffuse measure. We prove the existence and uniqueness of a renormalized solution for this class of nonlinear parabolic equations.

This Note deals with the modeling of a structure made of straight elastic rods whose thickness tends to 0. We show that, upon an adequate scaling, the infimum of the total elastic energy tends to the minimum of a functional which depends on fields defined on the centerlines of the rods.

We introduce a simplified model for the minimization of the elastic energy in thin shells. The thickness of the shell remains a parameter in this new model.

BACKGROUND: As an alternative to the cumbersome Kleihauer-Betke test (KBT), flow cytometry represents a powerful method for the identification and quantification of fetal red blood cells (RBCs) in maternal circulation. STUDY DESIGN AND METHODS: The aim of this study was to evaluate the Fetal Cell Count kit (IQ Products), an innovative flow cytometric method, based on the combination of antibodies directed, respectively, against fetal hemoglobin (HbF) and carbonic anhydrase (CA), a marker expressed after birth, to discriminate fetal RBCs from adult F cells containing HbF. The investigation was performed by two French laboratories that compared the data obtained by flow cytometry and KBT in 455 pregnant or just-delivered women as well as in 124 artificial mixtures containing from 0.01 to 5.00 percent cord cells. RESULTS: The FL1/FL2 histogram allowed distinction between fetal RBCs (HbF+, CA–), F cells (HbF+, CA+), and adult RBCs (HbF–, CA+). The limits of detection and quantification were determined at 0.03 and 0.10 percent or 0.02 and 0.05 percent when analyzing 100,000 or 200,000 events, respectively. Linearity was demonstrated between 0.01 and 5.00 percent fetal cells in the mixtures (r = 0.95, p

We consider a set of elastic rods periodically distributed over a 3d elastic plate (both of them with axis $x_3$) and we investigate the limit behavior of this problem as the periodicity $\varepsilon$ and the radius r of the rods tend to zero. We use a decomposition of the displacement field in the rods of the form u=U+v where the principal part U is a field which is piecewise constant with respect to the variable $(x_1,x_2)$ (and then naturally extended on a fixed domain), while the perturbation v remains defined on the domain containing the rods. We derive estimates of U and v in term of the total elastic energy. This allows to obtain a priori estimates on u without solving the delicate question of the dependence, with respect to $\varepsilon$ and r, of the constant in Korn’s inequality in a domain with such a rough boundary. To deal with the field v, we use a version of an unfolding operator which permits both to rescale all the rods and to work on the same fixed domain as for U to carry out the homogenization process. The above decomposition also helps in passing to the limit and to identify the limit junction conditions between the rods and the 3d plate.

In [4], the first two authors studied a nonlinear monotone problem in a multidomain composed of a part [Formula: see text], with a highly oscillating boundary, placed upon an asymptotically flat part of thickness hε. More precisely, [Formula: see text] is a "forest" of cylinders with fixed height and small cross section of size ε, distributed with ε-periodicity upon the flat domain. The analysis was achieved under the assumption εp/hε → 0 (p - 1 is the growth order of the operator at infinity), as ε tends to 0, and for rescaled external forces hε fε converging to 0 in the (rescaled) flat domain. In the present paper, we present the analysis under the assumption εp/hε → l, with l ∈ [0, +∞], and for general limit forces in the flat domain. When l ∈ ]0, +∞[, we show that a discontinuity in the Dirichlet transmission condition may occur between the limit domain filled by the oscillating boundary and the plate. This discontinuity is derived through solving a nonlinear problem (in general for a different monotone operator) in the unit cell of the oscillating boundary. When l = +∞, we show that a deterministic limit model may hardly be expected.

We consider a class of quasi-linear diffusion problems involving a matrix A(t,x,u) which blows up for a finite value m of the unknown u. Stationary and evolution equations are studied for L 1 data. We focus on the case where the solution u can reach the value m. For such problems we introduce a notion of renormalized solutions and we prove the existence of such solutions.

Methamphetamine and ecstasy are addictive drugs that cause major health problems in young people. Here we report on the development of high-affinity monoclonal antibodies to methamphetamine and its analogues, which may constitute powerful tools for antibody-based therapy. Six haptens, methamphetamine and ecstasy analogues, were synthesized, linked to a carrier protein and injected into mice. Several specific monoclonal antibodies were subsequently obtained following fusion of splenocytes from the immunized animals, with Sp2/O cells. Antibody specificity was fully investigated by competition ELISA, using a series of analogues, to identify specific amphetamine and/or ecstasy-specific antibodies. Antibody affinity was estimated to be in the range of 10(8) M(-1) with an enantiomeric hapten. Finally, two characteristic hybridoma clones (DAS-M243-6H5 and DAS-M278-4B12), secreting specific and potent mAbs were isolated. The development of drug-specific antibodies as in this study may provide promising therapeutic insight into how to neutralize methamphetamine in vivo during acute intoxication.

We prove existence and uniqueness of a solution for a class of quasi-linear problems with L 1 data. The diffusion matrix A ( x , u ) is allowed to degenerate with respect to the unknown u. We obtain uniqueness of the solution under a weak assumption on A ( x , u ) that permits to consider highly oscillating or/and increasing coefficients (with respect to u).

Cocaine abuse is a major health problem, with the number of overdose-related incidents on a constant increase. Monoclonal antibodies against cocaine and its major toxic metabolite cocaethylene, have been developed for immunotherapeutical neutralization in vivo. A series of monoclonal antibodies with high affinity for cocaethylene and cocaine were obtained. Clones DASm244-4D8A4A4 (4D8) and DASm244-5B3C3C6 (5B3) were selected and fully characterized. The antibodies secreted exhibited 1.40 x 10(8) and 3.69 x 10(7) M(-1) affinity constants for [3H]-cocaine and cocaethylene, respectively. In addition to cocaine, they bound to cocaethylene and did not recognize non-toxic cocaine metabolites. They did not bind to blood cells, indicating that they may be potential tools for cocaine neutralization in vivo in cases of overdose.

We consider a quasilinear equation (see (1.1)) with L1 data and with a diffusion matrix A(x,u), which is not uniformly coercive with respect to u (see Assumptions (H3)–(H4)). Under such assumptions it is not realistic, in general, to search for a solution which is finite almost everywhere. We introduce two equivalent notions of solutions which take into account the possible values +∞ and -∞ (see Definitions 2.1 and 2.3). Then we prove that there exists at least one such solution. At last we establish an uniqueness result in the class of simultaneous infinite valued solutions.

Catalytic antibodies with a metalloporphyrin cofactor or «hemoabzymes», used as models for hemoproteins like peroxidases and cytochrome P 450, represent a promising route to catalysts tailored for selective oxidation reactions. A brief overview of the literature shows that until now, the first strategy for obtaining such artificial hemoproteins has been to produce antiporphyrin antibodies, raised against various free-base, N-substituted Sn-, Pd- or Fe-porphyrins. Five of them exhibited, in the presence of the corresponding Fe-porphyrin cofactor, a significant peroxidase activity, with k cat / K m values of 3.7×10 3 –2.9×10 5 M −1 min −1 . This value remained, however, low when compared to that of peroxidases. This strategy has also led to a few models of cytochrome P 450. The best of them, raised against a water-soluble tin(IV) porphyrin containing an axial α-naphtoxy ligand, was reported to catalyze the stereoselective oxidation of aromatic sulfides by iodosyl benzene using a Ru(II)-porphyrin cofactor. The relatively low efficiency of the porphyrin–antibody complexes is probably due, at least in part, to the fact that no proximal ligand of Fe has been induced in those antibodies. We then proposed to use, as a hapten, microperoxidase 8 (MP8), a heme octapeptide in which the imidazole side chain of histidine 18 acts as a proximal ligand of the iron atom. This led to the production of seven antibodies recognizing MP8, the best of them, 3A3, binding it with an apparent binding constant of 10 −7 M. The corresponding 3A3–MP8 complex was found to have a good peroxidase activity characterized by a k cat / K m value of 2×10 6 M −1 min −1 , which constitutes the best one ever reported for an antibody–porphyrin complex. Active site topology studies suggest that the binding of MP8 occurs through interactions of its carboxylate substituents with amino acids of the antibody and that the protein brings a partial steric hindrance of the distal face of the heme of MP8. Consequently, the use of the 3A3–MP8 complexes for the selective oxidation of substrates, such as sulfides, alkanes and alkenes will be undertaken in the future.

We study a class of quasilinear elliptic problems with diffusion matrices that have at least one diagonal coefficient that blows up for a finite value of the unknown; the other coefficients being continuous with respect to the unknown (without any growth assumption). We introduce two equivalent notions of solutions for such problems and we prove an existence result in these frameworks. Under additional local assumptions on the coefficients, we also establish the uniqueness of the solution. In that case, and when the non-diagonal coefficients are bounded, this unique (generalized) solution is also the unique weak solution strictly less than the value where the diagonal coefficient blows up.

Background microRNAs (miRNAs) play crucial roles in major biological processes and their deregulations are often associated with human malignancies. As such, they represent appealing candidates as targets of innovative therapies. Another interesting aspect of their biology is that they are present in various biological fluids where, advantageously, they appear to be very stable. A plethora of studies have now reported their potential as biomarkers that can be used in diagnosis, prognosis and/or theranostic issues. However, the application of circulating miRNAs in clinical practices still requires the identification of highly efficient, robust and reproducible methods for their isolation from biological samples. In that context, we performed an independent cross-comparison of three commercially available RNA extraction kits for miRNAs isolation from human blood samples (Qiagen and Norgen kits as well as the new NucleoSpin miRNAs Plasma kit from Macherey-Nagel). miRNAs were further profiled using the Taqman Low Density Array technology. Results We found that, although these 3 kits had equal performances in extracting miRNAs from peripheral blood mononuclear cells, the Macherey-Nagel kit presented several advantages when isolating miRNAs from sera. Besides, our results have indicated that, depending on the quantity of the biological samples used, the extraction procedure directly impacted on the G/C composition of the miRNAs detected. Conclusion Overall, our study contributes to the definition of a reliable framework for profiling circulating miRNAs. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-395) contains supplementary material, which is available to authorized users.

Cell proliferation is controlled by cdk2 which in association with cyclin E and A regulates G1/S transition and S phase progression. cdk2 activation is dependent on its localization in the nucleus where regulatory mediators are found. We report that activation of cdk2 is associated with the formation of cdk2/MAP Kinase complexes. cdk2 associates with both inactive and activated MAP Kinase. Prevention of MAP Kinase activation by the MEK inhibitor PD98059 inhibits both activation and nuclear localization of cdk2 and S phase entry. These findings indicate that the nuclear translocation of cdk2 is associated with the formation of molecular complexes containing active MAP Kinase and is dependent on MAP Kinase activation. Oncogene (2000) 19, 4184 - 4189

Resume Nous donnons un resultat d'existence et d'unicite d'une solution renormalisee pour le probleme d'evolution ∂ u /∂ t − div( a(t,x,u ,Du) + Φ(u)) = ƒ - div g , ou le second membre appartient a L 1 ((0, T ) × Ω) + L p ′(0, T ; W −1 , p ′(Ω)) et ou l'operateur −div( a ( t,x,u , D u )) est un operateur de Leray-Lions qui croit comme ¦D u ¦ p − 1 en D u mais dont la croissance n'est pas controlee en u .

Manganese ions block apoptosis of phagocytes induced by various agents. The prevention of apoptosis was attributed to the activation of manganous superoxide dismutase (Mn-SOD) and to the antioxidant function of free Mn2+ cations. However, the effect of Mn2+ on B cell apoptosis is not documented. In this study, we investigated the effects of Mn2+ on the apoptotic process in human B cells. We observed that Mn2+ but not Mg2+ or Ca2+, inhibited cell growth and induced apoptosis of activated tonsilar B cells, Epstein Barr virus (EBV)-negative Burkitt's lymphoma cell lines (BL-CL) and EBV-transformed B cell lines (EBV-BCL). In the same conditions, no apoptosis was observed in U937, a monoblastic cell line. Induction of B cell apoptosis by Mn2+ was time- and dose-dependent. The cell permeable tripeptide inhibitor of ICE family cysteine proteases, zVAD-fmk, suppressed Mn2+-induced apoptosis. Furthermore, Mn2+ triggered the activation of interleukin-1beta converting enzyme (ICE/caspase 1), followed by the activation of CPP32/Yama/Apopain/caspase-3. In addition, poly-(ADP-ribose) polymerase (PARP), a cellular substrate for CPP32 protease was degraded to generate apoptotic fragments in Mn2+-treated B cell lines. The inhibitor, zVAD-fmk suppressed Mn2+-triggered CPP32 activation and PARP cleavage and apoptosis. These results indicate that the activation of caspase family proteases is required for the apoptotic process induced by Mn2+ treatment of B cells. While the caspase-1 inhibitor YVAD was unable to block apoptosis, the caspase-3 specific inhibitor DEVD-cmk, partially inhibited Mn2+-induced CPP32 activation, PARP cleavage and apoptosis of cells. Moreover, Bcl-2 overexpression in BL-CL effectively protected cells from apoptosis and cell death induced by manganese. This is the first report showing the involvement of Mn2+ in the regulation of B lymphocyte death presumably via a caspase-dependent process with a death-protective effect of Bcl-2.

A new method to quantify red blood cells (RBCs) containing fetal hemoglobin (HbF), or F cells, by flow cytometry was developed. The use of formaldehyde as fixative agent and sodium dodecyl sulfate (SDS) to permeabilize fixed RBCs resulted in a low staining background, a negligible Hb leakage, and minimal cell clumping. HbF was detected by immunofluorescence with a murine monoclonal antibody directed to the γ chain of human Hb. The accuracy of the F-cell count was evaluated on mixed-field populations of adult and cord RBCs. The results of flow cytometry were highly correlated with HbF dosage in the hemolysate by high-pressure liquid chromatography (HPLC) (R > 0.99). The sensitivity of the method allowed the study of HbF distribution at the single-cell level in normal controls and patients with sickle-cell disease (SCD). All patients exhibited a heterocellular distribution of HbF, with highly variable percentages of F cells and non-F cells. As an additional and valuable biological parameter in SCD, the mean HbF content per F cell could be deduced from the measurement of HbF level by HPLC and F-cell count by flow cytometry. Results were unchanged after storing the cells for several weeks in an optimized resuspending solution. Since it does not need uncommon reagents or devices and allows the simultaneous detection of membrane antigens by two-color flow cytometry, this method is convenient for routine laboratories as well as for research purposes. Cytometry 32:186–190, 1998. © 1998 Wiley-Liss, Inc.

An existence and uniqueness result of a renormalized solution for a class of doubly nonlinear evolution equations is established. The data belong to L 1 and no growth assumption is made on the nonlinearities. A comparison result is also proved for such solutions.

Resume Nous presentons deux cadres equivalents de solutions pour un probleme quasi-lineaire du type diffusion avec coefficients qui explosent pour une valeur finie de l'inconnue. Nous demontrons, sous l'hypothese de continuite des coefficients (sur leurs domaines de definition) par rapport a l'inconnue, un resultat d'existence d'une solution dans ces cadres equivalents. Sous des hypotheses plus fortes de regularite locale sur les coefficients, nous donnons un resultat d'unicite de cette solution, qui est aussi, dans ce cas, l'unique solution faible strictement plus petite que la valeur pour laquelle les coefficients explosent.

We prove two existence results of a solution for a nonlinear system in thermoviscoelasticity in which the mechanical dissipation is not linearized. The techniques of renormalized solutions for parabolic equations with L1 data are used to handle the energy conservation law.

Rather efficient catalysis of the decomposition of 5-nitro-benzisoxazole to the cyanophenol was observed with antibodies elicited against a cationic hapten structurally unrelated to the benzisoxazole substrate. The rate enhancement by the most active antibody is better than 104 and the reaction is catalyzed by a carboxylate group associated with a hydrophobic binding site.

Control of complement deposition on autologous cells is mediated by a group of complement regulatory membrane proteins acting at different levels of the complement cascade. Decay accelerating factor (CD55) prevents the assembly of C3 convertases and CD59 membrane inhibitor of reactive lysis (MIRL) restricts homologous complement lysis by the membrane attack complex of complement (MAC) by inhibition of C5b-8 catalyzed insertion of C9. The aim of this work was to study the eventual expression of CD55 and CD59 on human skeletal muscle fibers. Highly sensitive immunoblotting using murine monoclonal antibodies showed that CD59, but not CD55, was present in skeletal muscle fibers. Immunocytochemistry with a monoclonal antibody against CD59 demonstrated a dense granular immunostaining mainly localized at the level of the sarcolemma. Thus, CD59, but not CD55, is expressed on normal skeletal muscle fibers. CD59 may play a prominent role in preventing MAC deposition and subsequent complement-mediated damage in myopathies where the complement system activation is involved.

With the aim to obtain specific anti-cocaine antibodies directed against cocaine and active metabolites for use in immunotherapy, a series of six haptens were prepared, based on the structure of cocaine. The haptens differed by 3 positions of linkers: nitrogen, carboxyl group, and aromatic nucleus. The haptens were grafted onto 3 carrier proteins: bovine serum albumin, tetanus toxoid or keyhole limpet hemocyanin according to different methods of coupling: carbodiimide or mixed anhydride techniques. The immuno-conjugates were administered to rabbits and the antisera elicited were analyzed in term of titer, affinity and specificity. Variation in antisera properties were observed and attributed to the site of coupling the hapten, to the carrier proteins, and to the method of coupling. Antisera titers were in the range of 1/1 (no significant response) to 1/12,832, with antisera affinity up to 5.9 × 10(11) M-1. This strategy allowed the selection of a new hapten, which after coupling on carrier proteins, led to the production of antisera with a high specificity toward cocaine and cocaethylene, but exclude the inactive metabolites of cocaine.

International audience; This paper is devoted to describe the asymptotic behavior of a structure made by a thin plate and a thin rod in the framework of nonlinear elasticity. We scale the applied forces in such a way that the level of the total elastic energy leads to the Von-Kármán's equations (or the linear model for smaller forces) in the plate and to a one dimensional rod-model at the limit. The junction conditions include in particular the continuity of the bending in the plate and the stretching in the rod at the junction.

We analyze the asymptotic behavior of a junction problem between a plate and a perpendicular rod made of a nonlinear elastic material. The two parts of this multi-structure have small thicknesses of the same order $\delta$. We use the decomposition techniques obtained for the large deformations and the displacements in order to derive the limit energy as $\delta$ tends to $0$.

The epitope Fy6 recognized by two monoclonal antibodies (i3A and BG6), which inhibit binding of chemokines to the Duffy antigen, was characterized by means of peptides synthesized on pins (Epitope Scanning Kit) and deletion mutagenesis. Both antibodies showed very similar specificities. They recognized a linear epitope, the essential portion of which was the heptapeptide Gln-Leu-Asp-Phe-Glu-Asp-Val comprising amino acid residues 21-27, located between two glycosylation sites of the Duffy protein. All the amino acid residues of the epitope, except Glu, were essential for antibody binding, since they could not be replaced by any other amino acid residues or by only one or two. The Glu residue could be replaced by most other amino acid residues, and its replacement by 10 amino acid residues gave a distinct increase in the antibody binding. The results were in full agreement with the finding that the mutant of the Duffy antigen, lacking amino acid residues 23-25 (-Asp-Phe-Glu-), did not bind the i3A antibody, but bound the anti-Fy3 monoclonal antibody similarly to the wild type of the Duffy antigen. The apparent affinity constants of both anti-Fy6 antibodies were determined by surface plasmon resonance, using immunopurified Duffy protein as a ligand.

Recently, fibrinoid of the human placenta has been described as being composed of two main types differing in origin and chemical composition. Fibrin-type fibrinoid is mostly a blood clot product. Matrix-type fibrinoid was defined as the extracellular matrix secreted by extravillous trophoblast cells. The structure and composition of matrix-type fibrinoid was addressed in this study, focusing on fibronectins as one major constituent. A panel of antibodies directed against different fibronectin isoforms generated by different mRNA splicing, as well as antibodies recognizing oncofetal carbohydrate epitopes, were used on cryostat, paraffin and Lowicryl sections of placental tissue from different stages of pregnancy. The oncofetal carbohydrate epitopes studied comprised the blood group precursor antigens i and I. We identified the blood group-related antigen i as an additional marker for matrix-type fibrinoid. The antigen was detected on a glycoprotein that was also recognized by the fibronectin antibodies in western blots. Immunohistochemically this i-glycosylated oncofetal fibronectin-like molecule of about 55 kDa is expressed only by the invasive phenotype of extravillous trophoblast. Long chain carbohydrate moieties with a structure fulfilling the criteria for i reactivity on human placental fibronectin are known to have anti-adhesive properties and to enhance resistance of the protein chain to proteolysis. These properties underline the functional relevance of glycosylation of fibronectins in matrix-type fibrinoid and suggest matrix-type fibrinoid is a typical matrix of invasive cells. In contrast, the more mature blood group precursor I could be detected after sialidase pretreatment of sections. This antigen was expressed by villous, non-invasive trophoblast.

A 37-kDa protein was immunopurified from human erythrocytes as a complex with a monoclonal antibody directed against the Kell blood group protein of 93 kDa. A rabbit antibody raised against the purified complex reacted on a Western blot with the 93-kDa and 37-kDa proteins and was able to immunoprecipitate the 37-kDa component from K,, erythrocytes which express large amount of the Kx antigen, but not from erythrocytes of patients suffering from McLeod syndrome, a X-linked disorder in which the Kx antigen is lacking. Additional studies have shown that the 37-kDa protein is not glycosylated, and permitted the sequence of the 22 first N-terminal amino acids to be established. This sequence was identical to the predicted protein product of the XK gene cloned recently, which is deleted or mutated in McLeod patients [Ho, M., Chelly, J., Carter, N., Danek, A., Crocker, P. & Monaco, A. P. (1994) Cell 77, 869-8801. Our findings provide strong evidence that the 37-kDa red cell membrane protein is identical to the Kx protein produced by the XK structural gene and demonstrate that Kx and Kell proteins are two subunits expressed as a complex hold by disulfide bond(s) at the red cell surface.

This paper is devoted to describe the deformations and the elastic energy for structures made of straight rods of thickness 2δ when δ tends to 0. This analysis relies on the decomposition of the large deformation of a single rod introduced in Blanchard and Griso (Anal. Appl. 7(1):21–71, 2009) and on the extension of this technique to a multi-structure. We characterize the asymptotic behavior of the infimum of the total elastic energy as the minimum of a limit functional for an energy of order δ β (2

The binding of human natural antibodies to porcine endothelial cells is the first step leading to activation of complement and lysis of the cells. The kinetic of incorporation of propidium iodide into porcine endothelial cell line SVPAEC/6A or peripheral blood lymphocytes was investigated to monitor the permeabilization of target cells by membrane attack complex. In less than 5 min, more than 90% of porcine cells were highly fluorescent upon incubation with human sera, showing they incorporate propidium iodide. The lysis occurred neither with adult sera pretreated with dithiothreitol nor with umbilical cord sera, suggesting that lytic antibodies belong to the IgM class. By using antibodies purified from human sera, the bulk of lytic activity was found to be associated with IgM specific for the Galal-3Gal epitope, whereas IgG were not able to lyse the porcine cells. These antibodies could be readily absorbed on rabbit red blood cells known to express the main epitope target of xeno human antibodies. Finally, our results show that permeabilization of porcine endothelial cells is a very early phenomenon, probably directly associated with the biological process responsible for the hyperacute rejection.

This paper deals with the introduction of a decomposition of the deformations of curved thin beams, with section of order δ, which takes into account the specific geometry of such beams. A deformation v is split into an elementary deformation and a warping. The elementary deformation is the analog of a Bernoulli–Navier's displacement for linearized deformations replacing the infinitesimal rotation by a rotation in SO(3) in each cross section of the rod. Each part of the decomposition is estimated with respect to the L2norm of the distance from gradient v to SO(3). This result relies on revisiting the rigidity theorem of Friesecke–James–Müller in which we estimate the constant for a bounded open set star-shaped with respect to a ball. Then we use the decomposition of the deformations to derive a few types of asymptotic geometrical behavior: large deformations of extensional type, inextensional deformations and linearized deformations. To illustrate the use of our decomposition in nonlinear elasticity, we consider a St Venant–Kirchhoff material and upon various scalings on the applied forces we obtain the Γ-limit of the rescaled elastic energy. We first analyze the case of bending forces of order δ2which leads to a nonlinear extensible model. Smaller pure bending forces give the classical linearized model. A coupled extentional-bending model is obtained for a class of forces of order δ2in traction and of order δ3in bending.

Resume L'alloimmunisation anti-HPA-1a chez les femmes HPA-1b homozygotes est fortement associee au phenotype HLA-DR3, DRw52a, ce qui suggere que les molecules HLA de classe II jouent un role crucial dans la reponse immune contre l'antigene HPA-1a. Le systeme diallelique HPA-1 est porte par la glycoproteine IIIa et resulte d'un polymorphisme unique de l'acide amine 33. Un mecanisme de presentation de l'antigene HPA-1a par ces molecules de classe II peut etre envisage. Nous avons donc teste la liaison « in vitro , par une technique sur plaque et en solution, de peptides de synthese couvrant la region 25–42 de la GPIIIa a des molecules HLA-DR3 et DRw52a purifiees. Aucune liaison n'a ete observee, indiquant que la region cruciale pour la liaison aux molecules HLA de classe II n'est pas la region 25–42 de la GPIIIa ou que d'autres phenomenes sont requis « in vivopour la liaison. Ces resultats peuvent aussi suggerer un role indirect de l'acide amine 33 conduisant a la stimulation des cellules T.

Resume Des anticorps monoclonaux diriges contre les glycoproteines membranaires DAF (antigene CD55) et MIRL (HRF20 ou antigene CD59) ont ete utilises pour identifier les populations erythrocytaires CD55− et CD59− des patients atteints d'hemoglobinurie nocturne paroxystique (HNP). Les anticorps NaM16-4D3 (CD55, IgG2a) et NaM77-1E5 (CD59, IgG3) sont faiblement agglutinants et representent des outils de choix pour la quantification par cytometrie en flux indirecte des populations erythrocytaires normales (HNPI) et anormales (HNPII et HNPIII) des patients HNP. Les anticorps NaM125-7H10 (CD55) et NaM123-6G12 (CD59), de classe IgM ont ete selectionnes pour leur pouvoir agglutinant et permettent de separer les cellules HNPI des cellules HNPII et HNPIII par la technique d'agglutination en gel. Une relation directe a ete etablie entre les erythrocytes fluorescents (cytometrie en flux) et les erythrocytes agglutines (agglutination en gel) pour des populations DAF+ et DAF− artificielles et pour une serie de patients HNP connus. Ces methodes utilisant des anticorps monoclonaux specifiques representent une alternative aux methodes classiques d'hemolyse. Sur la base de l'analyse de plus de 100 echantillons dont 12 cas de HNP, nous proposons : 1) la caracterisation rapide des erythrocytes CD55− et CD59− par agglutination en gel a l'aide des anticorps de classe IgM ; 2) la quantification des populations erythrocytaires normales et anormales par cytometrie en flux.

International audience; We introduce a simplified model for the minimization of the elastic energy in thin shells. This model is not obtained by an asymptotic analysis. The nonlinear simplified model admits always minimizers by contrast with the original one. We show the relevance of our approach by proving that the rescaled minimum of the simplified model and the rescaled infimum of the full model have the same limit as the thickness tends to 0. The simplified energy can be expressed as a functional acting over fields defined on the mid-surface of the shell and where the thickness remains as a parameter.

Resume Dans les thrombopenies neonatales allo-immunes, le systeme PI A est le plus frequemment implique. Cependant, dans environ 30% des cas, aucun anticorps circulant anti-PI A1 ne peut etre decele dans le serum maternel malgre les diverses techniques utilisees. Nous proposons d'ameliorer la detection sur membrane de nitrocellulose par l'utilisation de peptides provenant d'extraits triton X-114 de plaquettes traitees a l'α-chymotrypsine. La lyse par ce detergent non-ionique permet un enrichissement en peptides hydrophobes issus de la glycoproteine IIIa (GPIIIa) portant la specificite antigenique PI A1 . Sur les repliques obtenues apres transfert electrophoretique, les anti-PI A1 reconnaissent deux peptides caracteristiques de masse moleculaire 66 et 54 kDA qui portent l'epitope PI A1 . Cette technique, utilisee pour le depistage et l'identification des anticorps anti-PI A1 se revele etre sensible, fiable et realisable dans un temps relativement court (minimum de 6 h).

We investigate the behavior of the deformations of a thin shell, whose thickness $\delta$ tends to zero, through a decomposition technique of these deformations. The terms of the decomposition of a deformation $v$ are estimated in terms of the $L^2$-norm of the distance from $\nabla v$ to $SO(3)$. This permits in particular to derive accurate nonlinear Korn's inequalities for shells (or plates). Then we use this decomposition technique and estimates to give the asymptotic behavior of the Green-St Venant's strain tensor when the {\it ''strain energy''} is of order less than $\delta^{3/2}$.