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Papers by François Hentges

Journal of Immunology, Mar 15, 2000

The gene of the leukocyte-specific transcript (LST1) is encoded within the TNF region of the huma... more The gene of the leukocyte-specific transcript (LST1) is encoded within the TNF region of the human MHC. The LST1 gene is constitutively expressed in leukocytes and dendritic cells, and it is characterized by extensive alternative splicing. We identified 7 different LST1 splice variants in PBMC; thus, 14 LST1 splice variants (LST1/A-LST1/N) have been detected in various cell types. These isoforms code for transmembrane as well as soluble LST1 proteins characterized by two alternative open reading frames at their 3 end. We demonstrate the presence of the transmembrane variant LST1/C on the cell surface of the monocytic cell lines U937 and THP1. Recombinant expression of LST1/C permitted its profound inhibitory effect on lymphocyte proliferation to be observed. In contrast, the alternative transmembrane variant LST1/A, the extracellular domain of which shows no amino acid sequence homology to LST1/C exerted a weaker but similar inhibitory effect on PBMC. These data demonstrate the protein expression of LST1 on the cell surface of mononuclear cells, and they show an inhibitory effect on lymphocyte proliferation of two LST1 proteins although they have only a very short amino acid homology.

Revue Francaise D Allergologie, Apr 1, 2014

Arthritis & Rheumatism, Mar 27, 2012

Internal Medicine Journal, Mar 1, 2007

F1000Research, Dec 13, 2010

BACKGROUND Natural killer (NK) cells are lymphocytes of the innate immune system that serve as a ... more BACKGROUND Natural killer (NK) cells are lymphocytes of the innate immune system that serve as a first line of defense against tumors and viruses. Their function is controlled by a dynamic balance between activating messages transmitted by their activating receptors (AR) and inhibitory signals transmitted by their inhibitory receptors (IR, such as the KIR family in humans and the Ly49 family in mice). NK cells acquire functional competence through "licensing" by self-MHC class I molecules; they have to express a self-specific IR in order to become activated. NK cells that do not express such a receptor are hyporesponsive.

Journal of Investigational Allergology and Clinical Immunology, 2021

Background: Immediate and delayed-type hypersensitivity reactions to pet-borne allergens are comm... more Background: Immediate and delayed-type hypersensitivity reactions to pet-borne allergens are common in atopic diseases. In atopic dermatitis (AD), controversy surrounds the contribution to the disease of cross-reactivity to self-proteins. Human cystatin A and the cat allergen Fel d 3 belong to the cystatins, an evolutionary conserved protein family. The objective of the present study was to assess crossreactivity between mammalian cystatins and to analyze T-cell responses to cystatin in AD patients sensitized to pet dander. Methods: cDNA coding for dog cystatin was cloned from dog skin. Sera from 245 patients with IgE-mediated sensitization to cat and dog dander were tested for IgE binding to recombinantly expressed feline, canine, and human cystatin. Of these, 141 were also diagnosed with AD. Results: Cystatin-specific IgE was detected in 36 patients (14.7%), of whom 19 were considerably affected by AD. Within the AD patients, 9 had measurable IgE against all 3 cystatins. Cystatin-...

Revue Française d'Allergologie, 2017

Disponible en ligne sur ScienceDirect www.sciencedirect.com Revue française d'allergologie xxx (2... more Disponible en ligne sur ScienceDirect www.sciencedirect.com Revue française d'allergologie xxx (2017) xxx-xxx Le syndrome poisson-poulet : une nouvelle allergie croisée Fish-chicken syndrome: A new form of clinical cross-reactivity

Allergologie select, 2017

Protein-and DNA-based assays as complementary tools for fish allergen detection Background: Fish ... more Protein-and DNA-based assays as complementary tools for fish allergen detection Background: Fish is one of the most important, allergenic foods worldwide. Parvalbumin is the well characterized, major allergen in fish muscle. In this study, we developed a protein-and a DNA-based method for the sensitive detection and authentication of eight commonly consumed fishes in food and compared their applicability. Methods: Fish parvalbumins were purified. Polyclonal, anti-parvalbumin antibodies were raised in rabbits and mice. Protein extracts from food were analyzed by quantitative ELISA. Parvalbumin genes were cloned and sequenced for the design of parvalbumin gene-specific PCR-primers. DNA extracted from food was subjected to specific PCR. Results: Increasing parvalbumin contents were quantified by ELISA in fresh fish, in the order of tuna < mackerel < cod < salmon/trout < redfish < carp < herring. The parvalbumin content of processed fish was up to 67% lower than in fresh fish. In spiked food samples, 1 to 15 ppm fresh fish and 30 to 170 ppm processed fish were still detectable by ELISA. The eight fishes were identified by specific PCR using 0.2 to 10 ng fish DNA. PCRs detected still 3 ppm fresh fish and 30 to 150 ppm processed fish in spiked samples. Conclusions: Both the protein-and the DNA-based method have sufficient sensitivity to protect fish-allergic consumers. The ELISA allows allergen quantification, while the PCR identifies the fish present in the food. The detection limits of both methods vary depending on different factors. Both methods need to be carefully validated for each fish and fish product when used in detection assays.

Clinical and Translational Allergy, 2016

Background: Delayed food anaphylaxis upon consumption of red meat is attributed to specific IgE-a... more Background: Delayed food anaphylaxis upon consumption of red meat is attributed to specific IgE-antibodies directed to galactose-α-1,3-galactose (α-Gal). Anaphylactic reactions may occur after ingestion of meat from different mammals, mainly beef and pork, but reactions to lamb, rabbit or horse have also been reported. In particular, pork kidney has been shown to trigger symptoms that were more severe and occurred within a shorter delay. The objective of the present study was the identification and characterization of pork kidney proteins carrying α-Gal carbohydrates and mediating delayed allergic reactions through specific IgE to α-Gal. Materials and methods: A cohort of 59 patients with specific IgE to α-Gal was screened by immunoblot for IgE-reactive proteins in pork kidney extract. Proteins were purified by affinity chromatography and identified by Edman sequencing and peptide mass fingerprinting. Isolated proteins were used in immunoassays using patient sera and α-Gal specific antibodies. Allergenicity was assayed in basophil activation and skin prick test. Results: Multiple IgE-binding proteins were detected in protein extracts of pork kidney by immunoblot using patient sera and an anti-α-Gal antibody. Reactive bands were located in the high molecular weight range of 100 to ≥200 kDa. Two major IgE-binding proteins were identified as porcine angiotensin I converting enzyme (ACE I) and aminopeptidase N (AP-N). IgE-binding to both proteins was lost by periodate treatment, resulting in oxidation of carbohydrates. Addition of α-Gal inhibited IgE-reactivity to both peptidases. Allergenicity was confirmed by activation of patient basophils and positive skin prick tests. Conclusions: Two IgE-reactive cell membrane peptidases carrying α-Gal epitopes were identified in pork kidney, a tissue which is known as potent inducer of red meat-induced anaphylaxis. Allergenicity and clinical relevance of these proteins were confirmed in patients with delayed anaphylaxis to red meat by skin prick test and basophil activation.

Journal of investigational allergology & clinical immunology, 2012

Allergy, Feb 1, 1997

After observing a patient allergic to cat dander and pork but devoid of other allergies, we prosp... more After observing a patient allergic to cat dander and pork but devoid of other allergies, we prospectively screened patients known to be allergic to cat for a second sensitization to pork. After collecting the sera of 10 young patients found to contain specific IgE to cat dander and pork, we undertook this study to detect the possible cross-reactive allergen, define its molecular characteristics, and evaluate its clinical relevance. Through immunoblotting techniques, cat and porcine serum albumin were found to be jointly recognized molecules. These findings were further analyzed by specific anti-albumin IgE titrations and cross-inhibition experiments. Cat serum albumin cDNA was obtained from cat liver, and the corresponding amino acid sequence was deduced and compared to the known porcine and human serum albumin sequences. Inhibition experiments showed that the spectrum of IgE reactivity to cat serum albumin completely contained IgE reactivity to porcine serum albumin, suggesting that sensitization to cat was the primary event. In two cohorts of cat-allergic persons, the frequency of sensitization to cat serum albumin was found to lie between 14% and 23%. Sensitization to porcine albumin was found to lie between 3% and 10%. About 1/3 of these persons are likely to experience allergic symptoms in relation to pork consumption. Sensitization to cat serum albumin should be considered a useful marker of possible cross-sensitization not only to porcine serum albumin but also to other mammalian serum albumins.

Allergologie, Jul 1, 2012

The Journal of Allergy and Clinical Immunology, 2009

The Journal of Allergy and Clinical Immunology, Mar 1, 2005

Anaphylactic reactions caused by bites of the European pigeon tick Argas reflexus are repeatedly ... more Anaphylactic reactions caused by bites of the European pigeon tick Argas reflexus are repeatedly reported. This soft-backed tick is a parasite of wild pigeons colonizing urban buildings and houses. Occasionally the ticks can bite human beings, inducing anaphylactic reactions in sensitized patients. Our aim was to characterize the major allergen implicated in a series of anaphylactic reactions caused by Argas bites and to produce the allergen as recombinant protein for diagnostic purposes. Protein extracts were prepared from whole A reflexus bodies, and IgE immunoblots were performed with sera from 13 patients who had an anaphylactic reaction with pigeon tick bites. A cDNA expression library was constructed from whole ticks and screened with a polyclonal rabbit antiserum raised against the major allergen. The cDNA coding for the dominant allergen Arg r 1 could be isolated. It encodes a protein belonging to the lipocalin family. Allergenicity of the recombinant Arg r 1 was confirmed by immunoblot, ELISA, and intradermal skin tests. The dominant allergen of A reflexus has been isolated and the corresponding cDNA cloned. The recombinant protein, a lipocalin, was expressed in Escherichia coli and was shown to be immunoreactive in vitro and in vivo. Recombinant Arg r 1 was used as a diagnostic tool in a series of anaphylactic reactions caused by pigeon tick bites.

Background: Der p 3 a trypsin-like protease is a Dermatophagoides pteronyssinus allergen which is... more Background: Der p 3 a trypsin-like protease is a Dermatophagoides pteronyssinus allergen which is synthesized in the mite under a zymogen form. The enzymatic activity of this allergen has been shown to enhance the inflammatory process of allergy. To date, there are a few studies that described the allergenicity and the IgE reactivity of the group 3 allergens, the allergenic properties of recombinant Der p 3 was also not characterized. Methods: The autolysis of rDer p 3 and rDer p 3 S196A were analyzed by means of SDS-PAGE and enzymatic activity and their allergenicities by means of assays for IgE binding, IgE binding inhibition and basophiles mediator-release. Results: 100% of the sera from allergic patients showed IgE reactivity to natural Der p 3 and recombinant form. However, the IgE binding to the Der p 3 was less 4 times than rDer p 1. The IgE binding to rDer p 3 S196A was higher than rDer p 3. These variations can be linked with the phenomen of autolysis and instability of Der p 3 during the ELISA test. The mediators release performed with RBL sensitized with sera from allergic patients and stimulated with rDer p3, rDer p 3 S196A and natural Der p 3 were similar and lower than Der p 1 for concentration < 10 ng/ml. Conclusions: recombinant mature Der p 3 retained overall identity to its natural form in terms of structure and allergenicity. The instability and autolysis of Der p 3 drastically influence its IgE binding capacity. These results can be explain the considerable variations with the frequencies reactivity (16-100%) of natural Der p 3. The RBL assays demonstrated that the allergenicity of rDer p 3 is similar to rDer p 1 for the concentrations >10 ng /ml.Peer reviewe

Leukemia, Aug 4, 2005

of females showing clonal myelopoiesis on XCIP analysis (26/60) actually had wild-type JAK2 is of... more of females showing clonal myelopoiesis on XCIP analysis (26/60) actually had wild-type JAK2 is of particular interest, since it reinforces the view that mutations other than JAK2 V617F are potentially implicated in the pathogenesis of ET (Table 2). In summary, our data on a large population of subjects with a diagnosis of ET confirm recent observations that around half of them have the JAK2 V617F mutation in granulocytes; however, the presence of the mutation does not appear to correlate with specific clinical-laboratory characteristics, so that, apart from the diagnostic power, its role in the clinical management of patients remains to be ascertained.