AB0158 IMPACT OF JAK INHIBITORS ON MACROPHAGE POLARISATION: PERSPECTIVES FOR SYSTEMIC SCLEROSIS

Background:

Macrophage can adopt various phenotypes and activation states according to their surrounding microenvironment. M1 or inflammatory macrophages are generated under IFNɣ/LPS signaling and express the membrane marker CD86. Different subtypes of M2 macrophages are also described: M2a macrophages (generated under IL4/IL13 signaling) and characterized by a high expression of CD206 and pro-fibrotic properties and, M2c macrophages (generated under IL10 and/or glucorticoid signaling), considered as anti-inflammatory resolving macrophages. There is growing interest in the role of macrophages in the pathogenesis of Systemic Sclerosis (SSc). Recent studies highlight that macrophages from fibrotic tissues such as lung or skin from SSc patients have a M2 phenotype whereas, in blood-monocytes derived macrophages (MDM), SSc MDM have a mixed signature associating M1 and M2 characteristics. Jak inhibitors are treatments used in rheumatoid arthritis and that can variously target signals that could be involved both in M1 and in M2 polarisation.

Objectives:

This study evaluates the impact of three Jak inhibitors on the polarisation state of human MDM in vitro.

Methods:

Blood monocytes form healthy donors (HD) were differentiated with M-CSF (for 7 days) in MDM and pre-treated by ruxolitinib (Jak2-Jak1 inhibitor), tofacitinib (Jak3 inhibitor) or itacitinib (Jak1 inhibitor) (1µM for all). They were then polarised into M1i (IFNɣ, 20µg/mL), M1Li (IFNɣ+LPS, 20µg/mL), M2a (IL4+IL13; 20µg/ML), M2c (IL10, 20µg/mL) and M2c(dex) (IL10+dexamethasone, 10 nM). The impact of each Jak inhibitor on phenotype (flow cytometry), gene expression (qPCR) and cytokine secretion (ELISA) was evaluated in each polarisation state.

Results:

Concerning phenotypes, all Jak inhibitors reduced the expression of the M1i and M1Li marker CD86, but ruxolitinib had a higher effect. Only ruxolitinib reduced the expression of the M1i marker MHCII. All Jak inhibitors reduced the expression of CD206 in M2a. They had no impact on the expression of CD163, CD204 in any M2 conditions. Key M1 genes were repressed by all Jak inhibitors, such as CXCL10, IL6 or TNFα with a more significant effect of ruxolitinib. All Jak inhibitors reduced the gene expression of CXCL13 and SOCS3 in M2c. Secretion levels of IL6 and CCL18 were also repressed, with a more significant effect of ruxolitinib.

Conclusion:

Jak inhibitors can limit M1 and M2 polarisation state in vitro, with a more significant effect of the Jak2-Jak1 inhibitor ruxolitinib. The relevance of these results in MDM from SSc patients and in vivo models of SSc is still to be determined.

Disclosure of Interests:

Alain LESCOAT: None declared, Alice Ballerie: None declared, Marie Lelong: None declared, Claudie Morzadec: None declared, Stéphane Jouneau Grant/research support from: AIRB, Boehringer Ingelheim, LVL Medical, Novartis, Roche, Bellorophon Therapeutics, Biogen, Fibrogen, Galecto Biotech, Gilead Sciences, Pharm-Olam, Pliant Therapeutics, Savara Pharmaceuticals/Serendex Pharmaceuticals, Consultant of: Actelion, AIRB, AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Chiesi, Genzyme, GlazoSmithKline, LVL Medical, Mundipharma, Novartis, Pfizer, Roche, Sanofi, Patrick Jégo: None declared, Laurent Vernhet: None declared, Olivier Fardel: None declared, Valérie Lecureur: None declared

The importance of EN ISO 15189 accreditation of allergen-specific IgE determination for reliable in vitro allergy diagnosis

BACKGROUND

Allergen-specific serum immunoglobulin E detection and quantification have become an important step in allergy diagnosis and follow-up. In line with the current trend of laboratory test accreditation to international standards, we set out to design and assess an accreditation procedure for allergen-specific serum IgE.

METHODS

Method validation according to the accreditation procedure under the EN ISO 15189 standard was carried out for allergen-specific immunoglobulin E determination using the fluoroimmunoenzymatic method ImmunoCAP(®) (ThermoFisher). Data were produced by 25 hospital laboratories in France. A total of 29 allergen specificities including mixes, extracts, and molecular allergens were assayed. Allergen-specific serum immunoglobulin E concentrations ranged from 0.1 to 100 kUA /l.

RESULTS

Repeatability, reproducibility, and accuracy results fulfilled method validation criteria for automated laboratory tests and proved similar irrespective of the allergen specificity, allergen-specific serum immunoglobulin E concentration, or individual laboratory.

CONCLUSION

Allergen-specific serum immunoglobulin E determination with the fluoroimmunoenzymatic method ImmunoCAP(®) is a highly repeatable, reproducible, and accurate method which may be considered as a single analyte assay in view of the EN ISO 15189 accreditation procedure.

Similar lipid profile but improved long-term outcomes with sirolimus after cyclosporine withdrawal compared to sirolimus with continuous cyclosporine

Renal transplant recipients show an increased risk of cardiovascular disease compared with a nontransplant population. Herein we have shown an analysis of a randomized controlled trial wherein 525 patients receiving a first or second (9.7%) renal allograft from a deceased (89.1%), a living-related (7.8%), or a living-unrelated donor (3.1%) received sirolimus (SRL), cyclosporine (CsA), and steroids (ST) at the time of transplantation with randomization at 3 months after transplantation of 430 eligible patients to continue on SRL-CsA-ST or to have CsA withdrawn with increased SRL trough targets (SRL-ST group). Graft survival, patient survival, and renal function at 5 years were analyzed by average fasting total cholesterol (<or=200 or >200 mg/dL) and triglyceride (<or=240 or >240 mg/dL) subgroups. At 5 years, total, high-density lipoprotein (HDL), and low-density lipoprotein [LDL] cholesterol and triglyceride values were similar between the groups. Statins ( approximately 80% of patients of both groups) were most effective to lower cholesterol ( approximately 50 mg/dL; P < .001; both groups), and fibrates ( approximately 25% of patients of both groups) were most effective to decrease triglycerides ( approximately 100 mg/dL; P < .001; both groups). Renal function and blood pressure were significantly better with SRL-ST. Hypercholesterolemia and hypertriglyceridemia were associated with reduced graft survival, patient survival, and calculated GFR, but the only significant difference was lower graft survival among SRL-CsA-ST patients with hypertriglyceridemia. Cardiovascular-related deaths were reported in 3.7% and 2.8% of patients in the SRL-CsA-ST and SRL-ST groups, respectively. In conclusion, when compared with continuous SRL-CsA-ST, CsA withdrawal at 3 months followed by SRL-ST significantly improved glomerular filtration rate (GFR) and blood pressure without a further increase in lipid parameters or an incidence of untoward effects from hyperlipidemia, despite a 2-fold higher SRL exposure.

Immunochemical comparison of the allergenic potency of spores and mycelium of Cladosporium cladosporioides extracts by a nitrocellulose electroblotting technique

BACKGROUND

The lack of well standardized or characterized extracts that contain the relevant allergens of the appropriate fungus is resulting in a high heterogeneity of the commercial preparation.

MATERIAL AND METHODS

Immunochemical detection of the allergens composition of spore and mycelium of C. cladosporioides was studied by electroblotting using sera from Cladosporium allergic patients and 125 I- anti- human IgE. A MW range of allergens between 16 to 88 KDa was identified. The most important with a MW of 16, 20,30, 39, 43, 50, 60 and 88 KDa.

RESULTS

The allergenic composition of spore and mycelium looked very similar. However, partial or total inhibition of the serum with a conidial or mycelial extract demonstrated that the total concentration of allergens (particulary 20 and 60 KDa molecules) was higher in the conidium than in the mycelium.

CONCLUSIONS

These results indicated that conidium and mycelium contained the same allergenic determinants but at different concentration in the two propagule. Results with 50 % inhibited sera demonstrated also that the total concentration of allergens was higher in the conidium than in the mycelium.

Comparison of the allergenic potency of spores and mycelium of Cladosporium

The allergenic potency of spore and mycelium extracts of Cladosporium was estimated by RAST, RAST inhibition and PCA tests. Spores contained a concentration of allergens higher than mycelia. Results of PCA tests suggested that spores contained specific allergens. However, in a comparative study of extracts from different species of Cladosporium animal and human models gave different estimates of the allergenic potency of the different species. In spite of these variations it was shown that extracts from spores of Cladosporium contained the highest amount of Cladosporium allergens.

[Neonatal screening of glucose-6-phosphate dehydrogenase deficiency in umbilical cord blood]

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most frequent enzyme deficiency. It is a sex-linked genetic disease concerning mostly african, mediterranean and far-eastern populations. The main clinical expression is a hemolytic anemia which can be acute or chronic. During the neonatal period the disease may manifest as neonatal jaundice. We have been asked by the neonate department to set up a blood screening test for this deficiency. We have therefore developed a test using umbilical cord blood. The assay of G6PD has been automatised and red blood cell aspartate-amino-transferase (ASAT) chosen as a reference enzyme to evaluate the age of red blood cells. Normal values of G6PD, ASAT and G6PD/ASAT ratio have been calculated from 235 cord samples. Genetic frequency of this deficiency in 2002 was 6% in male and 1% in female newborns.

[Does the allergic child become sensitized to small domestic mammals (guinea pig, hamster, rabbit?)]

Our own works show among allergic children a frequency of sensitization of 30% to cats and of 17% to dogs. But, the proportion of sensitizations to other small domestic mammals such as guinea pigs, hamsters of rabbits seems to be unknown. Among atopic children with a known contact with those pets we noted: for guinea pig: 29% positive cutaneous or RAST tests 21% clinical signs in presence of animals; for hamster respectively 28% and 6.5%; for rabbit respectively 18% and 12.3%. Guinea pigs seem to be more sensitizing animals, followed by rabbits, then by hamsters. As for cats and dogs, eviction is imperative when a sensitization is demonstrated.

[Is it necessary to test children having summer respiratory problems with cereal pollens?]

We tested 100 children with clinical signs that occurred in spring or summer. Prick tests were made with extracts of wild grass pollens (Dactylis, Phleum, Lolium) and with separate cereal pollens (Wheat, oats, Sweet-corn Barley and Rye). In 20 children whose test was negative for wild grass pollen, we saw no sensitization to cereals. In 80 children with grass pollenosis, Barley and Rye are the cereals that gave the most positive prick tests, whilst sweet corn is the cereal with most negative tests.

[Is immediate allergy the source of hematuria in children]

The authors report 2 cases of children presenting with episodes of hematuria, frequently following attacks of asthma or of allergic rhinitis. In both children, a respiratory provocation test with a mite extract triggered off hematuria. One child had an IgA nephropathy. In the second, the renal biopsy was normal and the cause of the hematuria remains unknown. These case reports suggest the need to carry out a systematic search for microscopic hematuria in patients with asthma.

[Chronic rhinopathies of childhood (apropos of 265 cases)]

We observed among 265 children with a chronic rhinopathy: 187 allergic rhinopathies, associating sneezing, rhinorrhea and nasal eosinophilia, particularly caused by a sensitization for mites. 10 non allergic eosinophilic rhinopathies with identical clinical signs, and major nasal eosinophilia without any allergic factor. 68 non allergic non eosinophilic rhinopathies, where are preponderant nasal obstruction, olfaction troubles, ORL infections (otitis and sinusitis). Their etiology is probably various: psychic factors, ciliary dyskinesias, vasomotor phenomena...

[Comparative study of 3 positive controls for routine prick tests in children: 48/80, 1 mg histamine and 5 mg histamine]

We compared, among 153 children 2 to 14 years old, responses to some positive control solutions for prick tests made with a Stallerpoint. We obtained the following values: -6% - 48/80:4.46 +/- 1.88 mm -1 mg/ml Histamine:3.49 +/- 1.67 mm -5 mg/ml Histamine:5.13 +/- 1.78 mm. 1 mg/ml histamine gives too many null responses (12/153) to represent a valuable positive control. 5 mg/ml histamine, on the other hand, gives some very strong reactions which may induce an underestimation of responses to allergen tests. Compound 48/80 seems to remain the best positive control for prick test exploration of immediate allergy in children. An alternative might be an intermediate solution of histamine 2.5 mg/ml.

[Are there milder forms of the syndrome called hyper-IgE? Diagnostic problems. Apropos of 2 cases]

We present the observations of two boys eight and four years old whose the only clinical sign is a chronic otorrhea. We found many of usual features of the hyper IgE syndrome: raised total IgE (4000 to 8000 Ul/ml) and hypereosinophilia (1100 to 3800/mm3). We found a lowered proportion of CD8+ cells (suppressive or cytotoxic): 16 and 18% (normal values: 26 +/- 5%). The chemotaxis of polymorphonuclears is also lowered: 9.2 to 6.0 cells by microscopic field with FMLP presence (normal values 40 to 50). These two observations are compared with other literature cases where clinical picture is moderate, but biological signs very suggestive.

[Long-term tolerance of specific hyposensitization with the aid of calcium phosphate-adsorbed mite extracts]

90 children receive a specific hyposensitization with calcium phosphate adjuvant purified Dermatophagoides pteronyssinus allergens. We note 44% very good results, 37% good results and 19% failures. We propose to begin with 1/1,000,000 concentration every other day until 1/10,000 concentration is obtained under antihistamine protection. Tolerance is satisfactory: moderate respiratory reaction are pointed out for 22 patients. No anaphylactic shock is encountered. For 80 children with more than three years recall, we totalled 3,700 injections for 340 watching years. Only eight patients are sight lost. 1/10,000 concentration is obtained in 72/80 followed up children.

[Comparison of specific IgE levels versus various milk proteins in 76 eczematous children]

Among 76 eczematous children, we realized a RAST test for whole milk and milk specific proteins: lactalbumin, lactoglobulin and casein. One of these RAST tests, at least, was positive for 27 children. Whole milk RAST test is the most frequently positive (77%) but some non specific reactions seem to interfere: only three children are clinically milk sensitive. Among specific proteins, lactalbumin is more frequently positive (59%) than lactoglobulin (51%) and casein (18%). Eczematous children with positive milk RAST tests, if compared to other eczematous children, have currently more mite allergies and positive egg RAST tests. They have a tendency (non significative) to be more frequently breast fed. The positivity of milk RAST tests seems to belong to a polysensitization and infrequently concerns a clinical allergy.

[Severe local reactions to mosquito bites. Apropos of 20 cases]

We relate 21 observations of children who present major local reactions, immediate and delayed after mosquito bites. An associated reagin mechanism is obvious in 8 patients: five positive cutaneous or RAST tests and three a basophil degranulation tests. They are mostly young children (14/21 an less 5 years old). After some difficult years, the evolution is finally favourable with a specific hyposensitization or under antihistaminic protection (ketotifen) during summer.

[What problems does childhood toxocariasis currently pose? Apropos of 6 clinical cases]

About six observations of toxocariasis (visceral larva migrans syndrome). We relate six observations of toxocariasis among children. In one case, an ocular localization is probable. For other five patients, they are inapparent forms. The allergologist pediatrician may be consulted because of a major hypereosinophilia (greater than 10,000/mm3) and an elevation of total IgE (greater than 2,000 UI/ml). Allergic and current parasitologic assays are negative and diagnostic key is given by toxocara serology. We insist on interest and reliability of passive hemagglutination test with a purified antigen (titer greater than or equal to 1/320). Treatment now is preferably flubendazole (50 mg/kg/day for six days) eventually renewed.

[Can Acarus siro be considered an allergenic mite in children? Evaluation of 248 cases]

Among 248 allergic children we noted 44 children (21%) with strongly or moderately positive cutaneous tests (In seven out of these tested children respiratory provocation tests are very positive). They are urban children and their houses are not different from other allergic children. They are mostly boys (72%), more than 5 years old (91%), with an asthma (84%), a radiological sinusitis (45%), an hypereosinophilia (88%) and elevated total IgE (90%). 43/44 children also have positive cutaneous tests to Dermatophagoides pteronyssinus mite. Since respiratory sensitivity is exquisite, we undertook a specific hyposensitization for some patients with encouraging results.

[Are the left-handed more often allergic?]

Are left handed more frequently allergic patients? With the same evaluation clinical criteria, we find a Non Right Handedness (left handed + mixed handedness) in 48/403 children (11.9%) at school in a town near our consultation place and in 152/625 (24.32%) children of the same age with a mites allergy (p less than 0.001). This non right handedness is among allergic patients more frequently observed for boys: 126/442 (28.50%) than for girls: 26/183 (14.20%). The mechanism is unknown but it has been hypothesized (Geschwind) that a male related factor might slow left hemisphere development and trouble immune system equilibration.

[Role of rhinomanometry in childhood mite allergy apropos of 76 cases]

Place for Passive Anterior Rhinomanometry (PAR) in mite allergic children. PAR is a simple method to investigate chronic or recurrent rhinopathies in children. Among 59 investigations with a Dermatophagoides pteronyssinus extract, we found 27 positive responses, 3 doubtful results and 32 negative explorations. Nasal sensitization is usually important: the liminal dose is less than 250 mcg in 17/28 cases. Most children have no bronchial sensitivity. None of 14 children with negative cutaneous and RAST tests have nasal sensitivity. When cutaneous and RAST tests are both positive, 12/16 positive PAR are found. We note a nasal sensitivity in 3/5 cases with only cutaneous test positive and 12/26 cases with only RAST tests positive. For other mites a nasal sensitivity is found in 8 out of 14 explorations (Tyrophagus and Glyciphagus especially). Among all patients when cutaneous tests, RAST tests and history are doubtful for the real part played by mites in the child rhinopathy, nasal exploration allows more explicit diagnostic and therapy.

[Does immediate-type respiratory allergy occur regarding Stemphylium? Evaluation of 39 challenge tests]

Does immediate respiratory allergy with stemphylium exist? About 39 provocation tests. We present 39 children with positive cutaneous and/or RAST tests for stemphylium mold. Provocation tests individualize 19 patients (14 boys and 4 girls, 10 to 16 years old in 17/19) with a respiratory sensitivity: 6/10 by passive anterior rhinomanometry and 13/15 by bronchial tests. Clinical symptoms are asthma and spasmodic rhinitis (14/19), predominantly from june to august. We noted a mite allergy in 11 cases and a grass pollenosis in 13 children. Positive cutaneous and/or RAST tests are found for alternaria mold in 13/19 cases. We undertook a specific hyposensitization in 14 children with a three years experience in 10 cases. Tolerance is excellent. This provocation respiratory exploration shows the important role played by stemphylium mold in the etiology of recurring respiratory incidents in children.

[Does mugwort pollenosis occur in children in the northern region?]

Is Mugwort pollenosis frequent among children in North of France? In North of France where no ragweed grows, mugwort (artemisia) is after grasses and plantago, the third pollenosis in children. Among 184 children with summer clinical signs, positive cutaneous tests with a mugwort extract are noted in 40 patients (21%). RAST are positive only in 23 on 34 children with positive cutaneous test. Among the 40 children only two are less 5 years old and 26 are more 10 years old. Respiratory provocation tests confirm in 13/19 cases a sensitization of upper or lower respiratory tract. No food allergy exists among those children.

[Platelet aggregation and platelet and plasma fatty acid levels in the child with migraine. Apropos of 40 case reports]

The authors have studied platelet aggregability in the presence of ADP and collagen in a population of 40 migrainous children between migraine attacks. They completed their investigations by a qualitative dosage in platelets and in plasma of fatty acids, precursors of prostaglandins, which are well known for their importance in platelet aggregation and vasculomotor reactions. This study was made in comparison with an equal number of controls chosen from the same age-groups. The authors didn't find the hyperaggregability observed by other authors in grown-up populations. They noticed a light-but statistically significant-diminution of linoleic acid in the platelets and in the plasma. A study based on observations does not entirely confirm for certain an alimentary origin.