The role of skin tests with polyethylene glycol and polysorbate 80 in the vaccination campaign for COVID-19: results from an Italian multicenter survey.

Summary: Background. International guidelines suggested skin tests with Polyethylene-glycol (PEG) and polysorbate 80 (PS-80), to investigate a possible hypersensitivity to these excipients either to identify subjects at risk of developing allergic reactions to Covid-19 vaccines, or in patients with suspected IgE mediated hypersensitivity reactions (HR) to the Covid-19 vaccine. The main purpose of this study was to investigate the prevalence of PEG and PS sensitization in patients with a clinical history of HR to drugs containing PEG/PS and in patients with a suspected Covid-19 vaccine immediate HR. Methods. This was a multicenter retrospective study conducted by allergists belonging to 20 Italian medical centers. Skin testing was performed in 531 patients with either a clinical history of suspected hypersensitivity reaction (HR) to drugs containing PEG and/or PS-80 (group 1:362 patient) or a suspected HR to Covid-19 vaccines (group 2: 169 patient), as suggested by the AAIITO/SIAAIC guidelines for the "management of patients at risk of allergic reactions to Covid-19 vaccines" [1]. Results. 10/362 (0.02%) had positive skin test to one or both excipients in group 1, 12/169 (7.1%) in group 2 (p less than 0.01). In group 2 HRs to Covid-19 vaccines were immediate in 10/12 of cases and anaphylaxis occurred in 4/12 of patients. Conclusions. The positivity of skin test with PEG and or PS before vaccination is extremely rare and mostly replaceable by an accurate clinical history. Sensitization to PEG and PS has to be investigated in patients with a previous immediate HR to a Covid-19 vaccine, in particular in patients with anaphylaxis.

Vespa velutina nigrithorax venom allergy: inhibition studies approach for the choice of specific immunotherapy.

Summary: Vespa velutina nigrithorax (VVN), commonly known as Asian wasp because endemic in Asia, represents an alien species in Europe. VVN can induce allergic reactions similar to those caused by other Hymenoptera and death after VVN stings, presumably due to fatal allergic reactions, has been reported. In the treatment of Hymenoptera venom hypersensitivity, specific immunotherapy (VIT) is highly effective. Currently, there is no specific available VIT for VVN, so it is relevant to assess if patients stung by VVN and showing allergic reactions could be treated with the Hymenoptera commercially available extracts Vespa crabro (VC) and Vespula spp (Vspp) or if they need the specific VIT with VVN venom extract. Methods. Four patients with a clinical history of systemic reactions after VVN sting were evaluated. Serum specific IgE were assayed quantitatively with an automated fluoro-enzyme immunoassay ImmunoCAP™ Specific IgE by Phadia™ 1000 System (Thermo Fisher Scientific, Uppsala, Sweden) for VC, Vspp and VVN. Cap inhibition assays were performed incubating serum samples with 200 µl of each venom at increasing concentrations and subsequently specific IgE against each of the venoms were determined in the samples by Phadia™ 250 System (Thermo Fisher Scientific, Uppsala, Sweden). Results. Our results suggested that both Vspp and VC venoms were able to inhibit the specific IgE for VVN, although the VC compared to the Vspp venom showed a higher inhibition. Conclusions. Our inhibition studies suggested that VIT with VC venom, nowadays when there is not specific available VIT for VVN, may be more effective than Vspp VIT in patients with VVN sting reactions.

Diagnostic approach to hypersensitivity reactions to iodinated contrast media: a single-center experience on 98 patients.

Summary: Adverse reactions to iodinated contrast media (ICM) are reported in 1%-3% of diagnostic procedures. They represent a relevant problem involving patients' safety as well as relevant costs for healthcare systems. Premedication with antihistamines and corticosteroids is still widely used, but evidence of its efficacy is lacking and there is a risk for under-estimation of possible severe adverse reactions to ICM in those who undergo premedication. Data from 98 patients with a previous reaction to ICM that consecutively referred to our unit between 2015 and 2018 were retrospectively analyzed. They underwent an allergologic workup comprehending skin tests and drug provocation tests (DPT) with ICM. The skin test showed a very high negative predictive value (NPV) compared to DPT in patients with a previous immediate adverse reaction, while the NPV in patients with a previous delayed adverse reaction was lower. After completion of the allergologic workup, 94 patients (95.9%) could tolerate a DPT with the culprit or alternative ICM. Subsequently, 90 patients were reached by phone to assess if they had been re-exposed to ICM for radiologic procedure. Thirty-nine patients had been re-exposed, without any premedication in 13 cases: 12 of them had tolerated the ICM, while one reacted again despite a negative DPT with the same ICM. Overall, the NPV of this protocol was elevated (92.3%) for patients undergoing DPT and subsequent exposure to the same ICM in a real-life setting. Collaboration between the prescribing physician, the radiologist and the allergist, and an accurate allergologic workup are essential to ensure maximum safety for the patient.

Allergic reactions after vaccination: translating guidelines into clinical practice.

Summary: Vaccination represents one of the most powerful medical interventions on global health. Despite being safe, sustainable, and effective against infectious and in some cases also non-infectious diseases, it's nowadays facing general opinion's hesitancy because of a false perceived risk of adverse events. Adverse reactions to vaccines are relatively rare, instead, and those recognizing a hypersensitivity mechanism are even rarer. The purpose of this review is to offer a practical approach to adverse events after vaccination, focusing on immune-mediated reactions with particular regard to their recognition, diagnosis and management. According to clinical features, we propose an algorythm for allergologic work-up, which helps in confirming hypersensitivity to vaccine, nonetheless ensuring access to vaccination. Finally, a screening questionnaire is included, providing criteria for immunisation in specialized care settings.

Shrimp Allergy: Analysis of Commercially Available Extracts for In Vivo Diagnosis.

BACKGROUND AND OBJECTIVE: Skin prick testing (SPT) with commercial extracts is the first step in the diagnosis of shrimp allergy, although its clinical efficiency is unknown. Objective: To analyze the clinical usefulness of all commercial crustacean extracts available for SPT in Italy. METHODS: We performed a multicenter study of 157 shrimp-allergic patients who underwent SPT with 5 commercial crustacean extracts and with house dust mite (HDM) extract. Commercial extracts were analyzed using SDS-PAGE and compared with a freshly prepared in-house shrimp extract. IgE to Pen a 1/Pen m 1, Pen m 2, and Pen m 4 was determined, and immunoblot analysis was performed on a large number of sera. RESULTS: The skin reactions caused by commercial crustacean extracts were extremely heterogeneous, resulting in 32 clinical profiles, with marked differences in protein content and missing proteins at molecular weights corresponding to those of major shrimp allergens. Only strong Pen a 1/Pen m 1 reactors reacted to both HDM and all 5 commercial extracts in SPT. Most patients, including those who were tropomyosin-negative, reacted to HDM. Patients reacted to a large and variable array of proteins, and IgE reactivity was common at high molecular weights (>50 kDa). CONCLUSIONS: The in vivo diagnosis of shrimp allergy must continue to be based on SPT with fresh material. Shrimp-allergic patients frequently react to a number of ill-defined high-molecular-weight allergens, thus leaving currently available materials for component-resolved diagnosis largely insufficient. Mites and crustaceans probably share several allergens other than tropomyosin.

Heterogenity of IgE response to walnut and hazelnut in Italian allergic patients.

BACKGROUND: The prevalence of IgE reactivity against genuine walnut and hazelnut allergens is poorly defined. OBJECTIVE: The IgE response to walnut and hazelnut was investigated in Italian patients with primary allergy to these nuts. METHODS: Sera from 36 patients allergic to hazelnut and/or walnut, not reactive to PR-10, profilin, and LTP, underwent immunoblot analysis with extracts of both nuts. RESULTS: Most patients had a history of systemic symptoms following the ingestion of the offending food(s). Twelve patients were sensitized to both walnut and hazelnut, and 13 were sensitized to other nuts and seeds (cashew, peanut, sesame, pine nut, almond, Brazil nut, and pistachio). On walnut immunoblot, the 7 sera which scored positive showed much variability in their IgE profile. Two reacted uniquely at 10 kDa, and the others at 35 , 40, 45, 50, 67, and > 67 kDa. The profiles obtained under reducing and non-reducing conditions showed several differences. The 7 sera positive on hazelnut immunoblot under reducing conditions recognized sera at 10 kDa and at <10 kDa (n=1), 20 kDa (n=4), at about 22, 24, 30, 40, 43, 58, 60, and 90 kDa, and higher m.w. in other cases. Under non-reducing conditions IgE reactivity at 20, 28, 35, 40, 45, 60, 90, and 100 kDa, was detected. Only two sera scored positive under both conditions and showed an IgE profile that partly changed from one assay to another. CONCLUSION: The current list of walnut and hazelnut allergens is far from being complete. Both reducing and non-reducing conditions are needed to detect IgE reactivity in individual patients.

Shrimp allergy in Italian adults: a multicenter study showing a high prevalence of sensitivity to novel high molecular weight allergens.

BACKGROUND: Shrimp is a frequent cause of food allergy worldwide. Besides tropomyosin, several allergens have been described recently. OBJECTIVE: We investigated which allergens are involved in Italian shrimp-allergic adults. METHODS: Sera from 116 shrimp-allergic patients selected in 14 Italian allergy centers were studied. Skin prick tests with house dust mite (HDM) as well as measurements of IgE to Pen a 1 (shrimp tropomyosin) and whole shrimp extract were performed. All sera underwent shrimp immunoblot analysis, and inhibition experiments using HDM extract as inhibitor were carried out on some Pen a 1-negative sera. RESULTS: Immunoblots showed much variability. IgE reactivity at about 30 kDa (tropomyosin) was found in <50% of cases, and reactivity at about 67 kDa and >90 kDa was frequent. Further reactivities at 14-18, 25, 43-50, about 60 and about 80 kDa were detected. Most subjects had a history of shrimp-induced systemic symptoms irrespective of the relevant allergen protein. IgE to Pen a 1 were detected in sera from 46 (41%) patients. Skin reactivity to HDM was found in 43/61 (70%) Pen 1-negative subjects and inhibition studies showed that pre-adsorption of sera with HDM extract induced a marked weakening of the signal at >67 kDa. CONCLUSIONS: Several allergens other than tropomyosin are involved in shrimp allergy in adult Italian patients. Some hitherto not described high molecular weight allergens seem particularly relevant in this population and their cross-reactivity with HDM allergens makes them novel potential panallergens of invertebrates.

Wellbeing, illness perception and coping strategies in Italian Celiac patients.

The clinical features of Celiac Disease (CD) are heterogeneous and both severity and extent of villous atrophy do not correlate with clinical presentation. This study aims to evaluate the psychological wellbeing of CD patients with a similar clinical pattern and to explore whether patients with different levels of wellbeing differed in illness perception and coping strategies. CD outpatients with proven diagnosis filled in validated questionnaires to investigate wellbeing (PGWBI), illness perception (IPQ-R) and coping style (COPE). One hundred and four patients underwent data analysis. Compared to Italian reference sample, CD patients reported a significantly reduced PGWBI total score (p<0.001), self-control (p<0.001), general health (p=0.002) and vitality (p<0.001) and increased anxiety (p=0.009). 7.7% of patients reported a positive wellbeing, 40.4% distress absence, 28.8% a moderate distress and 23.1% a severe distress. Patients with distress showed a different illness perception and reported more frequently two dysfunctional strategies: focus on and venting emotions (p= 0.009) and substance abuse (p= 0.01) compared to those having a positive wellbeing. A high percentage of CD patients experience distress and differ from those who reach wellbeing in illness perception and use of coping strategies. Assessing subjective viewpoint with standardized methods can provide useful information for a better management of CD patients.

Cross reactivity between European hornet and yellow jacket venoms.

BACKGROUND: Cross-reactions between venoms may be responsible for multiple diagnostic positivities in hymenoptera allergy. There is limited data on the cross-reactivity between Vespula spp and Vespa crabro, which is an important cause of severe reactions in some parts of Europe. We studied by CAP-inhibition assays and immunoblotting the cross-reactivity between the two venoms. METHODS: Sera from patients with non discriminative skin/CAP positivity to both Vespula and Vespa crabro were collected for the analyses. Inhibition assays were carried out with a CAP method, incubating the sera separately with both venoms and subsequently measuring the specific IgE to venoms themselves. Immunoblotting was performed on sera with ambiguous results at the CAP-inhibition. RESULTS: Seventeen patients had a severe reaction after Vespa crabro sting and proved skin and CAP positive also to vespula. In 11/17 patients, Vespula venom completely inhibited IgE binding to VC venom, whereas VC venom inhibited binding to Vespula venom only partially (<75%). In 6 subjects the CAP-inhibition provided inconclusive results and their sera were analysed by immunoblotting. The SDS-PAGE identified hyaluronidase, phospholipase A1 and antigen 5 as the main proteins of the venoms. In 5 sera the levels of IgE against antigen 5 of Vespa crabro were higher than IgE against Vespula germanica, thus indicating a true sensitisation to crabro. CONCLUSION: In the case of multiple positivities to Vespa crabro and Vespula spp the CAP inhibition is helpful in detecting the cross-reactivities.

Purified protein derivative of Mycobacterium tuberculosis and excretory-secretory antigen(s) of Toxocara canis expand in vitro human T cells with stable and opposite (type 1 T helper or type 2 T helper) profile of cytokine production.

A large series of T cell clones (TCC) specific for purified protein derivative (PPD) of Mycobacterium tuberculosis (total 60) or Toxocara canis excretory/secretory (TES) antigen (total 69) were established from the peripheral blood of two healthy individuals and analyzed for their profile of cytokine production in response to stimulation with either the specific antigen or the polyclonal activator phorbol myristate acetate plus anti-CD3 antibody. Under both these experimental conditions, the great majority of PPD-specific TCC secreted IL-2 and IFN-gamma but not, or limited amounts of, IL-4 and IL-5. In contrast, most TES-specific TCC secreted IL-4 and IL-5 but not, or limited amounts of, IL-2 and IFN-gamma. PPD-specific TCC that failed to secrete IL-4 and IL-5, and TES-specific TCC that failed to secrete IL-2 and IFN-gamma, were found to lack transcripts for IL-4 and IL-5, or for IL-2 and IFN-gamma, respectively. During the course of the study, over a 6-mo period, the functional phenotype of both TES- and PPD-specific TCC was repeatedly assessed and remained constant. These data demonstrate that T cells with stable Th1 or Th2 functional pattern exist not only in mice but also in humans and suggest that in the course of natural immunization certain infectious agents preferentially expand T cell subsets with stable and definite profile of cytokine production.

Defective in vitro production of gamma-interferon and tumor necrosis factor-alpha by circulating T cells from patients with the hyper-immunoglobulin E syndrome.

Circulating T cells from four patients with the hyper-IgE syndrome were found to produce significantly lower concentrations of interferon-gamma (IFN-gamma) in response to stimulation with phytohemagglutinin (PHA) than did T cells from eight age-matched healthy controls, three patients with atopic dermatitis and one patient with chronic granulomatous disease. A clonal analysis revealed that patients with hyper-IgE syndrome had markedly lower proportions of circulating T cells able to produce IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) in comparison with controls. In contrast, the proportions of peripheral blood T cells able to produce IL-4 or IL-2 were not significantly different in patients and controls. All the four patients with hyper-IgE syndrome showed high proportions of circulating CD4+ helper T cells able to induce IgE synthesis in allogeneic B cells, as well. Such an activity for IgE synthesis appeared to be positively correlated with IL-4 production by T cells and inversely related to the ability of the same T cells to produce IFN-gamma. Since IFN-gamma exerts an inhibitory effect on the synthesis of IgE and both IFN-gamma and TNF-alpha play an important role in inflammatory reactions, we suggest that the defective production of IFN-gamma may be responsible for hyperproduction of IgE and the combined defect of IFN-gamma and TNF-alpha may contribute to the undue susceptibility to infections seen in patients with hyper-IgE syndrome.

Diagnostic accuracy of anti-gliadin antibodies in Non Celiac Gluten Sensitivity (NCGS) patients: A dual statistical approach.

BACKGROUND: Gluten is the target of several diseases such as wheat allergy (WA), celiac disease (CD) and non-celiac gluten sensitivity (NCGS). NCGS is a new clinical entity characterized by gastrointestinal and extraintestinal symptoms comparable to those of CD patients but to date still lacking of specific biomarkers so that NCGS diagnosis can be reached only by excluding CD and WA, and based on the direct association between gluten ingestion and symptoms onset. Previous studies showed that antigliadin antibodies (AGA) IgG are the most prevalent positive antibodies in NCGS population. AIM: The first aim of the study was to estimate AGA distribution and prevalence in a NCGS population. The second aim was to identify a serological pattern to help the diagnosis and/or to mark the NCGS disease. METHODS: Sera from 59 patients with suspected NCGS, 90 CD patients and 70 healthy individuals were assessed for AGA IgG/IgA, IgG/IgA deamidated gliadin peptide antibodies (DGP-AGA), tissue transglutaminase antibodies IgA (tTGA), endomysial antibodies IgA (EmA) and HLA typing (Eurospital, Trieste, Italy). RESULTS: We evaluated data by a dual statistical approach: logistic regression and receiver operating characteristic (ROC) analysis; therefore, we showed a poor diagnostic accuracy of AGA IgG in NCGS condition. CONCLUSION: Our preliminary data showed that AGA IgG didn't seem to be a strongly sensitive marker, even if it has been recently proposed as promising marker for NCGS condition, together with negativity for other celiac disease related antibodies. It can partially help the NCGS diagnosis, if it is integrated in the overall management of the patient. More in-depth clinical and laboratory researches are mandatory.

Cytolytic T lymphocytes with natural killer activity in thyroid infiltrate of patients with Hashimoto's thyroiditis: analysis at clonal level.

T Lymphocytes from thyroid infiltrates and peripheral blood (PB) of 3 patients with Hashimoto's thyroiditis (HT) were cloned using a microculture system previously shown to allow the clonal expansion of virtually all PB T lymphocytes from normal individuals. The phenotypic and functional features of a total number of 153 clones from thyroid infiltrates and 206 clones from PB were examined and compared with those of 272 clones derived from normal PB and spleens. The majority of clones derived from thyroid infiltrates of patients with HT had the cytotoxic/suppressor (T8+) phenotype, whereas the majority of clones from PB expressed the helper/inducer (T4+) phenotype. In addition, a consistent proportion (25%) of clones derived from PB of one patient had a phenotype (T3+T4-T8-) that was only occasionally found on clones obtained from PB or spleens of normal subjects. Most clones derived from both PB and thyroid infiltrates of the patients with HT had cytolytic activity, assessed by a lectin-dependent cytolytic assay against the murine P815 tumor cell line. The high frequency of cytotoxic T cells in thyroid infiltrates was related to the increased proportion of T8+ cells, whereas enhanced percentages of cytotoxic cell precursors with T4+ and T3+T4-T8- phenotypes primarily accounted for the high frequency of cytolytic T cells in the PB of the same patients. Many cytolytic T cell clones derived from thyroid infiltrates also had natural killer activity against human K562 and MOLT-4 target cells. These data provide the first functional analysis of T lymphocytes infiltrating the thyroid gland in patients with HT and suggest that the high proportions of cytolytic T cell precursors found in both thyroid infiltrates and PB of these patients may be of importance in determining the tissue damage in thyroid autoimmune disease.

Structure-activity relationships in cinnamamides. 1. Synthesis and pharmacological evaluation of some (E)- and (Z)-N-alkyl-alpha,beta-dimethylcinnamamides.

Two series of (E)- and (Z)-N-alkyl-alpha,beta-dimethylcinnamamide derivatives were prepared and the biological activity of these compounds was investigated in a series of pharmacological tests. All compounds tested had clear activity on the CNS; generally, this was depressant with E isomers, while Z isomers always caused marked stimulation (tremors and convulsions). Some of the E isomers also had a clear-cut anticonvulsant activity as shown by the antagonistic effect on pentylenetetrazole-induced seizures in the mouse. The NMR spectra of these compounds, which confirm their configurations, are discussed.

CD4 + T Cells from Lymph Nodes Involved by Hodgkin's Disease Showing Response in Autologous Mixed Lymphocyte Reaction, are Polyclonal.

Thirteen CD4 + T cell clones (TCCs) showing autologous mixed lymphocyte reaction (AMLR) and 12 CD4 + AMLR-negative TCCs derived from involved lymph nodes (LN) of 4 untreated patients with newly-diagnosed Hodgkin's disease (HD) were analyzed for some functional activities and for T cell receptor (TCR) gamma and beta gene rearrangement The majority of the AMLR-positive-, but only two AMLR-negative TCCs showed cytolytic potential when assayed by a lectin-dependent assay. In addition, the proportion of clones able to produce interleukin 2 (IL-2) was higher among AMLR-positive- than AMLR-negative TCCs and the amount of IL-2 synthesized by AMLR-positive TCCs was significantly greater than that of AMLR-negative TCCs. In contrast, no difference in the profile of interleukin 4 (IL-4) and interferon-gamma (IFN-γ) production between AMLR-positive- and AMLR-negative TCCs was detected When AMLR-positive TCCs were analysed for their TCR beta and gamma gene rearrangements, a highly heterogeneous pattern was found. More importantly, TCCs derived from the same donor and displaying the same kind of TCR beta and gamma gene rearrangement showed different patterns of rearrangements, suggesting that CD4 + cells from LN involved by HD, displaying such an unusual functional profile, are polyclonal.

Role of interleukins in induction and regulation of human IgE.

The studies on human IgE synthesis here summarized provide further insight into the cellular and molecular mechanisms involved in IgE regulation, as well as in the alterations responsible for IgE disregulation in some pathological conditions. They have clearly demonstrated that IL-4 is the essential factor for the induction of human IgE synthesis, since no substantial IgE production in vitro could be obtained in the absence of this lymphokine. Another T cell-derived lymphokine, IFN gamma, negatively regulates the IgE synthesis induced by IL-4. These two lymphokines can be produced by different T helper cells, as shown in mice, but they can also be the product of the same T cell clones. In such a case, the possibility that a given clone provides helper function for IgE seems to be dependent on the balance between the amounts of the two lymphokines produced. The IgE helper activity of rIL-4 appeared to be dependent on the presence in culture of appropriate concentrations of T lymphocytes, suggesting that T-B cell contact or other interleukins, such as IL-2 and IL-6, are needed in IL-4-dependent IgE synthesis. Finally, alterations of one or more of these regulatory mechanisms may play a crucial role in the pathogenesis of diseases characterized by a hyperproduction of IgE.

Uric acid metabolism in two patients with coexistent Down's syndrome and gout.

Two patients with coexistent Down's syndrome and gout are described. Although increased serum urate levels are frequently reported in Down's syndrome, only a few such patients have been described with concomitant gout. In our patients no significant alterations of the purine salvage pathway were found, and the turnover parameters of uric acid, determined by means of a 14C-labeled uric acid study, were consistent with the metabolic findings observed in normoexcretor gouty patients.