Background: Cow's milk protein allergy (CMPA) represents a major health concern in Tunisia, with diagnostic challenges influencing disease prognosis. Molecular allergen testing has emerged as a valuable tool to enhance diagnostic accuracy and predict disease persistence.Objective: This study aims to characterize the clinical and epidemiological features of CMPA in a Tunisian population, with a particular focus on the role of molecular allergens in assessing disease chronicity.Methods: A retrospective analysis was conducted on 262 cases of IgE-mediated CMPA diagnosed at the Pasteur Institute of Tunis between 2020 and 2023. Sensitization to molecular allergens was assessed using ImmunoCAP (Phadia 100).Results: CMPA symptoms predominantly manifested in infancy (94%, 246/262), with a male predominance (sex ratio: 1.6). Acute reactions were the most frequent presentation (69.9%, 79/113), and polysensitization was common (81%, 212/262), particularly to β-lactoglobulin. Spontaneous resolution occurred in approximately 33% of cases (29/87), with a mean age of 3 years and 8 months. Persistent CMPA was significantly associated with elevated IgE levels to whole milk, β-lactoglobulin, and casein (p < 0.05). ROC curve analysis identified predictive thresholds for disease persistence, including 4.2 kU/L for whole milk-specific IgE and 0.37 kU/L for casein-specific IgE (p = 0.006).Conclusion: Molecular allergen testing improves CMPA diagnosis and offers critical prognostic insights. The identification of IgE thresholds may facilitate early risk stratification and guide personalized management strategies.

The interplay between the cytokine network and antipsychotic treatment in schizophrenia remains poorly understood. This study aimed to investigate the impact of psychotropic medications on serum levels of IFN-γ, IL-4, TGF-β1, IL-17, and BAFF, and to explore their relationship with psychopathological features. We recruited 63 patients diagnosed with schizophrenia in the acute phase, all of whom were either drug-naïve or had been drug-free for at least three months. Serum levels of IL-4, IFN-γ, TGF-β1, IL-17, and BAFF were measured at baseline and after six months of antipsychotic treatment. The severity of symptoms was assessed using the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Positive Symptoms (SAPS), and the Scale for the Assessment of Negative Symptoms (SANS). Fifty-two patients completed the six-month follow-up for immunoassay analysis. Antipsychotic treatment led to a significant decrease in serum levels of IFN-γ, TGF-β1, and IL-17, alongside a significant increase in BAFF levels. Changes in IFN-γ were positively correlated with SANS scores and negatively correlated with Global Assessment of Functioning (GAF) scores. Changes in TGF-β1 were negatively correlated with GAF scores. Changes in BAFF were negatively correlated with SAPS scores. Multivariable regression models were used to explore the association between cytokine level changes (IL-17, BAFF, IFN-γ, and TGF-β1) and independent variables, including demographic (gender, age), behavioral (tobacco use), clinical (schizophrenia type, disease course, date of onset, prior treatment), and biological (C-reactive protein (CRP), erythrocyte sedimentation rate (ESR)) factors, as well as standardized assessment scores. No significant associations were found, except for a significant negative correlation between TGF-β1 changes and GAF scores, as well as a positive correlation with age. Interestingly, advanced statistical analyses revealed that only changes in IL-17 and BAFF levels were significantly associated with antipsychotic treatment. Our findings suggest that antipsychotic drugs exert both pro- and anti-inflammatory effects on the cytokine network. The observed modulation of IL-17 and BAFF highlights their potential as future therapeutic targets in schizophrenia.

(1) Background: This study aimed to compare the immunogenicity of the mix-and-match CoronaVac/BNT162b2 vaccination to the homologous CoronaVac/CoronaVac regimen. (2) Methods: We conducted a simple-blinded randomized superiority trial to measure SARS-CoV-2 neutralization antibodies and anti-spike receptor binding domain (RBD) IgG concentrations in blood samples of participants who had received the first dose of CoronaVac vaccine followed by a dose of BNT162b2 or CoronaVac vaccine. The primary endpoint for immunogenicity was the serum-neutralizing antibody level with a percentage of inhibition at 90% at 21–35 days after the boost. A difference of 25% between groups was considered clinically relevant. (3) Results: Among the 240 eligible participants, the primary endpoint data were available for 100 participants randomly allocated to the mix-and-match group versus 99 participants randomly allocated to the homologous dose group. The mix-and-match regimen elicited significantly higher levels of neutralizing antibodies (median level of 96%, interquartile range (IQR) (95–97) versus median level of 94%, IQR (81–96) and anti-spike IgG antibodies (median level of 13,460, IQR (2557–29,930) versus median level of 1190, IQR (347–4964) compared to the homologous group. Accordingly, the percentage of subjects with a percentage of neutralizing antibodies > 90% was significantly higher in the mix-and-match group (90.0%) versus the homologous (60.6%). Interestingly, no severe events were reported within 30 days after the second dose of vaccination in both groups. (4) Conclusions: Our data showed the superiority of the mix-and-match CoronaVac/BNT162b2 vaccination compared to the CoronaVac/CoronaVac regimen in terms of immunogenicity, thus constituting a proof-of-concept study supporting the use of inactivated vaccines in a mix-and-match strategy while ensuring good immunogenicity and safety.

Shrimp allergy has emerged as a growing health concern in Tunisia, likely due to changing dietary habits. This study aimed to characterize the clinical features of shrimp-allergic patients and investigate potential cross-reactivity with house dust mites (HDMs) and snails using in vitro diagnostic methods. Thirty-one patients with a self-reported history of shrimp allergy were referred to the Clinical Immunology Department of the Pasteur Institute of Tunis. Total IgE and Serum-specific IgE (sIgE) levels to shrimp, snail, and HDMs, as well as recombinant allergens rPen a1 and rDer p10, were measured using the ImmunoCAP® immunoassay. The study population consisted mainly of young adults [mean age: 15.5 years (10–27.2)], with a male-to-female ratio of 1.4. The most common symptoms were oropharyngeal pruritus and urticaria. Shrimp allergy was confirmed in 54.8% of patients, with a median sIgE titer of 0.18 [0.03–28.8] kUA/L. Among these patients, 58.8% exhibited cross-reactivity, predominantly with snails [median sIgE: 3.07 (0.04–16.85) kUA/L]. Among shrimp-allergic patients, 70.5% tested positive for rPen a1 [median sIgE: 28.42 (5.78–51.05) kUA/L], while 58.8% were positive for rDer p10 (median sIgE: 0.56 [5 × 10⁻⁵–87.95] kUA/L). The median total IgE level was 297 [158.6–475] IU/ml, significantly higher in shrimp-allergic patients (p = 0.005). The median shrimp sIgE/total IgE ratio was 0.001 [0–0.069], also significantly elevated in shrimp-sensitized individuals (p = 0.005). Multivariable analysis showed significant correlations between total IgE and shrimp sIgE, rPen a1, and rDer p10 levels (p = 0.043, p = 0.045, p = 0.043, respectively), while no correlation was found with d1 or snail sIgE after adjusting for age. rDer p10 and f24 were the strongest predictors of sIgE to snail, with standardized coefficients of 8.785 and −5.028, respectively. However, these associations did not reach statistical significance. This study underscores the critical role of tropomyosin as a primary allergen in shrimp allergy in Tunisia, highlighting its importance in immunodiagnosis and its strong association with HDMs and snail sensitization. Further research is needed to explore HDMs sensitization in patients who are negative for rPen a1 and rDer p10.

Background: Allogeneic hematopoietic stem cell transplantation (ASCT) induces acquired immunodeficiency, potentially altering vaccine response. Herein, we aimed to explore the clinical tolerance and the humoral and cellular immune responses following anti-SARS-CoV-2 vaccination in ASCT recipients. Methods: A prospective, non-randomized, controlled study that involved 43 ASCT subjects and 31 healthy controls. Humoral response was investigated using the Elecsys^® test anti-SARS-CoV-2. Cellular response was assessed using the QFN^® SARS-CoV-2 test. The lymphocyte cytokine profile was tested using the LEGENDplex™ HU Th Cytokine Panel Kit (12-plex). Results: Adverse effects (AE) were observed in 69% of patients, encompassing pain at the injection site, fever, asthenia, or headaches. Controls presented more side effects like pain in the injection site and asthenia with no difference in the overall AE frequency. Both groups exhibited robust humoral and cellular responses. Only the vaccine transplant delay impacted the humoral response alongside a previous SARS-CoV-2 infection. Noteworthily, controls displayed a Th1 cytokine profile, while patients showed a mixed Th1/Th2 profile. Conclusions: Pfizer-BioNTech^® anti-SARS-CoV-2 vaccination is well tolerated in ASCT patients, inducing robust humoral and cellular responses. Further exploration is warranted to understand the impact of a mixed cytokine profile in ASCT patients.

Muscle biopsy (MB) is an important tool to help differentiate idiopathic inflammatory myopathies (IIMs) from hereditary muscular diseases (HMDs). The usefulness of immunohistochemical stains of the major histocompatibility complex class I and the membrane attack complex are controversial, as both may be identified in some HMDs. More sensitive markers of IIMs have recently been used, such as myxovirus resistance A (MxA), a type I interferon-inducible protein. We selected skeletal MB samples from 81 patients diagnosed with IIM and HMD harbouring overt inflammatory infiltrates on their MBs in the period between March 2022 and September 2024. Two groups were identified: the IIM group (46 cases) and the HMD group (35 cases). We characterized and compared the patterns of MxA protein expression among the two groups. In the IIM group, positive sarcoplasmic MxA expression was detected on the myofibres of 10 patients (24%), among whom were eight dermatomyositis patients. In the HMD group, we did not identify any sarcoplasmic positivity. However, five patients (14%) showed positive labelling restricted to the sarcolemmal membrane, including non-necrotic or regenerating fibres. Our study demonstrates the value of MxA for increasing dermatomyositis diagnostic accuracy and suggests the potential role of interferon type I in the pathophysiology of HMD.