Coronavirus SARS-CoV-2 has represented, and still represents, a real challenge from a clinical, diagnostic and therapeutic point of view. During acute infection, the increased levels of pro-inflammatory cytokines, which are involved in the pathology of disease and the development of SARS-CoV-2-induced acute respiratory disease syndrome, the life-threatening form of this infection, are correlated with patient survival and disease severity. IL-33, a key cytokine involved in both innate and adaptive immune responses in mucosal organs, can increase airway inflammation, mucus secretion and Th2 cytokine synthesis in the lungs, following respiratory infections. Similar to cases of exposure to known respiratory virus infections, exposure to SARS-CoV-2 induces the expression of IL-33, correlating with T-cell activation and lung disease severity. In this work, we analyse current evidence regarding the immunological role of IL-33 in patients affected by COVID-19, to evaluate not only the clinical impact correlated to its production but also to identify possible future immunological therapies that can block the most expressed inflammatory molecules, preventing worsening of the disease and saving patient lives.

It is well ascertained that airway inflammation has a key role in the genesis of numerous respiratory pathologies, including asthma, chronic obstructive pulmonary disease, and acute respiratory distress syndrome. Pulmonary tissue inflammation and anti-inflammatory responses implicate an intricate relationship between local and infiltrating immune cells and structural pulmonary cells. Alarmins are endogenic proteins discharged after cell injury in the extracellular microenvironment. The purpose of our review is to highlight the alterations in respiratory diseases involving some alarmins, such as high mobility group box 1 (HMGB1) and interleukin (IL)-33, and their inter-relationships and relationships with genetic non-coding material, such as microRNAs. The role played by these alarmins in some pathophysiological processes confirms the existence of an axis composed of HMGB1 and IL-33. These alarmins have been implicated in ferroptosis, the onset of type 2 inflammation and airway alterations. Moreover, both factors can act on non-coding genetic material capable of modifying respiratory function. Finally, we present an outline of alarmins and RNA-based therapeutics that have been proposed to treat respiratory pathologies.

Food allergies are immuno-mediated adverse reactions to ingestion or contact with foods, representing a widespread health problem. The immune response can be IgE-mediated, non-IgE-mediated, or with a mixed mechanism. The role of innate immunity and alarmins in the pathogenesis of diseases such as asthma and atopic dermatitis is well known. Some authors have investigated the correlation between alarmins and food allergies, often obtaining interesting results. We analyzed articles published in English from the last 22 years present on PubMed concerning the role of alarmins in the pathogenesis of food allergies and their potential use as disease biomarkers, response biomarkers to therapy, or potential therapeutic targets. Nuclear alarmins (TSLP, IL-33, IL-25) appear to have a critical role in IgE-mediated allergies but are also implicated in entities such as eosinophilic esophagitis. Calprotectin and defensins may play a role as disease biomarkers and could help predict response to therapy, although results in the literature are often conflicting. Despite the promising results, more studies on humans still need to be conducted. Deepening our knowledge regarding alarmins and their involvement in food allergies could lead to the development of new biological therapies, significantly impacting patients’ quality of life.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is the most bothersome phenotype of chronic rhinosinusitis, which is typically characterized by a Type 2 inflammatory reaction, comorbidities and high rates of nasal polyp recurrence, causing severe impact on quality of life. Nasal polyp recurrence rates, defined as the number of patients undergoing revision endoscopic sinus surgery, are 20% within a 5 year period after surgery. The cornerstone of CRSwNP management consists of anti-inflammatory treatment with local corticosteroids. We performed a literature review regarding the therapeutic strategies used to prevent nasal polyp recurrence after surgical treatment. Finally, we report an in vitro study evaluating the efficacy of lysine–acetylsalicylic acid and other non-steroidal anti-inflammatory drugs (ketoprofen and diclofenac) on the proliferation of fibroblasts, obtained from nasal polyp tissue samples. Our study demonstrates that diclofenac, even more so than lysine–acetylsalicylic acid, significantly inhibits fibroblast proliferation and could be considered a valid therapeutic strategy in preventing CRSwNP recurrence.

Lime (Citrus aurantiifolia) is a plant belonging to the family of Rutaceae and to the genus Citrus. The fruit is widely used in the United States, Mexico, Southeast Asia, Latin America, but is increasingly widespread all over the world. It is used as a fresh fruit, in the preparation of foods, sweets and drinks and its oils are used in the cosmetic and pharmaceutical industry. The main adverse reactions to lime seem to be represented by contact dermatitis, allergic and phototoxic type. In the context of allergic forms, several allergens have been identified in the citrus family, the main one being limonene, but no noteworthy cross-reactivity has been identified. However, a case of fruit protein contact dermatitis has been described, showing sensitization to other fruits, such as kiwi, avocado, pineapple and apple. There are several molecules responsible for phototoxic reactions and mainly belonging to the coumarin and furocoumarins families. Reactions related to ingesting the fruit or inhaling pollen from the tree appear to be rare, as there are no known cases reported in the literature. The increasing diffusion of lime in Europe must pay attention to possible adverse reactions due to contact with this fruit, which seem destined to increase in future years. Further importance must be placed on patch tests and on the possibility of using alternative extracts to classic fragrance mixes.