A longitudinal analysis of humoral, T cellular response and influencing factors in a cohort of healthcare workers: Implications for personalized SARS-CoV-2 vaccination strategies.

Introduction: SARS-CoV-2 mRNA vaccinations elicit both virus-specific humoral and T-cell responses, but a complex interplay of different influencing factors, such as natural immunity, gender, and age, guarantees host protection. The present study aims to assess the immune dynamics of humoral, T-cell response, and influencing factors to stratify individual immunization status up to 10 months after Comirnaty-vaccine administration. Methods: To this aim, we longitudinally evaluated the magnitude and kinetics of both humoral and T-cell responses by serological tests and enzyme-linked immunospot assay at 5 time points. Furthermore, we compared the course over time of the two branches of adaptive immunity to establish an eventual correlation between adaptive responses. Lastly, we evaluated putative influencing factors collected by an anonymized survey administered to all participants through multiparametric analysis. Among 984 healthcare workers evaluated for humoral immunity, 107 individuals were further analyzed to describe SARS-CoV-2-specific T-cell responses. Participants were divided into 4 age groups: <40 and ≥40 years for men, <48 and ≥48 years for women. Furthermore, results were segregated according to SARS-CoV-2-specific serostatus at baseline. Results: The disaggregated evaluation of humoral responses highlighted antibody levels decreased in older subjects. The humoral responses were higher in females than in males (p=0.002) and previously virus-exposed subjects compared to naïve subjects (p<0.001). The vaccination induced a robust SARS-CoV-2 specific T-cell response at early time points in seronegative subjects compared to baseline levels (p<0.0001). However, a contraction was observed 6 months after vaccination in this group (p<0.01). On the other hand, the pre-existing specific T-cell response detected in natural seropositive individuals was longer-lasting than the response of the seronegative subjects, decreasing only 10 months after vaccination. Our data suggest that T-cell reactiveness is poorly impacted by sex and age. Of note, SARS-CoV-2-specific T-cell response was not correlated to the humoral response at any time point. Discussion: These findings suggest prospects for rescheduling vaccination strategies by considering individual immunization status, personal characteristics, and the appropriate laboratory tests to portray immunity against SARS-CoV-2 accurately. Deepening our knowledge about T and B cell dynamics might optimize the decision-making process in vaccination campaigns, tailoring it to each specific immune response.

Changes in 25-(OH) Vitamin D Levels during the SARS-CoV-2 Outbreak: Lockdown-Related Effects and First-to-Second Wave Difference-An Observational Study from Northern Italy.

BACKGROUND: We investigated the changes in 25-hydroxy vitamin D [25-(OH)D] concentrations values, during the first and the second pandemic waves and the impact of the lockdown periods, with their different approaches to home confinement, among different age groups. METHODS: Daily cloud-modified vitamin D UV dose (UVDVC), for the area of interest (Milano, Italy), was obtained. Single-center 25-(OH)D determinations from 40,996 individuals in a 2019 (pre-pandemic), 32,355 individuals from 1 January to 31 August 2020 (containing the first pandemic wave) and 27,684 individuals from 1 June to 30 November 2020 (containing the second wave) were compared to investigate both the effect of the lockdown on vitamin D status and the association between 25-(OH)D and SARS-CoV-2 positivity. RESULTS: No direct association was found between UVDVC, 25-(OH)D status and SARS-CoV-2 infection. The stringent confinement implemented during the first wave lockdown has not had any effect on 25-(OH)D status, although some peculiar time-restricted profile behaviors can be deduced, possibly due to vitamin D supplementation habits and features of those patients who presented to the hospital during the lockdown period. CONCLUSIONS: Although our data do not suggest any direct relationship between 25-(OH)D status, sun exposure, and SARS-CoV-2 infection, an indirect protective role cannot be excluded.

Is there a link between vitamin D status, SARS-CoV-2 infection risk and COVID-19 severity?

The outbreak of COVID-19 emerged in December 2019 rapidly spread across the globe and has become pandemic. Little is known about the protective factors of this infection, which is equally distributed between genders and different ages while severe and poor prognosis cases are strongly associated to old males and the presence of comorbidities. Thus, preventive measures aiming at reducing the number of infection and/or their severity are strongly needed. Vitamin D has got great attention and has been claimed as potentially protective against the infection since it may be associated with immunocompetence, inflammation, aging, and those diseases involved in determining the outcomes of COVID-19. This narrative review aims at collecting the literature available on the involvement of the vitamin D status in the pathogenesis of COVID-19 and the putative utility of vitamin D supplementation in the therapeutics. It emerges that a poor vitamin D status seems to associate with an increased risk of infection whereas age, gender and comorbidities seem to play a more important role in COVID-19 severity and mortality. While randomized control trials are needed to better inquire into this topic, vitamin D supplementation may be useful beside its potential effects on SARS-CoV-2 infection and COVID-19.

No significant association between vitamin D and COVID-19: A retrospective study from a northern Italian hospital.

The world is currently overwhelmed by a novel coronavirus disease (COVID-19). Clinically, COVID-19 shows a broad range of manifestations: from asymptomatic to severe and possibly lethal interstitial pneumonia. Several studies suggested the involvement of Vitamin-D (VitD) in reducing the risk of COVID-19 infections/severity. However, most of them are based on circumstantial evidences, like the association between latitude-related sunlight exposure and mortality rate, while studies based on patients' VitD measurements are still scarce. Therefore, we retrospectively analyzed the VitD levels (measured as 25-hydroxyvitamin-D) from a cohort of 347 patients admitted to a northern Italian Hospital as suspected COVID-19s. Of them, 128 were positive (83 males, aged 62.7 ± 14.2 and 45 females, aged 69.3 ± 15.6) and 219 were negative (107 males, aged 62.8 ± 19.5 and 112 females, aged 54.3 ± 20.1). The averaged VitD levels were similar in the two groups: 21.8 ± 16.1 ng/mL and 22.8 ± 14.0 ng/mL for the COVID-19 positive and negative group respectively (p-value: 0.39), as well as the percentage of individuals having VitD levels below 30 ng/mL: 78.9% and 73.5% for the COVID-19 positive and negative group respectively. Because a large portion of patients were below the suggested 30 ng/mL threshold, we can't exclude that VitD supplementation, restoring normal levels, might be beneficial in reducing the risk of infection.

A Possible Antioxidant Role for Vitamin D in Soccer Players: A Retrospective Analysis of Psychophysical Stress Markers in a Professional Team.

The health benefits of physical activity are recognized, however, high levels of exercise may lead to metabolic pathway imbalances that could evolve into pathological conditions like the increased risk of neurological disease observed in professional athletes. We analyzed the plasma/serum levels of 29 athletes from a professional soccer team playing in the Italian first league and tested the levels of psychophysical stress markers (vitamin D, creatine kinase, reactive oxygen species (ROS) and testosterone/cortisol ratio) during a period of 13 months. The testosterone/cortisol ratio was consistent with an appropriate training program. However, most of the athletes showed high levels of creatine kinase and ROS. Despite the large outdoor activity, vitamin D values were often below the sufficiency level and, during the "vitamin D winter", comparable with those of the general population. Interestingly, high vitamin D values seemed to be associated to low levels of ROS. Based on the results of our study we proposed a vitamin D supplementation as a general practice for people who perform high levels of physical exercise. Beside the known effect on calcium and phosphate homeostasis, vitamin D supplementation should mitigate the high reactivity of ROS which might be correlated to higher risk of neurodegenerative diseases observed in professional athletes.

Drainage of a Subphrenic Abscess Followed by Two-Stage Gastrectomy and Adjuvant Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Perforated Gastric Carcinoma: A Case Report.

BACKGROUND Perforated gastric cancer accounts for less than 1% of patients who present with an acute abdomen and for up to 16% of all gastric perforations. A two-stage laparoscopic procedure may be the therapeutic strategy of choice in selected patients, and adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) can reduce the incidence of peritoneal recurrence. A rare case of subphrenic abscess and gastric perforation due to carcinoma of the gastric fundus, followed by two-stage gastrectomy and adjuvant HIPEC is presented. CASE REPORT A 65-year old man presented with a left subphrenic abscess secondary to perforated gastric carcinoma. Laparoscopic drainage of the abscess was performed. Ten days later, following recovery from sepsis, the patient underwent total laparoscopic gastrectomy, and adjuvant HIPEC followed by a Roux-en-Y esophagojejunostomy. Histopathology showed an intestinal-type gastric adenocarcinoma. The tumor was staged as pT4aN0. The postoperative course was uneventful except for transient atrial fibrillation. The patient was discharged home on postoperative day 11. Systemic adjuvant chemotherapy was begun one month later. At six-month follow-up, the patient had no discomfort on eating or any other symptoms. CONCLUSIONS In this case, a two-stage laparoscopic treatment for perforated gastric carcinoma combined with adjuvant HIPEC was feasible and safe and may be considered at the time of laparoscopic gastrectomy in selected patients with perforated gastric carcinoma.

Concerning the vitamin D reference range: pre-analytical and analytical variability of vitamin D measurement.

Unlike other vitamins, the vitamin D concentration in blood varies cyclically over the course of the year in relation to genetic (gender, ethnicity, polymorphisms) and environmental factors (sunlight exposure, diet, food-related or direct vitamin D supplementation, skin pigmentation). Although the major diagnostics manufacturers have recently developed improved automated 25-hydroxy vitamin D immunoassays, the intra- and inter-laboratory variability is still high (especially at low vitamin D concentrations) which might lead to incorrect vitamin D deficiency/insufficiency diagnosis. Moreover, despite recent efforts to standardize the assay and minimize its variability, the current bias for measured vitamin D concentrations is often still above the desirable ± 10% criterion. Because the implications of low vitamin D concentrations in non-skeletal diseases are still partially unknown, international guideline recommendations for establishing meaningful ranges, at any time over the course of the year, irrespective not only of environmental and personal factors but also of instrumental variability, are needed. In this review, we discuss the main factors that influence the variability of vitamin D concentrations and whether a centile curve, individually calculated by a theoretical equation considering such factors, might be better suited than a fixed limit to assess abnormal vitamin D concentrations in otherwise healthy subjects. Vitamin D reference ranges during pregnancy, childhood, or diagnosed illnesses, which merit separate discussion, are beyond the scope of this review.

Environmentally friendly lycopene purification from tomato peel waste: enzymatic assisted aqueous extraction.

The antioxidant and anticancer properties of lycopene make it an ideal component for daily food supplements. For this reason this study investigated the possibility of extracting lycopene from tomato waste peels using a green chemistry protocol devoid of organic solvent. Cells are lysed thanks to a combination of pH changes and hydrolytic enzyme treatments. The lycopene-containing chromoplasts are then precipitated by lowering the pH and isolated through a centrifugation step. At this stage the lycopene content of the isolated chromoplasts shows a 10-fold increase (3-5% w/w, dry basis) with respect to untreated tomato peels. A further improvement in lycopene concentration is obtained by a second enzymatic treatment using a protease cocktail. This catalytic step eliminates unwanted proteins, bound to the chromoplasts, but not essential for their stability. The final product shows a lycopene content around 8-10% (w/w, dry basis), which represents a 30-fold increase with respect to the lycopene concentration of the untreated peels.

Extracellular ATP triggers and maintains asthmatic airway inflammation by activating dendritic cells.

Extracellular ATP serves as a danger signal to alert the immune system of tissue damage by acting on P2X or P2Y receptors. Here we show that allergen challenge causes acute accumulation of ATP in the airways of asthmatic subjects and mice with experimentally induced asthma. All the cardinal features of asthma, including eosinophilic airway inflammation, Th2 cytokine production and bronchial hyper-reactivity, were abrogated when lung ATP levels were locally neutralized using apyrase or when mice were treated with broad-spectrum P2-receptor antagonists. In addition to these effects of ATP in established inflammation, Th2 sensitization to inhaled antigen was enhanced by endogenous or exogenous ATP. The adjuvant effects of ATP were due to the recruitment and activation of lung myeloid dendritic cells that induced Th2 responses in the mediastinal nodes. Together these data show that purinergic signaling has a key role in allergen-driven lung inflammation that is likely to be amenable to therapeutic intervention.

The influence of lysophosphatidic acid on the functions of human dendritic cells.

Lysophosphatidic acid (LPA) is a bioactive lipid mediator which is generated by secretory phospholipase A(2). In this study, we studied the biological activity of LPA on human dendritic cells (DCs), which are specialized APCs characterized by their ability to migrate into target sites and secondary lymphoid organs to process Ags and activate naive T cells. We show that immature and mature DCs express the mRNA for different LPA receptors such as endothelial differentiation gene (EDG)-2, EDG-4, and EDG-7. In immature DCs, LPA stimulated pertussis toxin-sensitive Ca(2+) increase, actin polymerization, and chemotaxis. During the maturation process, DCs lost their ability to respond toward LPA with Ca(2+) transients, actin polymerization, and chemotaxis. However, LPA inhibited in a pertussis toxin-insensitive manner the secretion of IL-12 and TNFalpha as well as enhanced secretion of IL-10 from mature DCs. Moreover, LPA did not affect the endocytic or phagocytic capacities and the surface phenotype of DCs, although it increased the allostimulatory function of mature DC and inhibited their capacity to induce Th1 differentiation. In summary, our study implicates that LPA might regulate the trafficking, cytokine production, and T cell-activating functions of DCs.