The Effect of Positive Pressure Ventilation on Acute Kidney Injury in COVID-19 Patients with Acute Respiratory Distress Syndrome: An Observational Study.

INTRODUCTION: Acute kidney injury (AKI) is frequent in critically ill COVID-19 patients and is associated with a higher mortality risk. By increasing intrathoracic pressure, positive pressure ventilation (PPV) may reduce renal perfusion pressure by reducing venous return to the heart or by increasing renal venous congestion. This study's aim was to evaluate the association between AKI and haemodynamic and ventilatory parameters in COVID-19 patients with ARDS. METHODS: This is a single-centre retrospective observational study. Consecutive patients diagnosed with COVID-19 who met ARDS criteria and required invasive mechanical ventilation were enrolled. The relationship between respiratory and haemodynamic parameters influenced by PPV and AKI development was evaluated. AKI was defined according to KDIGO criteria. AKI recovery was evaluated a month after ICU admission and patients were classified as "recovered," if serum creatinine (sCr) value returned to baseline, or as having "acute kidney disease" (AKD), if criteria for AKI stage 1 or greater persisted. The 6-month all-cause mortality was collected. RESULTS: A total of 144 patients were included in the analysis. AKI occurred in 69 (48%) patients and 26 (18%) required renal replacement therapy. In a multivariate logistic regression analysis, sex, hypertension, cumulative dose of furosemide, fluid balance, and plateau pressure were independently associated with AKI. Mortality at 6 months was 50% in the AKI group and 32% in the non-AKI group (p = 0.03). Among 36 patients who developed AKI and were discharged alive from the hospital, 56% had a full renal recovery after a month, while 14%, 6%, and 14% were classified as having an AKD of stage 0, 2, and 3, respectively. CONCLUSIONS: In our cohort, AKI was independently associated with multiple variables, including high plateau pressure, suggesting a possible role of PPV on AKI development. Further studies are needed to clarify the role of mechanical ventilation on renal function.

Posthemorrhagic hydrocephalus management in patients with necrotizing enterocolitis: a monocentric experience.

PURPOSE: Posthemorrhagic hydrocephalus (PHH) and necrotizing enterocolitis (NEC) are two comorbidities associated with prematurity. The management of patients with both conditions is complex and it is necessary to intercept them to avoid meningitis and multilocular hydrocephalus. METHODS: In a single-center retrospective study, we analyzed 19 patients with NEC and PHH admitted from 2012 to 2022. We evaluated perinatal, imaging, and NEC-related data. We documented shunt obstruction and infection and deaths within 12 months of shunt insertion. RESULTS: We evaluated 19 patients with NEC and PHH. Six cases (31.58%) were male, the median birth weight was 880 g (650-3150), and the median gestational age was 26 weeks (23-38). Transfontanellar ultrasound was performed on 18 patients (94.74%) and Levine classification system was used: 3 cases (15.79%) had a mild Levine index, 11 cases (57.89%) had moderate, and 5 cases (26.32%) were graded as severe. Magnetic resonance showed intraventricular hemorrhage in 14 cases (73.68%) and ventricular dilatation in 15 cases (78.95%). The median age at shunt insertion was 24 days (9-122) and the median length of hospital stay was 120 days (11-316). Sepsis was present in 15 cases (78.95%). NEC-related infection involved the peritoneal shunt in 4 patients and 3 of them had subclinical NEC. At the last follow-up, 6 (31.58%) patients presented with psychomotor delay. No deaths were reported. CONCLUSIONS: Although recognition of subclinical NEC is challenging, the insertion of a ventriculoperitoneal shunt is not recommended in these cases and alternative treatments should be considered to reduce the risk of meningitis and shunt malfunction.

Exploring the frontier in robotic pediatric cancer surgery: when to move forward and when to stop.

PURPOSE: In recent years, the use of robotic-assisted minimally invasive surgery in pediatric oncology has increased. Despite its benefits, its adoption remains limited. This single-center retrospective analysis examines technical nuances, indications, and surgical limitations to prevent complications. METHODS: Data from cancer patients treated robotically in 2015-2016 (Group A) and 2020-2022 (Group B) were compared. Decision-making considered tumor characteristics and risks, guided by multidisciplinary tumor board discussions. Data collected included demographics, intra/post-operative details, and tumor classifications. Statistical analysis evaluated influencing factors. RESULTS: Thirty-eight pediatric patients underwent robotic-assisted tumor resection, the median age was 5 years and weight 21.5 kg. Group A had higher median age and weight. Lesions included 23 malignant, 9 borderline, 5 benign cases; neuroblastoma (n = 19) was prevalent procedure and adrenalectomy was the predominant (28.94%). Open conversion occurred in 12 patients (31.58%), mainly due to vascular challenges (23.68%). Intraoperative complications were 10.53%, postoperative 7.9%. About 27% discharged by the third postoperative day; longer stays were needed for complex cases. All resumed post-op chemotherapy as scheduled, and all alive during follow-up. CONCLUSIONS: Our study confirms the safety and efficacy of robotic-assisted tumor resections in pediatric oncology, even during the learning phase, emphasizing the importance of learning curve, patient selection, and trocar positioning.

Efficacy of mucosal vaccination using a protozoan parasite as a vehicle for antigen delivery: IgG and neutralizing response after rectal administration of LeCoVax-2, a candidate vaccine against COVID-19.

Mucosal vaccination is regarded as a promising alternative to classical, intramuscular vaccine delivery. However, only a limited number of vaccines have been licensed for mucosal administration in humans. Here we propose Leishmania tarentolae, a protozoan parasite, as a potential antigen vehicle for mucosal vaccination, for administration via the rectal or oral routes. To test this hypothesis, we exploited L. tarentolae for the production and delivery of SARS-CoV-2 antigens. Two antigens were assayed in BALB/c mice: Lt-spike, a L. tarentolae clone engineered for the surface expression of the SARS-CoV-2 spike protein; RBD-SD1, a purified portion of the spike protein, produced by another engineered clone of the protozoon. Immune response parameters were then determined at different time points. Both antigens, administered either separately or in combination (Lt-spike + RBD-SD1, hereafter LeCoVax-2), determined significant IgG seroconversion and production of neutralizing antibodies after subcutaneous administration, but only in the presence of adjuvants. After rectal administration, the purified RBD-SD1 antigen did not induce any detectable immune response, in comparison with the intense response observed after administration of LeCoVax-2 or Lt-spike alone. In rectal administration, LeCoVax-2 was also effective when administered without adjuvant. Our results show that L. tarentolae is an efficient and safe scaffold for production and delivery of viral antigens, to be used as vaccines. In addition, rectal vaccination experiments prove that L. tarentolae is suitable as a vaccine vehicle and adjuvant for enteral vaccination. Finally, the combined preparation LeCoVax-2 can be considered as a promising candidate vaccine against SARS-CoV-2, worthy of further investigation.

Characterization of compliance phenotypes in COVID-19 acute respiratory distress syndrome.

BACKGROUND: Coronavirus disease 2019-associated acute respiratory distress syndrome (COVID-19 ARDS) seems to differ from the "classic ARDS", showing initial significant hypoxemia in the face of relatively preserved compliance and evolving later in a scenario of poorly compliant lungs. We tested the hypothesis that in patients with COVID-19 ARDS, the initial value of static compliance of respiratory system (Crs) (1) depends on the previous duration of the disease (i.e., the fewer days of illness, the higher the Crs and vice versa) and (2) identifies different lung patterns of time evolution and response to prone positioning. METHODS: This was a single-center prospective observational study. We enrolled consecutive mechanically ventilated patients with a diagnosis of COVID-19 who met ARDS criteria, admitted to intensive care unit (ICU). Patients were divided in four groups based on quartiles of initial Crs. Relationship between Crs and the previous duration of the disease was evaluated. Respiratory parameters collected once a day and during prone positioning were compared between groups. RESULTS: We evaluated 110 mechanically ventilated patients with a diagnosis of COVID-19 who met ARDS criteria admitted to our ICUs. Patients were divided in groups based on quartiles of initial Crs. The median initial Crs was 41 (32-47) ml/cmH2O. No association was found between the previous duration of the disease and the initial Crs. The Crs did not change significantly over time within each quartile. Positive end-expiratory pressure (PEEP) and driving pressure were respectively lower and greater in patients with lower Crs. Prone positioning significantly improved PaO2/FiO2 in the 4 groups, however it increased the Crs significantly only in patients in lower quartile of Crs. CONCLUSIONS: In our cohort, the initial Crs is not dependent on the previous duration of COVID-19 disease. Prone positioning improves oxygenation irrespective to initial Crs, but it ameliorates respiratory mechanics only in patients with lower Crs.

Maraviroc as a potential HIV-1 latency-reversing agent in cell line models and ex vivo CD4 T cells.

Recent studies have suggested that the CCR5 antagonist maraviroc (MVC) may exert an HIV-1 latency reversal effect. This study aimed at defining MVC-mediated induction of HIV-1 in three cell line latency models and in ex vivo CD4 T cells from six patients with suppressed viraemia. HIV-1 induction was evaluated in TZM-bl cells by measuring HIV-1 LTR-driven luciferase expression, and in ACH-2 and U1 latently infected cell lines by measuring cell-free (CFR) and cell-associated (CAR) HIV-1 RNA by qPCR. NF-κB p65 was quantified in nuclear extracts by immunodetection. In ex vivo CD4 T cells, CAR, CFR and cell-associated DNA (CAD) were quantified at baseline and 1-7-14 days post-induction (T1, T7, T14). At T7 and T14, the infectivity of the CD4 T cells co-cultured with MOLT-4/CCR5 target cells was evaluated in the TZM-bl assay (TZA). Results were expressed as fold activation (FA) with respect to untreated cells. No LTR activation was observed in TZM-bl cells at any MVC concentration. NF-κB activation was only modestly upregulated (1.6±0.4) in TZM-bl cells with 5 µM MVC. Significant FA of HIV-1 expression was only detected at 80 µM MVC, namely on HIV-1 CFR in U1 (3.1±0.9; P=0.034) and ACH-2 cells (3.9±1.4; P=0.037). CFR was only weakly stimulated at 20 µM in ACH-2 (1.7±1.0 FA) cells and at 5 µM in U1 cells (1.9±0.5 FA). Although no consistent pattern of MVC-mediated activation was observed in ex vivo experiments, substantial FA values were detected sparsely on individual samples with different parameters. Notably, in one sample, MVC stimulated all parameters at T7 (2.3±0.2 CAD, 6.8±3.7 CAR, 18.7±16.7 CFR, 7.3±0.2 TZA). In conclusion, MVC variably induces HIV-1 production in some cell line models not previously used to test its latency reversal potential. In ex vivo CD4 T cells, MVC may exert patient-specific HIV-1 induction; however, clinically relevant patterns, if any, remain to be defined.

Immunity to measles in Italian children and adolescents: a persistent problem in view of measles elimination.

BACKGROUND: Despite efforts to increase coverage by two doses of measles vaccine in Italy, measles continues to circulate, with over 13 000 cases of disease since 2013. This study aimed to evaluate immunity to measles in Italian children and adolescents. METHODS: A total of 378 serum samples from subjects aged 9 months-18 years were collected in Northern, Central and Southern regions of Italy between 2012 and 2016. Specific IgG antibodies against measles were measured by a commercial ELISA kit. RESULTS: The frequency of IgG-positive samples ranged from 10.5% in infants under 1 year to 98.3% in children aged 6-7 years. The frequency of IgG was 72.2% in subjects aged 1-2 years, 85.6% in those aged 3-5 years and 88.3 and 86.8% in those aged 8-10 and 11-18 years, respectively. In Northern Italy, IgG prevalence was consistent with data on vaccination coverage, whereas some differences were observed in samples from subjects aged more than 8 years in Central and Southern Italy. CONCLUSIONS: Our findings confirm that a large proportion of children and adolescents in Italy are still susceptible to measles. While data on first- and second-dose measles vaccination are essential, they are not sufficient to identify susceptible population cohorts to be targeted by vaccination.

Covid-19 and gender: lower rate but same mortality of severe disease in women-an observational study.

BACKGROUND: Gender-related factors might affect vulnerability to Covid-19. The aim of this study was to describe the role of gender on clinical features and 28-day mortality in Covid-19 patients. METHODS: Observational study of Covid-19 patients hospitalized in Bergamo, Italy, during the first three weeks of the outbreak. Medical records, clinical, radiological and laboratory findings upon admission and treatment have been collected. Primary outcome was 28-day mortality since hospitalization. RESULTS: 431 consecutive adult patients were admitted. Female patients were 119 (27.6%) with a mean age of 67.0 ± 14.5 years (vs 67.8 ± 12.5 for males, p = 0.54). Previous history of myocardial infarction, vasculopathy and former smoking habits were more common for males. At the time of admission PaO2/FiO2 was similar between men and women (228 [IQR, 134-273] vs 238 mmHg [150-281], p = 0.28). Continuous Positive Airway Pressure (CPAP) assistance was needed in the first 24 h more frequently in male patients (25.7% vs 13.0%; p = 0.006). Overall 28-day mortality was 26.1% in women and 38.1% in men (p = 0.018). Gender did not result an independent predictor of death once the parameters related to disease severity at presentation were included in the multivariable analysis (p = 0.898). Accordingly, the Kaplan-Meier survival analysis in female and male patients requiring CPAP or non-invasive ventilation in the first 24 h did not find a significant difference (p = 0.687). CONCLUSION: Hospitalized women are less likely to die from Covid-19; however, once severe disease occurs, the risk of dying is similar to men. Further studies are needed to better investigate the role of gender in clinical course and outcome of Covid-19.

Pharmacological inhibition of MAGL attenuates experimental colon carcinogenesis.

Colorectal cancer (CRC) is a major health problem in Western countries. The endocannabinoid 2-arachidonoyl-glycerol (2-AG) exerts antiproliferative actions in a number of tumoral cell lines, including CRC cells. Monoacylglycerol lipase (MAGL), a serine hydrolase that inactivates 2-AG, is highly expressed in aggressive human cancer cells. Here, we investigated the role of MAGL in experimental colon carcinogenesis. The role of MAGL was assessed in vivo by using the xenograft and the azoxymethane models of colon carcinogenesis; MAGL expression was evaluated by RT-PCR and immunohistochemistry; 2-AG levels were measured by liquid chromatography mass spectrometry; angiogenesis was evaluated in tumor tissues [by microvessel counting and by investigating the expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) proteins] as well as in human umbilical vein endothelial cells (HUVEC); cyclin D1 was evaluated by RT-PCR. MAGL and 2-AG were strongly expressed in tumor tissues. The MAGL inhibitor URB602 reduced xenograft tumor volume, this effect being associated to down-regulation of VEGF and FGF-2, reduction in the number of vessels and down-regulation of cyclin D1. In HUVEC, URB602 exerted a direct antiangiogenic effect by inhibiting FGF-2 induced proliferation and migration, and by modulating pro/anti-angiogenic agents. In experiments aiming at investigating the role of MAGL in chemoprevention, URB602 attenuated azoxymethane-induced preneoplastic lesions, polyps and tumors. MAGL, possibly through modulation of angiogenesis, plays a pivotal role in experimental colon carcinogenesis. Pharmacological inhibition of MAGL could represent an innovative therapeutic approach to reduce colorectal tumor progression.

Efficacy of AdipoDren® in Reducing Interleukin-1-Induced Lymphatic Endothelial Hyperpermeability.

Lymphatic leakage can be seen as a detrimental phenomenon associated with fluid retention and deposition as well as gain of weight. Moreover, lymphatic dysfunction is associated with an inflammatory environment and can be a substrate for other health conditions. A number of treatments can ameliorate lymphatic vasculature: natural substances have been used as treatment options particularly suitable for their consolidated effectiveness and safety profile. Here we report the protective effect of AdipoDren®, an association of a series of plant-derived natural complexes, on lymphatic endothelium permeability promoted by interleukin-1 beta (IL-1ß) and the associated molecular mechanisms. AdipoDren® demonstrated a protective effect on dermal lymphatic endothelial cell permeability increased by IL-1ß. Reduced permeability was due to the maintenance of tight junctions and cell-cell localisation of occludin and zonula occludens-1 (ZO-1). Moreover, AdipoDren® reduced the expression of the inflammatory key element cyclooxygenase-2 (COX-2), while not altering the levels of endothelial and inducible nitric oxide synthases (eNOS and iNOS). The upregulation of antioxidant enzymatic systems (catalase and superoxide dismutase-1, SOD-1) and the downregulation of pro-oxidant markers (p22 phox subunit of NADPH oxidase) were also evident. In conclusion, AdipoDren® would be useful to ameliorate conditions of altered lymphatic vasculature and to support the physiological functionality of the lymphatic endothelium.

H2S dependent and independent anti-inflammatory activity of zofenoprilat in cells of the vascular wall.

Cardiovascular diseases as atherosclerosis are associated to an inflammatory state of the vessel wall which is accompanied by endothelial dysfunction, and adherence and activation of circulating inflammatory cells. Hydrogen sulfide, a novel cardiovascular protective gaseous mediator, has been reported to exert anti-inflammatory activity. We have recently demonstrated that the SH containing ACE inhibitor zofenoprilat, the active metabolite of zofenopril, controls the angiogenic features of vascular endothelium through H2S enzymatic production by cystathionine gamma lyase (CSE). Based on H2S donor/generator property of zofenoprilat, the objective of this study was to evaluate whether zofenoprilat exerts anti-inflammatory activity in vascular cells through its ability to increase H2S availability. Here we found that zofenoprilat, in a CSE/H2S-mediated manner, abolished all the inflammatory features induced by interlukin-1beta (IL-1ß) in human umbilical vein endothelial cells (HUVEC), especially the NF-κB/cyclooxygenase-2 (COX-2)/prostanoid biochemical pathway. The pre-incubation with zofenoprilat/CSE dependent H2S prevented IL-1ß induced paracellular hyperpermeability through the control of expression and localization of cell-cell junctional markers ZO-1 and VE-cadherin. Moreover, zofenoprilat/CSE dependent H2S reduced the expression of the endothelial markers CD40 and CD31, involved in the recruitment of circulating mononuclear cells and platelets. Interestingly, this anti-inflammatory activity was also confirmed in vascular smooth muscle cells and fibroblasts as zofenoprilat reduced, in both cell lines, proliferation, migration and COX-2 expression induced by IL-1ß, but independently from the SH moiety and H2S availability. These in vitro data document the anti-inflammatory activity of zofenoprilat on vascular cells, reinforcing the cardiovascular protective effect of this multitasking drug.

Anti-hypertensive property of a nickel-piperazine/NO donor in spontaneously hypertensive rats.

The nickel-piperazine/NO donor compound, Ni(PipNONO)Cl, belonging to the family of compounds labelled as "metal-nonoates", due to its promising vasodilating activity, has been considered as a potential drug candidate in anti-hypertensive therapy. Drug efficacy has been evaluated in spontaneously hypertensive rats (SHR) in comparison with normotensive animals (C57BL/6 mice and WKY rats). In normotensive animals the metal-nonoate maintained blood pressure at basal level both following acute administration and after 30 days of treatment. In SHR, Ni(PipNONO)Cl reduced blood pressure in the dose range of 3-10mg/kg. When compared with a commercial NONOate, DETA/NO, used at the same doses, Ni(PipNONO)Cl was more active in reducing blood pressure in SHR than DETA/NO in the first two weeks, while the effect of the two molecules was similar in the third and fourth week. The degradation and control compound Ni(Pip)Cl2 had no effect on blood pressure and heart rate in same animal models. Remarkably, the blood pressure reduction induced by the new NO-donor Ni(PipNONO)Cl does not evoke changes in the heart rate and tolerance. Considering the mechanisms of vascular protection, 30 days of administration of Ni(PipNONO)Cl improved endothelial function in SHR by upregulating endothelial NO synthase (eNOS) through increased eNOS protein levels and downregulated Caveolin-1 (Cav-1), and by increasing superoxide dismutase 1 (SOD1) protein level in aortae. In cultured endothelial cells Ni(PipNONO)Cl restored the cell functions (cytoskeletal protein expression, migration and proliferation) altered by the inflammatory mediator interleukin-1ß (IL-1ß), impairing the endothelial to mesenchimal transition. In conclusion, Ni(PipNONO)Cl maintained unaltered blood pressure in normotensive mice and rats, and it exerted anti-hypertensive effect in SHR through the restoration of vascular endothelial protective functions.

Neuronal effects of a nickel-piperazine/NO donor complex in rodents.

In the brain, NO is a very important molecule in the regulation of cerebral and extra cerebral cranial blood flow and arterial diameters. It is also importantly involved in many neuronal functions and innumerable roles of NO in many brain related disorders including epilepsy, schizophrenia, drug addiction, anxiety, major depression, have been postulated. The present study aimed to explore the neuronal role exerted by the metal-nonoate compound Ni(PipNONO)Cl, a novel NO donor whose vascular protective effects have been recently demonstrated. Ni(PipNONO)Cl showed antidepressant-like properties in the tail suspension test and antiamnesic activity in the passive avoidance test in the absence of any hypernociceptive response to a mechanical stimulus. These effects were related to the NO-releasing properties of the compound within the central nervous system as demonstrated by the increase of iNOS levels in the brain, spinal cord and dura mater. The modulation of neuronal functions appeared after acute and repeated treatment, showing the lack of any tolerance to neuronal effects. At the dose used (10 mg/kg i.p.), Ni(PipNONO)Cl did not induce any visible sign of toxicity and experiments were performed in the absence of locomotor impairments. In addition to the NO-related neuronal activities of Ni(PipNONO)Cl, the decomposition control compound Ni(Pip)Cl2 showed anxiogenic-like and procognitive effects. The present findings showed neuronal modulatory activity of Ni(PipNONO)Cl through a NO-mediated mechanism. The activities of the decomposition compound Ni(Pip)Cl2 attributed to Ni(PipNONO)Cl the capability to modulate additional neuronal functions independently from NO releasing properties extending and improving the therapeutic perspectives of the NO donor.

Protective effects of novel metal-nonoates on the cellular components of the vascular system.

At the cardiovascular level, nitric oxide (NO) controls smooth muscle functions, maintains vascular integrity, and exerts an antihypertensive effect. Metal-nonoates are a recently discovered class of NO donors, with NO release modulated through the complexation of the N-aminoethylpiperazine N-diazeniumdiolate ligand to metal ions, and thus representing a significant innovation with respect to the drugs traditionally used. In this study, we characterized the vascular protective effects of the most effective compound of this class, Ni(PipNONO)Cl, compared with the commercial N-diazeniumdiolate group derivate, diethylenetriamine/nitric oxide (DETA/NO). Ni(PipNONO)Cl induced a concentration-dependent relaxation of precontracted rat aortic rings. The ED50 was 0.67 µM, compared with 4.3 µM obtained with DETA/NO. When tested on cultured microvascular endothelial cells, Ni(PipNONO)Cl exerted a protective effect on the endothelium, promoting cell proliferation and survival in the picomolar range. The administration of Ni(PipNONO)Cl to vascular smooth muscle cells reduced the cell number, promoting their apoptosis at a high concentration (10 µM). Inhibition of smooth muscle cell migration, a hallmark of atherosclerosis, was accompanied by cytoskeletal rearrangement and loss of lamellipodia. When added to isolated platelets, Ni(PipNONO)Cl significantly reduced ADP-induced aggregation. Since atherosclerosis is accompanied by an inflammatory environment, cultured endothelial cells were exposed to interleukin (IL)-1ß. In the presence of IL-1ß, Ni(PipNONO)Cl inhibited cyclooxygenase-2 and inducible nitric oxide synthase upregulation, and reduced endothelial permeability and the platelet and monocyte adhesion markers CD31 and CD40 at the plasma membrane. Overall, these data indicate that Ni(PipNONO)Cl exerts vascular protective effects relevant for vascular dysfunction and prevention of atherosclerosis and thrombosis.

Minimally invasive surgical approach for abdominoscrotal hydrocele treatment: A case report.

Abdominoscrotal hydrocele (ASH) is a rare clinical finding comprising fluid collection between the layers of the tunica vaginalis, extending from the scrotum to the abdominal cavity. At present, there is no unique or recommended management for ASH, and different surgical treatments have been proposed. Despite an open surgical approach being the most common treatment, the use of laparoscopy has also previously been described. The most common intraoperative complication is devascularization of the testis due to damage to the spermatic cord, with consequent orchiectomy. We present a case of ASH treated with minimally invasive surgery, consisting of a right inguinotomy with puncture of the ASH by positioning a mono-J stent avoiding spermatic cord dissection and the risk of testis devascularization. Sclerotization of the hydrocelic sac with iodopovidone through a mono-J stent was performed with healing from ASH and preservation of testicular vascularization. Two months later, magnetic resonance imaging showed the presence of scar tissue replacing the previous ASH cavity.

Validation of a double-color ELISpot assay of IFN-γ and IL-4 production in human peripheral blood mononuclear cells.

The Enzyme-Linked ImmunoSpot (ELISpot) assay detects cytokines secreted during T cell-specific immune responses against pathogens. As this assay has acquired importance in the clinical setting, standard bioanalytical evaluation of this method is required. Here, we describe a formal bioanalytical validation of a double-color ELISpot assay for the evaluation of IFN-γ and IL-4 released by T helper 1 and T helper 2 cells, respectively. As recommended by international guidelines, the parameters assessed were: range and detection limits (limit of detection, LOD; upper and lower limit of quantification, ULOQ and LLOQ), Linearity, Relative Accuracy, Repeatability, Intermediate Precision, Specificity and Robustness. The results obtained in this validation study demonstrate that this assay meets the established acceptability criteria. ELISpot is therefore a reliable technique for measuring T cell-specific immune responses against various antigens of interest.

A novel orf virus vector-based COVID-19 booster vaccine shows cross-neutralizing activity in the absence of anti-vector neutralizing immunity.

Next-generation COVID-19 vaccines are being developed to expand the breadth of coverage against existing and future variants and to extend the duration of protection. Prime-2-CoV_Beta is an orf virus (ORFV) based multi-antigen COVID-19 vaccine that co-expresses Spike (S) and Nucleocapsid (N) antigens. The safety and immunogenicity of Prime-2-CoV_Beta is investigated in a phase 1 first-in-human (FIH) dose-finding trial (ORFEUS study, ClinicalTrials.gov: NCT05367843). Participants of two age groups (18-55 and 65-85 years) who previously completed at least two doses of mRNA vaccines were enrolled and sequentially assigned to different dose groups to receive one intramuscular dose of 3 × 105, 3 × 106, 1.5 × 107, or 3 × 107 plaque-forming units (PFU) of Prime-2-CoV_Beta on day 1 and a second dose on day 29. Here, we report safety and immunogenicity data collected up to 6 months after the first study vaccination. Prime-2-CoV_Beta is safe and well tolerated and elicits immune responses at higher dose levels in participants aged 18-55. A single dose of 3 × 107 PFU boosted binding and cross-neutralizing antibody responses that are maintained through 6 months after the first booster vaccination. Polyfunctional S-specific CD4+ and CD8+ T cell responses are observed after vaccination. No pre-existing or vaccine-induced neutralizing anti-vector antibodies are detected. Our findings highlight the potential of the ORFV vector as a safe platform for future vaccine design, which provides the ability to deliver multiple antigens and allows for repeat immunization.

Safety, reactogenicity, and immunogenicity of ZR-202-CoV and ZR-202a-CoV recombinant vaccines compared with ComirnatyⓇ: A randomized, observer-blind, controlled, phase 1 study.

OBJECTIVES: ZR-202-CoV and ZR-202a-CoV are novel recombinant vaccines containing 25 µg of the prototype (Wuhan strain) or B.1.351 strain (Beta variant) SARS-CoV-2 S-protein expressed in CHO cells, respectively, adjuvanted with Al(OH)3 and CpG-ODN. We assessed their safety and immunogenicity in this Phase I, randomized, observer-blind, controlled study in Mali. DESIGN: Sixty healthy 18-55-year-old adults randomized 1:1:1 received two doses of ZR-202-CoV, ZR-202a-CoV, or ComirnatyⓇ 28 days apart. Primary outcome measures were solicited and unsolicited adverse events (AEs) including AESI (Adverse Events of Special Interest); secondary outcome was immunogenicity measured as SARS-CoV-2 specific neutralizing antibodies. Participants were followed up for 1 year. RESULTS: Injection site pain and headache were the most frequent solicited local and systemic AEs, respectively. No unsolicited AEs or SAEs related to vaccination were reported during the study period. Although most participants had detectable neutralizing antibodies at baseline robust immune responses were observed in all vaccine groups after the first dose with no further increase after the second dose. Cross-neutralizing antibody responses against Beta, Delta, and Omicron BA.5 variants were similar in magnitude after ZR-202-CoV, ZR-202a-CoV and ComirnatyⓇ. CONCLUSIONS: Similar reactogenicity and immunogenicity profiles of ZR-202-CoV, ZR-202a-CoV and ComirnatyⓇ support further clinical investigation in a wider population.

A multiantigenic Orf virus-based vaccine efficiently protects hamsters and nonhuman primates against SARS-CoV-2.

Among the common strategies to design next-generation COVID-19 vaccines is broadening the antigenic repertoire thereby aiming to increase efficacy against emerging variants of concern (VoC). This study describes a new Orf virus-based vector (ORFV) platform to design a multiantigenic vaccine targeting SARS-CoV-2 spike and nucleocapsid antigens. Vaccine candidates were engineered, either expressing spike protein (ORFV-S) alone or co-expressing nucleocapsid protein (ORFV-S/N). Mono- and multiantigenic vaccines elicited comparable levels of spike-specific antibodies and virus neutralization in mice. Results from a SARS-CoV-2 challenge model in hamsters suggest cross-protective properties of the multiantigenic vaccine against VoC, indicating improved viral clearance with ORFV-S/N, as compared to equal doses of ORFV-S. In a nonhuman primate challenge model, vaccination with the ORFV-S/N vaccine resulted in long-term protection against SARS-CoV-2 infection. These results demonstrate the potential of the ORFV platform for prophylactic vaccination and represent a preclinical development program supporting first-in-man studies with the multiantigenic ORFV vaccine.

PKCε activation promotes FGF-2 exocytosis and induces endothelial cell proliferation and sprouting.

Protein kinase C epsilon (PKCε) activation controls fibroblast growth factor-2 (FGF-2) angiogenic signaling. Here, we examined the effect of activating PKCε on FGF-2 dependent vascular growth and endothelial activation. ψεRACK, a selective PKCε agonist induces pro-angiogenic responses in endothelial cells, including formation of capillary like structures and cell growth. These effects are mediated by FGF-2 export to the cell membrane, as documented by biotinylation and immunofluorescence, and FGF-2/FGFR1 signaling activation, as attested by ERK1/2-STAT-3 phosphorylation and de novo FGF-2 synthesis. Similarly, vascular endothelial growth factor (VEGF) activates PKCε in endothelial cells, and promotes FGF-2 export and FGF-2/FGFR1 signaling activation. ψεRACK fails to elicit responses in FGF-2(-/-) endothelial cells, and in cells pretreated with methylamine (MeNH2), an exocytosis inhibitor, indicating that both intracellular FGF-2 and its export toward the membrane are required for the ψεRACK activity. In vivo ψεRACK does not induce angiogenesis in the rabbit cornea. However, ψεRACK promotes VEGF angiogenic responses, an effect sustained by endothelial FGF-2 release and synthesis, since anti-FGF-2 antibody strongly attenuates VEGF responses. The results demonstrate that PKCε stimulation promotes angiogenesis and modulates VEGF activity, by inducing FGF-2 release and autocrine signaling.