Saliva and Plasma Neutralizing Activity Induced by the Administration of a Third bnt162b2 Vaccine Dose.

The BNT162b2 vaccine induces neutralizing activity (NA) in serum, but no data are available on whether a third-dose activates specific-immunity within the oral mucosa, representing the primary route of viral-entry. To carefully address this issue, we investigated if such immunity is boosted by SARS-CoV-2-infection; how long it is maintained over-time; and if it protects against the SARS-CoV-2 lineage B.1 (EU) and the emerging Delta and Omicron variants. NA was measured in plasma and saliva samples from: uninfected SARS-CoV-2-Vaccinated (SV), subjects infected prior to vaccination (SIV), and subjects who were infected after the second (SIV2) or the third (SIV3) vaccine dose. Samples were collected immediately before (T0), 15 days (T1), and 90 days (T2) post third-dose administration (SV and SIV), or 15 days post-infection (SIV2 and SIV3). In all the enrolled groups, NA in plasma and saliva: (i) was higher against EU compared to the other variants at all time-points (SV: T0 and T1, EU vs. both Delta and Omicron p < 0.001; T2 p < 0.01) (SIV: T0, EU vs. Delta p < 0.05; EU vs. Omi p < 0.01; T1 and T2 EU vs. Delta p < 0.01; EU vs. Omi p < 0.001); (ii) was boosted by the administration of the third dose; iii) declined over-time, albeit being detectable in almost all subjects at T2. The monitoring of NA over time will be important in clarifying if different NA levels may influence either acquisition or course of infection to properly plan the timing of a fourth vaccine dose administration.

Oligomeric α-Syn and SNARE complex proteins in peripheral extracellular vesicles of neural origin are biomarkers for Parkinson's disease.

Blood-based biomarkers are needed to be used as easy, reproducible, and non-invasive tools for the diagnosis and prognosis of chronic neurodegenerative disorders including Parkinson's Disease (PD). In PD, aggregated toxic forms of α-Synuclein (α-Syn) accumulate within neurons in the brain and cause neurodegeneration; α-Syn interaction with SNARE proteins also results in synaptic disfunction. We isolated neural derived extravesicles (NDEs) from peripheral blood of 32 PD patients and 40 healthy controls (HC) and measured the concentrations of oligomeric α-Syn and of the presinaptic SNARE complex proteins: STX-1A, VAMP-2 and SNAP-25. Oligomeric α-Syn was significantly augmented whereas STX-1A and VAMP-2 were significantly reduced in NDEs of PD patients compared to HC (p < 0.001 in all cases). ROC curve analyses confirmed the discriminatory ability of NDEs oligomeric α-Syn, STX-1A and VAMP-2 levels to distinguish between PD patients and HC. Oligomeric α-Syn NDEs concentration also positively correlated with disease duration and severity of PD. These results are promising and confirm that NDEs cargoes likely reflect core pathogenic intracellular processes in their originating brain cells and could serve as novel easily accessible bio-markers. Further studies are needed to confirm results and eventually for testing rehabilitation programs and drug treatments effects.

Evaluation of the immune benefits of two probiotic strains Bifidobacterium animalis ssp. lactis, BB-12® and Lactobacillus paracasei ssp. paracasei, L. casei 431® in an influenza vaccination model: a randomised, double-blind, placebo-controlled study.

The present study investigated the ability of Bifidobacterium animalis ssp. lactis (BB-12®) and Lactobacillus paracasei ssp. paracasei (L. casei 431®) to modulate the immune system using a vaccination model in healthy subjects. A randomised, double-blind, placebo-controlled, parallel-group study was conducted in 211 subjects (56 % females, mean age 33·2 (sd 13·1) years). Subjects consumed a minimum of 109 colony-forming units of BB-12® (capsule) or L. casei 431® (dairy drink) or a matching placebo once daily for 6 weeks. After 2 weeks, a seasonal influenza vaccination was given. Plasma and saliva samples were collected at baseline and after 6 weeks for the analysis of antibodies, cytokines and innate immune parameters. Changes from baseline in vaccine-specific plasma IgG, IgG1 and IgG3 were significantly greater in both probiotic groups v. the corresponding placebo group (L. casei 431®, P = 0·01 for IgG; P < 0·001 for remaining comparisons). The number of subjects obtaining a substantial increase in specific IgG (defined as ≥ 2-fold above baseline) was significantly greater in both probiotic groups v. placebo (BB-12®, P < 0·001 for IgG, IgG1 and IgG3; L. casei 431®, P < 0·001 for IgG1 and IgG3). Significantly greater mean fold increases for vaccine-specific secretory IgA in saliva were observed in both probiotic groups v. placebo (BB-12®, P = 0·017; L. casei 431®, P = 0·035). Similar results were observed for total antibody concentrations. No differences were found for plasma cytokines or innate immune parameters. Data herein show that supplementation with BB-12® or L. casei 431® may be an effective means to improve immune function by augmenting systemic and mucosal immune responses to challenge.

Natural SARS-CoV-2 Infection Affects Neutralizing Activity in Saliva of Vaccinees.

Background: SARS-CoV-2 transmission mainly occurs through exposure of the upper airway mucosa to infected secretions such as saliva, which are excreted by an infected person. Thus, oral mucosal immunity plays a central role in the prevention of and early defense against SARS-CoV-2 infection. Although virus-specific antibody response has been extensively investigated in blood samples of SARS-CoV-2-infected patients and vaccinees, local humoral immunity in the oral cavity and its relationship to systemic antibody levels needs to be further addressed. Material and Methods: We fine-tuned a virus neutralization assay (vNTA) to measure the neutralizing activity (NA) of plasma and saliva samples from 20 SARS-CoV-2-infected (SI), 40 SARS-CoV-2-vaccinated (SV), and 28 SARS-CoV-2-vaccinated subjects with a history of infection (SIV) using the "wild type" SARS-CoV-2 lineage B.1 (EU) and the Delta (B.1.617.2) strains. To validate the vNTA results, the presence of neutralizing antibodies (NAbs) to the spike receptor binding domain (RBD) was evaluated with an ELISA assay. Results: NA to SARS-CoV-2 lineage B.1 (EU) was present in plasma samples from all the tested subjects, with higher titers in SIV compared to both SI and SV. Conversely, NA was detected in saliva samples from 10.3% SV, 45% SI, and 92.6% SIV, with significantly lower titers in SV compared to both SI and SIV. The detection of NAbs in saliva reflected its reduced NA in SV. Discussion: The difference in NA of plasma vs. saliva was confirmed in a vNTA where the SARS-CoV-2 B.1 and Delta strains were tested head-to-head, which also revealed a reduced NA of both specimens compared to the B.1 variant. Conclusions: The administration of SARS-CoV-2 vaccines was associated with limited virus NA in the oral cavity, as measured in saliva and in comparison to plasma. This difference was more evident in vaccinees without a history of SARS-CoV-2 infection, possibly highlighting the importance of local exposure at the site of virus acquisition to effectively prevent the infection and block its spread. Nevertheless, the presence of immune escape mutations as possibly represented by the SARS-CoV-2 Delta variant negatively affects both local and systemic efficacy of NA associated with vaccination.

Intrafamiliar transmission of Kaposi's sarcoma-associated herpesvirus and seronegative infection in family members of classic Kaposi's sarcoma patients.

The link between Kaposi's sarcoma-associated herpesvirus (KSHV or human herpesvirus 8) and Kaposi's sarcoma has been proven, but the transmission routes, especially in the heterosexual population, are not yet completely understood. To assess the intrafamilial patterns of transmission among first-degree relatives of Italian classic Kaposi's sarcoma (cKS) patients, KSHV seroprevalence and the presence of viral DNA in blood and saliva were evaluated in 18 families (32 cKS patients and 35 family members), comparing the results with those obtained in 200 elderly healthy controls without known exposure to KSHV. The KSHV genotype of variable region VR1 of the hypervariable ORF K1 gene was subsequently analysed in all KSHV-positive samples. The results showed that KSHV infection was significantly higher in relatives of cKS patients (11/35 cases) than in healthy controls (17/200 cases; P=0.001). The 11 infected relatives included spouses (n=3), siblings (n=2) and offspring (n=6) of the cKS patients; the same KSHV genotype was shared within the same family in the majority of cases (85%), indicating the presence of person-to-person transmission within families. Viral DNA was mostly observed in the saliva of infected relatives (45.4%); detection of DNA in blood was less frequent (27.3%). Notably, KSHV DNA was present in saliva and/or blood of three KSHV-infected relatives with indeterminate or negative serostatus. Thus, the risk of KSHV infection is greatly enhanced within families of cKS patients, where close contacts (horizontal and/or sexual) can contribute to the spread of KSHV.

Treatment of periodontal disease results in improvements in endothelial dysfunction and reduction of the carotid intima-media thickness.

Several cohort studies reported a relation of cardiovascular events and periodontal disease. In particular, Porphyromonas gingivalis is associated with the development of atherosclerotic plaques. We verified in a longitudinal study whether inflammation biomarkers, endothelial adhesion molecules, leukocyte activation markers, and intima-media thickness could be beneficially modified by periodontal treatment alone. Thirty-five otherwise healthy individuals affected by mild to moderate parodontopathy were enrolled in the study. Echo-Doppler cardiography of the carotid artery, fluorescence-activated cell sorting analyses on lymphocytes and monocytes, and plasma inflammatory indices were evaluated at baseline and at multiple time points after the periodontal treatment. Results showed that inflammation biomarkers were abnormally increased at baseline. Periodontal treatment resulted in a significant reduction of the total oral bacterial load that was associated with a significant amelioration of inflammation biomarkers and of adhesion and activation proteins. Notably, intima-media thickness was significantly diminished after treatment. Inflammatory alterations associated with the genesis of atherosclerotic plaques are detected in otherwise healthy individuals affected by parodontopathy and are positively influenced by periodontal treatment. Reduction of oral bacterial load results in a modification of an anatomical parameter directly responsible for atherosclerosis. These results shed light on the pathogenesis of atherosclerosis and could have practical implications for public health.

HHV8 a subtype is associated with rapidly evolving classic Kaposi's sarcoma.

The link between human herpesvirus 8 (KSHV) and Kaposi's sarcoma (KS) has been proven, but many important aspects including risk factors, genetic predisposition to tumor development, transmission of KSHV, and the pathogenic potential of different genotypes remain to be elucidated. Possible associations between clinical parameters and antibody levels, viral load fluctuations, and viral genotype were analyzed by quantitative real-time PCR, an in-house developed IFA assay, and sequence analysis of ORF K1-VR1 in blood, serum and saliva of 38 subjects with classic KS (cKS). KSHV lytic antibodies were significantly increased in stage IV compared to stage I and II patients (p = 0.006 and p = 0.041, respectively). KSHV blood, serum, and saliva viral load was comparable in all stages. The highest viral loads were detected in saliva, and they decreased in stages III-IV compared to stages I-II patients. Higher concentrations of lytic antibodies and higher viral loads were observed in fast progressing cKS patients, in whom KSHV detection from blood was also more frequent. Type A KSHV strain was almost exclusively present in rapid progressors (12/17 cases), while C type was mainly present in slow progressing patients (6/7 cases). Finally, detection of type A KSHV strain associated with higher blood viral loads. KSHV lytic antibody levels and viral load can be used to monitor clinical evolution of cKS. Infection supported by KSHV A subtype is associated with more rapid progressive disease. Careful monitoring and aggressive therapeutic protocols should be considered in patients with KSHV A-supported infection.

Linear biocompatible glyco-polyamidoamines as dual action mode virus infection inhibitors with potential as broad-spectrum microbicides for sexually transmitted diseases.

The initial steps of viral infections are mediated by interactions between viral proteins and cellular receptors. Blocking the latter with high-affinity ligands may inhibit infection. DC-SIGN, a C-type lectin receptor expressed by immature dendritic cells and macrophages, mediates human immunodeficiency virus (HIV) infection by recognizing mannose clusters on the HIV-1 gp120 envelope glycoprotein. Mannosylated glycodendrimers act as HIV entry inhibitors thanks to their ability to block this receptor. Previously, an amphoteric, but prevailingly cationic polyamidoamine named AGMA1 proved effective as infection inhibitor for several heparan sulfate proteoglycan-dependent viruses, such as human papilloma virus HPV-16 and herpes simplex virus HSV-2. An amphoteric, but prevailingly anionic PAA named ISA23 proved inactive. It was speculated that the substitution of mannosylated units for a limited percentage of AGMA1 repeating units, while imparting anti-HIV activity, would preserve the fundamentals of its HPV-16 and HSV-2 infection inhibitory activity. In this work, four biocompatible linear PAAs carrying different amounts of mannosyl-triazolyl pendants, Man-ISA7, Man-ISA14, Man-AGMA6.5 and Man-AGMA14.5, were prepared by reaction of 2-(azidoethyl)-α-D-mannopyranoside and differently propargyl-substituted AGMA1 and ISA23. All mannosylated PAAs inhibited HIV infection. Both Man-AGMA6.5 and Man-AGMA14.5 maintained the HPV-16 and HSV-2 activity of the parent polymer, proving broad-spectrum, dual action mode virus infection inhibitors.

Hemodynamic and autonomic adjustments to real life stress conditions in humans.

Psychological stress represents a risk factor for hypertension, but mechanisms are not known in detail. In this investigation we tested the hypothesis that real-life stress conditions produce changes in autonomic cardiac and vascular regulation that might differ in magnitude. University students, a well-established model of mild real-life stress, were examined shortly before a university examination, and a second time 3 months afterward, during holiday. Autonomic cardiovascular regulation was assessed by a noninvasive approach, based on autoregressive analysis of RR interval variability (V) and of systolic arterial pressure (SAP) V. The overall level of stress in the two sessions was gauged from the elevated salivary cortisol (5.6+/-0.5 versus 2.4+/-0.2 ng/mL, P<0.05) and altered cytokine profile (P<0.05). During the stress day, the RR interval was reduced and arterial pressure increased significantly; simultaneously, the normalized low frequency component of RRV (a marker of sympathetic modulation of the sinoatrial node) was increased and the index alpha (a measure of baroreflex gain) reduced. Concomitantly, the autonomic response to the sympathetic excitation produced by standing was altered: cardiac response was impaired and vascular responsiveness increased. Markers of autonomic regulation of the sinoatrial node correlated significantly with cortisol levels, both at rest and also considering standing induced changes, suggesting a gradual range of effects. The data support the concept that mild real-life stress increases arterial pressure and impairs cardiovascular homeostasis. These changes, assessable with spectral analysis of cardiovascular variability, might contribute, in susceptible individuals, to the link between psychological stress and increased cardiovascular risk of hypertension.

Cross-clade HIV-1-specific neutralizing IgA in mucosal and systemic compartments of HIV-1-exposed, persistently seronegative subjects.

There is an urgent need for a universally effective HIV-1 vaccine, but whether a vaccine will be able to protect against HIV-1 of different clades is a significant concern. IgA from HIV-1-exposed, persistently seronegative (HEPS) subjects has been shown to neutralize HIV-1 and to block epithelial HIV-1 transcytosis, and it may target novel HIV-1 epitopes. We have tested the ability of plasma and mucosal IgA purified from HEPS subjects to neutralize HIV-1 primary isolates of different viral clades and phenotypes. IgA from two groups of HEPS subjects was tested: sex workers from Nairobi, Kenya, where clades A and D predominate, and the heterosexual partners of individuals infected by clade B virus. HIV-1-infected and low-risk uninfected individuals were included as controls. IgA purified from the blood, genital tract, and saliva of most HEPS sex workers demonstrated significant cross-clade HIV-1 neutralization, whereas a more clade-restricted pattern of neutralization was found in partners of clade B-infected individuals. IgA purified from HIV-1-infected individuals also mediated cross-clade neutralization, whereas IgA from uninfected controls lacked neutralizing activity. In conclusion, mucosal and plasma IgA from HEPS subjects neutralizes HIV-1 of different clades. This ability to induce HIV-1-specific systemic and mucosal IgA may be an important feature of an effective prophylactic HIV-1 vaccine.