Age related changes in T cell mediated immune response and effector memory to Respiratory Syncytial Virus (RSV) in healthy subjects

Abstract Respiratory syncytial virus (RSV) is the major pathogen causing respiratory disease in young infants and it is an important cause of serious illness in the elderly since the infection provides limited immune protection against reinfection. In order to explain this phenomenon, we investigated whether healthy adults of different age (20-40; 41-60 and > 60 years), have differences in central and effector memory, RSV-specific CD8+ T cell memory immune response and regulatory T cell expression status. In the peripheral blood of these donors, we were unable to detect any age related difference in term of central (CD45RA-CCR7+) and effector (CD45RA-CCR7-) memory T cell frequency. On the contrary, we found a significant increase in immunosuppressive regulatory (CD4+25+FoxP3+) T cells (Treg) in the elderly. An immunocytofluorimetric RSV pentamer analysis performed on these donors' peripheral blood mononuclear cells (PBMCs), in vitro sensitized against RSV antigen, revealed a marked decline in long-lasting RSV specific CD8+ memory T cell precursors expressing interleukin 7 receptor α (IL-7Rα), in the elderly. This effect was paralleled by a progressive switch from a Th1 (IFN-γ and TNF-α) to a Th2 (IL-10) functional phenotype. On the contrary, an increase in Treg was observed with aging. The finding of Treg over-expression status, a prominent Th2 response and an inefficient RSV-specific effector memory CD8+ T cell expansion in older donors could explain the poor protection against RSV reinfection and the increased risk to develop an RSV-related severe illness in this population. Our finding also lays the basis for new therapeutic perspectives that could limit or prevent severe RSV infection in elderly.</p

Additive Manufacturing Techniques for the Reconstruction of 3D Fetal Faces

This paper deals with additive manufacturing techniques for the creation of 3D fetal face models starting from routine 3D ultrasound data. In particular, two distinct themes are addressed. First, a method for processing and building 3D models based on the use of medical image processing techniques is proposed. Second, the preliminary results of a questionnaire distributed to future parents consider the use of these reconstructions both from an emotional and an affective point of view. In particular, the study focuses on the enhancement of the perception of maternity or paternity and the improvement in the relationship between parents and physicians in case of fetal malformations, in particular facial or cleft lip diseases

Evaluation of a novel immunogenic vaccine platform based on a genome replication-deficient Sendai vector.

We developed a novel vaccine platform based on a paramyxoviral, genome replication-deficient Sendaivirus vector that can express heterologous genes inserted into the genome. To validate the novel approachin vivo, we generated a combined vaccine candidate against human respiratory syncytial virus (RSV)and human parainfluenza virus type 3 (PIV3). The present study compares two different methods ofdisplaying heterologous antigens: (i) the RSV fusion (F) protein, encoded as a secretable version in anadditional transcription unit, serves as an antigen only after being expressed in infected cells; (ii) PIV3fusion (F) and hemagglutinin-neuraminidase (HN) genes, replacing Sendai counterparts in the vectorgenome, are also expressed as structural components on the surface of vaccine particles. The efficacyof this prototype vaccine was assessed in a mouse model after mucosal administration. The vaccinecandidate was able to elicit specific mucosal, humoral and T cell-mediated immune responses againstRSV and PIV3. However, PIV3 antigen display on the vaccine particles’ surface induced higher antibodytiters than the RSV antigen, being expressed only after cell infection. Consequently, this construct inducedan adequate neutralizing antibody response only to PIV3. Finally, replicating virus particles were notdetected in the lungs of immunized mice, confirming the genome stability and replication deficiencyof this vaccine vector in vivo. Both factors can contribute substantially to the safety profile of vaccinecandidates. In conclusion, this replication-deficient Sendai vector represents an efficient platform thatcan be used for vaccine developments against various viral pathogens

Phospholipid scramblase 1 is involved in immunogenic cell death and contributes to dendritic cell–based vaccine efficiency to elicit antitumor immune response in vitro

Background aims: Whole tumor cell lysates (TCLs) obtained from cancer cells previously killed by treatments able to promote immunogenic cell death (ICD) can be efficiently used as a source of tumor-associated antigens for the development of highly efficient dendritic cell (DC)-based vaccines. Herein, the potential role of the interferon (IFN)-inducible protein phospholipid scramblase 1 (PLSCR1) in influencing immunogenic features of dying cancer cells and in enhancing DC-based vaccine efficiency was investigated. Methods: PLSCR1 expression was evaluated in different mantle-cell lymphoma (MCL) cell lines following ICD induction by 9-cis-retinoic acid (RA)/IFN-α combination, and commercial kinase inhibitor was used to identify the signaling pathway involved in its upregulation. A Mino cell line ectopically expressing PLSCR1 was generated to investigate the potential involvement of this protein in modulating ICD features. Whole TCLs obtained from Mino overexpressing PLSCR1 were used for DC loading, and loaded DCs were employed for generation of tumor antigen-specific cytotoxic T lymphocytes. Results: The ICD inducer RA/IFN-α combination promoted PLSCR1 expression through STAT1 activation. PLSCR1 upregulation favored pro-apoptotic effects of RA/IFN-α treatment and enhanced the exposure of calreticulin on cell surface. Moreover, DCs loaded with TCLs obtained from Mino ectopically expressing PLSCR1 elicited in vitro greater T-cell–mediated antitumor responses compared with DCs loaded with TCLs derived from Mino infected with empty vector or the parental cell line. Conversely, PLSCR1 knock-down inhibited the stimulating activity of DCs loaded with RA/IFN-α–treated TCLs to elicit cyclin D1 peptide-specific cytotoxic T lymphocytes. Conclusions: Our results indicate that PLSCR1 improved ICD-associated calreticulin exposure induced by RA/IFN-α and was clearly involved in DC-based vaccine efficiency as well, suggesting a potential contribution in the control of pathways associated to DC activation, possibly including those involved in antigen uptake and concomitant antitumor immune response activation.Fil: Montico, Barbara. Centro Di Riferimento Oncologico Di Aviano; Italia. Istituti di Ricovero e Cura a Carattere Scientifico; ItaliaFil: Nigro, Annunziata. Universita di Salerno; ItaliaFil: Lamberti, María Julia. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Biotecnologia Ambiental y Salud. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Biotecnologia Ambiental y Salud.; Argentina. Universidad Nacional de Río Cuarto; ArgentinaFil: Martorelli, Debora. Centro Di Riferimento Oncologico Di Aviano; Italia. Istituti di Ricovero e Cura a Carattere Scientifico; ItaliaFil: Mastorci, Katy. Centro Di Riferimento Oncologico Di Aviano; Italia. Istituti di Ricovero e Cura a Carattere Scientifico; ItaliaFil: Ravo, Maria. Genomix 4 Life; ItaliaFil: Giurato, Giorgio. Universita di Salerno; ItaliaFil: Steffan, Agostino. Centro Di Riferimento Oncologico Di Aviano; Italia. Istituti di Ricovero e Cura a Carattere Scientifico; ItaliaFil: Dolcetti, Riccardo. University of Melbourne; AustraliaFil: Casolaro, Vincenzo. Universita di Salerno; ItaliaFil: Dal Col, Jessica. Universita di Salerno; Itali

Oropharyngeal meningococcal carriage in children and adolescents, a single center study in Buenos Aires, Argentina.

BackgroundNeisseria meningitidis (Nm) pharyngeal carriage is a necessary condition for invasive disease. We present the first carriage study in children in Buenos Aires, Argentina, considering 2017 as a transition year. Aims: to assess the rate of Nm carriage, to determine genogroup, clonal complex and outer membrane protein distribution, to determine carriage risk factors by age.MethodsCross-sectional study including children 1-17 yrs, at Ricardo Gutiérrez Children's Hospital in Buenos Aires 2017. Oro-pharyngeal swabs were taken and cultured within a short time after collection. Genogroup was determined by PCR and clonal complex by MLST. Categorical variables were analyzed.ResultsA total of 1,751 children were included. Group 1: 943 children 1-9 yrs, 38 Nm were isolated; overall carriage 4.0%. Genogroup distribution: B 26.3%, W 5.3%, Y 2.6%, Z 5.3%, other groups 7.9% and capsule null (cnl) 52.6%. Participating in extracurricular activities was the only independent predictor of Nm carriage. Group 2: 808 children 10-17 yrs, 76 Nm were isolated; overall carriage 9.4%. Genogroup distribution: B 19.7%, C 5.3%, W 7.9%, Y 9.2%, Z 5.3%, other groups 7.9% and cnl 44.7%. Independent predictors of carriage: attending pubs/night clubs and passive smoking (adjusted OR: 0.55, 95%CI = 0.32-0.93; p = 0.025).ConclusionsOverall carriage was higher in 10-17 yrs. The isolates presenting the cnl locus were prevalent in both age groups and genogroup B was the second most frequent

Native CB1 receptor affinity, intrinsic activity and accumbens shell dopamine stimulant properties of third generation SPICE/K2 cannabinoids: BB-22, 5F-PB-22, 5F-AKB-48 and STS-135

In order to investigate the in vivo dopamine (DA) stimulant properties of selected 3rd generation Spice/K2 cannabinoids, BB-22, 5F-PB-22, 5F-AKB-48 and STS-135, their in vitro affinity and agonist potency at native rat and mice CB1 receptors was studied. The compounds bind with high affinity to CB1 receptors in rat cerebral cortex homogenates and stimulate CB1-induced [(35)S]GTPγS binding with high potency and efficacy. BB-22 and 5F-PB-22 showed the lowest Ki of binding to CB1 receptors (0.11 and 0.13 nM), i.e., 30 and 26 times lower respectively than that of JWH-018 (3.38 nM), and a potency (EC50, 2.9 and 3.7 nM, respectively) and efficacy (Emax, 217% and 203%, respectively) as CB1 agonists higher than JWH-018 (EC50, 20.2 nM; Emax, 163%). 5F-AKB-48 and STS-135 had higher Ki for CB1 binding, higher EC50 and lower Emax as CB1 agonists than BB-22 and 5F-PB-22 but still comparatively more favourable than JWH-018. The agonist properties of all the compounds were abolished or drastically reduced by the CB1 antagonist/inverse agonist AM251 (0.1 μM). No activation of G-protein was observed in CB1-KO mice. BB-22 (0.003-0.01 mg/kg i.v.) increased dialysate DA in the accumbens shell but not in the core or in the medial prefrontal cortex, with a bell shaped dose-response curve and an effect at 0.01 mg/kg and a biphasic time-course. Systemic AM251 (1.0 mg/kg i.p.) completely prevented the stimulant effect of BB-22 on dialysate DA in the NAc shell. All the other compounds increased dialysate DA in the NAc shell at doses consistent with their in vitro affinity for CB1 receptors (5F-PB-22, 0.01 mg/kg; 5F-AKB-48, 0.1 mg/kg; STS-135, 0.15 mg/kg i.v.). 3rd generation cannabinoids can be even more potent and super-high CB1 receptor agonists compared to JWH-018. Future research will try to establish if these properties can explain the high toxicity and lethality associated with these compounds

Detection of HIV-1 matrix protein P17 quasispecies variants in plasma of chronic HIV-1-infected patients by ultra-deep pyrosequencing

Background:The HIV-1 matrix protein p17 (p17MA) is a pleiotropic protein that plays a key role in the HIV-1 life cycle. It has been long believed to have a highly conserved primary amino acid sequence and a well-preserved structural integrity to avoid severe fitness consequences. However, recent data revealed that the carboxy (COOH)-terminus of p17MA possesses high levels of predicted intrinsic disorder, which would subtend to at least partially unfolded status of this region. This finding pointed to the need of investigating p17MA heterogeneity.Methods:The degree of intrapatient variations in the p17MA primary sequence was assessed on plasma viral RNA by using ultra-deep pyrosequencing.Results:Data obtained support a complex nature of p17MA quasispecies, with variants present at variable frequency virtually in all patients. Clusters of mutations were scattered along the entire sequence of the viral protein, but they were more frequently detected within the COOH-terminal region of p17MA. Moreover, deletions and insertions also occurred in a restricted area of the COOH-terminal region.Conclusions:On the whole, our data show that the intrapatient level of sequence diversity in the p17MA is much higher than predicted before. Our results pave the way for further studies aimed at unraveling possible correlations between the presence of distinct p17MA variants and peculiar clinical evolutions of HIV-1 disease. The presence of p17MA quasispecies diversity may offer new tools to improve our understanding of the viral adaptation during the natural history of HIV-1 infection