作者: Benson Ogunjimi ; Hilde Jansens ; Philippe Beutels ; Ronald Malfait ; Holden T. Maecker ; Pierre Van Damme ; Evelien Smits ; Steven Heynderickx ; Jose Ramet ; Johan Van den Bergh ; Joke Bilcke ; Nathalie Cools

ABSTRACTReexposure to viruses is assumed to strengthen humoral and cellular immunity via the secondary immune response. We studied the effects of frequent exposure to viral infectious challenges on immunity. Furthermore, we assessed whether repetitive exposures to varicella-zoster virus (VZV) elicited persistently high immune responses. Blood samples from 11 pediatricians and matched controls were assessed at 3 time points and 1 time point, respectively. Besides the assessment of general immunity by means of measuring T-cell subset percentages, antibody titers and gamma interferon (IFN-γ)/interleukin 2 (IL-2)-producing T-cell percentages against adenovirus type 5 (AdV-5), cytomegalovirus (CMV), tetanus toxin (TT), and VZV were determined. Pediatricians had lower levels of circulating CD4+-naive T cells and showed boosting of CD8+effector memory T cells. Although no effect on humoral immunity was seen, repetitive exposures to VZV induced persistently higher percentages of IFN-γ-positive T cells against all VZV antigens tested (VZV glycoprotein E [gE], VZV intermediate-early protein 62 [IE62], and VZV IE63) than in controls. T cells directed against latency-associated VZV IE63 benefitted the most from natural exogenous boosting. Although no differences in cellular or humoral immunity were found between the pediatricians and controls for AdV-5 or TT, we did find larger immune responses against CMV antigens in pediatricians. Despite the high infectious burden, we detected a robust and diverse immune system in pediatricians. Repetitive exposures to VZV have been shown to induce a stable increased level of VZV-specific cellular but not humoral immunity. Based on our observations, VZV IE63 can be considered a candidate for a zoster vaccine.

2011-01-01·Clinical laboratory4区 · 医学

Inactivation of herpes simplex virus type 1 & adenovirus type 5 by direct electric current at a biocompatible level in vitro.

4区 · 医学

Article

作者: Bamdad, Taravat ; Roohandeh, Majid

BACKGROUNDIn vitro studies were conducted to quantify the effectiveness of low-level direct electric current (DC) on infectivity of Herpes Simplex Virus type 1 (HSV-1), Adenovirus type 5 (AdV-5), and on viability of Vero cells.METHODSBoth viruses and Vero cells were exposed to DC by using platinum electrodes connected to a DC source, then the viral infectivity and cell viability were assessed by plaque and MTT assay, respectively.RESULTSThe results showed that both viruses were inactivated completely by 200 microA DC in 10 minutes (current density = 20 microA/mm2) while this amount of DC had no significant changes on the viability of Vero cells (viability > 90 %). Inactivation degree of HSV-1 and AdV-5 was 5 and 4 log per mL, respectively. Further study is required to investigate the mechanism of inactivation by this method.CONCLUSIONSDC at a biocompatible level showed the competency to inactivate the viruses in the solution completely. So it is a useful tool for designing a noninvasive method for decontamination of biological or synthetic fluids. This method or derivation can be considered as an easy, fast, and economical method for fluid decontamination.

2006-01-01·Biological and Pharmaceutical Bulletin4区 · 医学

In Vitro Antiviral Activity of Marine Sponges Collected Off Brazilian Coast

4区 · 医学

Article

作者: Simões, Cláudia Maria Oliveira ; Henriques, Amélia Terezinha ; Lerner, Clea ; Kratz, Jadel Muller ; Farias, Fabiane Maria ; dos Santos, Josivete ; Leonel, Rosa Maria ; Barardi, Célia Regina Monte ; Mothes, Beatriz ; da Silva, Alexandre Cordeiro

This paper describes the in vitro antiviral evaluation of 27 different marine sponges (Porifera) collected off Brazilian coastline in the search for novel drug leads. With these sponges aqueous and organic extracts were prepared and tested for anti-herpetic (HSV-1, KOS strain), anti-adenovirus (human AdV serotype 5) and anti-rotavirus (simian RV SA11) activities. The evaluation of the cytotoxicity and potential antiviral activity of these extracts were performed by using MTT assay. Results were expressed as 50% cytotoxicity (CC50) and 50% effective (EC50) concentrations, respectively, in order to calculate the selectivity indices (SI=CC50/EC50) of each extract. From the 40 sponge extracts tested, 17 extracts showed antiviral action in different degrees. The results concerning the antiviral activity were obtained by using three different strategies: (1) simultaneous assay, when sponge extracts were added to the cells at the same time of the viruses; (2) pre treatment assay, when sponge extracts were added to the cells 15 h prior to the viruses infection; and (3) post treatment assay, when the viruses were added to the cells and remained during 2 h prior to the addition of sponge extracts. The antiviral assays with HSV-1/KOS and AdV-5 showed more promising results when the pre treatment test was employed. In relation to the RV-SA11 virus, only the simultaneous assay showed antiviral activity. The extracts presenting the most promising results were the aqueous extracts of Cliona sp., Agelas sp.2, Tethya sp., Axinella aff corrugata, Polymastia janeirensis and Protosuberites sp., and these extracts deserve special attention in further studies.

100 项与 Adv-005 相关的药物交易

登录后查看更多信息