Safety and immune responses after intradermal application of Porcilis PRRS in either the neck or the perianal region.

The objective of the present study was to assess safety and immune responses in gilts after intradermal application of Porcilis® PRRS in two different application sites under field conditions. Forty-four gilts were allocated to one of three groups: Gilts of group 1 (n = 10) served as non-vaccinated controls, gilts of group 2 (n = 17) were vaccinated intradermally in the neck and gilts of group 3 (n = 17) received an intradermal vaccination in the perianal region. Clinical observations, local injection site reactions and histopathologic examination of the injection site were used for safety assessments. Frequency and degree of clinical signs were not significantly different between all three groups. Minor local reactions for both vaccination groups were observed; however, at 6, 7, 8, 9 and 15 days post-vaccination (dpv), the mean injection site reaction score was significantly lower in pigs vaccinated in the perianal region. In histopathologic examination, an extended inflammatory dimension was observed more frequently in pigs vaccinated in the neck. Blood samples were analyzed to quantify the post-vaccination humoral (ELISA and virus neutralization test) and cellular (IFN-γ ELISPOT) immune responses. PRRSV-specific antibodies were present in the serum of all vaccinated animals from 14 dpv onwards, whereas all control pigs remained negative throughout the study. Neutralizing antibody titers were significantly higher in pigs vaccinated in the perianal region at 28 dpv. At 14, 21 and 28 dpv, PRRSV-specific IFN-γ secreting cells were significantly increased in both vaccination groups compared to non-vaccinated gilts. Analysis of mean numbers of PRRSV-specific IFN-γ secreting cells did not result in statistically significant differences between both vaccination groups. The results of this study indicate that the perianal region is a safe alternative application site for intradermal vaccination of gilts with Porcilis PRRS. Furthermore, the intradermal application of Porcilis PRRS induced humoral and cellular immune responses independent of the administration site.

Antiviral activity of aspirin against RNA viruses of the respiratory tract-an in vitro study.

AIM: Aspirin (acetylsalicylic acid) has been used for more than 115 years in medicine. Research exists to show that aspirin has antiviral effects in vitro, for example, by blocking influenza virus propagation via NF-κB inhibition when used at high concentrations and short-term incubation steps. The aim of this study was to confirm the antiviral activity of aspirin against influenza virus and further elucidate the activity of aspirin against other respiratory viruses. METHODS: Tests to detect antiviral activity were performed using plaque-reduction assays. Aspirin was administered to the virus-infected cell cultures one hour after infection. Prior to these assays, the non-cytotoxic concentrations of aspirin on cells used for propagation of the respective viruses were determined. RESULTS: Aspirin was found to be highly effective against influenza A H1N1 virus. The antiviral activity against further respiratory RNA viruses was less distinct. Respiratory syncytial virus was minimally inhibited. However, the activity of aspirin against rhinoviruses was more pronounced. Aspirin demonstrated antiviral activity against all human rhinoviruses (HRV), but the effect on members of the "major group" viruses, namely HRV14 and HRV39, was greater than on those of the "minor group," HRV1A and HRV2. CONCLUSIONS: These data demonstrate a specific antiviral activity of aspirin against influenza A virus and HRV. The mode of action against rhinoviruses is still unknown and requires further investigation, as does the possibility of aspirin being effective in vivo to treat the common cold.

In vitro evaluation of the antiviral effects of the homeopathic preparation Gripp-Heel on selected respiratory viruses.

Gripp-Heel is a homeopathic preparation frequently used in the treatment of respiratory viral infections such as various types of influenza and the common cold. The antiviral activity of Gripp-Heel was studied in vitro on human pathogenic enveloped and nonenveloped RNA and DNA viruses. Before the antiviral assays, in vitro cytotoxicity of Gripp-Heel was determined with cells used for the infection experiments (HeLa, HEp-2, MDCK, BGM) as well as with mitogen-stimulated peripheral blood mononuclear leukocytes. A concentration of 0.5 of the commercially available product slightly reduced cell viability and proliferative capacity, and experiments on antiviral activity were determined starting with a dilution of 0.2 of the commercially available product. The antiviral activity was determined against a broad panel of enveloped and nonenveloped DNA and RNA viruses with plaque reduction assay, cytopathogenic assays, virus titrations, analysis of the viral proteins in virus-specific enzyme immunoassays, and haemagglutination tests. Control substances were acyclovir (10 microg/mL), ribavirin (6 microg/mL), and amantadine hydrochloride (5 microg/mL), depending on the virus type. Gripp-Heel demonstrated dose-dependent in vitro activity (significant reductions of infectivity by 20% to 40%) against Human herpesvirus 1, Human adenovirus C serotype 5, Influenza A virus, Human respiratory syncytial virus, Human parainfluenza virus 3, Human rhinovirus B serotype 14, and Human coxsackievirus serotype A9. The mechanisms of this antiviral activity are still unclear, but type I interferon induction might be a possible explanation. Further research on this homeopathic preparation seems warranted.

Antiviral activity of Engystol: an in vitro analysis.

OBJECTIVES: To study the effects of the homeopathic preparation Engystol (Biologische Heilmittel HEEL GmbH, Baden-Baden, Germany) on a panel [corrected] of human pathogenic viruses in vitro. DESIGN: The effects of Engystol were studied using plaque-reduction assays and virus titration assays, and by quantification of newly synthesized viral proteins in virus-specific enzyme-linked immunoabsorbent assays (ELISAs). SUBJECTS: The DNA viruses Adeno 5 and herpes simplex type 1 (HSV-1), the RNA virus respiratory syncytial virus (RSV), and human rhinovirus (HRV). RESULTS: A 73% reduction of Adeno 5 specific proteins and an 80% reduction in HSV-1 specific proteins were observed in ELISAs of virus-infected cells treated with Engystol after infection. The effects appeared to be dose-dependent. With these viruses, similar results were observed in titration assays of viral offspring from cells treated with Engystol. Pretreatment of adenovirus with Engystol did not inhibit the infectivity of the virus suspension and no Engystol-induced stimulation of interferon-alpha could be observed. Plaque-reduction assays with the RNA viruses, RSV and HRV, showed reductions in infectivity by 37% (RSV) and 20% (HRV), respectively. CONCLUSIONS: The results indicate antiviral activity of Engystol independent of the activation of the cellular interferon system.