Antiviral composition and method of use

#The present invention is in the field of immunology and antiviral agents and relates to a pharmaceutical composition comprising carrageenan as an active antiviral ingredient and to applications thereof in the prevention or therapeutic treatment of rhinovirus infections.

#Picornaviruses represent a very large virus family of small ribonucleic acid-containing viruses responsible for many serious human and animal diseases. Picornaviruses include four major groups: enteroviruses, rhinoviruses, cardioviruses and apthoviruses.

#The human rhinoviruses consist of at least 100 serotypes and are the primary causative agents of the common cold. Because of the large number of serotypes, development of a vaccine is problematic; antiviral agents may therefore be the best approach to treatment. Rhinoviruses are composed of a surrounding capsid, which contains four viral proteins VP1, VP2, VP3 and VP4. Proteins VP1, VP2 and VP3 are organized into 60 repeating protameric icosahedral units. These are thought to be the cause of antigen diversity associated with these viruses.

#FIG. 1 shows the results of a HRV induced cell death inhibition assay (XTT-assay). Ordinate=OD measured at 492 nm; abscissa=different test samples; 1=uninfected cells; 2=untreated, infected cells; 3=infected cells treated with iota-carrageenan; 4=infected cells treated with kappa-carrageenan; 5=infected cells treated with lambda-carrageenan; FIG. 1A=cells infected with HRV-2; FIG. 1B=cells infected with HRV-14.

#FIG. 2 shows the determination of peak titers of supernatants from infected Hela cells by TCID50 assays. Ordinate=TCID50 titer; abscissa=concentration of iota-carrageenan in μg/ml; U=untreated cells; T (treatment)=cells were infected for one hour and the indicated concentration of iota-carrageenan was added one hour after treatment; P (prophylaxis)=the virus suspension was preincubated with the indicated concentration of iota-carrageenan for on hour before infection. Further processing was identical to T: cells were infected at a multiplicity of infection of 0.01. The peak titers were observed at day 3 for HRV-2 (FIG. 2A) and at day 4 for HRV-14 (FIG. 2B).

#FIG. 3 shows the efficacy of iota-carrageenan on inhibition of rhinovirus replication on infected human nasal epithelial cells determined by TCID50 assays. Ordinate=TCID50 titer in logs; abscissa=concentration of iota-carrageenan in μg/ml; MOCK=untreated control cells; FIG. 3A=cells infected with HRV-1A; FIG. 3B=cells infected with HRV-2; FIG. 3C=cells infected with HRV-8; FIG. 3D=cells infected with HRV-16; FIG. 3E=cells infected with HRV-39; FIG. 3F=cells infected with HRV-83.

#In order that the invention described herein may be more fully understood, the following examples are set forth. The examples are for illustrative purposes only and are not to be construed as limiting this invention in any respect. It is further understood that the present invention shall also comprise variations of the expressly disclosed embodiments to an extent as would be contemplated by a person of ordinary skill in the art.

#Subconfluent HeLa cells were incubated with a virus suspension that was preincubated for 5 min with 125 μg/ml of the polymers as indicated in FIG. 1. 48 hours later the viability of the cells was determined with TOX2 XTT assay (Sigma).

#As shown in FIG. 1, it was found that the most effective polymer was iota-carrageenan (column 3) which was effective against both types of rhinovirus while, lambda-carrageenan (column 5) and kappa-carrageenan (column 4) showed efficacy against HRV-2 but not against HRV-14. Error bars indicate the standard deviation between six independent wells.