Functional differences of dyes in inducing respiratory immunogenicity by azo-, thiazole-, quinoline-, reactive-, and naphthol-dye-inactivated Sendai viruses.

The prophylactic effects by mouse nasal inoculation of 31 kinds of organic dye-inactivated Sendai viruses were investigated by contact exposure experiment that used mouse nasally infected with 10(5.8) EID50, immunofluorescent examination of the entire respiratory tract, and check of rise of serum HI titer postexposure. The relative merits of the dye-structures for inciting nasal immunogenicity were determined. Of 14 azo-dye-inactivated vaccines, only azo blue- and amido black 10B treated ones brought about nearly complete protection, while the other 5 dye-groups provided partial protection and the remaining 7 dye-groups the least protection. Of 6 thiazole dye-vaccines, primuline-, thioflavine S-, and thioflavine T-vaccines induced complete or almost complete protection, and the others moderate or the least protection. With 3 quinoline-vaccines, both pinacyanol- and quinaldine red-inactivated ones provided complete protection, but not with quinoline blue-vaccine. Of 4 reactive dye-vaccines, both cibacron brilliant yellow 3G-P- and reactive blue 4-treated ones brought about nearly complete protection, but the remaining 2 vaccines induced regional infection. Nevertheless, all 4 naphthol group (AS, AS-BS, AS-BI, and AS-MX)-treated vaccines yielded complete or almost complete protection. The thirteen most effective vaccine groups suppressed marked rise of high or low serum HI titers developed through nasal vaccination postexposure. In short, specified dyestuffs having a great affinity for cellulosic fibers, evidently incited mucosal immunogenicity, probably by major union of the dyes to viral core ribose.