Abstract
The development of Mumps fluorescent and neutralizing antibody in saliva and its relationship to virus excretion were studied in the case of natural infection. The antibody produced in serum was also measured in comparison with that in saliva.
1) In most cases, IgA antibody began to be detected in saliva on the 4th day after the onset of disease and reached a titer of 1:8 or below, as measured by the indirect immunofluorescentt echnique. LgM antibody also appeared almost at the same time to reach a titer of 1:4 or below, but its persistence was shorter than that of IgA antibody. IgG antibody was detected from several cases, but titer was 1:2 or below and showed a tendency to disappear gradually.
2) Mumps virus was isolated from saliva until the 5th day after the onset of disease. In many cases the development of antibody coincided with the end of virus excretion.
3) Serum IgG antibody reached a titer of 1:128 or 1:512 in 4 cases. In these cases, however, no IgG antibody was detected in saliva. IgM antibody reached a titer of 1:16 or 1:32 in serum and titers of 1:2 and 1:4 in saliva in 2 cases. IgA antibody reached a titer of 1:8 or 1:16 in serum and a titer of 1:2 or 1:8 in saliva in all these cases.
4) Specific antibody was detected in parotid fluid which had been collected directly from Stensen's duct.
Because of the presence of antibody activity mainly in IgA, the coincidence of its development with the end of virus excretion, an very great difference in antibody response between saliva and serum, and the presence of antibody in protid fluid, the specific antibody was supposed to be produced in salivary glands by virus proliferation.
It was presumed that the antibody response of salivary glands might have an important role in the inhibition of growth of mumps virus and its excretion into saliva.
