Storage stability of different antibody species against arbovirus and rickettsial antigens in blood dried on filter paper discs.

Abstract

Citrated human bloods containing yellow fever virus hemagglutination-inhi biting (HI) antibodies predominantly in the IgA, IgM or IgG immunoglobulin classes, epidemic typhus agglutinating (MA) antibodies distributed between IgG and either IgA or IgM immunoglobulins and typhus complement fixing (CF) antibodies in the IgG immunoglobulin class were dried on filter paper discs. After sealing in moisture-proof bags, groups of discs were stored at –20, +4, +26 and +37 C. EJuates prepared from the discs at intervals after drying were tested for the recovery of specific antibody activity. Antibody activity attributable to IgM immunoglobulin declined rapidly upon storage, regardless of temperature. Thus, yellow fever HI antibodies belonging to the IgM immunoglobulin class were not detectable in eluates which had been stored for 1 month, even at —20 C. In contrast, antibody activity residing in the IgG immunoglobulin class appeared to be relatively stable on filter paper discs over a 4 month period, especially when stored at lower temperatures. Stability of IgA antibodies requires further study. Interpretation of serologic data obtained from studies employing the filter paper disc technique must take into account differences in storage stability of the various classes of immunogbbulins.