Isolation of mammalian type C RNA virus cross-reactive antigen and antibody by immuno-affinity chromatography

Sperm isolation and biochemical analysis of the major sperm protein from Caenorhabditis elegans

In order to facilitate the biochemical analysis of spermatogenesis in the nematode Caenorhabditis elegans methods have been developed for obtaining large quantities of males and for the isolation of sperm. Males are isolated by a passive filtration method from strains producing high proportions of males and sperm are isolated by physical pressure followed by filtration and differential centrifugation. Biochemical analyses show that sperm contain a major protein component that represents 17% of the total sperm protein. This protein has a molecular weight of 15,600, an isoelectric pH of 8.6, and exists as a dimer. It is shown by immunocytochemical techniques to be a specific product of spermatogenesis. It is localized in the proximal arm of the male gonad and in the sperm of both the male and hermaphrodite but it is not detected in other tissues of the nematode. It is not a nuclear binding protein. Pulse-labeling studies show that this major sperm protein is first synthesized in the proximal arm of the male gonad beginning at 39-42 hr after hatching at 20 degrees C. Poly(A) mRNA coding for this protein is first detected in a translatable form just before synthesis of this sperm protein suggesting transcriptional control.

Isolation of anti-haemagglutinin antibodies with an influenza A virus immunoadsorbent

The X-31 strain of influenza A (H3N2) virus has been covalently bound to CNBr activated agarose for the separation of anti-haemagglutinin antibodies. The virus immunoadsorbent was used repeatedly under high ionic strength alkali buffer and acid conditions without altering appreciably its antibody binding capacity. Sequential elution of bound anti-haemagglutinin antibodies with increasing concentrations of sodium iodide has enabled the physical separation of antibody populations with low and high avidity for the virus immunoadsorbent. In haemagglutination inhibition (h1) assays, the less avid population reacted only with the homologous X-31 virus, wheras the more avid antibody population reacted both with the homologous and the related cross-reactive A/England/42/72 (H3N2) strains. Sequential elution under acid conditions did not completely remove the bound anti-haemagglutinin antibodies and those eluted retained little of their anti-haemagglutinin activity. From a practical point of view, given a specific antiserum, it is feasible to use whole virus as an immunoadsorbent for the purpose of isolating populations of antibodies of different avidities and cross-reactivities. Furthermore, sodium iodide as an eluting agent has proved most effective in recovery of active and stable antibodies from the agarosebound virus.