Bacterial Immunoabsorbent Columns

Diethylaminoethyl-cellulose-bacterial cell immunoadsorbent columns: preparation of serotype-specific globulin and immunofluorescent conjugates for Streptococcus mutans serotypes a and d

Diethylaminoethyl (DEAE)-cellulose was used as a support material for preparing bacterial cell columns. Pretreatment of the bacterial cells with formalin was essential in obtaining satisfactory adherence of the cells to DEAE-cellulose. Cross-reacting antibodies were removed from antibody preparations against strains of Streptococcus mutans serotypes a and d by adsorption on appropriate bacterial cell columns. S. mutans serotype d was further divided into two subtypes on the basis of immunofluorescent staining with conjugates of immunospecifically adsorbed immunoglobulin G. The DEAE-cellulose-bacterial cell columns were regenerated after use by desorbing the cross-reacting antibodies with low-pH buffer and were used repeatedly over and 18-month period with no detectable loss in effectiveness.

Insolubilized Salmonella lipopolysaccharides as efficient immunoadsorbents for the preparation of specific Salmonella antisera

Lipopolysaccharides (LPS) derived from a single Salmonella serotype or a combination of serotypes were submitted to insolubilization by means of glutaraldehyde. Cross-linked LPS proved to be efficient immunoadsorbents. They were employed for the removal of cross-reacting anti-O antibodies from various Salmonella antisera. LPS immunoadsorbents offer a number of advantages over bacterial cells concerning the preparation of specific bacterial antisera: they regain the original antibody binding capacity after tryptic digestion of the anti-LPS antibodies adsorbed and can be repeatedly used (15 times at least), adsorption of the sera is complete within 30 min, and the procedure is simplified. Prolonged storage (over 3 years) has no deleterious effect on the adsorption properties of the immunoadsorbents. Various applications of LPS immunoadsorbents are described.