Lynn Wang

Stereospecific antibodies to propranolol

The β‐adrenergic antagonist propranolol was activated through its side chain, coupled to bovine serum albumin, and injected into BALB/c mice. After fusion of the splenocytes from these immunized mice with the NS‐1 myeloma cell line, two hybridomas, producing monoclonal anti‐propranolol antibodies, were isolated. Clone P‐49 was monospecific for propranolol, with a significant preference for the 1‐stereoisomer, as compared to the d form. On the other hand, clone P‐28 cross‐reacted with alprenolol as well as some other β‐antagonists. Both classes of antibodies competed with A431 epidermoid carcinoma β2‐adrenoceptors for the binding of [3H]propranolol. When ascites cells from clone P‐28 were fixed with glutaraldehyde, the anti‐propranolol monoclonal antibody became cell bound. These cell‐bound P‐28 antibodies bind propranolol and other β‐adrenergic ligands with a similar ranking order to the soluble monoclonal antibody. The cell‐bound antibody displayed a 5‐fold higher affinity towards 1‐propranolol than the soluble monoclonal antibody. The practical implications of these findings are discussed.

Distribution of surface anionic sites on mouse hybrid myelomas.

The surface anionic site distribution on membranes of a monoclonal antibody-producing hybridoma cell line, and its two parental cells: normal spleen cells of immunized BALB/c mice and cells from a mouse myeloma line (NS-1), were investigated with the aid of the cationized ferritin (CF) labelling method, following glutaraldehyde/formaldehyde fixation of cells. The patch-like CF distribution on the hybridoma cells is similar to that of the NS-1 myeloma cells, but distinct from the even and continuous CF distribution of the immunized and nonimmunized normal spleen lymphocytes. The similarity in the formation of patch-like CF heaps, both on myeloma and hybrid cells is discussed in respect to the surface charge characteristic determined by cell fusion.