A C6-hemisuccinate derivative of morphine was prepared and conjugated to bovine serum albumin and ovalbumin. High titer antibody producing spleen cells were removed and fused with myeloma cells of SP2/0 origin. Using a conventional immunization protocol generated twenty-six stable murine monoclonal antibodies (MAbs) producing cell lines to morphine. The donor mouse produced antiserum with a high titer of 1/640,000. Twelve MAbs were selected for further characterization since they showed high sensitivities (53 pg/well to inhibit 50% of the tracer) in improved group-selective immunoassay (IGSI). The assay, which maintains high sensitivity, high precision, and a wide range of optical density (OD) values, was developed using the conjugate M-6-S-OVA to screen and characterize the anti-morphine MAbs. After four successive limiting dilutions, antibodies produced by 12 clones had high affinities ranging from 10(9) to 10(10) M(-1). These clones were found to be of Ig(G) class and IgM class with kappa and lambda light chain. Subclass determination showed that the clones produced IgG1, IgG2a, IgG3, and IgM types of antibody. One clone (2F8B11F2A12) was used to establish the calibration curve with a sensitivity of 400 pg/mL covering up to 25.6 ng/mL in urine.

ABSTRACT. Protocadherins constitute a large family belonging to the cadherin superfamily; they function in various tissues of a wide variety of multicellular organisms. However, their functions and expression modes are still unknown in many of these species and tissues. We developed a fast and low-cost method to produce polyclonal antibody against chicken protocadherin 1 (Pcdh1) that could be used in assays for immunological assessment of protein expression levels of chicken Pcdh1. Primers were designed with DNAStar, using the nuclear sequence of pcdh1 as a template; the pcdh101 fragment was amplified, identified by sequencing and cloned into expression vectors pGEX-2TK and pET-32a, separately, resulting in 2 recombinant plasmids, pGEX-2TK-pcdh101 and pET32a-pcdh101. These were confirmed by double-enzyme digestion and sequencing. The recombinant expression vectors were transformed and expressed in Escherichia coli BL21. The recombinant oligopeptides glutathione-S-transferase (GST)-Pcdh101 and (His) 6 -Pcdh101 fused with the carrier protein GST and (His) 6 separately, and were purified. Rats were immunized by injecting the emulsified GST-Pcdh101 antigen subcutaneously into their hind footpads, followed by a booster injection after 2 weeks. One week after the booster, the sera were collected and examined for antibody titer by indirect ELISA. The optimal dilution of this antiserum was 1:300. The specificity of the antiserum was confirmed by Western blotting. This antiserum had good specificity and could be used to detect chicken Pcdh1 in Western blot analysis. This method allows production of specific rat polyclonal antisera for Western blots in less than 1 month at a relatively low cost.