RESUMO
The rapid detection of food-borne bacterial pathogens as part of a quality control program is necessary for the maintenance of a safe food supply. In this report, we present our findings for an immunocapture PCR method for the detection of Campylobacter jejuni in foods. The method permits direct detection of the pathogen without an enrichment step and can be performed in approximately 8 h. Assay results are quantitative, and one cell in a milliliter sample can be detected. Application of the method to spiked milk samples and chicken skin washes did not affect the sensitivity of the assay.
Assuntos
Campylobacter jejuni/isolamento & purificação , Galinhas/microbiologia , Microbiologia de Alimentos , Separação Imunomagnética/métodos , Leite/microbiologia , Reação em Cadeia da Polimerase/métodos , Animais , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Criança , DNA Bacteriano/análise , DNA Ribossômico/análise , Feminino , Humanos , RNA Ribossômico/genética , Sensibilidade e EspecificidadeRESUMO
Maitotoxin is a water-soluble polyether toxin produced by the benthic dinoflagellate, Gambierdiscus toxicus. Toxin fragments generated by periodate oxidation were conjugated to keyhole limpet hemocyanin, and the resulting immunogens were used to elicit maitotoxin-specific antibodies in mice. A competitive immunoassay developed with polyclonal IgG antibodies detected approximately 3 nM purified maitotoxin standard (IC50 approximately 13 nM; 45 ng/ml) but did not detect other polyether marine toxins. These are the first reported maitotoxin-specific antibodies.
Assuntos
Antitoxinas/biossíntese , Imunização/métodos , Imunotoxinas/imunologia , Toxinas Marinhas/imunologia , Oxocinas , Animais , Ligação Competitiva , Proteínas de Transporte/imunologia , Hemocianinas/imunologia , Imunoglobulina G/biossíntese , Camundongos , Fragmentos de Peptídeos/imunologia , Soroalbumina Bovina/imunologiaRESUMO
Three monoclonal antibodies with either specificity to taxol or baccatin III, or cross-reactivity with several common taxanes have been prepared and used to develop sensitive competitive-inhibition enzyme immunoassays. The hybridomas producing these monoclonal antibodies were obtained by fusing P3X63Ag8.653 plasmacytoma cells and splenocytes from mice hyperimmunized with keyhole limpet hemocyanin-7-succinyltaxol or -7-succinylbaccatin III conjugates. Direct and indirect competitive inhibition enzyme immunoassays were developed with these monoclonal antibodies and microtiter plates coated with bovine serum albumin conjugates of the complementary hapten. Detection limits for the direct competitive inhibition enzyme immunoassays, conducted in buffer containing 10% MeOH, were 0.6 nM taxol for 3C6 (anti-taxol); 1.1 nM baccatin III for 3H5 (anti-baccatin III); and 0.6 nM taxol or baccatin III for 8A10 (anti-taxane). The immunoassays accurately detected taxol, baccatin III, and "total taxanes" in crude MeOH extracts of Taxus brevifolia bark and in hplc fractions of these extracts.
