Application of Fluorescence in Situ Hybridization in Detection
of Brucella and Mycobacterium bovis
Compared with traditional methods of pathogen isolation and identification,fluorescence in situ hybridization(FISH)technology could be used to rapidly identify pathogenic bacteria due to its obvious advantages. However,there has been no any formal FISH technology for two kinds of major zoonoses(animal brucellosis and bovine tuberculosis)in China. In order to develop the FISH technology for rapidly diagnosing the two diseases,the probes of Brucella(Bru-996)and Mycobacterium tuberculosis(MTB770)were used to determine the optimal detection procedure by optimizing the temperature and time of hybridization,dealing with samples and optimizing other important conditions. Then the specificity and sensitivity of the two probes were evaluated based on strains with known background and clinical samples. The results showed that Brucella could be detected within 4 hours after reaction conditions were optimized. The hybridizations between Bru-996 probe and Brucella strains were positive,and that between Bru-996 probe and Mycobacterium bovis,Mycobacterium avium and Escherichia coli were all negative;and Brucella was successfully detected from five tissue materials with known background. It would take 6 to 8 hours when Mycobacterium bovis was detected,and samples must be treated with Xylene and Lysozyme prior to hybridization. Mycobacterium bovis could be identified and detected from bovine pulmonary nodules by MTB770 probe. In view of the advantages of FISH technology of rapidity and convenience,and the high specificity of Bru-996 and MTB770 probes in detection of Brucella and Mycobacterium bovis,it was believed that the developed FISH technology could replace relevant traditional methods and be used to diagnose animal brucellosis and bovine tuberculosis in laboratories.