The expectation was that the bacteria that cause PID were multiple genetically diverse opportunist pathogens of the endometrium. However in the present study, selleck chemical Veliparib clonal groups of E. coli identified by Triplex PCR, RAPD and MLST were isolated from the endometrium of postpartum animals. The E. coli isolated from the uterus lacked many common virulence genes associated with DEC or ExPEC bacteria. The clonal E. coli associated with PID were more adherent and invasive for endometrial epithelial and stromal cells than clonal bacteria isolated from clinically unaffected animals. The bacteria or the LPS caused PID or endometritis in mice when infused into the uterus in vivo. Furthermore, LPS purified from the E. coli associated with PID provoked inflammatory responses by bovine endometrial cells in vitro.

Murine endometrial cells also responded to LPS via a TLR4 dependent pathway. Taken together, the data provide evidence for specific strains of endometrial pathogenic E. coli that cause PID, which were designated as EnPEC. The implications of the findings are that development of vaccines or biological therapeutics for PID should specifically target EnPEC rather than other E. coli strains. The E. coli isolated from the uterus of postpartum animals were mainly from Triplex-PCR groups A, B1 and D, with only 3 isolates from the B2 category. Group A and B1 E. coli are usually considered commensal in the intestine and are commonly shed into the feces of healthy animals [11], [12], [28]. On the other hand, ExPEC preferentially belong to group B2 and D [28] and E.

coli that cause mastitis strains are usually group A or D [23]. Although the distribution of phylogroups in the present study was similar to that for E. coli isolated from feces, fecal E. coli have a wide genetic diversity between animals and over time [29]. Indeed, the isolates from animals with PID were predominantly in the B1 and A groups and more likely to be collected during the first two weeks post partum, whereas E. coli from the uterus of unaffected animals were distributed more equally between the A, B1 and D groups, and throughout the first four weeks after parturition. The RAPD analysis revealed that multiple isolates within a phylogroup were similar in overall genotype, and this refined subgroup of E.coli strains was further characterized by MLST and serotyping. A cluster of E.

coli was identified by MLST that was only isolated from unaffected Carfilzomib animals (cluster 1) and three clusters of bacteria were associated with PID (clusters 2 to 4). In addition, the uterine derived bacteria clustered apart from 11 reference strains of E. coli evaluated in the MLST dendrogram, including DEC, ExPEC and a bovine mastitis strain. Strains from PID and unaffected animals had diverse serogroups. However, when analyzed in concert with MLST it was apparent that all of the E.