Lactobacillus casei BL23 modulates the innate immune response in Staphylococcus aureus-stimulated bovine mammary epithelial cells.

Probiotics have been adopted to treat and prevent various diseases in humans and animals. They were notably shown to be a promising alternative to prevent mastitis in dairy cattle. This inflammation of the mammary gland is generally of infectious origin and generates extensive economic losses worldwide. In a previous study, we found that Lactobacillus casei BL23 was able to inhibit the internalisation of Staphylococcus aureus, one of the major pathogens involved in mastitis, into bovine mammary epithelial cells (bMEC). In this study, we further explored the capacity of this strain to modulate the innate immune response of bovine mammary epithelial cells during S. aureus infection. L. casei BL23 was able to decrease the expression of several pro-inflammatory cytokines, including interleukins 6, 8, 1α and 1ß and tumour necrosis factor alpha, in S. aureus-stimulated bMEC, 8 h post-infection. On the other hand, L. casei did not impair the induction of defensins, such as lingual antimicrobial peptide and defensin ß1 in the presence of S. aureus, and even slightly increased the induction of tracheal antimicrobial peptide during S. aureus infection. Finally, this strain did not alter the expression of the pattern recognition receptor nucleotide-binding oligomerisation domain proteins (NOD2). This study demonstrates that L. casei BL23 displayed anti-inflammatory properties on S. aureus-stimulated bMEC. These results open the way to further characterisation of the BL23 probiotic potential in a bovine mammary gland context and to a better understanding of how all these beneficial properties combine in vivo to combat mastitis pathogens.

CHRM3 rs2165870 polymorphism is independently associated with postoperative nausea and vomiting, but combined prophylaxis is effective.

BACKGROUND: Clinical risk factors for postoperative nausea and vomiting (PONV) are evaluated with the Apfel score, however patients with low Apfel scores still experience PONV suggesting a genetic predisposition. PONV risk associates with specific M3 muscarinic acetylcholine receptor (CHRM3) rs 2165870 polymorphism. We investigated whether the Apfel score and this genetic variation independently contribute to PONV risk and whether prophylaxis reduces PONV in patients with low Apfel score but at high genetic risk. METHODS: In a prospective, controlled study, 454 subjects undergoing elective surgery were genotyped for rs2165870 and its association with PONV was investigated with log-binomial regression analysis. Subjects were randomised to receive acustimulation/dexamethasone, acustimulation/vehicle, sham acustimulation/dexamethasone, or sham acustimulation/vehicle to investigate their effects on PONV risk. RESULTS: Early PONV occurred in 37% of subjects. The rs2165870 genotype distribution was GG in 191, GA in 207, and AA in 56 subjects. The CHRM3 polymorphism was associated with a relative risk (RR) of 1.5 for GA vs GG [95% confidence interval (CI): 1.1-1.9; P=0.003] and 1.6 for AA vs GG (95% CI: 1.1-2.2; P=0.009) genotypes to develop PONV, and this was independent from the Apfel score (RR per Apfel point: 1.3, 95% CI: 1.2-1.5; P<0.0001). While dexamethasone and acustimulation each reduced the PONV risk by 30% in AA genotype carriers with low Apfel score, combined therapy reduced the risk by 86% (P=0.015). CONCLUSIONS: The CHRM3 polymorphism and the Apfel score independently predict PONV susceptibility. Dexamethasone/acustimulation should be considered in patients with low Apfel score but at high genetic risk. CLINICAL TRIAL REGISTRATION: DRKS00005664.

High seroprevalence of caseous lymphadenitis in Brazilian goat herds revealed by Corynebacterium pseudotuberculosis secreted proteins-based ELISA.

We conducted a seroepidemiological survey to determine the prevalence of caseous lymphadenitis (CLA) in goat herds in Minas Gerais state, Brazil. Serum samples were collected from goats (n=676) from 108 rural properties in 2001, covering most of the sub-regions of this ca. 586,500 square kilometer state. Antibodies against Corynebacterium pseudotuberculosis secreted proteins were detected by an indirect enzyme-linked immunosorbent assay (ELISA). Most of the animals (78.9%) tested positive for CLA; 98% of flocks presented at least one seropositive animal. Goats managed under an extensive production system had a significantly higher seroprevalence of CLA than those in intensive and semi-intensive operations. The age distribution of the animals in the flocks affected the prevalence of this disease; however, goat breed did not. We found seropositivity against C. pseudotuberculosis to be highly prevalent in these Brazilian goat herds; consequently, appropriate management practices for the control of CLA should be implemented.

Evaluation of the anti-LipL32 monoclonal antibodies potential for use in leptospirosis immunodiagnostic tests.

LipL32 is the major lipoprotein in the membrane of pathogenic leptospira. In this work, we report on the production of monoclonal antibodies (MAbs) against recombinant LipL32 (rLipL32) and on the evaluation of their potential for use as reagents in diagnostic tests for leptospirosis. The MAbs were all of the IgG(2b) isotype and reacted specifically with native LipL32 in pathogenic serovars only. MAbs reacted in the same region of the rLipL32 molecule and their affinity constant was between 5x10(7) M(-1) and 6x10(6) M(-1). These results suggest that although the MAbs cannot be used together, they are well suited for diagnostic tests of leptospirosis based on LipL32 detection.