Vaccination with Detoxified Leukocidin AB Reduces Bacterial Load in a Staphylococcus aureus Minipig Deep Surgical Wound Infection Model

Vaccines against Staphylococcus aureus have eluded researchers for >3 decades while the burden of staphylococcal diseases has increased. Early vaccine attempts mainly used rodents to characterize preclinical efficacy, and all subsequently failed in human clinical efficacy trials. More recently, leukocidin AB (LukAB) has gained interest as a vaccine antigen. We developed a minipig deep surgical wound infection model offering 3 independent efficacy readouts: bacterial load at the superficial and at the deep-seated surgical site, and dissemination of bacteria. Due to similarities with humans, minipigs are an attractive option to study novel vaccine candidates. With this model, we characterized the efficacy of a LukAB toxoid as vaccine candidate. Compared to control animals, a 3-log reduction of bacteria at the deep-seated surgical site was observed in LukAB-treated minipigs and dissemination of bacteria was dramatically reduced. Therefore, LukAB toxoids may be a useful addition to S. aureus vaccines and warrant further study.

A prospective study of 18 patients with cholestasis of pregnancy

In this prospective study we evaluate the role of serum bile acids in the investigation and management of cholestasis of pregnancy in a detailed study of 18 patients. Bile acids were the most sensitive diagnostic test. The increased incidence of fetal distress (33.3% in this series) and meconium-stained fluid (58.3%) did not correlate with very high values of bile acids in maternal serum, umbilical cord serum, or amniotic fluid. Treatment of pruritus with cholestyramine and/or phenobarbital is ineffective in this condition, induction of labor is suggested once fetal lung maturity is established.

Triiodothyronine binding affinity for thyroxine-binding globulin in serum from normal subjects and from hyperthyroid, hypothyroid and pregnant patients

The binding of 3,5,3'-triiodothyronine (T3) to thyroxine-binding globulin (TBG) was quantitated in pooled serum from normal, hyperthyroid, hypothyroid and pregnant subjects. To aliquots of each pool was added a small quantity of 131I-T3 and varying concentrations of unlabelled T3 or thyroxine (T4). Following countercurrent electrophoresis in both barbital and trismaleate buffers at pH 8.6, the concentration of 131I-T3 bound to TBG was calculated and the displacing effect of unlabelled T3 and T4 compared. The displacement of 131I-T3 from TBG was greater with T4 than with T3 when normal, hypothyroid and pregnancy sera were electrophoresed in barbital buffer (which inhibits thyroid-binding prealbumin (TBPA) binding of T4). The same findings are seen when hyperthyroid serum which is deficient in TBPA is electrophoresed in trismaleate buffer (which does not inhibit TBPA binding of T4). The observed data indicate that T4 has a greater binding affinity for TBG than has T3 but only displaces T3 to significant degree when TBG is saturated and when TBPA binding of T4 is reduced or inhibited. TBG binding capacities for T3 have been derived for each of the 4 clinical groups and appear to be less than corresponding binding capacities for T4.