Th 5 thermalert clinical monitoring thermometer

Wild-type C57BL/6J mice (The Jackson Laboratory) and whole-body Gpd2−/− mice were maintained under specific pathogen-free conditions at the Harvard T.H. Chan School of Public Health in accordance with Institutional Animal Care and Use Committee (IACUC) guidelines. Male and female mice were used for in vivo LPS tolerance experiments and as a source of bone marrow for BMDM culture between 6 and 12 weeks of age. All protocols were approved by the IACUC of Harvard Medical School. In the in vivo LPS tolerance experiments, wild-type and Gpd2^−/− mice were injected with vehicle (saline) or 3 mg/kg LPS via intraperitoneal injection (IP) followed by 30 mg/kg LPS IP 24h later. Serum IL-6 and internal body temperature (TH-5 Thermalert Clinical Monitoring Thermometer, Physitemp) were measured for 6 h after lethal LPS challenge. Survival of wild-type and Gpd2^−/− mice that received both challenges was recorded as an indication of differential endotoxin tolerance in vivo.

A FLIR E6 infrared thermal camera (FLIR Systems, Wilsonville, OR) was used to measure surface body temperature (14 (link)). After mice were removed from nests, the surface temperature was immediately obtained using a double-blind protocol. During capture of thermal images, animal behavior and scanning distance were controlled to avoid artificial effects. For reduction of variances, rectal body temperature was also measured using a highly precise electronic thermometer (TH-5 Thermalert Clinical Monitoring Thermometer; Physitemp Instruments).