== Antibody titers of FBZ-treated mice Mice were treated continuously for 35 d and by an onoff protocol for 63 d. many standard broad steps of immune function. Abbreviation:Con A, concanavalin A; FBZ, fenbendazole; LPS, lipopolysaccharide Fenbendazole (FBZ) is usually a broad-spectrum benzimidazole anthelmintic drug that has gained widespread use for the treatment and prophylaxis of pinworm contamination.12,20,25FBZ typically is administered through the use of medicated feed and is often used instead of ivermectin, which can have toxic effects in young animals.24Although no toxic effects have been reported from the use of FBZ at therapeutic levels, the physiologic or biologic actions of the drug potentially might alter or interfere with ongoing research experiments.22,25To this point, treatment with FBZ apparently decreases fecundity but not reproduction in rats.14,27Furthermore, FBZ had no effect in rat behavioral studies.3,15Recently, FBZ reportedly enhanced lipopolysacchide-induced inflammation in rats.13 FBZ treatment alters numerous immune parameters in nonrodent species including inducing myelosuppression and altering T and B cell responses.5,10,11,19,23,26In contrast, FBZ treatment (150 ppm) for 23 wk did not alter the onset or incidence of diabetes in NOD mice.9Furthermore, assays of T helper function and cytotoxicity remained unaffected in BALB/c mice treated for 2 wk with 100 ppm FBZ.21In contrast, FBZ at 10mg/kg for 5 d in C57BL/6 mice resulted in increased spleen cell proliferation to mitogens.8The goal of the current study was to examine BALB/c mice for changes in routine parameters and assessors of immune function during and after treatment with a commercially available FBZ-medicated (150 ppm) diet. Many treatment protocols using FBZ-medicated diet have been proposed.12,20This study was conducted by using both a 9-wk onoff schedule as well as 5-wk continuous application. == Materials and Methods == == Animals and housing. == All animals ITIC were maintained in accordance with the heat and humidity recommendations of theGuide for the Care and Use of Laboratory Animals18at the AAALAC-accredited facilities of the University of Miami. All experimental procedures were approved by the university’s ITIC Animal Care and Use Committee. Sentinel mice maintained on dirty bedding were screened quarterly for: mouse hepatitis computer virus, Sendai computer virus,Mycoplasma pulmonis, pneumonia computer virus of mice, minute computer virus of mice, Thieler murine encephalomyelitis computer virus, mouse parvovirus, mouse rotavirus, lymphocytic Mouse monoclonal to COX4I1 choriomeningitis computer virus, and parasitic infections. Once a year, the panel was extended to include mouse norovirus,Ectromeliavirus, K computer virus,Encephalitozoon cuniculi, polyoma computer virus, mouse adenovirus, reovirus, murine cytomegalovirus, hantavirus, mouse thymic computer virus,Clostridium piliforme, and cilia-associated respiratory bacillus.Helicobactertesting by PCR was conducted also. All results were unfavorable during the course of this study. BALB/c female mice purchased from Charles River Laboratories (Wilmington, ITIC MA) were used throughout the studies and were 8 wk of age on arrival. C57BL/6 mice used as skin-graft donors were obtained from an inhouse breeding colony. Mice were conventionally housed in groups of 5 animals per cage by using nonautoclaved shredded aspen bedding (Harlan Teklad, Madison, WI) and microisolation filter tops. They were given ad libitum access to rodent chow and municipal water by bottle. Regular chow was purchased from PMI International (Lab Diet 5001; Richmond, IN). Fenbendazole medicated diet was purchased from Harlan Teklad (Irradiated Global Diet 2018 with 150 ppm FBZ). The concentration of FBZ ITIC was verified through analytical testing at a reference laboratory. Animals were bled by using the submandibular method, and blood was placed in a lithium-heparinized tube (Capijet, VWR, West Chester, PA) for complete blood count and chemistry analyses. Blood was placed in an anticoagulant-free tube (Capijet, VWR) for the antibody studies. Animals used for the in vitro assays were euthanized by cervical dislocation to minimize cellular changes in the lymphoid tissues. All other animals were euthanized by CO2inhalation. For the 9-wk onoff treatment schedule, time points of days 21, 35, and.