Thioglycollate Use in Rodents (IACUC)

Policy

Adherence to this policy is mandatory unless a specific exception has been approved by the IACUC.

The use of thioglycollate must be described in the IACUC protocol. Treated mice must be monitored daily for abnormal clinical signs, to include hunched posture, ruffled fur, lethargy, and decreased BCS. Humane endpoints warranting euthanasia must also be described in the protocol, such as abnormal clinical signs or a BCS of less than 2.

Guidelines

Thioglycollate is used for induction of activated macrophages and granulocytes in mice. This compound can be used as a means to recover activated inflammatory leukocytes from mice or it can be used to compare rates of leukocyte accumulation in different strains of mice.

Recommendations for thioglycollate administration:

1. Intraperitoneal injection of a sterile thioglycollate medium (3% wt/vol of an autoclaved stock prepared from dehydrated thioglycollate medium and sterile saline water) using a 27 Ga needle (or smaller).
2. Dose volume for mice ≥2 months old is 2-3 ml, and 1-1.5 ml for mice that are < 2 months old.

Mice are euthanized for recovery of peritoneal inflammatory cells at various time points following injection. Leukocytes accumulate rapidly in normal mice in response to the injection and large numbers of cells can be recovered after 24-48 hours. Some strains may require up to 4 days to produce adequate numbers of cells. Recommended study length is 1-4 days post-injection, after which animals are euthanized.

References

Schneider, M. (2013). Collecting Resident or Thioglycollate-Elicited Peritoneal Macrophages. In: Allen, I. (eds) Mouse Models of Innate Immunity. Methods in Molecular Biology, vol 1031. Humana Press, Totowa, NJ. https://doi.org/10.1007/978-1-62703-481-4_4

History

Effective Date: 08/02/2022
Next Review Date: 08/01/2025