Kallestad Diagnostics

Kallestad Diagnostics was a prominent medical diagnostics company founded in 1967 and headquartered in Chaska, Minnesota, with significant operations in Austin, Texas. The company established itself as a global leader in the development of immunofluorescence (IFA) and enzyme immunoassay (EIA) technologies, providing critical tools for the diagnosis of autoimmune diseases, infectious diseases, and allergies. In 1988, Kallestad was acquired by Sanofi and integrated into Sanofi Diagnostics Pasteur, where it contributed to the development of the Access Immunoassay System, a platform later sold to Beckman Coulter. In 1999, Bio-Rad Laboratories acquired Sanofi's diagnostics division for $210 million, incorporating Kallestad's extensive product lines into its portfolio. Today, the Kallestad brand remains a recognized name under Bio-Rad, particularly for its industry-standard HEp-2 slides used in antinuclear antibody (ANA) screening.