CILP2 and osteoarthritis: For example, it has been shown in animal studies that CILP-1 and CILP-2 display different expression patterns in cartilage during osteoarthritis, with CILP-1 being upregulated and CILP-2 downregulated [6], while proteomic analysis of cartilage samples taken from patients with osteoarthritis has shown increased levels of CILP-2 [9].