CD28 and idiopathic pulmonary fibrosis: For example, Herazo-Maya et al. (2013) performed a microarray expression profile analysis of RNAs expressed in PBMCs obtained from healthy individuals and patients with IPF, and identified some of the differentially expressed mRNAs that included a series of aging-related mRNAs, such as CD28, ICOS, LCK, and ITK. Moreover, Huang et al. (2014) revealed that the expression level of LYCAT was greatly reduced in the PBMCs and lung tissues of patients with IPF, as well as in a mouse model of bleomycin- and radiation-induced IPF.