To explore whether or not Ca2+-signalling components are associated with another type of serpinopathy; AAT deficiency, we measured basal free calcium, responses to TG, and store-operated Ca2+-entry (SOCE) in CHO K1 cell lines stably expressing the wild type human AAT (MAAT) and the disease-causing variants (ZAAT and NHK AAT). This evidence concerns the gene SERPINA1 and alpha 1-antitrypsin deficiency.