CHI3L1 and asthma: Elevated levels of human chitinases (e.g., AMCase) and chitinase-like proteins (e.g., YKL-40) were found in sera and lung tissues of patients suffering from asthma [40,41,42] and it is tempting to speculate that human chitinase-like proteins as well as chitinase-like allergens may have chemotactic activity and perhaps recruit eosinophils and T cells to sites of inflammation [43].