CXCL10 and asthma: Meta-analysis shows that serum vitamin D levels are positively correlated with improvements in lung function in patients with asthma, which is explained by the anti-inflammatory properties of vitamin D in the lungs—1,25(OH)2D3 reduces the production of inflammatory cytokines (such as IL-8) and chemokines (such as CXCL10, which promotes leukocyte recruitment) from stimulated lung epithelial cells [56].