Traditional Chinese medicine for chronic atrophic gastritis: Efficacy, mechanisms and targets

Figure 3 There are five defense layers in the gastric mucosal protection system. The first layer is a barrier composed of local mucus-bicarbonate-phospholipids. The second layer is composed of epithelial cells. The third layer is the mucosal microcirculation. The fourth layer is the mucosal immune system. The fifth layer is the repair and reconstruction factors. NK cells: Natural killer cells; DC: Dendritic cells.