Fig 1: The distribution of NLRP1, NLRP2, NLRP3, NLRP6, NLRP12, and absent in melanoma 2 (AIM2) in the gingival epithelium and lamina propria of healthy and periodontitis patients. Full-thickness gingival tissue specimens including both the epithelium and connective tissue were obtained from healthy subjects (n = 5) and patients with severe chronic periodontitis (n = 5). Samples were fixed in 10% formalin for immunohistochemistry assays to detect the expression of NLRP1, NLRP2, NLRP3, NLRP6, NLRP12, and AIM2 (P: periodontitis specimens, n = 5; H: healthy gingiva, n = 5; arrows: positive stain; and magnification: 400×). *p < 0.05, **p < 0.01, and ***p < 0.001.