Fig. 1: Immunohistochemistry of C5a, C5aR1, and C5aR2 expression in resected human PDAC tissues.

a High C5a expression in human PDAC cell cytoplasm (n = 90). Original magnification: ×200. b Low C5a expression in human PDAC cell cytoplasm (n = 40). Original magnification: ×200. c High C5aR1 expression in human PDAC cell cytoplasm (n = 62). Original magnification: ×200. d Low C5aR1 expression in human PDAC cell cytoplasm (n = 68). Original magnification: ×200. e High C5aR2 expression in human PDAC cell cytoplasm (n = 102). Original magnification: ×200. f Low C5aR2 expression in human PDAC cell cytoplasm (n = 28). Original magnification: ×200. g–i Images of the immunofluorescence (IF) staining of DAPI (blue), C5a (green), and C5aR1 (red) expression in the human PDAC cytoplasm. C5a and C5aR1 are expressed in the PDAC cell cytoplasm, and margin sites were observed (arrowheads). Original magnification: ×200. j–l Images of IF staining of DAPI (blue), C5a (green), and C5aR2 (red) expression in the human PDAC cytoplasm. C5a and C5aR2 are expressed in the PDAC cell cytoplasm, and margin sites were observed (arrowheads). Original magnification: ×200. m Kaplan–Meier analyses for OS of PDAC patients based on PDAC cell cytoplasmic C5a-C5aR1 axis (C5a-C5aR1 c-axis). The high C5a-C5aR1 c-axis group presented significantly shorter OS (p = 0.0078, log-rank test) than low C5a-C5aR1 c-axis group. n Kaplan–Meier analyses for OS of PDAC patients based on PDAC cell cytoplasmic C5a-C5aR2 axis (defined: C5a-C5aR2 c-axis). The Low C5a-C5aR2 c-axis group presented significantly shorter OS (p = 0.049, log-rank test) than the High C5a-C5aR2 c-axis group. o Kaplan–Meier analyses for OS of PDAC patients based on PDAC cell cytoplasmic C5a-C5aR1 c-axis and C5a-C5aR2 c-axis combination. The high C5a-C5aR1 c-axis and low C5aR2 c-axis group presented significantly shorter OS than other groups (p = 0.0001, log-rank test).