Table 1.
Experimentally evidenced stimulators and receptors of immune responses in acne development.
| Stimulators | Receptors | Response cell/tissue | References |
|---|---|---|---|
| Microorganisms-related | |||
| C. acnes | TLR2, TLR4, CD14, PAR-2 |
KCs | (5–8) |
| PBMCs | (9–11) | ||
| Monocytes | (12) | ||
| CD3+ T cells | (13) | ||
| CD4+CD45R T cells | (9, 13) | ||
| Explants | (14, 15) | ||
| Sebocytes | (16, 17) | ||
| THP-1 cells | (12) | ||
| Malassezia species | PBMCs | (18) | |
| KCs | (19) | ||
| Acne lesions | (20) | ||
| Staphylococcus species | TLR2 | KCs | (21) |
| PBMCs | (11) | ||
| Acne lesions | (22, 23) | ||
| Porphyrin III | KCs | (24) | |
| Acne lesions | (25) | ||
| CAMP1 | TLR2 | KCs | (26, 27) |
| Acne lesions | (28) | ||
| Extracellular vesicles | TLR2 | KCs | (29) |
| THP-1 cells | (29) | ||
| HSP60 | KCs | (30) | |
| SCFAs | Monocytes | (31) | |
| KCs | (31) | ||
| Lipase | Acne lesions | (20, 22, 32) | |
| Lipoprotein | TLR2 | Monocytes | (33) |
| KCs | (34) | ||
| Enterotoxin B | PBMCs | (9) | |
| Lipid mediators | |||
| Oleic acid | CD36 | Sebocytes | (35) |
| Lauric acid | CD36 | Sebocytes | (35) |
| Palmitic acid | CD36 | Sebocytes | (35) |
| Squalene | KCs | (36) | |
| TREM2+ macrophages | (37) | ||
| Neuropeptides | |||
| Substance P | Sebocytes | (38, 39) | |
| CRH | CRH-R | Sebocytes | (5, 40) |
| α-MSH | MC-1R | Sebocytes | (40) |
CAMP, Christie-Atkins-Munch-Peterson; HSP, heat shock protein; SCFAs, short-chain fatty acids; CRH, Corticotropin-releasing hormone; TLR, Toll-like receptor; PAR-2, proteinase-activated receptor-2; CRH-R, corticotropin-releasing hormone receptor; α-MSH, alpha-melanocyte stimulating hormone; MC-1R, melanocortin-1 receptor; KCs, keratinocytes; PBMCs, peripheral blood mononuclear cells.