Cathepsin S is a protein that in humans is encoded by the CTSS gene. Transcript variants utilizing alternative polyadenylation signals exist for this gene. Cathepsin S is a member of the peptidase C1 family of cysteine cathepsins, a lysosomal cysteine protease that may participate in the degradation of antigenic proteins to peptides for presentation to the MHC class II. Cathepsin S can function as an elastase over a broad pH range in alveolar macrophages. Cathepsin S is a lysosomal enzyme that belongs to the papain-like protease of cysteine proteases. While a role in antigen presentation has long been recognized, it is now understood that cathepsin S has a role in itch and pain, or nociception . The nociceptive activity results from cathepsin S functioning as a signaling molecule via activation of protease-activated receptors 2 and 4 members of the G-protein coupled receptor family.
Background References
1. Dheilly E et al. Cathepsin S Regulates Antigen Processing and T Cell Activity in Non-Hodgkin Lymphoma. Cancer Cell. 2020 May
2. McDowell SH et al. Leading the invasion: The role of Cathepsin S in the tumour microenvironment. Biochim Biophys Acta Mol Cell Res. 2020
Western blot analysis of Cathepsin S on different lysates with Rabbit anti-Cathepsin S antibody (HA724726) at 1/5,000 dilution.
Lane 1: THP-1 (Human acute monoblastic leukemia cell) cell lysate
Lane 2: THP-1 treated with 80nM TPA for 24 hours, then treated with 100ng/mL LPS and 1μg/mL BFA for 7 hours cell lysate
Lane 3: RPMI8226 (Human multiple myeloma cell) cell lysate
Lane 4: A549 (Human lung adenocarcinoma cell) cell lysate
Lane 5: MCF7 (Human breast cancer cell) cell lysate
Lysates/proteins at 15 µg/Lane.
Exposure time: 46 seconds; ECL: K1801
Low expression of Cathepsin S protein in A549 or MCF7 cells is consistent with the predicted expression pattern.
Blocking: 5% NFDM/TBST, 1 hour at room temperature
Primary antibody: HA724726, 1/5,000 in primary antibody dilution buffer (K1803), overnight at 4 °C
Secondary antibody: Goat anti-Rabbit IgG-HRP (HA1001), 1/50,000 in 5% NFDM/TBST, 1 hour at room temperature
Predicted band size: 37 kDa
Observed band size: 37, 25 kDa
Please note: All products are "FOR RESEARCH USE ONLY AND ARE NOT INTENDED FOR DIAGNOSTIC OR THERAPEUTIC USE"