The recombinant human IL15 protein labeled with a 6xHis tag at the N-terminus is produced in an E. coli expression system. The IL15 gene fragment (49-162aa) is first co-cloned into a high-efficiency vector with the 6xHis tag gene, followed by transformation into E. coli. Protein expression is induced with IPTG, and the recombinant IL15 protein is subsequently harvested through bacterial cell lysis. Ni-NTA affinity chromatography is employed to purify the IL15 protein by taking advantage of the 6xHis tag’s affinity for nickel ions. SDS-PAGE analysis is performed to verify the purity of the protein, revealing a purity level greater than 90%.
Human IL15 is a crucial cytokine that plays a significant role in the immune system, particularly in the development and maintenance of T cells and NK cells. It is primarily secreted by macrophages and other immune cells, and it is essential for the survival and proliferation of memory T cells, which are vital for long-term immunity [1][2]. IL15 operates through a complex receptor system, primarily involving the IL15Rα, which enhances the stability and bioactivity of IL15 [3][4]. This receptor is critical for the trans-presentation of IL15 to other immune cells, facilitating their activation and proliferation [5].
IL15 is chemotactic for NK cells, promoting their migration and recruitment to sites of infection or inflammation [6][7]. IL15 is involved in the recruitment of CD16− NK cells into the endometrium, highlighting its role in reproductive immunology [7]. Additionally, IL15 has been implicated in various pathological conditions, including autoimmune diseases and cancer, where it can enhance the cytotoxic activity of T cells against tumors [8][9][10]. Dysregulation of IL15 has been associated with several conditions, including obesity and coronary artery disease, where altered levels of IL15 and its receptor have been observed [3][11].
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