Recombinant canine IL-21 protein

IL-21, also known as Interleukin-21, is an important modulator of natural killer (NK) cell function. However, little is known about IL-21 function in canine NK cells because the phenotype of these cells remains undefined. NK cells proliferated rapidly in response to activation by IL-21 for 3 weeks, and IL-21 was able to induce changes in the mRNA expression of NK cell-related receptors and enhance the effector function of NK cells in perforin- and granzyme-B-dependent manners. The duration, frequency and timing of IL-21 stimulation during culture affected the rate of proliferation, patterns of receptor expression, cytokine production, and anti-tumor activity. It has a potential predicating that synergistic interactions of IL-21 with IL-2 and IL-15 play an important role in the proliferation, receptor expression, and effector function of canine NK cells. Recombinant canine IL-21, was expressed in E. coli and purified by using conventional chromatography techniques.