Cytokines in AIDS and Cancer

我们已经使用先前开发的RNA优化技术来优化IL-15细胞因子的表达，并且已经表明我们可以在小鼠和猕猴中在DNA递送后过量产生生物活性细胞因子。这一时期的一个重要结论是，表达异源二聚体IL-15的载体的DNA递送导致细胞因子的全身活性水平以及NK和T细胞增殖的增加。因此，DNA注射现在是用于在人体中递送IL-15的实用方法。我们探索了IL-15的生物学，并表明IL-15的有效生产只有通过与所谓的IL-15受体-α在同一细胞中共表达才有可能。我们还表明，先前在人类和啮齿动物中鉴定为细胞内或细胞核IL-15的第二种形式的IL-15（SSP IL-15）在与IL-15受体α共表达时也从细胞中有效分泌。这些结果为IL-15的生物学和调控提供了新的线索，并为这种细胞因子的有效生产和临床应用提供了方法。已经构建了过量产生可溶性生物活性IL-15/IL-15受体α异二聚体的细胞系，并将其用于产生体内发现的真实生物活性形式的IL-15。将从过量生产的人细胞中纯化的IL-15注射到小鼠中，并显示出生物活性。在灵长类动物中的广泛研究表明，异二聚体IL-15具有有利的药代动力学和药效学特性。异二聚体IL-15的延长的半衰期与其他细胞因子形成鲜明对比，并且与该细胞因子对免疫系统的稳态作用一致。异源二聚体IL-15已被广泛表征，并且它是高度糖基化的。IL-15由于其刺激淋巴细胞（包括CD 8和NK细胞）的生长、活化和存活的能力而受到关注。因此，IL-15已被考虑用于癌症免疫治疗和用于支持过继转移后细胞毒性细胞克隆的生长。IL-15的其他建议用途是在淋巴细胞减少症中，在NK转移后支持NK细胞生长和活化，以及作为疫苗佐剂。我们已经表明，IL-15注射加速淋巴细胞在用细胞毒性药物治疗后呈现淋巴细胞减少的小鼠中的恢复。我们已经使用优化的表达载体在动物中表达IL-12细胞因子。高效表达导致生物活性水平，其增加DNA疫苗接种后的免疫应答，从而成为我们的疫苗的重要分子佐剂。本工作建立了优化IL-12家族细胞因子（IL-12、IL-23、IL-27、IL-35）表达的方法。DNA递送后IL-27的有效表达证明了与IL-2在消除小鼠神经母细胞瘤转移中的协同作用。

We have used the previously developed technologies of RNA optimization to optimize expression of IL-15 cytokine, and have shown that we can over-produce bioactive cytokine after DNA delivery in mice and macaques. An important conclusion this period is that DNA delivery of vectors expressing heterodimeric IL-15 leads to systemically active levels of cytokine and the increased proliferation of NK and T cells. Therefore, DNA injection is now a practical method for the delivery of IL-15 in humans. We explored the biology of IL-15 and showed that efficient production of IL-15 is possible only by co-expression in the same cell with the so-called IL-15 Receptor-alpha. We also showed that a second form of IL-15 (SSP IL-15) previously identified in humans and rodents as intracellular or nuclear IL-15 is also efficiently secreted from the cells when co-expressed with the IL-15 Receptor alpha. These results shed new light in the biology and regulation of IL-15 and provide methods for the efficient production and clinical application of this cytokine. Cell lines overproducing soluble bioactive IL-15/IL-15 Receptor alpha heterodimers have been constructed and were used for the production of the authentic bioactive form of IL-15 found in the body. IL-15 purified from over-producing human cells was injected in mice and shown to be bioactive. Extensive studies in primates have shown that heterodimeric IL-15 has favorable pharmacokinetic and pharmacodynamic properties. The extended half life of heterodimeric IL-15 is in sharp contrast to other cytokines and is in agreement with the homeostatic role of this cytokine for the immune system. Heterodimeric IL-15 has been extensively characterized and it is heavily glycosylated. IL-15 is of interest due to its ability to stimulate the growth, activation and survival of lymphocytes, including CD8 and NK cells. Thus, IL-15 has been considered for cancer immunotherapy and for support of the growth of cytotoxic cell clones after adoptive transfer. Other proposed uses of IL-15 are in lymphopenia, in supporting NK cell growth and activation after NK transfer, and as vaccine adjuvant. We have shown that IL-15 injection accelerates the recovery of lymphocytes in mice rendered lymphopenic after treatment with cytotoxic drugs. We have used optimized expression vectors to express IL-12 cytokine in animals. Efficient expression results in bioactive levels, which increase immune response after DNA vaccination, thus becoming important molecular adjuvant for our vaccines. This work established methods to optimize expression of the IL-12 family of cytokines (IL-12, IL-23, IL-27, IL-35). Efficient expression of IL-27 after DNA delivery demonstrated synergy with IL-2 in the elimination of neuroblastoma metastases in mice.