AS Lau, D Lehman, J Liu

Abstract

Cytokines are soluble signaling proteins responsible for cell-to-cell communication and play critical roles in many biological processes including growth and development, immunity, and hematopoiesis. In response to pathogen invasion, these pleiotropic molecules are produced by immune cells and other cells including fibroblasts and endothelia. Interaction among cytokines results in propagation of inflammation and host defense against pathogens. The biological functions of prototype cytokines including interferons, tumor necrosis factor-alpha, interleukins, and granulocyte colony stimulating factors are reviewed. With special references to children, therapeutic uses of interferon-α in viral diseases and interferon-γ in chronic granulomatous disease are discussed. The clinical applications of granulocyte/macrophage colony stimulating factors in patients with neutropenia due to cytotoxic chemotherapy, bone marrow transplantation, and congenital agranulocytosis are presented. We also examine the role of tumor necrosis factor-alpha and interleukins in the pathogenesis of septic shock and discuss the various possible strategies to suppress the undesirable effects of over-expression of proinflammatory cytokines. In summary, advances in biotechnology enable the use of interferons and colony stimulating factors to provide novel approaches to treat children and adults with viral infections, cancer, or autoimmune diseases. In addition, manipulating the cytokine systems by inhibiting the activity of proinflammatory cytokines may prove useful in the treatment of patients with sepsis.

細胞因子為細胞間信息交流的可溶性信號蛋白，其在機體生長、發育、免疫及造血等許多生理過程中起著極其重要的作用。當病原體入侵機體時，免疫細胞及其他相關細胞如纖維母細胞、內皮細胞產生細胞因子。細胞因子間相互作用可導致炎症的發生及宿主抗病原體。本文概述了干擾素、腫瘤壞死因子α、白細胞介素和粒細胞克隆刺激因子等細胞因子的生理功能，總結了干擾素α在兒科病毒性疾病，干擾素γ在兒科慢性肉芽腫病的治療作用及粒細胞/巨噬細胞克隆刺激因子在化療致中性粒細胞減少，骨髓移植和先天性粒細胞減少症等疾病中的臨床應用進展。研究了腫瘤壞死因子α和白細胞介素在感染性休克的發病機理中的作用，探討了抑制炎病性細胞因子過度表達所致副作用的各種策略。總之，隨著生物工程技術的發展，為應用干擾素及克隆刺激因子治療兒童及成人病毒感染、腫瘤及自身免疫性疾病等提供了嶄新途徑。通過抑制炎症性細胞因子活性控制細胞因子網絡可能為治療敗血症病人的有效方法。