Azad N, LaPaglia N, Kirsteins L, Uddin S, Steiner J, Williams D W, Lawrence A M, Emanuele N V
Research Service, Edward Hines Jr Hospital, Hines, Illinois 60141, USA.
J Endocrinol. 1997 May;153(2):241-9. doi: 10.1677/joe.0.1530241.
Jurkat cells were used to study the immunomodulatory role of luteinizing hormone-releasing hormone (LHRH) in immune cells. The Jurkat cell, a human mature leukemic cell line, phenotypically resembles resting human T lymphocytes and has been widely used to study T cell physiology. The data from this study demonstrate that the Jurkat cell concentration of immunoreactive LHRH was 210 +/- 36 pg/10(6) cells and that of proLHRH was 188 +/- 27 pg/10(6) cells (means +/- S.E.M.). The authenticity of this LHRH immunoreactivity is documented in two ways. First, both Jurkat LHRH and proLHRH immunoreactivity demonstrate dilutional parallelism with hypothalamic LHRH and proLHRH. Second, Jurkat lysates show LHRH bioactivity by releasing luteinizing hormone from rat anterior pituitary cells in culture. The presence of substantial amounts of LHRH in medium in which Jurkat cells were cultured for 72 h indicated that LHRH can be released from the cells. Using specific primers to exons 2 and 4 of the LHRH gene, we have found that Jurkat cells (like human T cells) express LHRH mRNA. The LHRH agonist, des-Gly10,D-Trp6-LHRH ethylamide, significantly increases the proliferative activity of Jurkat cells, as assessed by tritiated thymidine incorporation, from 15980 +/- 1491 c.p.m. in control to 28934 +/- 3395, 30457 +/- 3861 (P = 0.05 vs control) or 35299 +/- 5586 c.p.m. (P < 0.01 vs control) with 10(-11), 10(-9) or 10(-7) M agonist respectively. LHRH antagonist, [D-pGlu1,D-Phe2,D-Trp3,6]-LHRH, at a concentration of 10(-8) M decreases Jurkat cell proliferative activity form 17145 +/- 526 c.p.m. in control medium to 10653 +/- 1323 c.p.m. (P = 0.05). Co-incubation with the LHRH antagonist completely inhibits the proliferative stimulation induced by the LHRH agonist. Furthermore, applying monoclonal LHRH antibody to Jurkat cells inhibits the cell proliferative activity assessed by tritiated thymidine incorporation from 19900 +/- 2675 c.p.m. in control to 15680 +/- 2254, 15792 +/- 1854 and 9700 +/- 908 c.p.m. in media with 1:40, 1:20 and 1:10 dilution of purified antibody respectively (P < 0.01, 1:10 dilution compared with control). In addition, the cAMP level in LHRH-stimulated Jurkat cells is decreased to 74, 27 and 57% of control levels after 15, 30 and 45 min respectively of exposure to 10(-7) M LHRH agonist. In summary, Jurkat cells produce, process and release immunoreactive and bioactive LHRH, as do normal human T cells. Endogenous and exogenous LHRH increase Jurkat cell proliferative activity, and cAMP may be involved in LHRH-induced Jurkat cell proliferation. The Jurkat cell may be a useful model with which to study the role of LHRH in human T cell function.
使用Jurkat细胞研究促黄体生成激素释放激素（LHRH）在免疫细胞中的免疫调节作用。Jurkat细胞是一种人类成熟白血病细胞系，表型上类似于静息的人类T淋巴细胞，已被广泛用于研究T细胞生理学。本研究数据表明，Jurkat细胞中免疫反应性LHRH的浓度为210±36 pg/10⁶细胞，前体LHRH的浓度为188±27 pg/10⁶细胞（平均值±标准误）。这种LHRH免疫反应性的真实性通过两种方式得以证明。第一，Jurkat细胞的LHRH和前体LHRH免疫反应性与下丘脑LHRH和前体LHRH均呈现稀释平行性。第二，Jurkat细胞裂解物通过从培养的大鼠垂体前叶细胞中释放促黄体生成激素来显示LHRH生物活性。在Jurkat细胞培养72小时的培养基中存在大量LHRH，表明LHRH可从细胞中释放出来。使用针对LHRH基因外显子2和4的特异性引物，我们发现Jurkat细胞（如人类T细胞）表达LHRH mRNA。LHRH激动剂去甘氨酸¹⁰、D-色氨酸⁶-LHRH乙酰胺，通过氚标记胸腺嘧啶核苷掺入法评估，显著增加Jurkat细胞的增殖活性，从对照中的15980±1491 c.p.m.分别增加到10⁻¹¹、10⁻⁹或10⁻⁷ M激动剂处理后的28934±3395、30457±3861（P = 0.05，与对照相比）或35299±5586 c.p.m.（P < 0.01，与对照相比）。LHRH拮抗剂[D-焦谷氨酸¹，D-苯丙氨酸²，D-色氨酸³，⁶]-LHRH，浓度为10⁻⁸ M时，使Jurkat细胞增殖活性从对照培养基中的17145±526 c.p.m.降至10653±1323 c.p.m.（P = 0.05）。与LHRH拮抗剂共同孵育可完全抑制LHRH激动剂诱导的增殖刺激。此外，将单克隆LHRH抗体应用于Jurkat细胞，通过氚标记胸腺嘧啶核苷掺入法评估，可抑制细胞增殖活性，从对照中的19900±2675 c.p.m.分别降至纯化抗体稀释度为1:40、1:20和1:10的培养基中的15680±2254、15792±1854和9700±908 c.p.m.（P < 0.01，1:10稀释度与对照相比）。另外，在暴露于10⁻⁷ M LHRH激动剂15、30和45分钟后，LHRH刺激的Jurkat细胞中的cAMP水平分别降至对照水平的74%、27%和57%。总之，Jurkat细胞与正常人类T细胞一样，能产生、加工和释放免疫反应性和生物活性LHRH。内源性和外源性LHRH均可增加Jurkat细胞的增殖活性，且cAMP可能参与LHRH诱导的Jurkat细胞增殖。Jurkat细胞可能是研究LHRH在人类T细胞功能中作用的有用模型。
