Neuber K, Steinrücke K, Kowalzick L, Köhler I, Ring J
Department of Dermatology and Allergology, University Hospital Hamburg-Eppendorf, Germany.
Br J Dermatol. 1995 Nov;133(5):750-6. doi: 10.1111/j.1365-2133.1995.tb02750.x.
Interactions between keratinocytes and mononuclear cells via cytokines and adhesion molecules are thought to play a crucial part in inflammatory skin diseases. The cytokine-mediated effects of peripheral blood mononuclear cells (PBMC) from patients with atopic eczema (AE) and healthy individuals on keratinocytes (HaCaT) were investigated in vitro. A new coculture model (Transwell system) which consists of a lower and an upper compartment, which are separated by a polycarbonate-treated membrane, was established. 3[H]thymidine incorporation of keratinocytes and lymphocytes, as well as IL-6, IL-8 and IFN-gamma synthesis, were measured. Keratinocyte proliferation was significantly enhanced in the presence of PBMC from patients with AE. In contrast, PBMC from normal donors did not enhance HaCaT cell proliferation when they were cocultured. Lymphocytes from patients with AE showed a significantly enhanced proliferation after coculture with keratinocytes. However, PBMC from normal donors did not proliferate in the presence of HaCaT cells. Keratinocyte supernatants incubated with PBMC from either atopic or normal volunteers induced a suppression of lymphocyte 3[H]thymidine incorporation. In supernatants from cocultures of PBMC from patients with AE and keratinocytes, significantly enhanced amounts of IL-6 and IL-8, compared with normal donor's lymphocytes and HaCaT cells, were measured. No differences in IFN gamma production were observed. When PBMC were cultured without HaCaT cells, supernatants contained equal levels of IL-6, IL-8 and IFN-gamma in normal donors and in patients with AE. Interestingly, HaCaT cells spontaneously secrete measurable amounts of IL-6, IL-8 and IFN-gamma. Blocking experiments with neutralizing antibodies against these interleukins showed a complete inhibition of keratinocyte proliferation when PBMC from normal donors were used whereas the proliferative potency of PBMC supernatants from patients with AE on keratinocytes remained. Our data indicate that (i) PBMC from patients with AE stimulate keratinocyte proliferation via soluble factor(s) that are different from IL-6, IL-8 and IFN-gamma; (ii) probably, HaCaT cells spontaneously produce lymphocyte/monocyte inhibitory soluble factors and IL-6, IL-8 as well as IFN-gamma; and (iii) secretion and/or activity of keratinocyte-derived inhibitory mediators is regulated via cytokines of PBMC infiltrating inflammatory skin.
角质形成细胞与单核细胞通过细胞因子和黏附分子相互作用，被认为在炎症性皮肤病中起关键作用。体外研究了特应性皮炎（AE）患者和健康个体的外周血单核细胞（PBMC）对角质形成细胞（HaCaT）的细胞因子介导作用。建立了一种新的共培养模型（Transwell系统），该模型由上下两个隔室组成，中间由聚碳酸酯处理过的膜隔开。测量了角质形成细胞和淋巴细胞的3[H]胸苷掺入量，以及IL-6、IL-8和IFN-γ的合成量。在AE患者的PBMC存在下，角质形成细胞增殖显著增强。相比之下，正常供体的PBMC与角质形成细胞共培养时，并未增强HaCaT细胞增殖。AE患者的淋巴细胞与角质形成细胞共培养后，增殖显著增强。然而，正常供体的PBMC在HaCaT细胞存在下并不增殖。与特应性或正常志愿者的PBMC孵育的角质形成细胞上清液可抑制淋巴细胞的3[H]胸苷掺入。与正常供体的淋巴细胞和HaCaT细胞相比，AE患者的PBMC与角质形成细胞共培养上清液中IL-6和IL-8的含量显著增加。IFN-γ产生未见差异。当PBMC在无HaCaT细胞的情况下培养时，正常供体和AE患者的上清液中IL-6、IL-8和IFN-γ水平相当。有趣的是，HaCaT细胞可自发分泌可测量量的IL-6、IL-8和IFN-γ。用针对这些白细胞介素的中和抗体进行阻断实验表明，当使用正常供体的PBMC时，角质形成细胞增殖完全受到抑制，而AE患者的PBMC上清液对角质形成细胞的增殖能力仍然存在。我们的数据表明：（i）AE患者的PBMC通过不同于IL-6、IL-8和IFN-γ的可溶性因子刺激角质形成细胞增殖；（ii）可能，HaCaT细胞自发产生淋巴细胞/单核细胞抑制性可溶性因子以及IL-6、IL-8和IFN-γ；（iii）角质形成细胞衍生的抑制性介质的分泌和/或活性通过浸润炎症皮肤的PBMC的细胞因子进行调节。
