Leonardi A, Radice M, Fregona I A, Plebani M, Abatangelo G, Secchi A G
Department of Ophthalmology, Institute of Physiopathological Optics, University of Padova, Italy.
Exp Eye Res. 1999 Jun;68(6):739-46. doi: 10.1006/exer.1999.0658.
Histamine, an important mast cell mediator in allergic disorders, may affect extracellular matrix production and cell growth in vernal keratoconjunctivitis (VKC). In the present study, the histamine reactivity of conjunctival fibroblasts derived from VKC patients was investigated in vitro. Conjunctival fibroblast cultures were derived from biopses of 8 tarsal VKC patients and 5 normal subjects. These cells were maintained in vitro and stimulated with different concentrations of histamine with and without H1 (clorpheniramine) and H2 (cimetidine) receptor antagonists. Comparisons were made to fibroblasts grown in the same media without histamine and to fibroblasts stimulated with just antihistamine. The effects of histamine were evaluated by: (1) the MTT test to assess cell proliferation; (2) an in vitro wound model for cell migration and (3) the measurement of procollagen I (PIP) and procollagen III (PIIIP) in supernatants for collagen production. Results showed: (1) While VKC-derived fibroblasts proliferated at a faster rate than normal cells in unstimulated media, after histamine stimulation, VKC and normal cells grew at a similar rate. Both H1 and H2 antagonists significantly inhibited (P<0.05) histamine-induced cell proliferation. (2) Histamine enhanced cell migration after wounding; this effect was inhibited only by H2 antagonism. (3) When stimulated with histamine, VKC fibroblasts produced significantly more PIP than those in control media. Furthermore, VKC-derived fibroblasts were more sensitive to histamine challenge, producing significantly more PIP than normal fibroblasts. H1 and H2 antagonists did not modify histamine-stimulated PIP production. The enhanced proliferative and productive capacity of VKC fibroblasts may be the result of a selective overgrowth of one or more fibroblast subpopulations in a chronically inflamed tissue. Histamine increased proliferation, migration and collagen production in both normal and VKC fibroblasts. Since H2 antagonism modulated both cell growth and migration, but not histamine-induced collagen production, the latter may be mediated by a different receptor. These results showed that histamine is at least partially responsible for fibroblast stimulation.
组胺是过敏性疾病中一种重要的肥大细胞介质，可能影响春季角结膜炎（VKC）的细胞外基质产生和细胞生长。在本研究中，对来源于VKC患者的结膜成纤维细胞的组胺反应性进行了体外研究。结膜成纤维细胞培养物来自8例睑板VKC患者和5例正常受试者的活检组织。这些细胞在体外培养，并用不同浓度的组胺以及有无H1（氯苯那敏）和H2（西咪替丁）受体拮抗剂进行刺激。将其与在不含组胺的相同培养基中生长的成纤维细胞以及仅用抗组胺药刺激的成纤维细胞进行比较。通过以下方法评估组胺的作用：（1）MTT试验评估细胞增殖；（2）体外伤口模型评估细胞迁移；（3）测量上清液中I型前胶原（PIP）和III型前胶原（PIIIP）以评估胶原产生。结果显示：（1）虽然在未刺激的培养基中，来源于VKC的成纤维细胞比正常细胞增殖更快，但在组胺刺激后，VKC和正常细胞以相似的速率生长。H1和H2拮抗剂均显著抑制（P<0.05）组胺诱导的细胞增殖。（2）组胺促进伤口愈合后的细胞迁移；这种作用仅被H2拮抗剂抑制。（3）当用组胺刺激时，VKC成纤维细胞产生的PIP明显多于对照培养基中的细胞。此外，来源于VKC的成纤维细胞对组胺刺激更敏感，产生的PIP明显多于正常成纤维细胞。H1和H2拮抗剂未改变组胺刺激的PIP产生。VKC成纤维细胞增殖和产生能力增强可能是慢性炎症组织中一个或多个成纤维细胞亚群选择性过度生长的结果。组胺增加正常和VKC成纤维细胞的增殖、迁移和胶原产生。由于H2拮抗剂调节细胞生长和迁移，但不调节组胺诱导的胶原产生，后者可能由不同的受体介导。这些结果表明组胺至少部分负责刺激成纤维细胞。
