Immunohistochemical expression of growth factors in subacute thyroiditis and their effects on thyroid folliculogenesis and angiogenesis in collagen gel matrix culture.
The inflammatory-mechanistic basis of subacute thyroiditis remains unclear. To elucidate the roles of vascular endothelial cell growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor-BB (PDGF), transforming growth factor-beta1 (TGF-beta1) and epidermal growth factor (EGF) in the inflammatory process, their immunoexpression was examined in biopsy specimens of ten cases. At the granulomatous stage, all cases expressed VEGF, bFGF, PDGF, and TGF-beta1 in monocytes/macrophages infiltrating into follicle lumina, and in both epithelioid histiocytes and multinucleated giant cells of the granulomas. In fibroblasts and endothelial cells around the granulomas, all cases displayed VEGF, bFGF, and PDGF, but TGF-beta1 was detected only in fibroblasts in two cases. No cases expressed EGF in any of the above cell types. At the regenerative stage, all cases expressed VEGF, bFGF, and EGF in regenerating thyrocytes, whereas three and no cases displayed PDGF and TGF-beta1, respectively. Ten, seven and six cases expressed PDGF in fibroblasts, endothelial cells, and monocytes, respectively. In these cell types, all cases expressed VEGF and bFGF, whereas no cases displayed TGF-beta1 and EGF. To estimate the roles of these growth factors in thyroid tissue regeneration, their effects on thyroid folliculogenesis and angiogenesis were examined using collagen gel culture of thyrocytes and endothelial cells, respectively. Cell proliferation was also studied by bromodeoxyuridine (BrdU) uptake. EGF decreased follicle formation and TGF-beta1 drastically inhibited it, but the others had no effect. VEGF showed the greatest effect on vessel formation, although all of the others promoted it. EGF and VEGF or bFGF caused the highest BrdU uptake in thyrocytes and endothelial cells, respectively. The data suggest firstly, that at the granulomatous stage of subacute thyroiditis, growth factor-rich monocytes/macrophages infiltrating into follicle lumina trigger the granulomatous reaction, and VEGF, bFGF, PDGF, and TGF-beta1 produced by the stromal cell types tested mediate the reaction; secondly, that at the regenerative stage, EGF serves follicle regeneration through its mitogenic effect on thyrocytes, although some cofactors with EGF are involved in folliculogenesis and the decreased expression of TGF-beta1, a fibrogenic factor, contributes to thyroid tissue repair; and thirdly, that VEGF and bFGF are more responsible for the angiogenesis at both stages than the other factors studied.
Toda S
，Nishimura T
，Yamada S
，Koike N
，Yonemitsu N
，Watanabe K
，Matsumura S
，Gärtner R
，Sugihara H
... -
《JOURNAL OF PATHOLOGY》
The mRNA expression of cytokines and their receptors in cultured iris pigment epithelial cells: a comparison with retinal pigment epithelial cells.
It has been suggested that human iris pigment epithelial (IPE) cells isolated from iridectomized tissue could be used as autologous cells for transplantation into the subretinal space in diseases with dysfunctional retinal pigment epithelium (RPE). RPE cells synthesize a number of cytokines and their receptors which are important for its proper function. Nearly nothing is known about the capacity of IPE to synthesize cytokines or responding to them. To compare the mRNA expression of 36 cytokines or their receptors in cultured adult IPE cells and RPE cells we used semi-quantitative reverse transcription polymerase chain reactions (RT-PCR). Included in our assay were cytokines with known expression in RPE to get a broad basis for comparing IPE cells: basic fibroblast growth factor (bFGF or FGF-2), and one of its receptor (FGFR-1), epidermal growth factor (EGF), and its receptor EGF-R, transforming growth factor beta(TGFbeta), and its type III receptor TGFbeta-R3, the platelet-derived growth factors and receptors (PDGF A, PDGF B, PDGF-Ralpha, PDGF-Rbeta), tumor necrosis factor alpha(TNFalpha), and two receptors TNF-R1 and TNF-R2, insulin (INS) with receptor INS-R, insulin-like growth factors (IGF1, IGF2), and receptors (IGF1-R, IGF2-R), vascular endothelial growth factor (VEGF), and two receptors (VEGF-R1 or FLT-1 and VEGF-R2 or FLK-1), the receptor for VEGF-C: VEGF-R3 or FLK-4, interleukin 6 (IL6), and its receptor (IL6-R), nerve growth factor (NGF), interleukin 1alpha(IL1alpha), and a receptor (IL1-R). In addition, cytokines or their receptors not known to be expressed in RPE were included to widen our picture of cytokine gene expression in the eye: stem cell factor (SCF), its receptor (SCF-R), low-affinity nerve growth factor receptor p75 (p75(NGF-R), ciliary neutrothropic factor (CNTF), and its receptor (CNTF-R), glycoprotein 130 interleukin 6 transducer (gp130 (IL6-SD), leukemia inhibitory factor (LIF), and its receptor (LIF-R). Semi-quantitative expression data were obtained using series of fivefold dilutions of each cDNA and a fixed number of PCR cycles. The expression of RPE 65, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and beta2-microglobulin (B2MG) was used as a control for cellular origin, RNA quality and PCR conditions. With the exception of insulin and tumor necrosis factor alphaall other cytokines analysed and their receptors were expressed in both IPE and RPE cells, even though the levels varied. No qualitative or quantitative difference were observed in the mRNA expression level of 34 (94%) of the cytokines or receptors between IPE and RPE. In contrast, the mRNA expression level of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 [VEGF-RS (FLK-1)] was lower in IPE than in RPE cells. As an increased expression of VEGF in the RPE in maculae with age-related macular disease could be involved in its pathogenesis, a decreased expression of angiogenic growth factors in IPE cells could possibly be beneficial for the therapy of age-related maculopathy if indeed other tasks of non-functional RPE cells could be performed by IPE cells. The similarity of the mRNA expression pattern in 94% of the cytokines analyzed supports the assumption that IPE cells potentially can perform functions of RPE cells in the appropriate environment.
Kociok N
，Heppekausen H
，Schraermeyer U
，Esser P
，Thumann G
，Grisanti S
，Heimann K
... -
《EXPERIMENTAL EYE RESEARCH》
ResearchGate
(全网免费下载)
钛学术
(全网免费下载)
