Transcriptional regulators dictate innate lymphoid cell fates

Research on innate lymphoid cells (ILC) has recently been a fast paced topic of immunological research. As ILCs are able to produce signature Th cytokine, ILCs have garnered considerable attention and have been described to represent the innate counterpart of the CD4 T helper (Th) cells. The development and function of ILCs are precisely regulated by a network of crucial transcription factors, which are also involved in the development or differentiation of conventional natural killer (cNK) cells and T cells. In this review, we will summarize the key transcriptional regulators and their functions through each phases of ILC development. With the phase of ILC lineage commitment, we will focus in particular on the roles of the transcription regulators Id2 and GATA-3, which in collaboration with other transcriptional factors, are critically involved in the generation of ILC fate determined progenitors. Once an ILC lineage has been established, several other transcription factors are required for the specification and functional regulation of distinct mature ILC subsets. Thus, a comprehensive understanding of the interactions and regulatory mechanisms mediated by these transcription factors will help us to further understand how ILCs exert their helper-like functions and bridge the innate and adaptive immunity.

Increased expression of ID2, PRELP and SMOC2 genes in patients with endometriosis

Endometriosis is a benign, estrogen-dependent disease with symptoms such as pelvic pain and infertility, and it is characterized by the ectopic distribution of endometrial tissue. The expression of the ID2, PRELP and SMOC2 genes was compared between the endometrium of women without endometriosis in the proliferative phase of their menstrual cycle and the eutopic and ectopic endometrium of women with endometriosis in the proliferative phase. Paired tissue samples from 20 women were analyzed: 10 from endometrial and peritoneal endometriotic lesions and 10 from endometrial and ovarian endometriotic lesions. As controls, 16 endometrium samples were collected from women without endometriosis in the proliferative phase of menstrual cycle. Analysis was performed by real-time polymerase chain reaction (PCR). There was no significant difference between gene expression in the endometrium of women with and without endometriosis. The ID2 gene expression was increased in the most advanced stage of endometriosis and in ovarian endometriomas, the PRELP was more expressed in peritoneal lesions, and the SMOC2 was highly expressed in both peritoneal and endometrioma lesions. Considering that the genes studied participate either directly or indirectly in cellular processes that can lead to cell migration, angiogenesis, and inappropriate invasion, it is possible that the deregulation of these genes caused the development and maintenance of ectopic tissue.

Id2 regulates the proliferation of squamous cell carcinoma in vitro via the NF-κB/Cyclin D1 pathway / 癌症

Squamous cell carcinoma(SCC) is a significant cause of cancer morbidity and mortality worldwide, with an incidence of up to 166 cases per 100 000 population. It arises in the skin, upper aerodigestive tract, lung, and cervix and affects more than 200 000 Americans each year. We report here that a microarray experiment comparing 41 SCC and 13 normal tissue specimens showed that Id2, a gene that controls the cell cycle, was significantly up-regulated in SCC. Enforced expression of Id2 in vitro stimulated the proliferation of SCC cells and up-regulated the transcription of nuclear factor kappa B (NF-κB) and cyclin D1. Enhancement of the NF-κB activity with p65 significantly increased the cell proliferation and the transcription of cyclin D1, whereas inhibition of the NF-κB activity with I kappa B alpha mutant (IκBαM) and pyrroline dithiocarbamate (PDTC) abrogated cell proliferation and transcription of cyclin D1. Furthermore, a mutated NF-κB binding site in the cyclin D1 promoter fully abrogated the Id2-induced transcription of cyclin D1. Taken together, these data indicate that Id2 induces SCC tumor growth and proliferation through the NF-κB/cyclin D1 pathway.

Co-culture with microglia promotes neural stem cells differentiation into astrocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Neural stem cells (NSCs) are a self-renewing and multipotent population of the central nervous system (CNS), which are active during development and maintain homeostasis and tissue integrity throughout life. Microglias are an immune cell population resident in the CNS, which have crucial physiological functions in the developing and adult CNS. This study aimed to investigate that whether microglia co-cultured with NSCs could promote astrogliogenesis from NSCs.</p><p><b>METHODS</b>Microglia and NSCs were co-cultured in 24-well insert plates. NSCs were plated in the bottom of the well and microglia in the insert. Fluorescent staining, Western blotting and RT-PCR were used to determine the effect of microglia on NSCs differentiation.</p><p><b>RESULTS</b>Co-culture of microglia and NSCs promoted astrogliogenesis from NSCs. Several key genes, such as Notch 1, Notch 2, Notch 3, Hes 5, and NRSF were downregulated, while the critical genes Id1 and Id2 were upregulated. BMP2 and FGF2 were upregulated.</p><p><b>CONCLUSION</b>Microglias act as a regulator of NSCs astrogliogenesis.</p>

Expression of human Id-2 gene in Escherichia coli and preparation of the antisera against human Id-2 / 南方医科大学学报

<p><b>OBJECTIVE</b>To express the fusion protein of glutathione S-transferase (GST) and human Id-2 in E. coli and prepare the polyclonal antibodies against Id-2.</p><p><b>METHODS</b>The coding sequence of Id-2 gene was amplified by RT-PCR from the total RNA of breast cancer tissue. The recombinant plasmid was identified by PCR, restriction endonuclease digestion analysis and sequencing. The fusion protein GST-Id-2 expressed in E. coli following IPTG induction was purified by glutathione-agarose affinity chromatography and used to immunize rabbits to prepare the polyclonal antibodies against GST-Id-2.</p><p><b>RESULTS</b>PCR, restriction endonuclease digestion and sequence analyses showed that the Id-2 gene had been correctly inserted into pGEX-6P-1 vector, and the GST-Id-2 fusion protein expressed had a relative molecular mass of approximately 40,000 as shown by SDS-PAGE. The polyclonal antibodies obtained from the rabbit sera were found to specifically react with purified Id-2 by Western blotting, ELISA and agar gel immunodiffusion (AGP).</p><p><b>CONCLUSION</b>The prepared polyclonal antibodies against Id-2 allow effective Id-2 detection and facilitate further investigation of the structure and antigen epitope of Id-2.</p>

Regulation of Inhibitors of Differentiation Family Proteins by Thyroid-Stimulating Hormone in FRTL-5 Thyroid Cells

Members of the inhibitors of differentiation (Id) family of helix-loop-helix (HLH) proteins are known to play important roles in the proliferation and differentiation of many cell types. Thyroid-stimulating hormone (TSH) regulates proliferation and differentiation by activating TSH receptor (TSHR) in thyrocytes. In this study, we found that Id2, one of the Id family proteins, is a major target for regulation by TSH in FRTL-5 thyroid cells. TSH rapidly increases the Id2 mRNA level in FRTL-5 thyroid cells but the Id2 protein showed biphasic regulatory patterns, being transiently reduced and subsequently induced by TSH treatment. Transient reduction of Id2 protein was noted within 2 hr of TSH treatment and was mediated by proteasomal degradation. Moreover, reduced Id2 expression correlated with the activity of the phosphatidylinositol 3 kinase pathway, which is activated by TSH. Although TSH increases the activity of the Id2 promoter, TSH-induced activation of this promoter was independent of c-Myc. Id2 did not alter TTF-1- and Pax-8-mediated effects on the regulation of the Tg promoter. Thus, in summary, we found that TSH regulates Id2 expression, but that Id2 does not alter the expression of thyroid-specific genes, such as Tg, in FRTL-5 thyroid cells.

Relationship between the effect of vascular endothelial growth factor on epithelial-mesenchymal transition of HK-2 cells and the expressions of bone morphogenetic protein-7 and inhibitor of DNA binding/differentiation / 中国医学科学院学报

<p><b>OBJECTIVE</b>To examine the relationship between effect of vascular endothelial growth factor (VEGF) on epithelial-myofibroblast transition (EMT) of HK-2 cells and changes in expressions of bone morphogenetic protein-7 (BMP-7) and inhibitor of DNA binding/differentiation (Id) 2, Id3.</p><p><b>METHODS</b>The cultured HK-2 cells were co-treated with transforming growth factor-beta1 (TGF-beta1) (5 ng/ml) and VEGF165 (0.1, 1, 10, 100 ng/ml), or with TGF-beta1 (5 ng/ml) and VEGF receptor-1 neutralized antibody (10 microg/ ml), and were also co-treated with TGF-beta1 (5 ng/ml) and VEGF165 (100 ng/ml) with or without activin receptor-like kinase 6 (Alk6)/Fc Chimera (2 microg/ml, to neutralize endogenous BMP-7) for 48 hours. mRNA and protein expressions of alpha-smooth muscle actin (alpha-SMA), E-cadherin, BMP-7, Id2 and Id3 of HK-2 cells were assessed with double-stain immunocytochemistry, real-time PCR and Western blot respectively.</p><p><b>RESULTS</b>Compared with normal controls, alpha-SMA expression significantly increased, while E-cadherin, BMP-7, Id2, and Id3 mRNA and protein expressions markedly decreased in HK-2 cells treated with TGF-beta1 (5 ng/ml) (P < 0.05). VEGF165 interrupted TGF-beta1 induced alpha-SMA expression in a dose-dependent manner and upregulated BMP-7, Id2 mRNA and protein expressions of the cells (P < 0.05). alpha-SMA expression increased, while E-cadherin, BMP-7, and Id2 expressions decreased further in HK-2 cells co-treated with TGF-beta1 and VEGFR1 antibody compared with normal controls (P < 0.05). When endogenous BMP-7 was neutralized with Alk6/Fc Chimera in the cells co-treated with TGF-beta1 and VEGF165, alpha-SMA expression upregulated (P < 0.05), while Id2 was not changed.</p><p><b>CONCLUSIONS</b>VEGF165 may partially inhibit TGF-beta1-induced EMT of HK-2 cells in vitro. This effect is related to the upregulated expressions of BMP-7 and Id2. Id2 may be upregulated directly by VEGF165, but not related to BMP-7.</p>

Expressions of Id-1 and Id-2 in Hyperplastic Thyroid Tissue and Thyroid Carcinoma

BACKGROUND: Id proteins are a family of helix-loop-helix proteins and are regarded to be negative regulators of cell differentiation. In general, Id-1 and Id-2 expressions are upregulated during tumor development and progression in a variety of neoplasms, and these expressions may be associated with aggressive tumor behavior. However, little is known about the roles of Id-1 and Id-2 in thyroid neoplasms. METHODS: The expressions of Id-1 and Id-2 were assessed immunohistochemically in 310 normal, hyperplastic, and neoplastic thyroid tissues using tissue microarrays. RESULTS: Normal thyroid tissues rarely expressed Id-1 or Id-2. Moreover, whilst Id-1 expression was more elevated in malignant thyroid tissue than in hyperplastic thyroid tissue, Id-2 expression was more variable. No significant differences were observed between histologic subtypes of thyroid carcinomas with respect to Id-1 or Id-2 expression. Follicular adenomas showed higher expressions of Id-1 and Id-2 than thyroid carcinomas. No significant association was found between clinicopathological parameters and Id-1 expression, though Id-2 expression was significantly reduced in metastatic, stage IV tumors. CONCLUSION: The expressions of Id-1 and Id-2 were elevated in hyperplastic and neoplastic thyroid tissues. However, neither appears suitable as a marker of malignancy or an aggressive phenotype, although Id-2 expression in advanced thyroid carcinomas may reflect a favorable prognosis.