Among the <em>22</em> <em>fibroblast</em> <em>growth</em> <em>factors</em> (FGFs), FGF21 has now emerged as a key metabolic regulator. However, the mechanism whereby FGF21 mediates its metabolic actions per se remains largely unknown. Here, we show that FGF21 represses mammalian target of rapamycin complex 1 (mTORC1) and improves insulin sensitivity and glycogen storage in a hepatocyte-autonomous manner. Administration of FGF21 in mice inhibits mTORC1 in the liver, whereas FGF21-deficient mice display pronounced insulin-stimulated mTORC1 activation and exacerbated hepatic insulin resistance (IR). FGF21 inhibits insulin- or nutrient-stimulated activation of mTORC1 to enhance phosphorylation of Akt in HepG2 cells at both normal and IR condition. TSC1 deficiency abrogates FGF21-mediated inhibition of mTORC1 and augmentation of insulin signaling and glycogen synthesis. Strikingly, hepatic βKlotho knockdown or hepatic hyperactivation of mTORC1/ribosomal protein S6 kinase 1 abrogates hepatic insulin-sensitizing and glycemic-control effects of FGF21 in diet-induced insulin-resistant mice. Moreover, FGF21 improves methionine- and choline-deficient diet-induced steatohepatitis.

FGF21 acts as an inhibitor of mTORC1 to control hepatic insulin action and maintain glucose homeostasis, and mTORC1 inhibition by FGF21 has the therapeutic potential for treating IR and type 2 diabetes. (Hepatology 2016;64:425-438).

Moyamoya syndrome is a vaso-occlusive disease involving the intracranial vessels of the circle of Willis which is accompanied by an intense compensatory recruitment of new vessels. Angiogenic substances such as basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) present in the cerebrospinal fluid (CSF) have been proposed as possible mediators of the neovascular response. We analyzed CSF samples collected intraoperatively from predominantly pediatric patients with moyamoya and other conditions such as Chiari malformation (Ch), tethered cord (TC), arteriovenous malformation (AVM), brain tumor (BT) and hydrocephalus (HCP). We found that CSF bFGF was significantly elevated in patients with moyamoya (141 pg/ml, n = 37), Ch (56.7 pg/ml, n = <em>22</em>), TC (55.1 pg/ml, n = 23), AVM (354 pg/ml, n = 5), and BT (208 pg/ml, n = 5) compared to patients with HCP (5.5 pg/ml, n = 7) and controls (1.6 pg/ml, n = 25; p < 0.05). There was no dependence of CSF bFGF on patient age or gender. Although CSF bFGF in the moyamoya group showed no correlation with the Suzuki radiographic stage at either pre- or post-operative (1-year follow-up) angiography, it showed a trend with the Matsushima angiographic score with increasing collateral vascularization from the synangiosis developing at higher levels of CSF bFGF. Our findings suggest that CSF bFGF may be playing a wide-ranging role in a number of central nervous system conditions associated with ischemia and hypervascularity. Although not a specific marker for moyamoya, elevated CSF bFGF may serve as a weak predictor of the extent of angiogenesis to be expected in indirect revascularization procedures.

We quantified the mRNA expression of all <em>22</em> <em>fibroblast</em> <em>growth</em> <em>factor</em> family members (FGF) and their four receptors (FGFR) in adult mouse full-thickness skin at various stages of the hair <em>growth</em> cycle. We found that in addition to mRNA encoding FGF previously identified in skin (FGF1, 2, 5, 7, 10, 13, and <em>22</em>), FGF18 mRNA was also strongly expressed. Expression of these FGF varied throughout hair <em>growth</em> cycle: mRNA expression of FGF18 and 13 peaked at telogen; FGF7 and 10 at anagen V; and FGF5 and <em>22</em> at anagen VI. In situ hybridization revealed that FGF18 mRNA is mainly expressed in the anagen inner root sheath and telogen bulge of hair follicles. In culture, FGF18 stimulated DNA synthesis in human dermal <em>fibroblasts</em>, dermal papilla cells, epidermal keratinocytes and vascular endothelial cells. When FGF18 was administered subcutaneously to mice in a uniform telogen state, anagen hair <em>growth</em> was observed. Our findings suggest that FGF18 is important for the regulation of hair <em>growth</em> and the maintenance of skin in adult mice.

4p16.3 has previously been identified as a region of non-random LOH in transitional cell carcinoma, suggesting the presence of a tumour suppressor gene. One candidate within this region is <em>fibroblast</em> <em>growth</em> <em>factor</em> receptor 3 (FGFR3). Germline mutations in FGFR3 are known to cause several autosomal dominant skeletal dysplasias, the severity of which depends on the position and nature of the mutation in the protein. We investigated the frequency and nature of FGFR3 mutations in a panel of transitional cell carcinomas and cell lines and studied the possible link between mutation and loss of heterozygosity (LOH) on 4p16.3. FGFR3 coding sequence from 63 transitional cell carcinomas (TCC) of various stages and grades, and 18 cell lines was analysed by fluorescent SSCP. Samples with abnormal migration patterns were sequenced to identify the mutation or polymorphism. Thirty-one of the 63 tumours had previously been assessed to have LOH at 4p16.3. Twenty-six of the 63 tumours (41%) and 4/18 (<em>22</em>%) of the cell lines had missense mutations in FGFR3. All mutations detected in our panel have been reported in the germline where all apart from one cause lethal conditions. One tumour contained K652Q which has recently been identified in less severe cases of skeletal dysplasia. Tumours with and without LOH at 4p16.3 had mutations in FGFR3 suggesting that these two events are not causally linked. The frequency of FGFR3 mutation indicates that this protein plays an important role in TCC.

The homeostatic adult bone marrow (BM) is a complex tissue wherein physical and biochemical interactions serve to maintain a balance between the hematopoietic and nonhematopoietic compartments. To focus on soluble <em>factor</em> interactions occurring between mesenchymal and hematopoietic cells, a serum-free adhesion-independent culture system was developed that allows manipulation of the <em>growth</em> of both mesenchymal and hematopoietic human BM-derived progenitors and the balance between these compartments. Factorial experiments demonstrated a role for stem cell <em>factor</em> (SCF) and interleukin 3 (IL-3) in the concomitant <em>growth</em> of hematopoietic (CD45+) and nonhematopoietic (CD45-) cells, as well as their derivatives. Kinetic tracking of IL-3alpha receptor (CD123) and SCF receptor (CD117) expression on a sorted CD45- cell population revealed the emergence of CD45-CD123+ cells capable of osteogenesis. Of the total <em>fibroblast</em> colony-forming units (CFU-Fs) and osteoblast colony-forming units (CFU-O), approximately 24% of CFU-Fs and about <em>22</em>% of CFU-Os were recovered from this population. Cell-sorting experiments demonstrated that the CD45+ cell population secreted soluble <em>factors</em> that positively affect the survival and proliferation of CFU-Fs and CFU-Os generated from the CD45- cells. Together, our results provide insight into the intercellular cytokine network between hematopoietic and mesenchymal cells and provide a strategy to mutually culture both mesenchymal and hematopoietic cells in a defined scalable bioprocess.

CONCLUSIONS

A new case of familial tumoral calcinosis (FTC)/hyperostosis-hyperphosphatemia syndrome (HHS) due to a novel compound heterozygous mutation in N-acetylgalactosaminyltransferase 3 (GALNT3) and with new phenotypic findings is presented. The response in serum phosphate and fibroblast growth factor 23 (FGF23) to medical treatment is detailed. This case expands the genotype and phenotype of FTC/HHS and gives insight into its treatment and pathophysiology.

BACKGROUND

FTC and HHS are caused by mutations in FGF23, GALNT3, or KLOTHO. They are characterized by hyperphosphatemia, increased phosphate reabsorption, and elevated or inappropriately normal serum 1,25-dihydroxyvitamin D(3) (1,25-D(3)); FTC is associated with calcific masses, and HHS with diaphyseal hyperostosis.

METHODS

A 36-year-old woman presented with abnormal dental X-rays at age 12 and was hyperphosphatemic at 22. She underwent radiographic, biochemical and genetic testing, and medical treatment.

RESULTS

Serum phosphorus was 7.3 mg/dL (2.5-4.8), TmP/GFR 6.99 mg/100 mL (2.97-4.45), 1,25-D(3) 35 pg/mL (22-67). Radiographs revealed tooth anomalies, thyroid cartilage calcification, calcific masses in vertebral spaces, calcification of the interstitial septa of the soft tissue in the lower extremities, and cortical thickening of the long bones. Her total hip Z score was 1.9. C-terminus serum FGF23 was 1,210 RU/mL (20-108), but intact FGF23 was 7.4 pg/mL (10-50). DNA sequencing determined she was a compound heterozygote for mutations in GALNT3. Treatment with niacinamide and acetazolamide decreased TmP/GFR and serum phosphate, which was paralleled by a decrease in serum C-terminus FGF23.

CONCLUSIONS

This case broadens the spectrum of phenotypic and genotypic features of FTC/HHS and suggests treatments to decrease renal phosphate reabsorption in the setting of a low intact FGF23.

Caveolin-1 (cav1) is a <em>22</em>-kDa membrane protein essential to the formation of small invaginations in the plasma membrane, called caveolae. The cav1 gene is expressed primarily in adherent cells such as endothelial and smooth muscle cells and <em>fibroblasts</em>. Caveolae contain a variety of signaling receptors, and cav1 notably downregulates transforming <em>growth</em> <em>factor</em> (TGF)-beta signal transduction. In pulmonary pathologies such as interstitial fibrosis or emphysema, altered mechanical properties of the lungs are often associated with abnormal ECM deposition. In this study, we examined the physiological functions and the deposition of ECM in cav1(-/-) mice at various ages (1-12 mo). Cav1(-/-) mice lack caveolae and by 3 mo of age have significant reduced lung compliance and increased elastance and airway resistance. Pulmonary extravasation of fluid, as part of the cav1(-/-) mouse phenotype, probably contributed to the alteration of compliance, which was compounded by a progressive increase in deposition of collagen fibrils in airways and parenchyma. We also found that the increased elastance was caused by abundant elastic fiber deposition primarily around airways in cav1(-/-) mice at least 3 mo old. These observed changes in the ECM composition probably also contribute to the increased airway resistance. The higher deposition of collagen and elastic fibers was associated with increased tropoelastin and col1alpha2 and col3alpha1 gene expression in lung tissues, which correlated tightly with increased TGF-beta/Smad signal transduction. Our study illustrates that perturbation of cav1 function may contribute to several pulmonary pathologies as the result of the important role played by cav1, as part of the TGF-beta signaling pathway, in the regulation of the pulmonary ECM.

OBJECTIVE

To determine the role of insulin-like growth factor binding protein 5 (IGFBP-5) in the development of skin fibrosis in vivo, by examining the effect of overexpression of IGFBP-5 in mouse skin.

METHODS

Wild-type C57BL/6J mice were injected subcutaneously with replication-deficient serotype 5 adenovirus expressing human IGFBP-3 (Ad3), IGFBP-5 (Ad5), or no complementary DNA (cAd). Mice were killed 3, 8, or 22 days postinjection. The dermal thickness and dermal collagen bundle thickness in skin sections were measured. The deposition of collagen in the extracellular matrix (ECM) was quantified using the Sircol assay. Expression of proliferating cell nuclear antigen (PCNA) and fibronectin, as determined by immunohistochemical analysis, was used to evaluate fibroblast activation, and vimentin and alpha-smooth muscle actin (alpha-SMA) were used to evaluate the fibroblast phenotype.

RESULTS

Adenovirally expressed IGFBP was detected in dermal fibroblasts, endothelial cells, epithelial cells, and muscle bundles in Ad3- and Ad5-injected mice. Increased collagen deposition, denser dermal connective tissue, and increased collagen bundle thickness were observed in IGFBP-5-overexpressing mice. Dermal thickness and collagen bundle thickness were significantly increased in Ad5-injected mice compared with cAd- and Ad3-injected mice. Treatment with Ad5 resulted in a dose-dependent increase in dermal and collagen bundle thickness. Increased deposition of collagen and fibronectin, increased numbers of PCNA-positive fibroblasts, as well as increased numbers of vimentin- and alpha-SMA-double-positive fibroblasts were detected in the dermis of IGFBP-5-overexpressing mouse skin.

CONCLUSIONS

IGFBP-5 is a key mediator of fibrosis. IGFBP-5 mediates its profibrotic effects through fibroblast activation, increased ECM deposition, and myofibroblastic transformation of dermal fibroblasts. Overexpression of IGFBP-5 provides a novel model for studying the pathogenesis of skin fibrosis in systemic sclerosis.

OBJECTIVE

To clarify whether synovial cell proliferation indicates an imbalance in production between angiogenic growth factors and angiogenesis inhibitors in rheumatoid arthritis (RA), we investigated the production of basic fibroblast growth factor (b-FGF) and vascular endothelial growth factor (VEGF) as representative angiogenic growth factors and endostatin as a representative angiogenesis inhibitor.

METHODS

The b-FGF, VEGF, and endostatin levels in 90 samples of peripheral blood (PB) and 15 samples of joint fluid obtained from patients with RA and 30 samples of PB and 10 samples of joint fluid from patients without RA, including 20 patients with inflammatory arthritis without purulent arthritis, and 10 patients with osteoarthritis were measured by ELISA. VEGF and endostatin levels in blood samples from 22 patients with RA were measured at 2 points: before and 4 or 5 months after the commencement of medication.

RESULTS

The b-FGF and VEGF levels in the PB and joint fluid samples from patients with RA were markedly elevated compared to samples from patients without RA. In contrast, endostatin levels in PB and joint fluid samples from patients with RA were almost the same as in the samples from patients without RA. VEGF levels in blood samples obtained 4 or 5 months after the commencement of medication (combination of prednisolone 5 mg/day and disease modifying antirheumatic drugs: either bucillamine 100 mg/day or salazosulfapyridine 1,000 mg/day) were significantly decreased from 27.1 +/- 8.5 pg/ml in samples obtained before commencement of medication to 18.1 +/- 16.2 pg/ml. Endostatin levels in the corresponding samples were significantly increased, from 31.5 +/- 7.0 to 57.1 +/- 22.8 ng/ml [correction].

CONCLUSIONS

Our results reveal significant differences in b-FGF and VEGF levels in PB and joint fluid samples, but no difference in endostatin levels, between patients with RA and those without RA, suggesting that angiogenesis in RA occurs as a result of an imbalance in production between angiogenic growth factors and angiogenesis inhibitors.

BACKGROUND

Collateral growth is induced by chemical signals from the ischemic myocardium. We hypothesized that angiogenic growth factors are produced by cardiac tissue; they are diffusible, more concentrated in pericardial fluids, and are increased by myocardial ischemia.

RESULTS

With the use of an enzyme-linked immunosorbent assay, we measured the concentrations of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) in pericardial fluids of 12 patients with unstable angina (group 1) and of 8 patients with nonischemic heart diseases (group 2). The levels of protein in pericardial fluids were quite comparable between the two groups (34 +/- 2 versus 32 +/- 4 mg/mL). The concentration of bFGF in pericardial fluids in group 1 was 2036 +/- 357 pg/mL, significantly (P < .001) higher than the 289 +/- 72 pg/mL in group 2. The amount of bFGF per milligram of protein was also significantly (P < .05) higher in group 1 than in group 2 (67 +/- 15 versus 12 +/- 4 pg/mg). The concentration of VEGF in pericandial fluids tended to be higher in group 1, but the difference was statistically insignificant (39 +/- 7 versus 22 +/- 6 pg/mL). The amount of VEGF per milligram of protein was 1.2 +/- 0.3 pg/mg in group 1, similar to the 0.8 +/- 0.4 pg/mg in group 2.

CONCLUSIONS

This finding provides new evidence that bFGF plays an important role in mediating collateral growth in humans.

The high molecular weight (HMW) forms (24, <em>22</em>.5, and <em>22</em> kDa) of basic <em>fibroblast</em> <em>growth</em> <em>factor</em>-2 (FGF-2) contain an N-terminal extension responsible for their predominantly nuclear localization. These forms of FGF-2 are post-translationally modified, resulting in a 1- to 2-kDa increase in apparent molecular mass. Here we show that this post-translational modification is inhibited by methionine starvation and by the methyltransferase inhibitors 5'-deoxy-5'-methylthioadenosine (MTA) and 3-deaza-adenosine. Inhibition of the methylation-dependent modification results in a significant decrease in HMW FGF-2 nuclear accumulation, suggesting that methylation is relevant to the intracellular distribution of these forms of FGF-2. Treatment with MTA does not affect either the synthesis or the intracellular fate of another nuclear protein, the SV40 large T antigen, demonstrating that this drug does not have a generalized effect on nuclear protein accumulation. These results link HMW FGF-2 post-translational modification to its intracellular distribution.

The control of neuronal number is critical for coordinating innervation and target organ requirements. Although basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) is known to regulate neuron number in the developing embryonic cortex, its potential role during postnatal brain development remains undefined. To address this issue, the cerebellum, a site of postnatal neurogenesis, was used. Previously, we found that a single peripheral injection of bFGF in newborn rats elicited mitosis of neuronal precursors in the external germinal layer (EGL) 8 h after administration. We now define the sustained effects of bFGF treatment on postnatal granule cell production and cerebellar <em>growth</em>. Seventy-two h after a single injection of bFGF (20 ng/g) in newborn rats, the fraction of BrdU-labeled cells in the EGL increased by 46% without altering apoptotic cell number, consistent with enhanced precursor proliferation. Moreover, bFGF increased mitotically labeled cells by 100% and total cell density by 33% in the internal granular layer (IGL), the final destination of the EGL precursors. Because cerebellar volume also increased by <em>22</em>%, bFGF-induced proliferation enhanced generation of total IGL neurons and increased cerebellar <em>growth</em>. These morphometric measures were corroborated independently by using DNA quantitation: cerebellar DNA content increased 16% after bFGF injection, consistent with increased neuron number. Furthermore, using DNA quantitation as an index, increased total cerebellar cell number elicited by bFGF injection persisted beyond the neurogenetic period, until P35. We conclude that a single postnatal injection of bFGF increases granule neuron number and enhances cerebellar <em>growth</em> following mitotic stimulation.

Stromal myo<em>fibroblasts</em> (SMF) associated with various types of carcinomas are believed to emerge under the influence of the tumor cells. Recent studies have shown that SMF may originate from <em>fibroblasts</em> within the tumor stroma or even from carcinoma cells by the process of epithelial-mesenchymal transition. The aim of this study was to investigate the concomitant expression of epithelial membrane antigen and alpha-smooth muscle actin in cells at the tumor-connective tissue interface in human tongue carcinoma, as a possible reflection of epithelial-mesenchymal transition. Given its key role in this process, expression of transforming <em>growth</em> <em>factor</em>-beta in the malignant cells was assessed as well. Immunostaining with alpha-smooth muscle actin was performed on cases of hyperplasia (n = 16), mild dysplasia (n = 12), moderate-to-severe dysplasia (n = 11) and carcinoma (n = <em>22</em>). Transforming <em>growth</em> <em>factor</em>-beta assessment and double immunostaining with epithelial membrane antigen and alpha-smooth muscle actin were performed only in cases of carcinoma. SMF were significantly associated with carcinomas, while their number in pre-malignant lesions (hyperplasia and dysplasia) was significantly lower (P < 0.001). Although SMF were found in all carcinomas, they were heterogeneous in their frequency and patterns of distribution. In addition, 95% of the carcinomas expressed transforming <em>growth</em> <em>factor</em>-beta and 41% exhibited cells positive for both epithelial membrane antigen and alpha-smooth muscle actin. SMF were almost exclusively associated with established carcinomas and not with pre-malignant lesions. Cells that co-expressed epithelial membrane antigen and alpha-smooth muscle actin can be a manifestation of epithelial-mesenchymal transition and, as such, may serve as a source for SMF in these tumors. These findings appear to be linked to the frequent expression of transforming <em>growth</em> <em>factor</em>-beta by the malignant cells.

Heparin-binding EGF-like <em>growth</em> <em>factor</em> (HB-EGF) is a <em>22</em> kDa, O-glycosylated protein that is mitogenic for <em>fibroblasts</em>, smooth muscle cells (SMC) and epithelial cells. This review describes the primary structure of HB-EGF, as well as its processing. The structure of the mouse and human HB-EGF genes is also discussed. Finally, this review summarizes HB-EGF expression patterns, receptor-mediated signaling, and role in several important biological systems.

Multiple regions of the genome are often amplified during breast cancer development and progression, as evidenced in a number of published studies by comparative genomic hybridization (CGH). However, only relatively few target genes for such amplifications have been identified. Here, we indicate how small-scale commercially available cDNA and CGH microarray formats combined with the tissue microarray technology enable rapid identification of putative amplification target genes as well as analysis of their clinical significance. According to CGH, the SUM-52 breast cancer cell line harbors several high-level DNA amplification sites, including the 10q26 chromosomal region where the <em>fibroblast</em> <em>growth</em> <em>factor</em> receptor 2 (FGFR2) gene has been localized. High level amplification of FGFR2 in SUM-52 was identified using CGH analysis on a microarray of BAC clones. A cDNA microarray survey of 588 genes showed >40-fold overexpression of FGFR2. Finally, a tissue microarray based FISH analysis of 750 uncultured primary breast cancers demonstrated in vivo amplification of the FGFR2 gene in about 1% of the tumors. In conclusion, three consecutive microarray (CGH, cDNA and tissue) experiments revealed high-level amplification and overexpression of the FGFR2 in a breast cancer cell line, but only a low frequency of involvement in primary breast tumors. Applied to a genomic scale with larger arrays, this strategy should facilitate identification of the most important target genes for cytogenetic rearrangements, such as DNA amplification sites detected by conventional CGH. Figures on http://www.esacp.org/acp/2001/<em>22</em>-4/heiskanen.htm

Nerve <em>growth</em> <em>factor</em> receptor (NGFR) is a transmembrane glycoprotein without intrinsic tyrosine kinase activity, whose expression is not restricted to neural cells. NGFR is reported to act as a tumour suppressor, negatively regulating cell <em>growth</em> and proliferation. NGFR expression was immunohistochemically analysed in normal breast tissue and in 140 benign, biphasic and preinvasive breast lesions, in <em>22</em> tumours with myoepithelial differentiation and in two cohorts of breast cancer patients: a series of 245 invasive breast carcinomas studied with tissue microarrays and 37 high-grade invasive ductal carcinomas with basal-like immunophenotype. NGFR consistently displayed membrane reactivity in myoepithelial cells arranged as a continuous layer around normal ducts and lobular units, intralobular <em>fibroblasts</em>, vascular adventitia and nerve bundles. Myoepithelial cells of benign proliferations and pre-invasive lesions were consistently positive for NGFR. Scattered NGFR-positive cells were observed in solid areas of six out of nine cases of hyperplasia of usual type, whereas in flat atypia, lobular carcinoma in situ and virtually all cases of ductal carcinoma in situ (97.5%), NGFR was restricted to the myoepithelial layer. Positivity for NGFR was observed in 11 out of 245 (4.5%) breast carcinomas, nine out of 20 (45%) metaplastic breast carcinomas and 14 out of 37 (38%) basal-like breast carcinomas. NGFR expression in invasive tumours significantly correlated with that of cytokeratins 5/6 (P<0.05), 14 (P<0.0001) and 17 (P<0.0005) and EGFR (P<0.0001) and displayed an inverse correlation with oestrogen and progesterone receptors (both, P<0.0001). NGFR showed a statistically significant association with longer disease-free (P<0.05) and overall survival (P<0.01) in the cohort of patients with basal-like carcinomas. This study demonstrates the usefulness of NGFR as a new adjunct marker to identify myoepithelial cells in preinvasive lesions and myoepithelial differentiation in breast carcinomas. Furthermore, provisional data in a small number of basal-like breast carcinomas suggest that NGFR may identify a subgroup of basal-like breast carcinomas with good prognosis.

OBJECTIVE

The effect of nerve growth factor (NGF) and its receptor (NGFR) in inflammatory diseases is a novel research field. The purpose of this study was to investigate the role of NGF/NGFR in human T cell subpopulations and fibroblast-like synovial cells (FLS) and examine its pathophysiologic significance in psoriatic arthritis (PsA) and rheumatoid arthritis (RA).

METHODS

Expression of NGF/NGFR was examined in synovial fluid (SF), FLS, peripheral blood (PB)-derived T cells, and SF-derived T cells from patients with PsA, RA, and osteoarthritis (OA). NGF levels were determined by enzyme-linked immunosorbent assay. NGF-induced T cell/FLS proliferation was examined by MTT assay. Low-affinity (p75)/high-affinity (TrkA) NGFR expression was determined by high-dimensional fluorescence-activated cell sorting. A monochlorobimane assay was used to determine the effect of NGF on T cell survival.

RESULTS

Levels of NGF were higher in SF samples from PsA and RA patients as compared to SF samples from OA patients. NGF-induced FLS proliferation was more marked in PsA and RA patients. TrkA was up-regulated on activated SF T cells from PsA (mean ± SD 22 ± 6.2%) and RA (8 ± 1.3%) patients, whereas in SF samples from OA patients, TrkA+CD3+ T cells were not detectable. NGF induced the proliferation of PB T cells, induced the phosphorylation of Akt in activated T cells, and consistent with known pAkt activity, inhibited tumor necrosis factor α-induced cell death in these T cells.

CONCLUSIONS

Based on our findings, we propose a model in which NGF secreted by FLS into PsA and RA synovium promotes the survival of activated autoreactive T cells as well as FLS proliferation. Thus, NGF has the potential to sustain the chronic inflammatory cascades of arthritis of autoimmune origin.

The biological activities of several <em>growth</em> <em>factors</em>/cytokines have been shown to be modulated by binding to molecules of the extracellular matrix. Here, the interactions of PDGF (isoforms AA, BB, and AB), a potent mitogen for mesenchymal cells, with collagens were investigated. All radiolabeled PDGF isoforms specifically interacted with type I, II, III, IV, V, and VI collagens (preferential binding to types III, I, VI, and IV) and their constituent chains, either when immobilized on polystyrene or blotted to nitrocellulose. PDGF-collagen interactions were of medium affinity (KD between 4 and <em>22</em> nM) and were inhibited by different soluble collagen chains suggesting a collagenous consensus binding site(s) for the PDGF isoforms investigated. Scatchard analysis revealed molar ratios of up to 3-4 PDGF molecules bound/triple-helical (native) collagen. Biological activity of collagen-bound PDGF was demonstrated by a 1.5-3-fold stimulation of proliferation of human <em>fibroblasts</em> and mouse 3T3 cells. Furthermore, a preferential association of PDGF with the collagenous extracellular matrix of cirrhotic liver could be shown by immunostaining. Our data are in accord with previous studies that localized PDGF in the extracellular matrix of fibroproliferative lesions and suggest that binding of PDGF to collagens may localize and modulate its biological activities.

Serum levels of basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) and vascular endothelial <em>growth</em> <em>factor</em> (VEGF)--two <em>factors</em> known to promote tissue repair, <em>fibroblast</em> proliferation, and angiogenesis--were measured in Crohn's disease patients and correlated with bowel wall thickness (BWT), measured by conventional grey scale ultrasonography, and with the ileal intramural vessel flow, measured by contrast-enhanced color Doppler imaging. Serum samples were obtained from 25 patients with active Crohn's disease and <em>22</em> healthy volunteers, all sex- and age-matched. Serum bFGF and VEGF levels were measured by ELISA assay. All the patients were examined with conventional transabdominal bowel sonography. Color Doppler of the intramural enteric vessels was then performed after the intravenous injection of Levovist, a galactose-based sonographic contrast agent. In Crohn's disease patients, serum bFGF and VEGF were significantly higher compared with healthy volunteers. A positive correlation between serum bFGF and BWT and between serum VEGF and color Doppler signal intensity was found. The raised serum bFGF levels in Crohn's disease patients with intestinal strictures compared with patients with other phenotypes (fistulizing, inflammatory), together with the correlation observed between serum bFGF and BWT, suggests a possible involvement of bFGF in the process of transmural fibrogenesis in Crohn's disease. The higher levels of VEGF in those patients with increased intramural blood flow suggests that VEGF may be considered a marker of angiogenesis in this condition.

OBJECTIVE

Numerous studies have evaluated the prevalence and importance of vitamin D deficiency among patients with chronic kidney disease and end-stage renal disease; however, little is known about vitamin D levels in acute kidney injury (AKI). We evaluated the association between vitamin D metabolites and clinical outcomes among patients with AKI.

METHODS

Prospective cohort study.

METHODS

A total of 30 participants with AKI and 30 controls from general hospital wards and intensive care units at a tertiary care hospital were recruited for the study.

METHODS

Plasma levels of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)2 D], 24R,25-dihydroxyvitamin D3 , vitamin D binding protein (VDBP) and fibroblast growth factor 23 (FGF23) were measured within 24 hours of AKI onset and 5 days later. Bioavailable 25(OH)D and 1,25(OH)2 D levels, defined as the sum of free- and albumin-bound 25(OH)D and 1,25(OH)2 D, were estimated using equations.

RESULTS

Compared to controls, participants with AKI had lower levels of 1,25(OH)2 D [17 (10-22) vs 25 (15-35) pg/ml, P = 0·01], lower levels of VDBP [23 (15-31) vs 29 (25-36) mg/dl, P = 0·003] and similar levels of bioavailable 25(OH)D and 1,25(OH)2 D at enrolment. Levels of bioavailable 25(OH)D were inversely associated with severity of sepsis in the overall sample (P < 0·001). Among participants with AKI, bioavailable 25(OH)D, but not other vitamin D metabolites, was significantly associated with mortality after adjusting for age and serum creatinine (adjusted odds ratio per 1 SD ln [bioavailable 25(OH)D] = 0·16, 95% confidence interval = 0·03-0·85).

CONCLUSIONS

Bioavailable 25(OH)D could have a role as a biomarker or mediator of adverse outcomes among patients with established AKI.

OBJECTIVE

The <em>fibroblast</em> <em>growth</em> <em>factor</em> (FGF) family consists of <em>22</em> members. In rodents, several FGFs are expressed in the pancreas, where they participate in epithelial-mesenchymal interactions. Our objective was to describe the pattern of expression of FGFs in the human embryonic pancreas and to analyse their effect on pancreas development.

METHODS

The expression of FGFs was analysed by RT-PCR. To investigate the cell types expressing FGF7 and FGF10, we separated epithelial from mesenchymal cells using immunomagnetic beads linked to E-cadherin antibodies and performed real-time PCR. The effect of FGF7 and FGF10 on proliferation of human embryonic pancreatic epithelial cells was evaluated in vitro by measuring BrdU incorporation.

RESULTS

We found that different FGFs are expressed in the human embryonic pancreas, and we focused on FGF7 and FGF10. We defined a new approach to separating epithelial cells (containing the pancreatic progenitor cells) from mesenchymal cells. This allowed us to demonstrate that human embryonic pancreatic mesenchymal cells express both FGF7 and FGF10. We next demonstrated that FGF7 and FGF10 were able to induce the proliferation of the epithelial cells in vitro.

CONCLUSIONS

These findings indicate that it is now possible to efficiently separate human embryonic pancreatic epithelial from mesenchymal cells, an important step to characterize and expand progenitor cells. This method allowed us to demonstrate that human embryonic pancreatic mesenchyme expresses FGF7 and FGF10 that act on epithelial cells to activate their proliferation. Such growth factors could thus be used to expand human embryonic pancreatic epithelial cells.

<AbstractText>X-linked hypophosphataemia in children is characterised by elevated serum concentrations of <em>fibroblast</em> <em>growth</em> <em>factor</em> 23 (FGF23), hypophosphataemia, rickets, lower extremity bowing, and <em>growth</em> impairment. We compared the efficacy and safety of continuing conventional therapy, consisting of oral phosphate and active vitamin D, versus switching to burosumab, a fully human monoclonal antibody against FGF23, in paediatric X-linked hypophosphataemia.</AbstractText><AbstractText>In this randomised, active-controlled, open-label, phase 3 trial at 16 clinical sites, we enrolled children with X-linked hypophosphataemia aged 1-12 years. Key eligibility criteria were a total Thacher rickets severity score of at least 2·0, fasting serum phosphorus lower than 0·97 mmol/L (3·0 mg/dL), confirmed PHEX (phosphate-regulating endopeptidase homolog, X-linked) mutation or variant of unknown significance in the patient or a family member with appropriate X-linked dominant inheritance, and receipt of conventional therapy for at least 6 consecutive months for children younger than 3 years or at least 12 consecutive months for children older than 3 years. Eligible patients were randomly assigned (1:1) to receive either subcutaneous burosumab starting at 0·8 mg/kg every 2 weeks (burosumab group) or conventional therapy prescribed by investigators (conventional therapy group). Both interventions lasted 64 weeks. The primary endpoint was change in rickets severity at week 40, assessed by the Radiographic Global Impression of Change global score. All patients who received at least one dose of treatment were included in the primary and safety analyses. The trial is registered with ClinicalTrials.gov, number NCT02915705.</AbstractText><AbstractText>Recruitment took place between Aug 3, 2016, and May 8, 2017. Of 1<em>22</em> patients assessed, 61 were enrolled. Of these, 32 (18 girls, 14 boys) were randomly assigned to continue receiving conventional therapy and 29 (16 girls, 13 boys) to receive burosumab. For the primary endpoint at week 40, patients in the burosumab group had significantly greater improvement in Radiographic Global Impression of Change global score than did patients in the conventional therapy group (least squares mean +1·9 [SE 0·1] with burosumab vs +0·8 [0·1] with conventional therapy; difference 1·1, 95% CI 0·8-1·5; p<0·0001). Treatment-emergent adverse events considered possibly, probably, or definitely related to treatment by the investigator occurred more frequently with burosumab (17 [59%] of 29 patients in the burosumab group vs seven [<em>22</em>%] of 32 patients in the conventional therapy group). Three serious adverse events occurred in each group, all considered unrelated to treatment and resolved.</AbstractText><AbstractText>Significantly greater clinical improvements were shown in rickets severity, <em>growth</em>, and biochemistries among children with X-linked hypophosphataemia treated with burosumab compared with those continuing conventional therapy.</AbstractText><AbstractText>Ultragenyx Pharmaceutical and Kyowa Kirin International.</AbstractText>

Immobilized patterns of unmodified <em>fibroblast</em> <em>growth</em> <em>factor</em>-2 (FGF-2), with varying surface concentrations, were inkjet printed onto physiologically relevant fibrin substrates. Printed patterns were characterized using iodinated FGF-2 to determine FGF-2 surface concentration and retention of FGF-2 binding in vitro. MG-63 cells were uniformly seeded onto patterned substrates. Cells were exposed to defined spatial FGF-2 surface concentrations of 1-<em>22</em> pg/mm(2). Cell numbers were observed to increase in register with the printed FGF-2 patterns from an initial random uniform cell distribution across the patterned and non-patterned regions. Based on time-lapse image analysis, the primary organizational response of the cells was determined to be proliferation and not migration. Cell counts on and off the FGF-2 patterns over time demonstrated an increase in cell density up to a FGF-2 surface concentration of 14 pg/mm(2). Higher surface concentrations did not result in increased cell density. In addition, the cells on the FGF-2 patterns survived longer than the cells off patterns. Our inkjet printing approach permits the systematic study of cellular responses to defined spatial surface concentrations of immobilized <em>growth</em> <em>factors</em>.

Human basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (FGF-2) occurs in four isoforms: a low molecular weight (LMW FGF-2, 18 kDa) and three high molecular weight (HMW FGF-2, <em>22</em>, <em>22</em>.5, and 24 kDa) forms. LMW FGF-2 is primarily cytoplasmic and functions in an autocrine manner, whereas HMW FGF-2s are nuclear and exert activities through an intracrine, perhaps nuclear, pathway. Selective overexpression of HMW FGF-2 forms in <em>fibroblasts</em> promotes <em>growth</em> in low serum, whereas overexpression of LMW FGF-2 does not. The HMW FGF-2 forms have two functional domains: an amino-terminal extension and a common 18-kDa amino acid sequence. To investigate the role of these regions in the intracrine signaling of HMW FGF-2, we produced stable transfectants of NIH 3T3 <em>fibroblasts</em> overexpressing either individual HMW FGF-2 forms or artificially nuclear-targeted LMW FGF-2. All of these forms of FGF-2 localize to the nucleus/nucleolus and induce <em>growth</em> in low serum. The nuclear forms of FGF-2 trigger a mitogenic stimulus under serum starvation conditions and do not specifically protect the cells from apoptosis. These data indicate the existence of a specific role for nuclear FGF-2 and suggest that LMW FGF-2 represents the biological messenger in both the autocrine/paracrine and intracrine FGF-2 pathways.