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Background Although increased accumulation of neutrophils has been noted in chronic rhinosinusitis (CRS), the function and regulation of neutrophils in CRS are largely unknown. IL-36 family cytokines may play an important role in neutrophilic inflammation. Objective This study sought to investigate the expression and function of IL-36 cytokines in CRS. Methods Quantitative RT-PCR, immunohistochemistry, immunofluorescence, and ELISA were used to investigate the expression of IL-36 cytokines and IL-36 receptor (IL-36R) in sinonasal mucosa. The expression of IL-36R on neutrophils in polyps and blood was measured by flow cytometry. Purified blood neutrophils were cultured to investigate the regulation of IL-36R expression. The cleavage of IL-36γ was detected by Western blotting. Dispersed nasal polyp cells were treated with IL-36γ with or without elastase inhibitor and dexamethasone. Results Neutrophil infiltration and expression of IL-36 cytokines and IL-36R were upregulated in both CRS with and without nasal polyps. IL-36γ was the most abundant isoform and mainly expressed by epithelial cells in CRS. Neutrophils were the principal IL-36R + cell type in polyps. IL-36R expression was almost absent in blood neutrophils and upregulated by IL-6, IL-1β, and Dermatophagoides pteronyssinus group 1. Elastase activity was increased in polyps and degraded full-length IL-36γ. Consistently, the levels of cleaved IL-36γ were increased in polyps. Full-length IL-36γ promoted the production of matrix metalloproteinase 9; IL-17A; and chemokine (C-X-C motif) ligands 1, 2, and 8 from dispersed nasal polyp cells, which was abolished by elastase inhibitor. The proinflammatory effect of IL-36γ was not suppressed by dexamethasone. Conclusions Increased production and activation of IL-36γ may act on neutrophils and further exaggerate neutrophilic inflammation in CRS.

While a variety of genetic mutations have been shown to be associated with renal cyst formation, mechanisms of renal cyst formation are largely unknown. In prior communications we described alterations in E-cadherin assembly in cultured cystic epithelial cells (Charron AJ, Nakamura S, Bacallao R, Wandinger-Ness A. J Cell Biol 149: 111–124, 2000). Using the same cell line we assayed cadherin expression by RT-PCR using primer pairs that anneal to highly conserved sequences of cadherin genes but flank informative regions of cadherins. Using this approach we found that autosomal dominant polycystic kidney disease (ADPKD) cells express cadherin 8, a neuronal cadherin with limited expression in the kidney. Immunohistochemistry confirmed cadherin 8 expression in cystic epithelia. To test the functional significance of cadherin 8 expression in renal epithelial cells, we adapted a three-dimensional collagen culture method in which HK-2 cells form tubule structures and microinjected adenovirus into the matrix space surrounding tubule structures. Adenovirus expressing cadherin 8 under the control of a tet promoter caused cyst structures to grow out of the tubules when coinjected with adenovirus expressing a tet transactivator. Microinjection of single adenovirus expressing either tet transactivator or cadherin 8 failed to cause cyst formation. When doxycycline was added to the culture, following coinjection of adenovirus, there was a dose-response reduction in cadherin 8 expression and cyst formation. Similarly, HK-2 cells transfected with Flag-tagged cadherin 8 form cysts in addition to tubular structures. HK-2 cells transfected with Flag-tagged N-cadherin do not form cysts. These data suggest that ectopic expression of cadherin 8 in renal epithelial cells is sufficient to cause the morphogenic pattern of cyst formation.

Background Autosomal dominant polycystic kidney disease (ADPKD) causes progressive loss of renal function in adults as a consequence of the accumulation of cysts. ADPKD is the most common genetic cause of end-stage renal disease. Mutations in polycystin-1 occur in 87% of cases of ADPKD and mutations in polycystin-2 are found in 12% of ADPKD patients. The complexity of ADPKD has hampered efforts to identify the mechanisms underlying its pathogenesis. No current FDA (Federal Drug Administration)-approved therapies ameliorate ADPKD progression. Results We used the de Almeida laboratory’s sensitive new transcriptogram method for whole-genome gene expression data analysis to analyze microarray data from cell lines developed from cell isolates of normal kidney and of both non-cystic nephrons and cysts from the kidney of a patient with ADPKD. We compared results obtained using standard Ingenuity Volcano plot analysis, Gene Set Enrichment Analysis (GSEA) and transcriptogram analysis. Transcriptogram analysis confirmed the findings of Ingenuity, GSEA, and published analysis of ADPKD kidney data and also identified multiple new expression changes in KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways related to cell growth, cell death, genetic information processing, nucleotide metabolism, signal transduction, immune response, response to stimulus, cellular processes, ion homeostasis and transport and cofactors, vitamins, amino acids, energy, carbohydrates, drugs, lipids, and glycans. Transcriptogram analysis also provides significance metrics which allow us to prioritize further study of these pathways. Conclusions Transcriptogram analysis identifies novel pathways altered in ADPKD, providing new avenues to identify both ADPKD’s mechanisms of pathogenesis and pharmaceutical targets to ameliorate the progression of the disease. Electronic supplementary material The online version of this article (doi:10.1186/s40246-016-0095-x) contains supplementary material, which is available to authorized users.

The microvascular wall is remarkably simple, consisting only of the endothelial lining, subjacent basal lamina, and underlying periendothelial cells. This study describes the characterization of a novel microvascular protein. This 80,000-molecular weight protein was predominantly associated with electron-lucent amorphous material in capillary basal laminae and therefore termed cablin (protein of the capillary basal lamina). Consistent with its immunolocalization to the microvasculature, cablin was synthesized and secreted by cultured endothelial cells and vascular smooth muscle cells. Furthermore, cablin expression was induced during neovascularization. The predicted amino acid sequence of cablin revealed a prevalence of polar amino acids. Accounting for the low yet significant homology to several α-helical proteins, these residues were best accommodated by secondary structure predictions that aligned the molecule into two large α-helical domains. The presence of the integrin-binding RGD tripeptide and a putative elastin-binding sequence suggest that this rodlike molecule is suited to cross-link cells and matrix constituents. In this capacity it could contribute to the mechanical strength or the angiogenic potential of the microvasculature.

Fragile X syndrome is recognized as the most common inherited cause of mental retardation in western countries. The prevalence of the fragile X syndrome in Asian populations is uncertain. We report a multi-institutional collaborative study of molecular screening for the fragile X syndrome from 1,127 Chinese mentally retarded (MR) individuals. We found that 2.8% of the Chinese MR population screened by DNA analysis had the fragile X full mutation. Our screening indicated that the fragile X syndrome prevalence was very close to that of Caucasian subjects. In addition, we found that 62.5% of fragile X chromosomes had a single haplotype for DXS548-FRAXAC1 (21-18 repeats) which was present in only 9.7% of controls. This unique distribution of microsatellite markers flanking the FMR1 CGG repeats suggests that the fragile X syndrome in Chinese populations, as in the Caucasian, may also be derived from founder chromosomes.

Batten disease, the juvenile form of neuronal ceroid lipofuscinosis, is a prevalent neuron degenerative disorder of childhood. A 1.02-kb genomic deletion in the Batten disease gene CLN3 has been determined to be a common mutation. We developed a PCR method to screen for this deletion and tested 43 Batten disease probands. We found 36% (31/86) of Batten disease chromosomes did not carry the 1.02-kb deletion. Of the three heterozygotes for the 1.02-kb deletion, a novel G-to-A missense mutation at nucleotide 1020 of the CLN3 cDNA sequence was found on two of the non-1.02-kb deletion chromosomes. The missense mutation resulted in a substitution of glutamic acid (E) by lysine (K) at position 295 (E295 K). The E295 K mutation causes a change in predicted local protein conformation. This glutamic acid is a highly conserved acidic amino acid, being present in human, mouse, dog and yeast, which suggests it may play an important role in the function of the Batten disease protein.

Autosomal dominant polycystic kidney disease (ADPKD) is associated with a variety of cellular phenotypes in renal epithelial cells. Cystic epithelia are secretory as opposed to absorptive, have higher proliferation rates in cell culture and have some characteristics of epithelial to mesenchymal transitions [1], [2]. In this communication we describe a telomerase immortalized cell line that expresses proximal tubule markers and is derived from renal cysts of an ADPKD kidney. These cells have a single detectable truncating mutation (Q4004X) in polycystin-1. These cells make normal appearing but shorter cilia and fail to assemble polycystin-1 in the cilia, and less uncleaved polycystin-1 in membrane fractions. This cell line has been maintained in continuous passage for over 35 passages without going into senescence. Nephron segment specific markers suggest a proximal tubule origin for these cells and the cell line will be useful to study mechanistic details of cyst formation in proximal tubule cells.