Renal cell carcinoma in tuberous sclerosis complex

Renal cell carcinoma (RCC) occurs in 2% to 4% of patients with tuberous sclerosis complex (TSC). Previous reports have noted a variety of histologic appearances in these cancers, but the full spectrum of morphologic and molecular features has not been fully elucidated. We encountered 46 renal epithelial neoplasms from 19 TSC patients and analyzed their clinical, pathologic, and molecular features, enabling separation of these 46 tumors into 3 groups. The largest subset of tumors (n=24) had a distinct morphologic, immunologic, and molecular profile, including prominent papillary architecture and uniformly deficient succinate dehydrogenase subunit B (SDHB) expression prompting the novel term "TSC-associated papillary RCC (PRCC)." The second group (n=15) were morphologically similar to a hybrid oncocytic/chromophobe tumor (HOCT), whereas the last 7 renal epithelial neoplasms of group 3 remained unclassifiable. The TSC-associated PRCCs had prominent papillary architecture lined by clear cells with delicate eosinophilic cytoplasmic thread-like strands that occasionally appeared more prominent and aggregated to form eosinophilic globules. All 24 (100%) of these tumors were International Society of Urological Pathology (ISUP) nucleolar grade 2 or 3 with mostly basally located nuclei. Tumor cells from 17 of 24 TSC-associated PRCCs showed strong, diffuse labeling for carbonic anhydrase IX (100%), CK7 (94%), vimentin (88%), and CD10 (83%) and were uniformly negative for SDHB, TFE3, and AMACR. Gains of chromosomes 7 and 17 were found in 2 tumors, whereas chromosome 3p deletion and TFE3 translocations were not detected. In this study, we reported a sizable cohort of renal tumors seen in TSC and were able to identify them as different morphotypes, which may help to expand the morphologic spectrum of TSC-associated RCC

Producing Human Therapeutic Proteins in Plastids

Plastid transformation technology is set to become a major player in the production of human therapeutic proteins. Protein expression levels that can be achieved in plant plastids are hundreds of times greater than the expression levels generally obtained via nuclear transformation. Plastids can produce human proteins that are properly folded and are biologically active. Effective protein purification strategies and strategies that can achieve inducible plastid gene expression are being developed within the system. Plastid transformation technology has been extended to edible plant species, which could minimize down-stream processing costs and raises the possibility of “edible protein therapies”. The system is limited by the fact that plastid-produced proteins are not glycosylated and that, at the moment, it can be difficult to predict protein stability within the plastid. The high level of protein expression that can be obtained in plastids could make it possible to produce high-value therapeutic proteins in plants on a scale that could be accommodated in contained glasshouse facilities and still be economically viable. Growing plastid-transformed plants under contained conditions, and coupled with the level of bio-safety conferred by maternal inheritance of plastid transgenes, would address many of the social and environmental concerns relating to plant based production of human therapeutic proteins

Follicular exclusion of autoreactive B cells requires FcRIIb

In non-autoimmune mice, the 3H9 transgenic Ig heavy chain can pair with endogenous Igl1 light chains to generate B cells with specificity for DNA. These autoreactive cells are actively regulated in vivo, as indicated by the exclusion of l1 cells from the splenic B cell follicle and the absence of auto-antibody production. To study the role of Fcg receptor IIb (FcgRIIb) in peripheral B cell tolerance, FcgRIIb 2/2 mice were crossed with C57BL/6 mice bearing a site-directed knock-in of the 3H9 transgene. 3H9FcgRIIb 2/2 mice become autoreactive, lose the follicular exclusion of anti-DNA B cells and instead have l1 B cells located within splenic germinal centers. They have increased frequencies of splenic auto-antibody-producing cells and elevated titers of IgG anti-DNA auto-antibody. The data implicate an FcgRIIb-dependent checkpoint that can exclude autoreactive B cells from splenic follicles. By restricting their participation in germinal center reactions, this putative checkpoint helps attenuate the production of potentially pathogenic auto-antibodies. The data further suggest that this FcgRIIb-dependent regulation is B cell autonomous

Bilateral native nephrectomy reduces systemic oxalate level after combined liver-kidney transplant: A case report

Primary hyperoxaluria type 1 (PH1) is a rare liver enzymatic defect that causes overproduction of plasma oxalate. Accumulation of oxalate in the kidney and subsequent renal failure are fatal to PH1 patients often in pediatric age. Combined liver and kidney transplantation is the therapy of choice for end-stage renal disease due to PH1. Levels of plasma oxalate remain elevated for several months after liver transplantation, as the residual body oxalate is slowly excreted. Patients with persistent hyperoxaluria after transplant often require hemodialysis, and accumulation of residual oxalate in the kidney can induce graft dysfunction. As the native kidneys are the main target of calcium oxalate accumulation, we postulated that removal of native kidneys could drastically decrease total body oxalate levels after transplantation. Here, we report a case of bilateral nephrectomy at the time of combined liver-kidney transplantation in a pediatric PH1 patient. Bilateral nephrectomy induced a rapid decrease in plasma oxalate to normal levels in less than 20 days, compared to the several months reported in the literature. Our results suggest that removal of native kidneys could be an effective strategy to decrease the need for hemodialysis and the risk of renal dysfunction after combined liver-kidney transplantation in patients with PH1

WTA immunization reduces MW2 CA-MRSA infection in WT mice while no difference is seen in the absence of MBL.

<p>(2A) Abscess formation. Mice immunized with PBS control or WTA were infected 20 days after the last immunization. Abscess formation was examined on day 10 following systemic infection with MW2 CA-MRSA as detailed in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0069739#s2" target="_blank">Materials and Methods</a>. Abscess formation is expressed as numbers of mice with abscess and total mice in each group. * indicates p<0.0001 against all other groups (Likelihood Ratio). (2B) Bacterial load in the kidney. Bacterial titers were measured in homogenates of two combined kidneys and are expressed as cfu/g of kidneys in a box plot. Numbers of mice used are as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0069739#pone-0069739-g002" target="_blank">figure 2A</a>. * and ** indicates p<0.05 and p<0.001, respectively compared to WT immunized with PBS control (Nonparametric comparisons for each pair by Wilcoxon methods).</p

Abscess formation in systemic MRSA infection.

*<p>indicates p<0.0001 (Likelihood ratio) compared to WT in MW2 CA-MRSA infection.</p

Serum from WTA-immunized mice inhibits bacterial growth in whole blood assays <i>ex vivo</i>.

<p>Two MRSA strains, COL HA-MRSA (4A and 4B) and MW2 CA-MRSA, (4C and 4D) were used. Bacteria were incubated with whole blood from MBL KO (4A and 4C) or WT mice (4B and 4D) with serum from MBL KO mice immunized with either PBS control or WTA, as described in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0069739#s2" target="_blank">Materials and Methods</a>. Bacterial titers are expressed as mean <b>±</b> SD in each group of four samples. Each sample was measured in duplicate and the average measurement was used for statistical analysis. Representative results from two repeated experiments are shown. *, **, and *** indicate p<0.05, 0.001, and 0.0001 (Student's t-test), respectively.</p

αv Integrins combine with LC3 and atg5 to regulate Toll-like receptor signalling in B cells

Integrin signalling triggers cytoskeletal rearrangements, including endocytosis and exocytosis of integrins and other membrane proteins. In addition to recycling integrins, this trafficking can also regulate intracellular signalling pathways. Here we describe a role for αv integrins in regulating Toll-like receptor (TLR) signalling by modulating intracellular trafficking. We show that deletion of αv or β3 causes increased B-cell responses to TLR stimulation in vitro, and αv-conditional knockout mice have elevated antibody responses to TLR-ligand-associated antigens. αv regulates TLR signalling by promoting recruitment of the autophagy component LC3 (microtubule-associated proteins 1 light chain 3) to TLR-containing endosomes, which is essential for progression from NF-κB to IRF signalling, and ultimately for traffic to lysosomes where signalling is terminated. Disruption of LC3 recruitment leads to prolonged NF-κB signalling and increased B-cell proliferation and antibody production. This work identifies a previously unrecognized role for αv and the autophagy components LC3 and atg5 in regulating TLR signalling and B-cell immunity.Howard Hughes Medical Institut