Homeostasis maintenance of encapsulated cells

Cell niche homeostasis plays a critical role in many bodily functions including tissue functionality, stem cell maintenance and differentiation, wound healing, cancer development and propagation, and many others. Many tissue engineering approaches overlook the importance of engineered constructs homeostasis, in particular for transplantation purposes. Here, we present a study of the effect of encapsulation duration on engineered tissue maturation and provide a protocol for the evaluation of critical conditions for transplantation purposes. In brief, SHSY5Y human neuroblastoma cells were encapsulated in 2% alginate by electrohydrodynamic jetting method for up to 4 weeks. We evaluated extracellular matrix niche formation and tissue maturation in situ through COL1A1 expression. In in vitro conditions, we studied the ability of cells to maintain their critical functions after being released from alginate beads. Cellular viability was evaluated via an apoptosis/necrosis detection kit and AlamarBlue assay, and functionality via immunocytochemistry. We proved the importance of engineered tissue homeostasis stabilization for future cell recovery, in particular, for our system cells encapsulated for 28 days met all critical requirements for successful tissue transplantation. Maturation of engineered tissue constructs could be accelerated by enriching alginate with growth factors or extracellular matrix molecules.     

The role of interstitial macrophages in nephropathy of type 2 diabetic db/db mice

Diabetic nephropathy is associated with interstitial macrophage infiltrates, but their contribution to disease progression is unclear. We addressed this question by blockade of chemokine receptor (CCR)1 because CCR1 mediates the macrophage recruitment to the renal interstitium. In fact, when CCR1 was blocked with BL5923, a novel orally available CCR1 antagonist, the interstitial recruitment of ex vivo labeled macrophages was markedly decreased in uninephrectomized male db/db mice with advanced diabetic nephropathy. Likewise, BL5923 (60 mg/kg, twice a day) orally administered from months 5 to 6 of life reduced the numbers of interstitial macrophages in uninephrectomized db/db mice. This was associated with reduced numbers of Ki-67 proliferating tubular epithelial and interstitial cells, tubular atrophy, and interstitial fibrosis in uninephrectomized db/db mice. Glomerular pathology and proteinuria were not affected by the CCR1 antagonist. BL5923 reduced renal mRNA expression of Ccl2, Ccr1, Ccr2, Ccr5, transforming growth factor-beta1, and collagen I-alpha1 when compared with untreated uninephrectomized male db/db mice of the same age. Thus, we identified a previously unrecognized role for interstitial macrophages for tubulointerstitial injury, loss of peritubular microvasculature, interstitial inflammation, and fibrosis in type 2 diabetic db/db mice. These data identify oral treatment with the CCR1 antagonist BL5923 as a potential therapy for late-stage diabetic nephropathy.     

Delayed chemokine receptor 1 blockade prolongs survival in collagen 4A3-deficient mice with Alport disease

Human Alport disease is caused by a lack of the alpha3-, 4-, or 5-chain of type IV collagen (COL4A). Affected humans and COL4A3-deficient mice develop glomerulosclerosis and progressive renal fibrosis in the presence of interstitial macrophages, but their contribution to disease progression is under debate. This question was addressed by treating COL4A3-deficient mice with BX471, an antagonist of chemokine receptor 1 (CCR1) that is known to block interstitial leukocyte recruitment. Treatment with BX471 from weeks 6 to 10 of life improved survival of COL4A3-deficient mice, associated with less interstitial macrophages, apoptotic tubular epithelial cells, tubular atrophy, interstitial fibrosis, and less globally sclerotic glomeruli. BX471 reduced total renal Cll5 mRNA expression by reducing the number of interstitial CCL5-positive cells in inflammatory cell infiltrates. Intravital microscopy of the cremaster muscle in male mice identified that BX471 or lack of CCR1 impaired leukocyte adhesion to activated vascular endothelium and transendothelial leukocyte migration, whereas leukocyte rolling and interstitial migration were not affected. Furthermore, in activated murine macrophages, BX471 completely blocked CCL3-induced CCL5 production. Thus, CCR1-mediated recruitment and local activation of macrophages contribute to disease progression in COL4A3-deficient mice. These data identify CCR1 as a potential therapeutic target for Alport disease or other progressive nephropathies associated with interstitial macrophage infiltrates.     

Bone quality, as measured by trabecular bone score in patients with adrenal incidentalomas with and without subclinical hypercortisolism

Patients with adrenal incidentalomas (AIs) and subclinical hypercortisolism (SH) have increased risk of fracture independent of bone mineral density (BMD) and possibly due to reduced bone quality. The trabecular bone score (TBS) has been proposed as a index of bone microarchitecture. The aim of the study was to investigate TBS in AI. In 102 AI patients, SH was diagnosed in the presence of at least two of the following: (1) urinary free cortisol >70 µg/24 h (193.1 nmol/L); (2) cortisol after 1‐mg dexamethasone suppression test (1‐mg DST) >3.0 µg/dL (82.8 nmol/L); or (3) adrenocorticotropic hormone (ACTH) <10 pg/mL (<2.2 pmol/L). In patients and in 70 matched controls, BMD was measured at lumbar spine (LS) and femur (neck [FN] and total [FT]) by dual X‐ray absorptiometry and TBS was assessed in the region of LS‐BMD; BMD and TBS data were reported as Z‐scores. In patients, vertebral deformities were assessed by radiograph. Patients with SH (n = 34) had lower LS‐BMD (?0.31 ± 1.17), FT‐BMD (?0.29 ± 0.91), and TBS (?3.18 ± 1.21) than patients without SH (n = 68, 0.31 ± 1.42, p = 0.03; 0.19 ± 0.97, p = 0.01; ?1.70 ± 1.54, p < 0.0001, respectively) and controls (0.42 ± 1.52, p = 0.02; 0.14 ± 0.76, p = 0.02; ?1.19 ± 0.99, p < 0.0001, respectively). TBS was inversely correlated with 1‐mg DST (β = ?0.26, t = ?2.79, p = 0.006) regardless of age, LS‐BMD, body mass index (BMI), and gender. The presence of fracture was associated with low TBS alone (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.85–12.42, p = 0.001) and with the cluster low TBS plus low LS‐BMD (OR, 4.37; 95% CI, 1.71–11.4, p = 0.002), after adjustment for age, BMI, and gender. Low TBS plus low LS‐BMD showed a good specificity (79%) for predicting fractures, whereas normal TBS (ie, > ?1.5) plus normal LS‐BMD high specificity (88.1%) for excluding fractures. Finally, TBS predicted the occurrence of a new fracture in 40 patients followed for 24 months (OR, 11.2; 95%CI, 1.71–71.41, p = 0.012) regardless of LS‐BMD, BMI, and age. In SH, bone quality, as measured by TBS, is altered. TBS is useful in detecting AI patients at risk of fractures. © 2012 American Society for Bone and Mineral Research.     

Oral lymphangiectasia and gastrointestinal Crohn disease

Lip edema with non-caseating granulomas or lymphangiectasia pose a clinical and pathological challenge. These findings can be attributed to cheilitis granulomatosa (CG), Melkersson-Rosenthal syndrome (MRS), or Crohn disease (CD) depending on the appropriate clinical context. Lymphangiectasis, in particular, is a common pathological finding in CD due to lymphatic obstruction by granulomas and intralymphatic granulomas. Because oral symptoms can precede gastrointestinal symptoms of CD or be seen in patients with asymptomatic gastrointestinal disease, the identification of lymphangiectasia should raise the possibility of underlying CD. We present a case of a young woman with several years of lip swelling, with notable lymphangiectasia and subtle granulomas on pathological evaluation. The patient was diagnosed with MRS at an outside institution and treated with systemic steroids, without further systemic evaluation. We believe that early recognition of lymphangiectasia and consideration of CD early in the work-up are critical for early diagnosis and appropriate management. Neither clinical nor histopathological findings should be used in isolation to diagnose GC, MRS, or CD as there is significant debate as to the etiology and overlapping findings of these conditions. We highlight the importance of lymphangiectasia in diagnosing underlying CD in the appropriate clinical context.     

Potentially Modifiable Risk Factors for Long-Term Cognitive Impairment After Critical Illness: A Systematic Review

Long-term cognitive impairment is common in survivors of critical illness. Little is known about the etiology of this serious complication. We sought to summarize current scientific knowledge about potentially modifiable risk factors during intensive care unit (ICU) treatment that may play a substantial role in the development of long-term cognitive impairment. All searches were run on October 1, 2017. The search strategy included Ovid MEDLINE, Ovid Embase, Ovid CDR, Cochrane Central Register of Controlled Trials and Database of Abstracts of Reviews of Effect, Scopus, and Web of Science, and included MeSH headings and keywords related to intensive care, critical care, and cognitive disorders. Searches were restricted to adult subjects. Inclusion required follow-up cognitive evaluation at least 2 months after ICU discharge. Studies assessing patients with cardiac arrest, traumatic brain injury, and cardiac surgery history were excluded. The search strategy resulted in 3180 studies. Of these, 28 studies (.88%) met our inclusion criteria and were analyzed. Delirium and duration of delirium were associated with long-term cognitive impairment after ICU admission in 6 of 9 studies in which this factor was analyzed. Weaker and more inconsistent associations have been reported with hypoglycemia, hyperglycemia, fluctuations in serum glucose levels, and in-hospital acute stress symptoms. Instead, most of the studies did not find significant associations between long-term cognitive impairment and mechanical ventilation; use of sedatives, vasopressors, or analgesic medications; enteral feeding; hypoxia; extracorporeal membrane oxygenation; systolic blood pressure; pulse rate; or length of ICU stay. Prolonged delirium may be a risk factor for long-term cognitive impairment after critical illness, though this association has not been entirely consistent across studies. Other potentially preventable factors have not been shown to have strong or consistent associations with long-term cognitive dysfunction in survivors of critical illness.     

Spiegelmer inhibition of CCL2/MCP-1 ameliorates lupus nephritis in MRL-(Fas)lpr mice

The monocyte chemoattractant protein CCL2 is crucial for monocyte and T cell recruitment from the vascular to the extravascular compartment at sites of inflammation. CCL2 is expressed in human lupus nephritis and was shown to mediate experimental lupus; therefore, CCL2 antagonists may be beneficial for therapy. This study describes the l-enantiomeric RNA oligonucleotide mNOX-E36, a so-called Spiegelmer that binds murine CCL2 with high affinity and neutralizes its action in vitro and in vivo. The mirror image configuration of the Spiegelmer confers nuclease resistance and thus excellent biostability. mNOX-E36 does not induce type I IFN via Toll-like receptor-7 or cytosolic RNA receptors, as recently shown for certain synthetic D-RNA. Autoimmune-prone MRL(lpr/lpr) mice that were treated with a polyethylene glycol form of mNOX-E36 from weeks 14 to 24 of age showed prolonged survival associated with a robust improvement of lupus nephritis, peribronchial inflammation, and lupus-like inflammatory skin lesions. Thus, mNOX-E36-based inhibition of CCL2 represents a novel strategy for the treatment of autoimmune tissue injury, such as lupus nephritis.