CD16+ monocytes and skewed macrophage polarization toward M2 type hallmark heart transplant acute cellular rejection

Background: During acute heart transplant rejection, infiltration of lymphocytes and monocytes is followed by endothelial injury and eventually myocardial fibrosis. To date, no information is available on monocyte-macrophage-related cellular shifts and their polarization status during rejection. Here, we aimed to define and correlate monocyte-macrophage endomyocardial tissue profiles obtained at rejection and time points prior to rejection, with corresponding serial blood samples in 25 heart transplant recipients experiencing acute cellular rejection. Additionally, 33 healthy individuals served as control. Materials and methods: Using histology, immunohistochemistry, confocal laser scan microscopy, and digital imaging expression of CD14, CD16, CD56, CD68, CD80, and CD163 were explored to define monocyte and macrophage tissue profiles during rejection. Fibrosis was investigated using Sirius Red stainings of rejection, non-rejection, and 1-year biopsies. Expression of co-stimulatory and migration-related molecules on circulating monocytes, and production potential for pro- and anti-inflammatory cytokines were studied using flow cytometry. Results: At tissue level, striking CD16+ monocyte infiltration was observed during rejection (p < 0.001). Significantly more CD68+CD163+ M2 macrophages were documented during rejection compared to barely present CD68+CD80+ M1 macrophages. Rejection was associated with severe fibrosis in 1-year biopsies (p < 0.001). Irrespective of rejection status, decreased frequencies of circulating CD16+ monocytes were found in patients compared to healthy individuals. Rejection was reflected by significantly increased CD54 and HLA-DR expression on CD16+ monocytes with retained cytokine production potential. Conclusion: CD16+ monocytes and M2 macrophages hallmark the correlates of heart transplant acute cellular rejection on tissue level and seem to be associated with fibrosis in the long term

Periostin Is Expressed by Pericytes and Is Crucial for Angiogenesis in Glioma

The expression of the matricellular protein periostin has been associated with glioma progression. In previous work we found an association of periostin with glioma angiogenesis. Here, we screen gliomas for POSTN expression and identify the cells that express periostin in human gliomas. In addition, we study the role of periostin in an in vitro model for angiogenesis. The expression of periostin was investigated by RT-PCR and by immunohistochemistry. In addition, we used double labeling and in situ RNA techniques to identify the expre

Quantification of Calcyclin and Heat Shock Protein 90 in Sera from Women with and without Preeclampsia by Mass Spectrometry

Purpose: The objective of present study is to determine serum levels and placental distribution of two interacting proteins calcyclin and heat shock protein 90 in preeclampsia. Experimental design: Maternal serum levels of calcyclin and heat shock protein 90 are compared throughout pregnancy from the first trimester till term among women with preeclampsia (n = 43) and age-matched normotensive pregnant controls (n = 46). A serum-based 2D LC-MS assay using Parallel Reaction Monitoring is applied to quantify both calcyclin and heat shock protein 90. Results: Serum levels of calcyclin are significantly lower in patients with preeclampsia in the second trimester of pregnancy as compared to controls (p < 0.05). Serum levels of heat shock protein 90 are significantly higher in patients with preeclampsia in the third trimester as compared to controls (p < 0.001). Conclusion and clinical relevance: Both interacting proteins calcyclin and heat shock protein 90 are notably changed in preeclamptic patients compared to controls. Calcyclin is already decreased before the onset of preeclampsia in the second trimester and HSP90 is strongly increased in the third trimester. This suggests that these proteins may play a role in the pathogenesis of preeclampsia and ought to be investigated in large cohort studies as molecular biomarkers

Extracellular matrix analysis of human renal arteries in both quiescent and active vascular state

In vascular tissue engineering strategies, the addition of vascular-specific extracellular matrix (ECM) components may better mimic the in vivo microenvironment and potentially enhance cell–matrix interactions and subsequent tissue growth. For this purpose, the exact composition of the human vascular ECM first needs to be fully characterized. Most research has focused on characterizing ECM components in mature vascular tissue; however, the developing fetal ECM matches the active environment required in vascular tissue engineering more closely. Consequently, we characterized the ECM protein composition of active (fetal) and quiescent (mature) renal arteries using a proteome analysis of decellularized tissue. The obtained human fetal renal artery ECM proteome dataset contains higher levels of 15 ECM proteins versus the mature renal artery ECM proteome, whereas 16 ECM proteins showed higher levels in the mature tissue compared to fetal. Elastic EC

Cryo-Gel embedding compound for renal biopsy biobanking

Optimal preservation and biobanking of renal tissue is vital for good diagnostics and subsequent research. Optimal cutting temperature (OCT) compound is a commonly used embedding medium for freezing tissue samples. However, due to interfering polymers in OCT, analysis as mass spectrometry (MS) is difficult. We investigated if the replacement of OCT with Cryo-Gel as embedding compound for rena

Brain-homing CD4+ T cells display glucocorticoid-resistant features in MS

Objective To study whether glucocorticoid (GC) resistance delineates disease-relevant T helper (Th) subsets that home to the CNS of patients with early MS. Methods The expression of key determinants of GC sensitivity, multidrug resistance protein 1 (MDR1/ ABCB1) and glucocorticoid receptor (GR/NR3C1), was investigated in proinflammatory Th subsets and compared between natalizumab-treated patients with MS and healthy individuals. Blood, CSF, and brain compartments from patients with MS were assessed for t

Human kidney organoids produce functional renin

Renin production by the kidney is of vital importance for salt, volume, and blood pressure homeostasis. The lack of human models hampers investigation into the regulation of renin and its relevance for kidney physiology. To develop such a model, we used human induced pluripotent stem cell–derived kidney organoids to study the role of renin and the renin-angiotensin system in the kidney. Extensive characterization of the kidney organoids revealed kidney-specific cell populations consisting of podocytes, proximal and distal tubular cells, stromal cells and endothelial cells. We examined the presence of various components of the renin-angiotensin system such as angiotensin II receptors, angiotensinogen, and angiotensin-converting enzymes 1 and 2. We identified by single-cell sequencing, immunohistochemistry, and functional assays that cyclic AMP stimulation induces a subset of pericytes to increase the synthesis and secretion of enzymatically active renin. Renin production by the organoids was responsive to regulation by parathyroid hormone. Subcutaneously implanted kidney organoids in immunodeficient IL2Ry-/-Rag2-/- mice were successfully vascularized, maintained tubular and glomerular structures, and retained capacity to produce renin two months after implantation. Thus, our results demonstrate that kidney organoids express renin and provide insights into the endocrine potential of human kidney organoids, which is important for regenerative medicine in the context of the endocrine system

Central role of dendritic cells in pulmonary arterial hypertension in human and mice

The pathogenesis of idiopathic pulmonary arterial hypertension (IPAH) is not fully under-stood, but evidence is accumulating tha

Chemokine receptor CCR7 expression predicts poor outcome in uveal melanoma and relates to liver metastasis whereas expression of CXCR4 is not of clinical re

Purpose. To examine the prognostic relevance of expression of the chemokine receptors CCR7 and CXCR4 and its ligand CXCL12 in uveal melanoma in nonmetastatic and metastatic patients with correlation to liver metastasis and overall survival. Methods. Primary uveal melanoma specimens from 19 patients with correlating liver metastasis specimens and 30 primary uveal melanoma specimens of patients without metastasis were collected between the years 1988 and 2008. Expression of CCR7, CXCR4, and CXCL12 were studied using immunohistochemistry. Single nucleotide polymorphism (SNP) arrays were used to examine gains or losses of chromosomes 1, 3, 6, and 8 and the regions of CCR7 (17q12-q21.2), CXCR4 (2q21), and CXCL12 (10q11.1) genes. Results. Strong cytoplasmic staining for CCR7 correlated with the presence of epithelioid cells (P = 0.037), tumor thickness (P = 0.011), lymphocytic infiltration (P = 0.041), and necrosis (P = 0.045). Nuclear staining for CXCR4 correlated with lymphocytic infiltration (P = 0.017). CXCL12 showed no correlation to histologic parameters. Single nucleotide polymorphism analyses showed no copy number variations in the regions of CCR7, CXCR4, or CXCL12. Strong expression of CCR7 was observed in 76% of the metastatic patients and 0% of nonmetastasis patients. In multivariate analysis, CCR7 staining was inversely correlated to overall survival and disease-free survival, whereas CXCR4 nuclear staining was not. Conclusions. Our data suggest that CCR7 plays a role in uveal melanoma metastasis and is associated with poor survival. CCR7 and its involved related pathways are of prognostic value in uveal melanoma and may prove to be a target for therapeutic intervention