Successful Xenografts of Second Trimester Human Fetal Brain and Retinal Tissue in the Anterior Chamber of the Eye of Adult Immunosuppressed Rats

Successful xenografting of first trimester human fetal CNS tissue and retina has been reported in the literature. We wished to test the feasibility ofusing the anterior chamber ofthe rat eye to support the development of more mature human fetal xenografts. Here we report on the successful outcome of human brain and retinal transplants. Adult host rats immunosuppressed with cyclosporin A accepted these xenografts and supported their further development. Periodic examination of the host eyes using a direct ophthalmoscope or an ophthalmic slit lamp permitted direct visual monitoring of the health and growth of the transplants. Histologically it was possible to identify neuronal, macroglial, and microglial (macrophage) cell types within the grafts. Mitotic activity and histogenetic differentiation took place. Blood vessels filled with hematic cells were commonly present within the grafts. The walls of these vessels prevented the leakageofhorseradish peroxidase, suggesting the presence of a functional brain-blood barrier in the graft. These results indicate that it is possible to use a small animal model to study normal and pathological phenomena oniate fetal human neural tissues. Our group has already taken advantage of the model to achieve HIV infectivity offetal human brain outside the human body

Chemokine transport across human vascular endothelial cells

Leukocyte migration across vascular endothelium is mediated by chemokines that are either synthesized by the endothelium or transferred across the endothelium from the tissue. The mechanism of transfer of two chemokines, CXCL10 (interferon gamma inducible protein [IP]-10) and CCL2 (macrophage chemotactic protein [MCP]-1), was compared across dermal and lung microvessel endothelium and saphenous vein endothelium. The rate of transfer depended on both the type of endothelium and the chemokine. The permeability coefficient (Pe) for CCL2 movement across saphenous vein was twice the value for dermal endothelium and four times that for lung endothelium. In contrast, the Pe value for CXCL10 was lower for saphenous vein endothelium than the other endothelia. The differences in transfer rate between endothelia was not related to variation in paracellular permeability using a paracellular tracer, inulin, and immunoelectron microscopy showed that CXCL10 was transferred from the basal membrane in a vesicular compartment, before distribution to the apical membrane. Although all three endothelia expressed high levels of the receptor for CXCL10 (CXCR3), the transfer was not readily saturable and did not appear to be receptor dependent. After 30 min, the chemokine started to be reinternalized from the apical membrane in clathrin-coated vesicles. The data suggest a model for chemokine transcytosis, with a separate pathway for clearance of the apical surface

Expression of chemokines and their receptors by human brain endothelium: Implications for multiple sclerosis

Leukocyte migration into the CNS is mediated by chemokines, expressed on the surface of brain endothelium. This study investigated the production of chemokines and expression of chemokine receptors by human brain endothelial cells (HBEC), in vitro and in situ in multiple sclerosis tissue. Four chemokines (CCL2, CCL5, CXCL8 and CXCL10), were demonstrated in endothelial cells in situ, which was reflected in the chemokine production by primary HBEC and a brain endothelial cell line, hCEMC/D3. CXCL8 and CCL2 were constitutively released and increased in response to TNF and/or IFN . CXCL10 and CCL5 were undetectable in resting cells but were secreted in response to these cytokines. TNF strongly increased the production of CCL2, CCL5 and CXCL8, while IFN up-regulated CXCL10 exclusively. CCL3 was not secreted by HBECs and appeared to be confined to astrocytes in situ. The chemokine receptors CXCR1 and CXCR3 were expressed by HBEC both in vitro and in situ, and CXCR3 was up-regulated in response to cytokine stimulation in vitro. By contrast, CXCR3 expression was reduced in silent MS lesions. Brain endothelium expresses particularly high levels of CXCL10 and CXCL8, which may account for the predominant TH1-type inflammatory reaction seen in chronic conditions such as multiple sclerosis

Loss of Caveolin-1 in Metastasis-Associated Macrophages Drives Lung Metastatic Growth through Increased Angiogenesis

Although it is well established that tumor-associated macrophages take part in each step of cancer progression, less is known about the distinct role of the so-called metastasis-associated macrophages (MAMs) at the metastatic site. Previous studies reported that Caveolin-1 (Cav1) has both tumor-promoting and tumor-suppressive functions. However, the role of Cav1 in bone-marrow-derived cells is unknown. Here, we describe Cav1 as an anti-metastatic regulator in mouse models of lung and breast cancer pulmonary metastasis. Among all the recruited inflammatory cell populations, we show that MAMs uniquely express abundant levels of Cav1. Using clodronate depletion of macrophages, we demonstrate that macrophage Cav1 signaling is critical for metastasis and not for primary tumor growth. In particular, Cav1 inhibition does not affect MAM recruitment to the metastatic site but, in turn, favors angiogenesis. We describe a mechanism by which Cav1 in MAMs specifically restrains vascular endothelial growth factor A/vascular endothelial growth factor receptor 1 (VEGF-A/VEGFR1) signaling and its downstream effectors, matrix metallopeptidase 9 (MMP9) and colony-stimulating factor 1 (CSF1).FWO-Strategic Basic Research (SB) doctoral fellowship (1S26917N), G.D.C. by a Pegasus FWO-Marie Curie fellowship (12114113N), A.I.O. by FCT Portugal (SFRH/BD/52287/2013), and M.E. by the DFG (EH 472/1-1) and Kom op tegen Kanker (Stand up to Cancer), the Flemish cancer society (2016/10538/2453). B.M.C. was funded by FCT Portugal (IF/00601/2012). M.M. received an ERC starting grant (OxyMO, 308459) and long-term structural Methusalem funding by the Flemish government (METH.14.08)info:eu-repo/semantics/publishedVersio

No Effect of One-Year Treatment with Indomethacin on Alzheimer's Disease Progression: A Randomized Controlled Trial

Contains fulltext : 71117.pdf (publisher's version ) (Open Access)BACKGROUND: The objective of this study was to determine whether treatment with the nonselective nonsteroidal anti-inflammatory drug (NSAID) indomethacin slows cognitive decline in patients with Alzheimer's disease (AD). METHODOLOGY/PRINCIPAL FINDINGS: This double-blind, randomized, placebo-controlled trial was conducted between May 2000 and September 2005 in two hospitals in the Netherlands. 51 patients with mild to moderate AD were enrolled into the study. Patients received 100 mg indomethacin or placebo daily for 12 months. Additionally, all patients received omeprazole. The primary outcome measure was the change from baseline after one year of treatment on the cognitive subscale of the AD Assessment Scale (ADAS-cog). Secondary outcome measures included the Mini-Mental State Examination, the Clinician's Interview Based Impression of Change with caregiver input, the noncognitive subscale of the ADAS, the Neuropsychiatric Inventory, and the Interview for Deterioration in Daily life in Dementia. Considerable recruitment problems of participants were encountered, leading to an underpowered study. In the placebo group, 19 out of 25 patients completed the study, and 19 out of 26 patients in the indomethacin group. The deterioration on the ADAS-cog was less in the indomethacin group (7.8+/-7.6), than in the placebo group (9.3+/-10.0). This difference (1.5 points; CI -4.5-7.5) was not statistically significant, and neither were any of the secondary outcome measures. CONCLUSIONS/SIGNIFICANCE: The results of this study are inconclusive with respect to the hypothesis that indomethacin slows the progression of AD

Chemokine receptor expression in rat adjuvant-induced arthritis

Objective Chemokine receptors mediate leukocyte migration into inflamed rheumatoid arthritis (RA) synovial tissue (ST). Knowledge of their distribution is crucial for understanding the evolution of the inflammatory process. In this study, we used rat adjuvant-induced arthritis (AIA), a model for RA, to define the temporospatial expression of chemokine receptors. Methods ST from rats with AIA was immunostained, the percentage of cells expressing each receptor was determined, and findings were correlated with levels of inflammation. Chemokine receptor expression was evaluated on rat macrophages in vitro. Results CCR1, a receptor for macrophage inflammatory protein 1Α (MIP-1Α)/CCL3 and RANTES/CCL5, exhibited high constitutive expression on macrophages in AIA. CCR5, binding MIP-1Α/CCL3 and RANTES/CCL5, was up-regulated on ST macrophages during the course of AIA, correlating with macrophage expression of CCR2, a receptor for monocyte chemoattractant protein 1/CCL2. Endothelial cell (EC) CCR2 was down-regulated as arthritis progressed, inversely correlating with inflammation. CCR3, another RANTES/CCL5 receptor, was constitutively high on macrophages in vivo and in vitro, with down-regulation during AIA. CXCR4, a receptor for stromal cell–derived factor 1/CXCL12), was prominently up-regulated on ECs, preceding the peak of inflammation. Conclusion These findings show that 1) constitutive expression of CCR1 on macrophages remains high during AIA; 2) CCR2 and CCR3 may play a role in initial recruitment of leukocytes to ST in AIA; 3) macrophage expression of CCR2 and CCR5 may be important for sustaining inflammatory changes; and 4) EC CXCR4 may be a harbinger of inflammatory changes. Our results may help guide chemokine receptor blockade–targeting treatment strategies in inflammatory arthritis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48755/1/21476_ftp.pd

The Other\u27s Other: Negotiating Normativity in Contemporary Photography from the United States

Despite all of the recent attention paid to issues of identity in art history, mainstream ideals of normativity have yet to be fully analyzed and reclaimed as subject positions from which artistic examinations begin. As a symptom of larger culture, there often remains a lack of what sociologist Ruth Frankenberg refers to as cognizance\u27 about the continuing role of normative ideals as they are assumed to be unmarked, or transcendent, positions. While all four of the case studies in this project visually challenge assumptions of normativity, the reception of the work and/or the artist\u27s own descriptions negate some of the criticality offered by their series and demonstrate this lack of cognizance in contemporary U.S. culture. Throughout my project, I offer additional interpretations of the artworks in order to mark the unmarked and to add to the growing body of scholarship that challenges normativity\u27s stronghold in contemporary culture. Case studies in this study about contemporary art photographs include: Suzanne Opton\u27s Soldier (2004-2005) and Citizen (2007), which imagine and order the (domestic) nation in relation to the foreign amid processes of Empire; Gregory Crewdson\u27s tableaux Twilight (1998-2002), Dream House (2002), and Beneath the Roses (2003-2007) that construct normativity by situating the suburbs as an ideal space that thus creates difference between the people who seem to \u27belong\u27 in the suburbs and those who do not; Nikki S. Lee\u27s The Ohio Project (1999) as it replicates dominant narrative constructions about subcultures without doing much to challenge the construction of such narratives in the first place; and Kerry Skarbakka\u27s The Struggle to Right Oneself (begun in 2002) that functions as a site to examine how a white male artist must negotiate his own position toward ideals of white masculinity.\u2

The role of endothelial chemokine receptor CCR2 in monocyte chemoattractant protein-1-mediated leukocyte migration across the blood-brain barrier

Previous results from this laboratory revealed the presence of high-affinity, saturable binding sites for monocyte chemoattractant protein-1 (MCP-1) along human brain microvessels (Andjelkovic et al., 1999; Andjelkovic and Pachter, 2000), which suggested that CCR2, the recognized receptor for this chemokine, was expressed by the brain microvascular endothelium. To directly test the role of CCR2 in mediating MCP-1 interactions with the brain microvasculature, MCP-1 binding activity was assessed in murine brain microvessels isolated from wildtype mice and CCR2(−/−) mice engineered to lack this receptor. Results demonstrate that MCP-1 binding is greatly attenuated in microvessels prepared from CCR2(−/−) mice as compared to their wildtype controls. Moreover, microvessels from wildtype mice exhibited MCP-1-induced downmodulation following MCP-1 binding, and that the recovery of this binding activity was not dependent upon de novo protein synthesis. Furthermore, it was shown that MCP-1 was internalized within wild-type microvessels, but not within microvessels obtained from CCR2(−/−) mice. This further validated that CCR2 is obligatory for MCP-1 endocytosis. The internalization of MCP-1, but not transferrin, was inhibited by the disruption of caveolae. Internalized MCP-1 also co-localized at some sites with caveolin-1, a major protein of caveolae, implying that this chemokine is endocytosed, in part, via non-clathrin-coated vesicles. These results prompt consideration that MCP-1 signals may be relayed across the blood-brain barrier by highly specialized interactions of this chemokine with its cognate receptor—CCR2—along brain microvascular endothelial cells. ^ The contribution of CCR2 to MCP-1-induced transendothelial migration was evaluated through ‘mix-and-match’ experiments where endothelial or mononuclear cells from either wildtype or CCR2(−/−) were utilized. Specifically, this study assessed if CCR2 expression by brain microvascular endothelial cells (BMEC) facilitates peritoneal macrophage (pMØ) transendothelial migration. Results were that the expression of CCR2 by pMØ is required for these cells to undergo MCP-1-stimulated transmigration. Moreover, it was also demonstrated that CCR2 expression by BMEC was found to be critical for pMØ transmigration. Furthermore, cellular components from both wildtype and CCR2(−/−) were found to support transendothelial migration in response to another chemokine, MIP-1α. These findings underscore the contribution of CCR2 in MCP-1-stimulated transmigration and highlight a novel role for chemokine receptors on endothelia.