The goal of our study was to raise monoclonal antibodies (mAbs) against endothelial cell-surface proteins specific for tumor vasculature. Here, we describe the generation and intensive characterization of mAb AA98, including its functional properties and its antigen identification. In our study, an enhanced mAb AA98 immunoreactivity was observed on stimulated human umbilical vein endothelial cells (HUVECs). In addition, mAb AA98 showed remarkably restricted immunoreactivity against intratumoral neovasculature compared with blood vessels of normal tissues. We identified the AA98 antigen as human CD146, an adhesion molecule belonging to the immunoglobulin superfamily. Data from in vitro experiments imply structural and signaling functions for endothelial CD146; however, the role of CD146 in vivo is largely unknown. Here, we show that mAb AA98 displays antiangiogenic properties in vitro and in vivo. Proliferation and migration of HUVECs were inhibited by mAb AA98 as was angiogenesis in chicken chorioallantoic membrane (CAM) assays and tumor growth in 3 xenografted human tumor models in mice. Our data provide new insights into the function of CD146 on endothelial cells, validate CD146 as a novel target for antiangiogenic agents, and demonstrate that mAb AA98 has potential as a diagnostic and therapeutic agent in vascular and cancer biology. (Blood. 2003;102:184-191)
Current influenza vaccines only confer protection against homologous viruses. We synthesized pulmonary surfactant (PS)–biomimetic liposomes encapsulating 2′,3′-cyclic guanosine monophosphate–adenosine monophosphate (cGAMP), an agonist of the interferon gene inducer STING (stimulator of interferon genes). The adjuvant (PS-GAMP) vigorously augmented influenza vaccine–induced humoral and CD8+ T cell immune responses in mice by simulating the early phase of viral infection without concomitant excess inflammation. Two days after intranasal immunization with PS-GAMP–adjuvanted H1N1 vaccine, strong cross-protection was elicited against distant H1N1 and heterosubtypic H3N2, H5N1, and H7N9 viruses for at least 6 months while maintaining lung-resident memory CD8+ T cells. Adjuvanticity was then validated in ferrets. When alveolar epithelial cells (AECs) lacked Sting or gap junctions were blocked, PS-GAMP–mediated adjuvanticity was substantially abrogated in vivo. Thus, AECs play a pivotal role in configuring heterosubtypic immunity.
Constructing
multicolor photoluminescence materials that allow
for the integration of suitable external stimuli in order to control
luminescence color conversions is a challenging objective. Multicolor
luminescent output that is regulated in an in situ photo-controlled
manner is not a common phenomenon. Herein, a photoluminescent supramolecular
assembly, prepared in two stages, is described that displays in situ
photo-tuning broad-spectrum output. Benefiting from the reversible
photo-switched constitutional interconversion of diarylethenes,
the fluorescence of a guest molecule, styrylpyridinium-modified
diarylethene, can be switched on/off by alternating ultraviolet
and visible light irradiation. Upon complexation of this guest with
a host, cucurbit[8]uril, the fluorescence intensity of the resulting
binary supramolecular nanofiber shows a drastic enhancement
when compared with that of the free guest, which can also be quenched
and recovered reversibly by light irradiation. Significantly, such
cationic supramolecular nanofibers also interact with anionic
carbon dots to form broad-spectrum output ternary supramolecular
assemblies, the fluorescence of which can be changed efficiently from
yellow to blue in an in situ photo-controlled manner. Pure white light
emission can be realized expediently in the luminescence color-conversion
process. The use of light as an external stimulus to regulate fluorescent
color conversion provides us with an opportunity to design and construct
more advanced anti-counterfeiting materials as well as visual display
instruments.
A potent adjuvant without incurring any significant skin reactogenicity is urgently needed for cutaneous vaccination. Here, we report that a natural agonist of STING, 2’3’- cyclic GMP-AMP (cGAMP) robustly augmented and prolonged cellular and humoral immune responses provoked by H5N1 and 2009 H1N1 pandemic influenza vaccines after a single dose of intradermal, but not intramuscular, immunization. The potency of cGAMP for cutaneous vaccination was ascribed to a large number of antigen presenting cells resident in the skin ready for immediate activation by cGAMP injected. On the contrary, its potency was severely compromised in the muscle because antigen presenting cells could not be promptly recruited to the injection site before injected cGAMP was diffused out. The superior adjuvant effect and safety of holds great promise to be an ideal adjuvant for cutaneous vaccination.
Thrombocytopenia is a common hematologic disorder that is managed primarily by platelet transfusions. We report here that noninvasive whole-body illumination with a special near-infrared laser cures acute thrombocytopenia triggered by g-irradiation within 2 weeks in mice, as opposed to a 5-week recovery time required in controls. The low-level laser (LLL) also greatly accelerated platelet regeneration in the presence of anti-CD41 antibody that binds and depletes platelets, and prevented a severe drop in platelet count caused by a common chemotherapeutic drug. Mechanistically, LLL stimulated mitochondrial biogenesis specifically in megakaryocytes owing to polyploidy of the cells. LLL also protected megakaryocytes from mitochondrial injury and apoptosis under stress. The multifaceted effects of LLL on mitochondria bolstered megakaryocyte maturation; facilitated elongation, branching, and formation of proplatelets; and doubled the number of platelets generated from individual megakaryocytes in mice. LLL-mediated platelet biogenesis depended on megakaryopoiesis and was inversely correlated with platelet counts, which kept platelet biogenesis in check and effectively averted thrombosis even after repeated uses, in sharp contrast to all current agents that stimulate the differentiation of megakaryocyte progenitors from hematopoietic stem cells independently of platelet counts. This safe, drug-free, donorindependent modality represents a paradigm shift in the prophylaxis and treatment of thrombocytopenia.
OBJECTIVEMitochondrial reactive oxygen species (ROS) plays a key role in diabetic retinopathy (DR) pathogenesis. However, whether simvastatin decreases diabetes-induced mitochondrial ROS production remains uncertain. The aim of this study was to clarify the beneficial effects and mechanism of action of simvastatin against diabetes-induced retinal vascular damage.RESEARCH DESIGN AND METHODSDiabetic rats and control animals were randomly assigned to receive simvastatin or vehicle for 24 weeks, and bovine retinal capillary endothelial cells (BRECs) were incubated with normal or high glucose with or without simvastatin. Vascular endothelial growth factor (VEGF) and peroxisome proliferator–activated receptor γ coactivator 1α (PGC-1α) in the rat retinas or BRECs were examined by Western blotting and real-time RT-PCR, and poly (ADP-ribose) polymerase (PARP), and p38 MAPK were examined by Western blotting. Mitochondrial membrane potential (Δψm) and ROS production were assayed using the potentiometric dye 5,5′,6,6′- Tetrachloro1,1′,3,3′-tetraethyl-benzimidazolylcarbocyanine iodide (JC-1) or CM-H2DCFDA fluorescent probes.RESULTSSimvastatin significantly upregulated PGC-1α (P < 0.01), subsequently decreased Δψm (P < 0.05) and ROS generation (P < 0.01), inhibited PARP activation (P < 0.01), and further reduced VEGF expression (P < 0.01) and p38 MAPK activity (P < 0.01). Those changes were associated with the decrease of retinal vascular permeability, retinal capillary cells apoptosis, and formation of acellular capillaries.CONCLUSIONSSimvastatin decreases diabetes-induced mitochondrial ROS production and exerts protective effects against early retinal vascular damage in diabetic rats in association with the inhibition of mitochondrial ROS/PARP pathway mediated by PGC-1α. The understanding of the mechanisms of action of statins has important implications in the prevention and treatment of mitochondrial oxidative stress-related illness such as DR.
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