One of the thorny problems currently impeding the applications of the fluorescence imaging technique is the poor spatial resolution in deep tissue. Ultrasound-switchable fluorescence (USF) imaging is ...a novel imaging tool that has recently been explored to possibly surmount the above-mentioned bottleneck. Herein, a β-cyclodextrin/indocyanine green (ICG) complex-encapsulated poly(N-isopropylacrylamide) (PNIPAM) nanogel was synthesized and studied for
ex vivo
/
in vivo
deep tissue/high-resolution near infrared USF (NIR-USF) imaging. To be specific, our results revealed that the average diameter of the as-prepared nanogels was significantly decreased to ~ 32 nm from ~ 335 nm compared to the reported ICG-PNIPAM nanoparticles. Additionally, the excitation/ emission characteristics of the ICG itself in present nanogels were almost completely retained, and the resultant nanogel exhibited high physiological stability and positive biocompatibility. In particular, the signal-to-noise ratio of the USF image for the PNIPAM/ β-cyclodextrin/ICG nanogel (33.01 ± 2.42 dB) was prominently higher than that of the ICG-PNIPAM nanoparticles (18.73 ± 0.33 dB) in 1.5-cm-thick chicken breast tissues. The NIR-USF imaging in 3.5-cm-thick chicken breast tissues was achieved using this new probe. The
ex vivo
NIR-USF imaging of the mouse liver was also successfully obtained. Animal experiments showed that the present nanogels were able to be effectively accumulated into U87 tumor-bearing mice via enhanced permeability and retention effects, and the high-resolution NIR-USF imaging of
in vivo
tumor was efficiently acquired. The metabolism and
in vivo
biodistribution of the nanogels were evaluated. Overall, the results suggest that the current nanogel is a highly promising NIR-USF probe for deep tissue and high-resolution USF imaging.
Toxoplasma gondii infection causes adverse pregnancy outcomes by affecting the expression of immunotolerant molecules in decidual immune cells. Galectin-9 (Gal-9) is widely expressed in decidual ...macrophages (dMphi) and is crucial for maintaining normal pregnancy by interacting with the immunomodulatory protein T-cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3). However, the effects of T. gondii infection on Gal-9 expression in dMphi, and the impact of altered Gal-9 expression levels on the maternal-fetal tolerance function of decidual natural killer (dNK) cells, are still unknown. Pregnancy outcomes of T. gondii-infected C57BL/6 and Lgals9.sup.-/- pregnant mice models were recorded. Expression of Gal-9, c-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), and Forkhead box protein O1 (FOXO1) was detected by western blotting, flow cytometry or immunofluorescence. The binding of FOXO1 to the promoter of Lgals9 was determined by chromatin immunoprecipitation-polymerase chain reaction (ChIP-PCR). The expression of extracellular signal-regulated kinase (ERK), phosphorylated ERK (p-ERK), cAMP-response element binding protein (CREB), phosphorylated CREB (p-CREB), T-box expressed in T cells (T-bet), interleukin 10 (IL-10), and interferon gamma (IFN-gamma) in dNK cells was assayed by western blotting. Toxoplasma gondii infection increased the expression of p-JNK and FOXO1 in dMphi, resulting in a reduction in Gal-9 due to the elevated binding of FOXO1 with Lgals9 promoter. Downregulation of Gal-9 enhanced the phosphorylation of ERK, inhibited the expression of p-CREB and IL-10, and promoted the expression of T-bet and IFN-gamma in dNK cells. In the mice model, knockout of Lgals9 aggravated adverse pregnancy outcomes caused by T. gondii infection during pregnancy. Toxoplasma gondii infection suppressed Gal-9 expression in dMphi by activating the JNK/FOXO1 signaling pathway, and reduction of Gal-9 contributed to dysfunction of dNK via Gal-9/Tim-3 interaction. This study provides new insights for the molecular mechanisms of the adverse pregnancy outcomes caused by T. gondii.
Toxoplasma gondii infection during pregnancy can lead to fetal defect(s) or congenital complications. The inhibitory molecule B7-H4 expressed on decidual macrophages (dMφ) plays an important role in ...maternal-fetal tolerance. However, the effect of B7-H4 on the function of dMφ during T. gondii infection remains unclear.
Changes in B7-H4 expression on dMφ after T. gondii infection were explored both in vivo and in vitro. B7-H4
pregnant mice (pregnant mice with B7-H4 gene knockout) and purified primary human dMφ treated with B7-H4 neutralizing antibody were used to explore the role of B7-H4 signaling on regulating the membrane molecules, synthesis of arginine metabolic enzymes and cytokine production by dMφ with T. gondii infection. Also, adoptive transfer of dMφ from wild-type (WT) pregnant mice or B7-H4
pregnant mice to infected B7-H4
pregnant mice was used to examine the effect of B7-H4 on adverse pregnancy outcomes induced by T. gondii infection.
The results illustrated that B7-H4
pregnant mice infected by T. gondii had poorer pregnancy outcomes than their wild-type counterparts. The expression of B7-H4 on dMφ significantly decreased after T. gondii infection, which resulted in the polarization of dMφ from the M2 toward the M1 phenotype by changing the expression of membrane molecules (CD80, CD86, CD163, CD206), synthesis of arginine metabolic enzymes (Arg-1, iNOS) and production of cytokines (IL-10, TNF-α) production. Also, we found that the B7-H4 downregulation after T. gondii infection increased iNOS and TNF-α expression mediated through the JAK2/STAT1 signaling pathway. In addition, adoptive transfer of dMφ from a WT pregnant mouse donor rather than from a B7-H4
pregnant mouse donor was able to improve adverse pregnancy outcomes induced by T. gondii infection.
The results demonstrated that the downregulation of B7-H4 induced by T. gondii infection led to the dysfunction of decidual macrophages and contributed to abnormal pregnancy outcomes. Moreover, adoptive transfer of B7-H4
dMφ could improve adverse pregnancy outcomes induced by T. gondii infection.
Primary infection of Toxoplasma gondii can cause serious abnormal pregnancy outcomes such as miscarriage and stillbirth. Inhibitory molecule B7-H4 is abundantly expressed in dendritic cells (DCs) and ...plays an important role in maintaining immune tolerance. However, the role of B7-H4 in decidual DCs (dDCs) in T. gondii-induced abnormal pregnancy outcomes is not clear.
We established T. gondii-infected abnormal pregnancy model in wild-type (WT) and B7-H4 knockout (B7-H4
) pregnant mice in vivo and cultured primary human dDCs in vitro. The abnormal pregnancy outcomes were observed and the expression of B7-H4, functional molecules (CD80, CD86, and MHC-II or HLA-DR), indoleamine 2,3-dioxygenase (IDO), cytokines (IL-10 and IL-12), and signaling molecules JAK2/STAT3 in dDCs was detected by flow cytometry and Western blot.
Our results showed that T. gondii infection significantly decreased B7-H4 expression in dDCs. In addition, B7-H4
infected pregnant mice showed much more severe abnormal pregnancy outcomes than their counterparts. Importantly, B7-H4
infection further regulated the expression of molecules (CD80, CD86, and MHC-II or HLA-DR), enzyme IDO, and cytokines (IL-10 and IL-12) in dDCs. We further discovered that B7-H4
infection impairs the JAK2/STAT3 pathway, contributing to dDC dysfunction.
Taken together, the results show that reduction of B7-H4 by T. gondii infection significantly modulates the decrease in cytokine IL-10 and enzyme IDO and the increase in cytokine IL-12, contributing to dDC dysfunction. Moreover, the JAK2/STAT3 pathway is involved in the regulation of B7-H4 by T. gondii infection and in the subsequent IDO and cytokine production, which ultimately contributes to abnormal pregnancy outcomes.
(
) is a ubiquitous intracellular protozoan parasite that causes adverse pregnancy outcomes. Its infection downregulates the Treg cell population and TGF-β level, which may contribute to adverse ...pregnancy outcomes. TGF-β plays a critical role in Treg cell development, but whether TGF-β treatment can affect the number and function of Treg cells and hence alleviate adverse pregnancy outcomes caused by
infection remains elusive. In this study,
-infected pregnant mice were treated with TGF-β or TGF-β-neutralizing antibody. The pregnancy outcomes were observed on gestational day 14. The numbers of Treg cells and pSmad3, programmed death 1 (PD-1), and Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) expression of Treg cells were analyzed by flow cytometry. Histological changes were assessed using HE staining, while IL-10 and TNF-α levels were measured using ELISA. The results indicated that TGF-β treatment improved the
-induced adverse pregnancy outcomes, with alleviation of hemorrhage, restoration of uterine spiral arteries of the placenta, and increased Treg cell numbers; meanwhile, TGF-β neutralization resulted in more serious adverse pregnancy outcomes, with serious hemorrhage, more dilated uterine spiral arteries, and decreased Treg cell numbers. pSmad3 expression in CD4
cells and CTLA-4 and PD-1 levels on Treg cells were upregulated by TGF-β treatment, but downregulated by TGF-β neutralization. The ratio of IL-10/TNF-α also increased after TGF-β treatment, but decreased after TGF-β neutralization. Our data indicate that TGF-β treatment could improve adverse pregnancy outcomes caused by
infection by upregulating Treg cell differentiation and function via the TGF-β/Smad3 signaling pathway, but not the proliferation of Treg cells.
Vertical transmission of
(
) infection during gestation can result in severe complications such as abortion, congenital malformation, fetal teratogenesis, etc. Immune inhibitory molecule Tim-3 was ...discovered to be expressed on some decidual immune cells and participates in the maintenance of maternal-fetal tolerance. Dysregulation of Tim-3 expression on decidual NK (dNK) cells was observed in several cases of pregnancy complications, whereas the role of Tim-3 on dNK cells during
infection remains unclear. In the present study,
infected Tim-3
pregnant mice, and anti-Tim-3 neutralizing antibody treated and infected human dNK cells were successfully established to explore the role of Tim-3 in dysfunction of dNK cells during abnormal pregnancy. Our results illustrated that Tim-3
pregnant mice displayed more worse pregnancy outcomes with
infection compared to infected WT pregnant mice. Also, it demonstrated that Tim-3 expression on dNK cells was significantly down-regulated following
infection. Data suggested a remarkable activation of dNK cells in Tim-3
mice and anti-Tim-3 neutralizing antibody treated and infected groups, with higher ratios of activating receptor NKG2D to inhibitory receptor NKG2A or KIR2DL4, IFN-γ/IL-10, and increased granule production compared with that of the infected group. Mechanism analysis proved that
induced Tim-3 down-regulation significantly activated the phosphatidylinositol-3-kinase (PI3K)-AKT and JAK-STAT signaling pathway, by which the GranzymeB, Perforin, IFN-γ, and IL-10 production were further up-regulated. Our research demonstrated that the decrease of Tim-3 on dNK cells caused by
infection further led to dNK cells function disorder, which finally contributed to the development of abnormal pregnancy outcomes.
Toxoplasma gondii
infection during pregnancy can result in adverse pregnancy outcomes. Previously, we have reported that these outcomes are associated with the impaired function of decidual Treg ...cells; however, the detailed mechanisms involved were unclear. It has been reported that the suppressive capacity of Treg cells is dependent on PD-1 expression. The present study explored the role of decidual PD-1
+
Treg cell function in adverse pregnancy outcomes due to
T
.
gondii
infection.
Toxoplasma gondii
–infected pregnant mice were sacrificed on gestational day 14 and their pregnancy outcomes were observed. The expression of PD-1 on decidual Treg cells and expressions of Foxp3, CTLA-4, TGF-β, and IL-10 on decidual PD-1
+
and PD-1
−
Treg cells were determined using flow cytometry. The results showed that the expression of PD-1 on decidual Treg cells was clearly higher in the
T
.
gondii
–infected mice than in the normal mice. Meanwhile, the expressions of Foxp3, CTLA-4, TGF-β, and IL-10 on decidual PD-1
+
Treg cells were higher in the infected mice than in the normal mice. The expressions were higher in decidual PD1
+
Treg cells than in PD-1
−
Treg cells in the infected mice. However, these expressions on PD-1
−
Treg cells did not significantly differ between the infected and normal mice. Nonetheless, the absolute percentages of decidual PD-1
+
Treg cells decreased significantly in the infected mice compared with those in the normal mice. These results suggest that
T
.
gondii
infection mainly influences the function of decidual PD-1
+
Treg cells, which would result in an insufficiently immunotolerant microenvironment and consequently in adverse pregnancy outcomes.
A firm's competitive advantage can come not only from internal resources but also from inter‐firm innovation networks. This paper shows that network capabilities (i.e., network visioning capability, ...network constructing capability, network operating capability and network centring capability) are special skills that enable values residing in network resources. Based on a sample of 211 Chinese hi‐tech firms and by applying structural equation modelling, network capabilities are found to have a positive relationship with innovation performance. Four antecedents of network capabilities – IT maturity, openness of culture, the management system involved and experience with network activities – are also identified in the research and empirically tested. The results of this study provide a new framework that describes how networked firms can gain a competitive advantage.
(
) infection in early pregnancy can result in miscarriage, dead fetus, and other abnormalities. The LILRB4 is a central inhibitory receptor in uterine dendritic cells (uDCs) that plays essential ...immune-regulatory roles at the maternal-fetal interface. In this study,
-infected human primary uDCs and
-infected LILRB4
pregnant mice were utilized. The immune mechanisms underlying the role of LILRB4 on uDCs were explored in the development of abnormal pregnancy outcomes following
infection
and
. Our results showed that the expression levels of LILRB4 on uDCs from normal pregnant mice were obviously higher than non-pregnant mice, and peaked in mid-gestation. The LILRB4 expression on uDC subsets, especially tolerogenic subsets, from mid-gestation was obviously down-regulated after
infection and LILRB4 decrease could further regulate the expression of functional molecules (CD80, CD86, and HLA-DR or MHC II) on uDCs, contributing to abnormal pregnancy outcomes. Our results will shed light on the molecular immune mechanisms of uDCs in abnormal pregnancy outcomes by
infection.
Vertical transmission of the intracellular parasite
(
) can lead to devastating consequences during gestation. Tim-3, a negative immune regulator, is constitutively expressed on decidual macrophages, ...but its specific role during
infection has not yet been explored. In the present study, we discovered that Tim-3 plays an important role in the abnormal pregnancy due to
infection using Tim-3
pregnant mice and anti-Tim-3 neutralizing antibody treated human decidual macrophages. The results showed that abnormal pregnancy outcomes were more prevalent in Tim-3
infected pregnant mice than in wild-type infected pregnant mice. Tim-3 expression in decidual macrophages was significantly down-regulated after
infection both
and
. Tim-3 down-regulation by
infection could strengthen M1 activation and weaken M2 tolerance by changing the M1 and M2 membrane molecule expression, arginine metabolic enzymes synthesis, and cytokine secretion profiles of decidual macrophages. Moreover, Tim-3 down-regulation by
infection led to PI3K-AKT phosphorylation inhibition, downstream transcription factor C/EBPβ expression, and SOCS1 activation, which resulted in enzymes synthesis regulation and cytokines secretion. Our study demonstrates that Tim-3 plays an indispensable role in the adverse pregnancy outcomes caused by
infection.
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