1. Introduction
Hepatic ischemia/reperfusion injury (IRI) is often encountered in various clinical situations, including liver transplantation (LTx), liver resection, and trauma/shock conditions followed by resuscitation. Hepatic IRI remains the leading cause of post-hepatectomy liver failure[
1,
2,
3] and causes more than 10% of early allograft dysfunction in LTx[
4,
5].
In the meanwhile, living-donor liver transplantation (LDLT) has also been developed and spread to the world from the first successful LDLT in 1989[
6] as a therapeutic alternative to deceased donor liver transplantation (DDLT) in the era of critical shortage of donor organs. LDLT has several inherent disadvantages compared with DDLT. For example, liver graft volume is inevitably small in adult-to-adult LDLT, i.e. small-for-size syndrome (SFSS)[
7], which increases the portal venous pressure and subsequent endothelial injury. Additionally, there has been a recent transition towards the use of smaller grafts than before to increase the future remnant volume of donor livers to maximize donor safety[
8]. Hence, the grafts from living donors may presumably be more susceptible to IRI than those from deceased donors.
Multimeric von-Willebrand factor (vWF) is a well-known central player not only in physiological hemostasis but also in pathological intravascular coagulation under diverse disease conditions. Much attention has been paid to its counteracting partner,
a disintegrin-like
and
metalloproteinase with
thrombo
spondin type-1 motifs
13 (ADAMTS13), as a key player in various coagulation disorders, including thrombotic microangiopathy (TMA)[
9,
10,
11], thrombotic thrombocytopenic purpura (TTP)[
12,
13], cerebral[
14], and myocardial infarction[
15,
16,
17]. ADAMTS13 was originally discovered in 2001, whose congenital deficiency causes TTP[
12,
18,
19]. Moreover, its acquired deficiency has been shown to induce various types of microangiopathies, such as hemolytic uremic syndrome (HUS)[
12,
18,
19], atherosclerosis[
20,
21],
etc. Under physiological conditions, ADAMTS13 cleaves highly prothrombotic unusually-large vWF multimers (UL-vWFM) into appropriate size, thereby preventing excessive platelet aggregation that may occlude microvessels. Thus, ADAMTS13 plays a pivotal role in maintaining microcirculatory blood flow without interfering with primary hemostasis.
Meanwhile, it has been shown that ADAMTS13 was predominantly produced by the liver[
13,
22,
23], especially from hepatic stellate cells (HSCs)[
24], although it can also be synthesized modestly in other tissues[
25,
26,
27]. Therefore, we assumed that TMA-like pathologies might unavoidably occur in critical liver diseases potentially through the following mechanisms- i.e. ADAMTS13 production by HSCs may be decreased by liver damage, whereas highly-reactive UL-vWFM may be over-expressed from injured sinusoidal/endothelial cells. Consequently, the resulting imbalance between UL-vWFM and ADAMTS13 may lead to excessive platelet aggregation locally and systemically. Then, impaired hepatic microcirculation further accelerates UL-vWFM upregulation and ADAMTS13 downregulation. This would, in turn, be followed by much further platelet aggregation, hyper-coagulation, leukocyte adhesion/activation, and a cytokines/chemokines storm as a “vicious cycle”. However, the role of ADAMTS13 on hepatic IRI as well as LT-induced stress remains fully understood.
In this study, we first aimed to investigate the putative roles of ADAMTS13 in hepatic IRI utilizing ADAMTS13 deficient mice, and then elucidate the therapeutic potential of ADAMTS13 supplementation against a partial LT model.
2. Materials and Methods
2.1. Animals
Male ADAMTS13 knockout (KO) mice[
28] (129/
+Ter/SvJcl-TgH NCVC) were purchased from the National Cerebral and Cardiovascular Center Research Institute (Osaka, Japan), and corresponding wild-type (WT) mice were obtained from Japan CLEA (Osaka, Japan). The data of biochemical exams of blood from WT or ADAMTS13 KO mice are provided in
Supplemental Table S1. The protein and mRNA expressions are evaluated in each genotype (
Suppl. Figure S1). Male LEW/CrlCrlj rats were purchased from Charles River Laboratories (Yokohama, Japan). All animals were maintained under specific pathogen-free conditions with a 12-hour day/night rhythm and with ad libitum access to food and water. They all received humane care according to the Guide for the Care and Use of Laboratory Animals (National Institutes of Health Publication 8th, revised, 2011). All experimental protocols were approved by the Animal Research Committee of Kyoto University (MedKyo 15210).
2.2. Mouse warm IRI
We used an established mouse model of 70% partial warm hepatic IRI as previously described[
29]. To investigate the role of ADAMTS13 in hepatic IRI, WT and ADAMTS13-deficient mice were pretreated with vehicle (phosphate-buffered saline: PBS) or recombinant ADAMTS13 (W688X, kindly provided by Kaketsuken, Kumamoto, Japan) before ischemic insult and before reperfusion (20 U/body). W688X is a C-terminal truncated protein (97 kDa molecular weight) containing the cysteine-rich/spacer domain that is functionally essential for cleaving UL-vWFMs[
30]. Then, mice were subjected to warm IRI and sacrificed to collect blood and tissue samples at 2, 6, and 24 hours after reperfusion.
2.3. Rat partial liver transplantation
To mimic small-for-size grafts in adult-to-adult living-donor partial liver transplantation (LDLT), we developed a rat model of orthotopic 20% (partial liver transplantation) pLTx using a right lobe graft, as described in Supplemental materials. After 4-hour cold storage in histidine-tryptophan-ketoglutarate (HTK, Dr. Franz Köhler Chemie, Alsbach-Hähnlein, Germany) solution at 4°C, partial liver grafts were transplanted into recipients orthotopically (
Suppl. Figure S4). To investigate the therapeutic impact of W688X in rat 20% pLTx model, the recipients were randomly assigned into the following 2 groups: A group treated with vehicle, phosphate-buffered saline (PBS) or a group treated with W688X. In the latter, W688X (200 U/body in 1.5ml PBS) was administered via the penile vein twice, just before clamping major vessels in the recipient and just before reperfusion during the recipient operation. In the vehicle group, the same volume of vehicle, 1.5ml PBS, was injected in the same manner. In the 20% pLTx model with 4-hour cold storage in HTK, the survival rate was investigated for 7 days after transplantation. After pLTx, the recipients were sacrificed to collect blood and liver tissue samples at 2, 6, and 24 hours after reperfusion.
2.4. Liver enzymes and platelet counts
Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate hydrogenase (LDH) levels were measured using standard spectrophotometric methods with an automated clinical analyzer (JCA-BM9030, JEOL Ltd., Tokyo, Japan). Platelet counts were quantified using a Becton Dickinson QBC II Plus 4452 Automatic Blood Cell Counter.
2.5. Histology
Paraffin-embedded sections (4 µm thick) of liver tissues were stained with hematoxylin and eosin. The severity of liver IRI (necrosis, sinusoidal congestion, and vacuolization) was graded according to Suzuki’s criteria on a scale in a blinded manner[
31].
2.6. Quantitative analysis of hepatic microcirculation
Hepatic microcirculation was assessed by a laser Doppler flowmetry (O2C
®, LEA Medizintechnik GmbH, Giessen, Germany)[
32,
33]. The probe was placed on the liver surface (touched but without any pressure), and at least four independent points were randomly selected and recorded. The measurement was performed at 2 mm (mouse) or 8 mm (rat) depth from the liver surface, and the average value was calculated from four independent observations per animal. Relative changes in tissue blood flow to the pre-ischemic value were calculated.
2.7. Measurement of plasma ADAMTS13 activity
We employed the FRETS-VWF73 method, as described previously[
34]. Briefly, plasma samples were diluted in reaction buffer (5mM bis-Tris, 25mM CaCl
2, and 0.05% Tween-20, pH 6.0), then 4μM FRETS-VWF73 (PEPTIDE INSTITUTE, INC., Osaka, Japan) substrate solution and 10μL protease inhibitor cocktail (P8340, Sigma-Aldrich Inc., St. Louis, MO, USA) were added. After incubation, the emitted fluorescence intensity was measured using a fluorescence spectrophotometer (Fluoroskan Ascent FL, Thermo Labsystems, Helsinki, Finland) with excitation and emission at 355 and 460 nm, respectively. Plasma from naïve WT mice or LEW/CrlCrlj rats was used as the standard.
2.8. Immunofluorescence
After deparaffinization of liver sections, the antigen retrieval was performed with citrate buffer (10 mM, pH 6.0). After blocking with Protein Block Serum-Free (X0909, DAKO, Tokyo, Japan) for 30 minutes, the sections were incubated with primary rabbit anti-mouse CD42b (bs-2347R, Boston, MA, USA) or rabbit anti-rat CD41 antibody at 1:200 dilution overnight at 4°C. Subsequently, the sections were reacted with Alexa Fluor 594-conjugated goat anti-rabbit IgG (H+L) secondary antibody (Life Technologies Japan Ltd., Tokyo, Japan). The CD42b-positive area was quantified using Image J software (NIH, USA)[
35]. Negative control slides were prepared by incubation with normal rabbit IgG (sc-2027, SantaCruz, CA, USA) instead of the primary antibody (
Supplemental Figure S3).
2.9. Real-time reverse-transcription polymerase chain reaction (RT-PCR)
Total RNA was extracted from liver tissue using an RNeasy Kit (Qiagen, Venlo, Netherlands), and complementary DNA was prepared using an Omniscript RT kit (Qiagen). Quantitative PCR was performed with StepOnePlus™ Real-Time PCR System (Applied Biosystems, Tokyo, Japan) with Fast SYBR Green Master Mix or TaqMan Master Mix. Amplification conditions were as follows: 95°C for 20 seconds (sec), 95°C for 3 sec, followed by 45 cycles of 95°C for 15 sec and 60°C for 30 sec. Primers used to amplify specific gene fragments are listed in
Supplementary Table S2 [
28,
29]. Target gene expressions were calculated relative to the housekeeping gene, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), or β-actin.
2.10. Immunohistochemistry
Paraffin sections were pretreated with 3% H2O2 in methanol for 10 minutes, and then subjected to antigen retrieval in citrate buffer (10mM, pH 6.0) by microwave. After blocking with 10% rabbit serum for 20 min, the sections were incubated with primary rat anti-mouse CD68 (FA-11; AbD Serotec, Kidlington, UK) or Ly-6G (RB6-8C5; Tonbo Biosciences, Irvine, CA, USA) antibodies at 1:100 dilution or anti-vWF antibody (ab6994, Abcam, Cambridge, UK) overnight at 4°C. Subsequently, the sections were reacted with biotinylated rabbit anti-rat IgG. The sections were then incubated with VECTASTAIN Elite ABC Kit (Vector Laboratories, Burlingame, CA, USA), stained with a Liquid DAB Substrate Chromogen System (DAKO), and then observed with a BZ-9000 fluorescence microscope (Keyence, Osaka, Japan).
2.11. Apoptosis assay
Terminal deoxynucleotidyl transferase-mediated dNTP nick-end labeling (TUNEL) assays were performed for the detection of apoptosis in 4-µm-thick paraffin sections with an In Situ Apoptosis Detection Kit (Takara Bio, Shiga, Japan) according to the manufacturer’s protocol. The negative control was prepared by omitting terminal deoxynucleotidyl transferase. TUNEL-positive cells were counted in at least five high-powered fields/sections under a light microscope.
2.12. Statistical analysis
All data are expressed as means ± standard errors of the means (SEMs). Differences among the experimental groups were analyzed with a two-way analysis of variance (ANOVA) followed by Bonferroni’s post-hoc tests for time-dependent parameters or with Student’s t-tests for unpaired data sets. Survival rates were estimated with the Kaplan-Meier method and a Mantel-Cox log-rank analysis. All statistical calculations were performed using Prism 5 (GraphPad Software Inc., La Jolla, CA, USA). Differences with P values < 0.05 were considered statistically significant.
4. Discussion
In the present study, we demonstrated that hepatic IRI-induced TMA-like pathology is characterized by a significant reduction of ADAMTS13 activity and simultaneous up-regulation of vWF both in mouse warm IRI model and rat pLT model. The imbalance between prothrombotic vWF and its counter-acting partner, ADAMTS13, reached up to 5-fold higher for mRNA expression at 24 hours after reperfusion, compared with the physiological, pre-ischemic level in mouse hepatic IRI model. Consequently, plasma ADAMTS13 activity was rapidly decreased just after the onset of hepatic IR, which persisted for at least 24 hours without any recovery (
Figure 1A). In contrast, vWF upregulation in SECs started from the ischemic phase, with a burst observed by 24 hours after reperfusion, representing further enhancement of SECs damage upon reperfusion (
Figure 1B). These results indicate the high vulnerability of HSCs and SECs to hepatic IRI, both of which are main components of the sinusoidal wall, thus resulting in severe microangiopathy therein. Importantly, ADAMTS13 is exclusively produced by HSCs[
22,
24], and the liver contains an extremely large vascular bed, which, once injured, potentially expresses and releases vast amounts of UL-vWFM[
36,
37]. Thus, critical liver damage, including hepatic IRI, inevitably increases the vWF/ADAMTS13 ratio to varying degrees, thereby resulting in TMA-like pathology. Because these features appear to be unique to the liver, we would like to propose a new concept of liver damage-induced TMA-like pathology in critical liver diseases, i.e., “hepatic TMA”.
To elucidate the putative role of ADAMTS13 and the therapeutic impact of rADAMTS13 on critical liver damage, we first employed a combination of ADAMTS13-deficient mice and rADAMTS13 in a standardized model of acute liver damage, 70% partial hepatic IRI. As expected, ADAMTS13-deficiency provoked massive platelet aggregation within hepatic microvasculatures after IRI, resulting in microcirculatory impairment and subsequent parenchymal injuries, whereas rADAMTS13 administration significantly attenuated all these liver damages (
Figure 2 and
Figure 3). Based on these results, the following deteriorating process seems to be involved in hepatic IRI: First, IRI results in significant up-regulation of UL-vWFM from SECs and simultaneous down-regulation of ADAMTS13 from HSCs; massive platelet aggregation then occurs locally and systemically, eliciting microcirculatory disturbance and parenchymal inflammation, thereby falling into apoptosis/necrosis in hepatic parenchyma. The latter parts of this cascade further exacerbate the imbalance of vWF-multimers/ADAMTS13. Consequently, such a “vicious cascade” is enormously amplified, finally resulting in irreversible tissue damage, unless appropriately treated. From this perspective, rADAMTS13 supplementation could successfully eliminate such a “vicious cascade” in TMA-like pathology, thereby significantly mitigating hepatic IRI.
In addition to the aforementioned protective benefits based on the improvement of hepatic microangiopathies, significant attenuation of the inflammatory response in injured hepatic tissue was also observed. ADAMTS13 administration suppressed the infiltration of macrophages and neutrophils into the livers (
Figure 4), and pro-inflammatory cytokines and chemokines were all significantly suppressed by rADAMTS13 (
Figure 5). These results demonstrated a significant potential of ADAMTS13 to alleviate hepatic inflammation. Indeed, it may be difficult to deny that these anti-inflammatory responses mostly resulted from the amelioration of reperfusion injury itself. However, these anti-inflammatory effects were more pronounced than expected from other parameters, such as lowered transaminase release or improved microcirculation. Although there has been little evidence, De Meyer et al. also suggested the anti-inflammatory potential of ADAMTS13 in a mouse model of heart transplant[
15]. Taken together, our data suggest that ADAMTS13 per se possesses powerful anti-inflammatory potential on hepatic IRI.
Although adult-to-adult LDLT has emerged as a life-saving option for end-stage liver diseases in the era of critical donor shortage, this procedure incorporates an unavoidable disadvantage of insufficient volume of liver allografts. The possible causative factors of TMA-like disorders have been reported after LTx recipients in clinical situations [
38,
39,
40]. Hori et al. reported seven cases of TMA-like disorder after living-donor liver transplantation[
41]. The vWF/ADAMTS13 ratio in these patients increased up to 11.0 ± 2.4 (range, 7.8–14.6), coupled with extremely high peri-operative mortality of up to 71.4% (loss of five out of seven patients), despite various intensive treatments, including repeated plasma exchange. Additionally, the vWF/ADAMTS13 ratio is a significant predictor determining the severity of TMA[
42,
43,
44,
45]. However, to date, the only effective treatment for this lethal condition is plasma exchange[
46,
47,
48,
49] (and conversion of suspected drugs in some cases[
50,
51]). Thus, the high mortality rates in patients with hepatic TMA represent an “unmet medical need” in this field. Hence, we adopted the rat 20% pLTx (CIT 4 hours) model to elucidate the specific pathophysiological mechanism of TMA-like disorder after LDLT. Similar to the mouse experimental results, ADAMTS13 activity decreased less than 30% at 2, 6, and 24 hours after reperfusion (
Suppl. Figure S5), and massive expression of vWF in sinusoidal space was observed at 2, 6, and 24 hours after reperfusion in vehicle pLT group. Consequently, the imbalance between UL-vWF and ADAMTS13 activity causes the massive platelet aggregation and forms a large amount of platelet thrombi. as evident byCD41 immunofluorescence of the partial liver allograft showing that massive platelet aggregation in sinusoidal space especially at 6 and 24 hours after reperfusion. The rADAMTS13 supplementation improved the imbalance between vWF and ADAMTS13 and suppressed the massive platelet aggregation in the partial liver allograft. As a result, hepatic microcirculation was dramatically improved from 20 minutes to 24 hours after reperfusion (
Figure 6). Consequently, as shown in
Figure 7, the liver damage was ameliorated in the aspect of biochemical and histopathological examinations. Importantly, ADAMTS13 treatment improved rat 20% pLTx model’s 7-day survival rate from 40% to 80%, indicating the critical role of ADAMTS13 in pLT-induced TMA-like pathology.
In the treatment of diverse coagulation disorders including TMA, disseminated intravascular coagulation (DIC), or various organ infarctions/embolizations, developing new therapeutic intervention is generally accompanied by bleeding complications as potentially adverse effects, thus hindering its translation into clinical practice[
52,
53,
54]. In this regard, rADAMTS13 has an advantage compared with other agents in this field; no bleeding tendency. Consistent with a recent report[
15], any mice or rats treated with rADAMTS13 did not suffer from bleeding complications during and after surgery, although plasma ADAMTS13 activity was relatively higher in W688X treated groups; 1000% in mice 2 hours after surgery, 200% in rats from 2 hours to 24 hours after reperfusion (
Suppl. Figures S2 and S5). These results may imply the valuable safety of ADAMTS13 supplementation as a new therapeutic strategy in the treatment of TMA, IRI, and critical liver conditions. This unique and unobtainable feature of rADAMTS13 may facilitate its clinical translation.
In conclusion, severe liver damages inevitably deteriorate the balance between prothrombotic vWF-multimers and its cleaving protease, ADAMTS13, thereby causing microcirculatory impairment locally and systemically by forming platelets thrombi. This, in turn, results in long-lasting IRI of the liver, further enhancing the imbalance of vWF/ADAMTS13. We designate this liver damage-initiated TMA-like pathology as “hepatic TMA”. Administration of rADAMTS13 could disrupt the pathological cascades therein, thus improving severe conditions of “hepatic TMA”. Given its strong anti-inflammatory potential and valuable safety, rADAMTS13 supplementation may be a novel therapeutic intervention against critical liver diseases.
Figure 1.
Plasma ADAMTS13 activity during IRI, and imbalance between ADAMTS13 and vWF expressions induced by hepatic IRI in WT mice. (A) Time-dependent alteration of plasma ADAMTS13 activity in wild type (WT) mice after 70% partial hepatic IRI (n = 6 at each time point). (B) Chronological alterations of ADAMTS13 and vWF mRNA expressions in liver tissues during hepatic IRI (blue solid line: ADAMTS13 with vehicle, red solid line: vWF with vehicle, blue dotted line: ADAMTS13 with rADAMTS13, red dotted line: vWF with rADAMTS13). Data are represented as means ± SEM. mRNA expression of vWF: 2.21 ± 0.35 in WT + vehicle vs. 1.08 ± 0.07 in WT + rADAMTS13 at the end of ischemia, †p<0.01; 4.45 ± 0.76 in WT + vehicle vs. 1.23 ± 0.11 in WT + rADAMTS13 at 24 hours, §p<0.001. 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 6 / group).
Figure 1.
Plasma ADAMTS13 activity during IRI, and imbalance between ADAMTS13 and vWF expressions induced by hepatic IRI in WT mice. (A) Time-dependent alteration of plasma ADAMTS13 activity in wild type (WT) mice after 70% partial hepatic IRI (n = 6 at each time point). (B) Chronological alterations of ADAMTS13 and vWF mRNA expressions in liver tissues during hepatic IRI (blue solid line: ADAMTS13 with vehicle, red solid line: vWF with vehicle, blue dotted line: ADAMTS13 with rADAMTS13, red dotted line: vWF with rADAMTS13). Data are represented as means ± SEM. mRNA expression of vWF: 2.21 ± 0.35 in WT + vehicle vs. 1.08 ± 0.07 in WT + rADAMTS13 at the end of ischemia, †p<0.01; 4.45 ± 0.76 in WT + vehicle vs. 1.23 ± 0.11 in WT + rADAMTS13 at 24 hours, §p<0.001. 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 6 / group).
Figure 2.
Platelet aggregation within hepatic microvasculature and subsequent alteration of hepatic microcirculation after IRI. (A) Representative tissue sections of the ischemic liver lobes stained by immunofluorescence for CD42b (original magnification × 100). A scale bar in the right lower panel represents 100 µm. (B) CD-42b positive area quantified by Image J software. Data are represented as mean ± SEM. *p <0.05, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 4 / group). (C) Peripheral platelet counts during hepatic IRI. Data are represented as means ± SEM. *p<0.05, §p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 8 / group) (D) Hepatic microcirculation before and after reperfusion assessed by a laser Doppler flowmetry. Data are provided in the relative change to pre-ischemic value (%-decrease, Mean ± SEM). *p<0.05, †p<0.01, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 8 / group).
Figure 2.
Platelet aggregation within hepatic microvasculature and subsequent alteration of hepatic microcirculation after IRI. (A) Representative tissue sections of the ischemic liver lobes stained by immunofluorescence for CD42b (original magnification × 100). A scale bar in the right lower panel represents 100 µm. (B) CD-42b positive area quantified by Image J software. Data are represented as mean ± SEM. *p <0.05, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 4 / group). (C) Peripheral platelet counts during hepatic IRI. Data are represented as means ± SEM. *p<0.05, §p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 8 / group) (D) Hepatic microcirculation before and after reperfusion assessed by a laser Doppler flowmetry. Data are provided in the relative change to pre-ischemic value (%-decrease, Mean ± SEM). *p<0.05, †p<0.01, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 8 / group).
Figure 3.
ADAMTS13-null mutation exacerbates hepatocellular damage, while ADAMTS13 supplementation attenuates IR-induced injury. Serum AST (A), ALT (B), and LDH (C) release after IRI. (D) Representative H&E staining IR-stressed livers. Original magnification, x100. A scale bar in the right lower panel represents 100 µm. (E) Suzuki’s histological grading of liver IRI. (F) Representative TUNEL images. A scale bar in the right lower panel indicates 50 µm. Data are represented as mean ± SEM. *p<0.05, †p<0.01, §p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 8 / group).
Figure 3.
ADAMTS13-null mutation exacerbates hepatocellular damage, while ADAMTS13 supplementation attenuates IR-induced injury. Serum AST (A), ALT (B), and LDH (C) release after IRI. (D) Representative H&E staining IR-stressed livers. Original magnification, x100. A scale bar in the right lower panel represents 100 µm. (E) Suzuki’s histological grading of liver IRI. (F) Representative TUNEL images. A scale bar in the right lower panel indicates 50 µm. Data are represented as mean ± SEM. *p<0.05, †p<0.01, §p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 8 / group).
Figure 4.
Assessment of the infiltration of macrophage and neutrophil into the livers. (A) Representative liver sections stained by CD68 (A) and Ly6G (B) (original magnification × 400). A scale bar in the right lower panel represents 50 µm. Data were provided as mean and SEM. *p<0.05, **p<0.01, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 5 / group).
Figure 4.
Assessment of the infiltration of macrophage and neutrophil into the livers. (A) Representative liver sections stained by CD68 (A) and Ly6G (B) (original magnification × 400). A scale bar in the right lower panel represents 50 µm. Data were provided as mean and SEM. *p<0.05, **p<0.01, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n= 5 / group).
Figure 5.
Anti-inflammatory effect of ADAMTS13 quantified by the RT-PCR detection of gene expression of pro-inflammatory cytokines and chemokines in IRI liver. The induction ratios of cytokines (A-D) and chemokines (E, F). Data were normalized to GAPDH gene expression. Data were provided as mean and SEM. *p<0.05, **p<0.01, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 8 / group).
Figure 5.
Anti-inflammatory effect of ADAMTS13 quantified by the RT-PCR detection of gene expression of pro-inflammatory cytokines and chemokines in IRI liver. The induction ratios of cytokines (A-D) and chemokines (E, F). Data were normalized to GAPDH gene expression. Data were provided as mean and SEM. *p<0.05, **p<0.01, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 8 / group).
Figure 6.
ADAMTS13 supplementation down-regulates LT stress-induced vWF expressions and platelet aggregation. (A) Representative liver sections stained by vWF (original magnification x200). A scale bar in each panel represents 100μm. (B) representative immunofluorescence for CD41 (original magnification x100). A scale bar in each panel represents 100μm. Perioperative platelet count (C), LDH release (D), and microcirculation after partial LT. Data were provided as mean and SEM. *p<0.05, **p<0.01, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 7 / group).
Figure 6.
ADAMTS13 supplementation down-regulates LT stress-induced vWF expressions and platelet aggregation. (A) Representative liver sections stained by vWF (original magnification x200). A scale bar in each panel represents 100μm. (B) representative immunofluorescence for CD41 (original magnification x100). A scale bar in each panel represents 100μm. Perioperative platelet count (C), LDH release (D), and microcirculation after partial LT. Data were provided as mean and SEM. *p<0.05, **p<0.01, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 7 / group).
Figure 7.
ADAMTS13 treatment ameliorates LT-related hepatocellular damage and graft survival. (A) representative H&E staining (original magnification x200). (B) Quantification of Suzuki’s histological scores. Data were provided as mean and SEM. ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 8 / group). (C) Tissue damage measured by serum AST and ALT. (D) Survival rates using the log-rank test (n = 10 / group).
Figure 7.
ADAMTS13 treatment ameliorates LT-related hepatocellular damage and graft survival. (A) representative H&E staining (original magnification x200). (B) Quantification of Suzuki’s histological scores. Data were provided as mean and SEM. ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 8 / group). (C) Tissue damage measured by serum AST and ALT. (D) Survival rates using the log-rank test (n = 10 / group).
Figure 8.
Inflammatory cytokines and endothelin-1. The induction ratios of cytokines (TNF-α, IL-1β, IL-6 and endothelin-1. Data were normalized to β-actin expression. Data were shown as mean and SEM. *p<0.05, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 7 / group).
Figure 8.
Inflammatory cytokines and endothelin-1. The induction ratios of cytokines (TNF-α, IL-1β, IL-6 and endothelin-1. Data were normalized to β-actin expression. Data were shown as mean and SEM. *p<0.05, ***p<0.001, 2-way ANOVA followed by Bonferroni’s post-hoc tests (n = 7 / group).