A pathological joint-liver axis mediated by matrikine-activated CD4+ T cells.

The knee joint has long been considered a closed system. The pathological effects of joint diseases on distant organs have not been investigated. Herein, our clinical data showed that post-traumatic joint damage, combined with joint bleeding (hemarthrosis), exhibits a worse liver function compared with healthy control. With mouse model, hemarthrosis induces both cartilage degeneration and remote liver damage. Next, we found that hemarthrosis induces the upregulation in ratio and differentiation towards Th17 cells of CD4+ T cells in peripheral blood and spleen. Deletion of CD4+ T cells reverses hemarthrosis-induced liver damage. Degeneration of cartilage matrix induced by hemarthrosis upregulates serological type II collagen (COL II), which activates CD4+ T cells. Systemic application of a COL II antibody blocks the activation. Furthermore, bulk RNAseq and single-cell qPCR analysis revealed that the cartilage Akt pathway is inhibited by blood treatment. Intra-articular application of Akt activator blocks the cartilage degeneration and thus protects against the liver impairment in mouse and pig models. Taken together, our study revealed a pathological joint-liver axis mediated by matrikine-activated CD4+ T cells, which refreshes the organ-crosstalk axis and provides a new treatment target for hemarthrosis-related disease. Intra-articular bleeding induces cartilage degradation through down-reulation of cartilage Akt pathway. During this process, the soluble COL II released from the damaged cartilage can activate peripheral CD4+ T cells, differention into Th17 cells and secretion of IL-17, which consequently induces liver impairment. Intra-articular application of sc79 (inhibitor of Akt pathway) can prevent the cartilage damage as well as its peripheral influences.

[Study on the Therapeutic Effect of Lenalidomide on Hemophilic Arthropathy].

OBJECTIVE: To explore the effect of lenalidomide on human fibroblast-like synovial cells (HFLS) and the therapeutic efficacy on hemophilic arthropathy in hemophilia A mice model. METHODS: In vitro, to remodel the inflammatory environment of synovial tissue after hemorrhage, ferric citrate and recombinant TNF-α were added into the cell culture medium of HFLS. Cell Counting Kit-8 (CCK-8), Enzyme-linked immunosorbent assay (ELISA), Quantitative Real-time PCR (RT-qPCR) and flow cytometry were employed for detection of the effects of lenalidomide on the proliferation ability, pro-inflammatory cytokines release and apoptosis of HFLS cells. In vivo, hemophilia arthropathy was remodeled in hemophilia A mice by induction of hemarthrosis. A series of doses of lenalidomide (0.1, 0.3 and 1.0 g/kg) was administrated intra-articularly. Tissues of knee joints were collected on the 14th day after administration, and the protective effect of lenalidomide on arthritis in hemophilia A mice were evaluated by RT-qPCR and histological grading. RESULTS: In vitro, compared with the untreated control group, lenalidomide could significantly inhibit the proliferation of HFLS cells (P<0.05), and the effect was the most significant when the concentration was 0.01 µmol/L (P<0.001). Compared with the control group, lenalidomide could significantly inhibit the expression levels of TNF-α, IL-1ß, IL-6 and IFN-γ in HFLS cells (P<0.05). The flow cytometry results showed that lenalidomide could enhance the apoptotis of HFLS cells (P<0.05). The results of RT-qPCR showed that lenalidomide could significantly reduce the mRNA expression levels of TNF-α, IL-1ß, IL-6,MCP-1 and VEGF in the joint tissues (P<0.05). Histological results showed that compared with the injured group, lenalidomide could significantly reduce the pathological sequela after hemarthrosis induction, e.g. synovial thickening and neo-angiogenesis in the synovium. The protection displayed a dose-response pattern roughly. CONCLUSION: In vitro, lenalidomide can inhibit the proliferation of HFLS cells, promote their apoptosis, and inhibit the expression of pro-inflammatory cytokines. In vivo, lenalidomide can significantly decrease the expression of pro-inflammatory cytokines in the joints of mice, and prevent the development of inflammation and neo-angiogenesis. The results provide a theoretical and experimental basis for the clinical application of lenalidomide in the treatment of hemophilic arthropathy.

Selective inhibition of activated protein C anticoagulant activity protects against hemophilic arthropathy in mice.

Recurrent spontaneous or trauma-related bleeding into joints in hemophilia leads to hemophilic arthropathy (HA), a debilitating joint disease. Treatment of HA consists of preventing joint bleeding by clotting factor replacement, and in extreme cases, orthopedic surgery. We recently showed that administration of endothelial cell protein C receptor (EPCR) blocking monoclonal antibodies (mAb) markedly reduced the severity of HA in factor VIII (FVIII)-/- mice. EPCR blocking inhibits activated protein C (APC) generation and EPCR-dependent APC signaling. The present study was aimed to define the role of inhibition of APC anticoagulant activity, APC signaling, or both in suppressing HA. FVIII-/- mice were treated with a single dose of isotype control mAb, MPC1609 mAb, that inhibits anticoagulant, and signaling properties of APC, or MAPC1591 mAb that only blocks the anticoagulant activity of APC. Joint bleeding was induced by needle puncture injury. HA was evaluated by monitoring joint bleeding, change in joint diameter, and histopathological analysis of joint tissue sections for synovial hypertrophy, macrophage infiltration, neoangiogenesis, cartilage degeneration, and chondrocyte apoptosis. No significant differences were observed between MPC1609 and MAPC1591 in inhibiting APC anticoagulant activity in vitro and equally effective in correcting acute bleeding induced by the saphenous vein incision in FVIII-/- mice. Administration of MAPC1591, and not MPC1609, markedly reduced the severity of HA. MAPC1591 inhibited joint bleed-induced inflammatory cytokine interleukin-6 expression and vascular leakage in joints, whereas MPC1609 had no significant effect. Our data show that an mAb that selectively inhibits APC's anticoagulant activity without compromising its cytoprotective signaling offers a therapeutic potential alternative to treat HA.

Pathological mechanism of joint destruction in haemophilic arthropathy.

Haemophilic arthropathy (HA), caused by intra-articular haemorrhage, is one of the most common complications in patients with haemophilia. Factor replacement therapy provides missing coagulation factors to prevent children with haemophilia from joint bleeding and decreases their risk for HA. However, haemophilia patients in developing countries are still suffering from HA due to insufficient replacement therapy. Symptoms such as pain and activity limitations caused by HA seriously affect the functional abilities and quality of life of patients with HA, causing a high disability rate in the haemophilia cohort. The pathological mechanism of HA is complicated because the whole pathological mainly involves hypertrophic synovitis, osteopenia, cartilage and bone destruction, and these pathological changes occur in parallel and interact with each other. Inflammation plays an important role in the whole complex pathological process, and iron, cytokines, growth factors and other factors are involved. This review summarizes the pathological mechanism of HA to provide background for clinical and basic research.

Unique inflammatory signature in haemophilic arthropathy: miRNA changes due to interaction between blood and fibroblast-like synoviocytes.

In haemophilia, the recurrence of hemarthrosis leads to irreversible arthropathy termed haemophilic arthropathy (HA). However, HA is a unique form of arthropathy in which resident cells, such as fibroblast-like synoviocytes (FLS), come into direct contact with blood. Therefore, we hypothesized that FLS in HA could have a unique inflammatory signature as a consequence of their contact with blood. We demonstrated with ELISA and ELISPOT analyses that HA-FLS expressed a unique profile of cytokine secretion, which differed from that of non-HA-FLS, mainly consisting of cytokines involved in innate immunity. We showed that unstable cytokine mRNAs were involved in this process, especially through miRNA complexes as confirmed by DICER silencing. A miRNOME analysis revealed that 30 miRNAs were expressed differently between HA and non-HA-FLS, with most miRNAs involved in inflammatory control pathways or described in certain inflammatory diseases, such as rheumatoid arthritis or lupus. Analysis of transcriptomic networks, impacted by these miRNAs, revealed that protein processes and inflammatory pathways were particularly targeted in LPS-induced FLS, and in particular vascularization and osteoarticular modulation pathways in steady-state FLS. Our study demonstrates that the presence of blood in contact with FLS may induce durable miRNA changes that likely participate in HA pathophysiology.

The Progression of Hemophilic Arthropathy: The Role of Biomarkers.

BACKGROUND: Hemophilia A and B are X-linked congenital bleeding disorders characterized by recurrent hemarthroses leading to specific changes in the synovium and cartilage, which finally result in the destruction of the joint: this process is called hemophilic arthropathy (HA). This review highlights the most prominent molecular biomarkers found in the literature to discuss their potential use in the clinical practice to monitor bleeding, to assess the progression of the HA and the effectiveness of treatments. METHODS: A review of the literature was performed on PubMed and Embase, from 3 to 7 August 2020. Study selection and data extraction were achieved independently by two authors and the following inclusion criteria were determined a priori: English language, available full text and articles published in peer-reviewed journal. In addition, further articles were identified by checking the bibliography of relevant articles and searching for the studies cited in all the articles examined. RESULTS: Eligible studies obtained at the end of the search and screen process were seventy-three (73). CONCLUSIONS: Despite the surge of interest in the clinical use of biomarkers, current literature underlines the lack of their standardization and their potential use in the clinical practice preserving the role of physical examination and imaging in early diagnosis.

Acquired multi-segment foot kinematics in haemophilic children, adolescents and young adults with or without haemophilic ankle arthropathy.

INTRODUCTION AND AIM: The ankle joint remains vulnerable in children with haemophilia and is the primary joint affected. The purpose of this study was to dynamically characterize the segmental foot and ankle kinematics of male children, adolescents and young adults with or without ankle arthropathy. METHODS: The barefoot multi-segment foot kinematics of 70 ankles from 35 haemophilia subjects between 6 and 20 years old were captured with the Rizzoli Multi-Segment Foot Model. Joint damage of the tibiotalar and subtalar joints was scored using the IPSG-MRI score. The feet of patients with or without evidence of ankle arthropathy were compared with those of matched typically developing boys via a nonpaired comparison. The differences between the affected and nonaffected sides of patients with unilateral ankle arthropathy were assessed using a paired comparison. RESULTS: Subjects without arthropathy demonstrated a nonsignificant trend towards a higher frontal plane range of motion (RoM) at the midfoot upon loading response and a lower sagittal plane RoM at the midfoot during midstance. No differences were observed between the affected side group and their matched control group. The affected side of unilaterally affected subjects exhibited a nonsignificant tendency towards a higher frontal plane RoM at the ankle joint upon loading response and terminal stance compared to the healthy side. CONCLUSION: Most patients maintained physiological rocker function of the ankle and had no (mal)adaptive motion patterns in the more distal joints of the foot. Therefore, established structural lesions may remain subclinical with respect to moderate functional activities like walking.

Critical appraisal of the International Prophylaxis Study Group magnetic resonance image scale for evaluating haemophilic arthropathy.

A goal of the International Prophylaxis Study Group (IPSG) is to provide an accurate instrument to measure MRI-based disease severity of haemophilic arthropathy at various time points, so that longitudinal changes in disease severity can be identified to support decisions on treatment management. We review and discuss in this paper the evaluative purpose of the IPSG MRI scale in relation to its development and validation processes so far. We also critically appraise the validity, reliability and responsiveness of using the IPSG MRI scale in different clinical and research settings, and whenever applicable, compare these clinimetric properties of the IPSG MRI scale with those of its precursors, the compatible additive and progressive MRI scales.

The role of Staphylococcus aureus lipoproteins in hematogenous septic arthritis.

Permanent joint dysfunction is a devastating complication in patients with septic arthritis. Staphylococcus aureus (S. aureus) lipoproteins (Lpp), the predominant ligands for TLR2, are known to be arthritogenic and induce bone destruction when introduced directly into the joint. Here, we aim to investigate the importance of S. aureus Lpp and TLR2 in a hematogenous septic arthritis model, which is the most common route of infection in humans. C57BL/6 wild-type and TLR2 deficient mice were intravenously inoculated with S. aureus Newman parental strain or its lipoprotein-deficient Δlgt mutant strain. The clinical course of septic arthritis, radiological changes, and serum levels of cytokines and chemokines, were assessed. Newman strain induced more severe and frequent clinical septic polyarthritis compared to its Δlgt mutant in TLR2 deficient mice, but not in wild-type controls. Bone destruction, however, did not differ between groups. Lpp expression was associated with higher mortality, weight loss as well as impaired bacterial clearance in mouse kidneys independent of TLR2. Furthermore, Lpp expression induced increased systemic pro-inflammatory cytokine and neutrophil chemokine release. Staphylococcal Lpp are potent virulence factors in S. aureus systemic infection independent of host TLR2 signalling. However, they have a limited impact on bone erosion in hematogenous staphylococcal septic arthritis.

In vivo fluorescence molecular tomography of induced haemarthrosis in haemophilic mice: link between bleeding characteristics and development of bone pathology.

BACKGROUND: Haemophilic arthropathy is a chronic and debilitating joint disease caused by recurrent spontaneous joint bleeds in patients with haemophilia. Understanding how characteristics of individual joint bleeds relate to the subsequent development of arthropathy could improve management and prevention of this joint disease. Here, we aimed to explore relations between joint bleed characteristics and development of bone pathology in a mouse model of haemophilic arthropathy by using novel in vivo imaging methodology. METHODS: We characterised induced knee bleeds in a murine model of haemophilic arthropathy by quantitative in vivo fluorescence molecular tomography (FMT) and by measurements of changes in the diameter of the injured knee. Wild-type mice and non-injured haemophilic mice acted as controls. Development of arthropathy was characterised by post mortem evaluation of bone pathology by micro-CT 14 days after bleed-induction. In an in vitro study, we assessed the effect of blood on the quantification of fluorescent signal with FMT. RESULTS: In most injured haemophilic mice, we observed significant loss of trabecular bone, and half of the mice developed pathological bone remodelling. Development of pathological bone remodelling was associated with significantly increased fluorescent signal and diameter of the injured knee just 1 day after induction of the bleed. Further, a correlation between the fluorescent signal 1 day after induction of the bleed and loss of trabecular bone reached borderline significance. In the in vitro study, we found that high concentrations of blood significantly decreased the fluorescent signal. CONCLUSION: Our results add novel insights on the pathogenesis of haemophilic arthropathy and underline the importance of the acute phase of joint bleeds for the subsequent development of arthropathy.

Serological biomarkers in hemophilic arthropathy: Can they be used to monitor bleeding and ongoing progression of blood-induced joint disease in patients with hemophilia?

In patients with hemophilia, levels of uCTX-II and sCS846 increase 5 days after joint hemorrhage with respect to the initial value. In other words, in patients with established hemophilic arthropathy, the aforesaid biomarkers of joint tissue damage augment shortly after the first joint hemorrhage. In patients with hemophilia treated on demand, a correlation has been found between magnetic resonance imaging scores and the CS846 biomarker. Patients with hemophilia having more than one joint with advanced arthropathy have shown high levels of circulating soluble vascular cell adhesion molecule-1 (sVCAM-1). In addition, sVCAM-1 levels in these patients are associated with the severity of hemophilic arthropathy. In patients with hemophilia, cartilage degradation is increased by 25% compared with controls, as measured by some biomarkers (C2M, CTX-II and COMP). Levels of the cartilage degradation enzyme, ADAMTS5, are 10% lower in patients with hemophilia. Bone formation (PINP) is 25% lower in patients with hemophilia, whereas bone resorption (CTXI) is 30% greater. Acute inflammation (hsCRP) is 50% greater, whereas chronic inflammation (CRPM) is 25% lower. The hsCRP/CRPM ratio is 60% higher in patients with hemophilia than in controls. A panel of biomarkers that combines C2M, CRPM and ADAMTS5 can distinguish patients with hemophilia from controls with 85.3% accuracy. No strong correlation between biomarkers and the radiological and physical examination of the joint has been found.

TAFI deficiency causes maladaptive vascular remodeling after hemophilic joint bleeding.

Excessive vascular remodeling is characteristic of hemophilic arthropathy (HA) and may contribute to joint bleeding and the progression of HA. Mechanisms for pathological vascular remodeling after hemophilic joint bleeding are unknown. In hemophilia, activation of thrombin-activatable fibrinolysis inhibitor (TAFI) is impaired, which contributes to joint bleeding and may also underlie the aberrant vascular remodeling. Here, hemophilia A (factor VIII-deficient; FVIII-deficient) mice or TAFI-deficient mice with transient (antibody-induced) hemophilia A were used to determine the role of FVIII and TAFI in vascular remodeling after joint bleeding. Excessive vascular remodeling and vessel enlargement persisted in FVIII-deficient and TAFI-deficient mice, but not in transient hemophilia WT mice, after similar joint bleeding. TAFI-overexpression in FVIII-deficient mice prevented abnormal vessel enlargement and vascular leakage. Age-related vascular changes were observed with FVIII or TAFI deficiency and correlated positively with bleeding severity after injury, supporting increased vascularity as a major contributor to joint bleeding. Antibody-mediated inhibition of uPA also prevented abnormal vascular remodeling, suggesting that TAFI's protective effects include inhibition of uPA-mediated plasminogen activation. In conclusion, the functional TAFI deficiency in hemophilia drives maladaptive vascular remodeling in the joints after bleeding. These mechanistic insights allow targeted development of potentially new strategies to normalize vascularity and control rebleeding in HA.

Molecular Response of Rabbit Menisci to Surgically Induced Hemarthrosis and a Single Intra-Articular Dexamethasone Treatment.

Anterior cruciate ligament reconstructive surgery can restore biomechanical stability, however, such surgery cannot reliably prevent the onset of post-traumatic osteoarthritis. The aim of this study was to elucidate the molecular response that occurs within the menisci following a surgical injury that allows bleeding into the joint space, and then to investigate the effect of dexamethasone (DEX) on this molecular response. Cell viability studies following acute controlled exposure to blood and blood plus DEX were also conducted. Forty-eight New Zealand white rabbits were randomly allocated into control, sham, surgical, and surgical + DEX groups (each group n = 6). Animals were sacrificed at 48 h and 9 weeks, and menisci were harvested. The messenger RNA (mRNA) expression levels for key inflammatory, and degradative proteins, as well as mRNA levels for autophagy pathway molecules were quantified, and statistically significant changes were described. Meniscal cell viability was calculated by incubating groups of medial and lateral menisci in autologous blood, or autologous blood plus DEX for 48 h (each group n = 4; total of eight medial and eight lateral menisci), and then conducting a histological live/dead assay. Results indicated a significant reduction in only medial meniscal cell viability when the tissue was exposed to blood in combination with DEX. A single administration of DEX following surgery significantly suppresses the elevated molecular expression for key inflammatory and degradative markers within menisci at 48 h and 9 weeks post-surgery. In vitro, autologous blood did not affect cell viability, but addition of DEX uniquely impacted the medial menisci. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2043-2052, 2019.

Novel Piperazino-Enaminones Decrease Pro-inflammatory Cytokines Following Hemarthrosis in a Hemophilia Mouse Model.

Hemarthrosis is the primary cause of hemophiliac arthropathy (HA). Pro-inflammatory cytokines are thought to play an important role in the pathogenesis of HA, and thus, anti-cytokine approaches may be used as an adjuvant therapy. A novel series of enaminone compounds (JODI), that contain the N-aryl piperazino motif, have been shown in vitro to reduce pro-inflammatory cytokines and thus may be efficacious in vivo. In this report, we will assess whether JODI can suppress multiple cytokines which might be potentially responsible for joint inflammation in a mouse model of hemarthrosis. The results showed that JODI significantly improved the survival after LPS treatment, and most pro-inflammatory cytokines/chemokines were decreased significantly after JODI administration. In the hemophilia mouse model, hemarthrosis resulted in local cytokine/chemokine changes, represented by elevated pro-inflammatory (IL-6, MCP-1, MIP-1α, MIP-1ß) and pro-angiogenic (VEGF and IL-33) cytokines, and decreased anti-pro-inflammatory cytokines IL-4 and IL-10. The changes were reversed by administration of JODI, which can be used as a novel approach to manage hemophilia arthropathy.

Serum Sclerostin Level and Bone Mineral Density in Pediatric Hemophilic Arthropathy.

OBJECTIVE: To assess serum sclerostin levels in relation to severity of arthropathy and bone mineral density (BMD) in children with hemophilic arthropathy. METHODS: This cross-sectional study included 40 male children suffering from Hemophilia A, and 10 matched healthy controls. Assessment of factor VIII deficiency degree, frequency of bleeding, type of treatment, body mass index (BMI), disease severity using the Hemophilia Joint Health Score (HJHS) and lumbar spine (LS) Z score for bone mineral density (BMD) using dual-energy X-ray absorbiometry was done. Serum sclerostin levels were measured for all patients and controls. RESULTS: Significant difference of serum sclerostin levels between the patient and control groups with Mean ± SD (0.09 ± 0.07 ng/ml) and (0.04 ± 0.01 ng/ml) (P value = 0.028) respectively was found. Significant positive correlations between serum sclerostin levels and the patients' age, and HJHS (P value <0.05) were found, while it had negative correlation with DEXA Z score, not reaching a significant value. LS-BMD-Z score levels ranged from (-4.5 to 1.2), with 15 patients with low BMD Z score (less than -2) representing 37.5% of total patients. CONCLUSIONS: Serum sclerostin levels are elevated in hemophilic children denoting bone metabolism affection and correlates with increased age, and HJHS. Increased levels of serum sclerostin may identify hemophilic patients at high risk for developing osteoporosis.

Hindfoot malalignment in adults with haemophilic ankle arthropathy: The importance of early detection and orthotic treatment.

INTRODUCTION: Haemophilic arthropathy (osteoarthritis secondary to haemophilia) of the ankle may result in painful hindfoot malalignment. PURPOSE: To analyse hindfoot alignment in subjects with haemophilic arthropathy of the ankle and evaluate the response (improvement of pain, function and alignment) to the orthotic treatment prescribed in patients with malalignment. METHODS: The study included 163 patients with haemophilia, all of them over 16 years of age. Hindfoot alignment and footprint were analysed in patients with and without haemophilic arthropathy of the ankle (as determined by the Pettersson score). Response to the use of an orthosis was evaluated at 6 months by means of the AOFAS Ankle-Hindfoot Scale. RESULTS: Fifty-six (59.5%) patients with haemophilic arthropathy presented with concomitant  hindfoot malalignment. The most common abnormality was a valgus alignment combined with a neutral footprint. In 14 cases, valgus was associated with a pes planus or a pes cavus. Only 5 patients without haemophilic arthropathy (7.2%) presented with some form of malalignment. The differences between the groups were statistically significant. The probability of having malalignment increased with the degree of arthropathy. Patients with haemophilic arthropathy and malalignment were treated with an orthosis, with insoles as the most commonly used alternative (86%). Such treatment significantly improved patients' pain and function-related scores on the AOFAS Ankle-Hindfoot Scale. CONCLUSION: Given the high rates of valgus malalignment in subjects with haemophilic arthropathy of the ankle, and the good response rates obtained following individualised orthotic treatment, it seems reasonable to routinely evaluate hindfoot alignment in this group of patients.

Investigating the relationship between the HJHS and HAL in routine clinical practice: A retrospective review.

INTRODUCTION: Comprehensive musculoskeletal assessment for monitoring joint health in haemophilia includes both physical assessment with Haemophilia Joint Health Score (HJHS) and assessment of self-reported function by Haemophilia Activities List (HAL). METHODS: Correlation between physical assessment and joint function was undertaken between HJHS and HAL in patients with SHA and SHB who had both assessments at the same visit over a one-year period. RESULTS: Data from 120 patients (96-SHA/24 = SHB) with a median age 33 years (range 19-73) were included. Median total HJHS was 19, increasing with age: 18-30 years-7, 31-50 years-25 and 51-73 years-44. Similarly, median total HAL score was 80 with decreased function associated with increasing age: 18-30 years-90.4, 31-59 years-71.7, 51-73 years-49.5. Median Total HJHS and HAL demonstrated strong correlation (rs  = 0.66, P < 0.01). Moderate-to-strong correlations were seen across the entire age group between the HJHS LL and UL subtotals and corresponding limb HAL domains. Within age groups, correlations were less significant particularly for the upper UL domains in HAL and the UL HJHS score. The wide range of ROM in joints categorized as markedly affected (ie, ROM loss score = 3) highlights the potential ceiling effect of this domain score and its use in chronically damaged joints. CONCLUSION: HJHS and HAL showed moderate-to-strong correlation with discrepancy in some individual patients. Prospective studies are required to better understand the clinical utility of both especially in severe joint disease where HAL may have a potential advantage.