bioRxiv Science⌕ Search

Biology subjects

Hasty, K. A.

Publications and source records attributed to Hasty, K. A..

4 recordsLinked to original sources

A programmable arthritis-specific receptor for guided articular cartilage regenerative medicine

ObjectiveInvestigational cell therapies have been developed as disease-modifying agents for the treatment of osteoarthritis (OA), including those that inducibly respond to inflammatory factors driving OA progression. However, dysregulated inflammatory cascades do not specifically signify the presence of OA. Here, we deploy a synthetic receptor platform that regulates cell behaviors in an arthritis-specific fashion to confine transgene expression to sites characterized by cartilage degeneration. MethodsAn scFv specific for type II collagen (CII) was used to produce a synthetic Notch (synNotch) receptor that enables "CII-synNotch" mesenchymal stromal cells (MSCs) to recognize CII fibers exposed in damaged cartilage. Engineered cell activation by both CII-treated culture surfaces and on primary tissue samples was measured via inducible reporter transgene expression. TGF{beta}3-expressing cells were assessed for cartilage anabolic gene expression via qRT-PCR. In a co-culture with CII-synNotch MSCs engineered to express IL-1Ra, ATDC5 chondrocytes were stimulated with IL-1, and inflammatory responses of ATDC5s were profiled via qRT-PCR and an NF-kB reporter assay. ResultsCII-synNotch MSCs are highly responsive to CII, displaying activation ranges over 40-fold in response to physiologic CII inputs. CII-synNotch cells exhibit the capacity to distinguish between healthy and damaged cartilage tissue and constrain transgene expression to regions of exposed CII fibers. Receptor-regulated TGF{beta}3 expression resulted in upregulation of Acan and Col2a1 in MSCs, and inducible IL-1Ra expression by engineered CII-synNotch MSCs reduced pro-inflammatory gene expression in chondrocytes. ConclusionThis work demonstrates proof-of-concept that the synNotch platform guides MSCs for spatially regulated, disease-dependent delivery of OA-relevant biologic drugs.

bioengineering↗

Albumin-binding RNAi Conjugate for Carrier Free Treatment of Arthritis

Osteoarthritis (OA) and rheumatoid arthritis (RA) are joint diseases that are associated with pain and lost quality of life. No disease modifying OA drugs are currently available. RA treatments are better established but are not always effective and can cause immune suppression. Here, an MMP13-selective siRNA conjugate was developed that, when delivered intravenously, docks onto endogenous albumin and promotes preferential accumulation in articular cartilage and synovia of OA and RA joints. MMP13 expression was diminished upon intravenous delivery of MMP13 siRNA conjugates, consequently decreasing multiple histological and molecular markers of disease severity, while also reducing clinical manifestations such as swelling (RA) and joint pressure sensitivity (RA and OA). Importantly, MMP13 silencing provided more comprehensive OA treatment efficacy than standard of care (steroids) or experimental MMP inhibitors. These data demonstrate the utility of albumin hitchhiking for drug delivery to arthritic joints, and establish the therapeutic utility of systemically delivered anti-MMP13 siRNA conjugates in OA and RA. Editorial summaryLipophilic siRNA conjugates optimized for albumin binding and "hitchhiking" can be leveraged to achieve preferential delivery to and gene silencing activity within arthritic joints. Chemical stabilization of the lipophilic siRNA enables intravenous siRNA delivery without lipid or polymer encapsulation. Using siRNA sequences targeting MMP13, a key driver of arthritis-related inflammation, albumin hitchhiking siRNA diminished MMP13, inflammation, and manifestations of osteoarthritis and rheumatoid arthritis at molecular, histological, and clinical levels, consistently outperforming clinical standards of care and small molecule MMP antagonists.

bioengineering↗

Robust Characterization of Non-Invasive Post-Traumatic Osteoarthritis Mouse Model

ObjectiveBiochemical and molecular changes involved in the pathophysiology of post-traumatic arthritis (PTOA) have not been fully understood. This study used non-invasive mouse models to study biochemical, biomechanical and pain-related behavior changes induced in mice following repetitive mechanical knee loading. Mouse models were used to reflect the effects of the early stages of PTOA in humans. MethodsForty-eight twelve week old male mice were obtained for three groups: normal control without mechanical loading, trauma (24 hours after loading), and PTOA (early OA) groups. For the non-invasive PTOA mouse model, cyclic comprehensive loading (9 N) was applied on the left knee joint of each mouse. Biochemical and molecular changes induced by mechanical loading were analyzed after loading was completed. Blood and cartilage were collected and further examined using gene expression analysis. Grading of the tissue sections was completed using the osteoarthritis research society international (OARSI) scale. Biomechanical features of mechanically loaded knee joints were determined after 24 hours (Trauma) and three weeks (PTOA) post-mechanical loading sessions to examine the development of PTOA, respectively. ResultsThe loaded left knee joint showed a greater ROS/RNS signal than the right knee that was not loaded. There was an increase in cartilage damage and MMP activity in the affected knee as the intensity of MabCII680 and MMP750 signal increased in the mechanical loaded joints as compared to unloaded control knee joints. There was also an increase in the difference of viscoelastic energy dissipation ability (tan {delta}) in PTOA. The OA score increased significantly in mechanically loaded knee joints. ConclusionThis study showed that biomechanical, biochemical, and behavioral characteristics of the murine PTOA groups are significantly different from the control group. These results validate that the current mouse model can be used for translational studies to examine PTOA.

animal behavior and cognition↗

Matrix-targeted Nanoparticles for MMP13 RNA Interference Blocks Post-Traumatic Osteoarthritis.

Osteoarthritis (OA) is a debilitating and prevalent chronic disease, but there are no approved disease modifying OA drugs (DMOADs), only pharmaceuticals for pain management. OA progression, particularly for post-traumatic osteoarthritis (PTOA), is associated with inflammation and enzymatic degradation of the extracellular matrix. In particular, Matrix Metalloproteinase 13 (MMP13) breaks down collagen type 2 (CII), a key structural component of cartilage extracellular matrix, and consequently, matrix degradation fragments perpetuate inflammation and a degenerative cycle that leads to progressive joint pathology. Here, we tested targeted delivery of endosome-escaping, MMP13 RNA interference (RNAi) nanoparticles (NPs) as a DMOAD. The new targeting approach pursued here deviates from the convention of targeting specific cell types (e.g., through cell surface receptors) and instead leverages a monoclonal antibody (mAbCII) that targets extracellular CII that becomes uniquely accessible at early OA focal defects. Targeted mAbCII-siNPs create an in situ NP depot for retention and potent activity within OA joints. The mAbCII-siNPs loaded with MMP13 siRNA (mAbCII-siNP/siMMP13) potently suppressed MMP13 expression (95% silencing) in TNF-stimulated chondrocytes in vitro, and the targeted mAbCII-siNPs had higher binding to trypsin-damaged porcine cartilage than untargeted control NPs. In an acute mechanical injury mouse model of PTOA, mAbCII-siNP/siMMP13 achieved 80% reduction in MMP13 expression (p = 0.00231), whereas a non-targeted control achieved only 55% silencing. In a more severe, PTOA model, weekly mAbCII-siNP/siMMP13 long-term treatment provided significant protection of cartilage integrity (0.45+/- .3 vs 1.6+/-.5 on the OARSI scale; p=0.0166), and overall joint structure (1.3+/-.6 vs 2.8+/-.2 on the Degenerative Joint Disease scale; p<0.05). Intra-articular mAbCII-siNPs better protected articular cartilage (OARSI score) relative to either single or weekly treatment with the clinical gold stand steroid treatment methylprednisolone. Finally, multiplexed gene expression analysis of 254 inflammation-related genes showed that MMP13 inhibition suppressed clusters of genes associated with tissue restructuring, angiogenesis (associated with synovial inflammation and thickening), innate immune response, and proteolysis. This work establishes the new concept of targeting unique local extracellular matrix signatures to sustain retention and increase delivery efficacy of biologics with intracellular activity and also validates the promise of MMP13 RNAi as a DMOAD in a clinically-relevant therapeutic context. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=148 SRC="FIGDIR/small/925321v1_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@1803795org.highwire.dtl.DTLVardef@c1254dorg.highwire.dtl.DTLVardef@78233eorg.highwire.dtl.DTLVardef@151d96f_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOAbstract Figure:C_FLOATNO PTOA targeted delivery of MMP13 siRNA to block disease progressionThe top left schematic illustrates the progression (left to right) from healthy knee joint, through inflammation induction following traumatic injury, to cartilage loss and degenerative joint disease (including synovial response). Degradation of cartilage enhances inflammation, inducing a degenerative cycle (middle right). The bottom of the graphic illustrates the concept of the matrix targeted nanocarriers for enhanced retention and activity of MMP13 siRNA at sites of cartilage injury. C_FIG

bioengineering↗