skip to main content


Title: Administration of FVIII-Expressing Human Placental Cells to Juvenile Sheep Yields Multi- Organ Engraftment, Therapeutic Plasma FVIII Levels and Alter Immune Signaling Pathways to Evade FVIII Inhibitor Induction
Administration of FVIII-Expressing Human Placental Cells to Juvenile Sheep Yields Multi-Organ Engraftment, Therapeutic Plasma FVIII Levels and Alter Immune Signaling Pathways to Evade FVIII Inhibitor Induction 63rd ASH Annual Meeting and Exposition, December 11-14, 2021, Georgia World Congress Center, Atlanta, GA Program: Oral and Poster Abstracts Session: 801. Gene Therapies: Poster III Hematology Disease Topics & Pathways: Bleeding and Clotting, Biological, Translational Research, Hemophilia, Genetic Disorders, Immune Mechanism, Diseases, Gene Therapy, Therapies, Adverse Events, Biological Processes, Transplantation Monday, December 13, 2021, 6:00 PM-8:00 PM We have previously reported that normal juvenile sheep that received weekly intravenous (IV) infusions of human (n=3) or an expression/secretion-optimized, bioengineered human/porcine hybrid (ET3) FVIII protein (n=3) for 5 weeks (20 IU/kg) developed anti-FVIII inhibitory antibodies (10-116 BU, and IgG titers of 1:20–1:245) by week 3 of infusion. By contrast, the IV infusion, or IP administration, of human placental mesenchymal cells (PLC) transduced with a lentiviral vector encoding a myeloid codon-optimized ET3 transgene (PLC-mcoET3) to produce high levels of ET3 protein (4.9-6IU/10^6 cells/24h) enabled the delivery of FVIII without eliciting antibodies, despite using PLC-mcoET3 doses that provided ~20-60 IU/kg ET3 each 24h to mirror the amount of FVIII protein infused. In addition, we showed that the route of PLC-mcoET3 administration (IP vs IV) did not impact the resultant plasma FVIII levels, with animals in these two groups exhibiting mean increases in FVIII activity (quantified by aPTT) of 30.9% and 34.2%, respectively, at week 15 post-treatment. Here, we investigated whether the sites and levels of PLC-mcoET3 engraftment were dependent upon the route of administration and performed s sheep-specific multiplexed transcriptomic analysis (NanoString) to define the immune signaling pathways that thwarted FVIII/ET3 protein immune response when ET3 was delivered through PLC. Tissue samples were collected from various organs at euthanasia and RT-qPCR performed using primers specific to the mcoET3 transgene, to the human housekeeping transcript GAPDH, and to sheep GAPDH, to quantify PLC-mcoET3 tissue engraftment, and normalize the results. RT-qPCR demonstrated PLC-mcoET3 engrafted, in both IP and IV groups, in all the organs evaluated (liver, lung, lymph nodes, thymus, and spleen). Animals that received PLC-mcoET3 via the IP route displayed higher overall levels of engraftment than their IV counterparts. The spleen was the preferential organ of engraftment for both IP and IV groups (IP:2.41±1.97%; IV: 0.64±0.54%). The IP group exhibited significantly higher engraftment in the left lobe of the liver (IP: 1.36±0.35%; IV: 0.041±0.022%), which was confirmed by immunohisto-chemistry (IHC) with an antibody to the human nuclear antigen Ku80 and ImageJ analysis (IP:5.24±3.36%; IV: 0±0). Of note is that the IP route resulted in higher levels of engraftment in the thymus, while IV infusion yielded higher levels of PLC-mcoET3 in lymph nodes. Analysis of H&E-stained tissues demonstrated they were devoid of any abnormal histologic changes and exhibited no evidence of hyperplasia or neoplasia, supporting the safety of the cell platform, irrespective of the route of administration. To date, NanoString analysis of PBMC collected at day 0, week 1, and week 5 post-infusion demonstrated that animals who received FVIII protein had upregulation of UBA5 and BATF, genes involved in antigen processing and Th17 signaling pathways, respectively. Although both IV and IP recipients of PLC-mcoET3 also had an increase in BATF, the IV group exhibited upregulation of BTLA, a gene involved in immune-tolerance, and downregulation of NOTCH and DDL1, involved in T cell differentiation, as well as MAPK12 and PLCG1, genes involved in proinflammatory cytokine regulation and T signaling within the Th17 signature. In IP recipients, BTLA, NOTCH, and DLL1 were all downregulated. Since ET3-reactive Th1 cells were not present in any of the treated animals, it is possible that the Th17 cells are responsible for the inhibitory antibodies seen in the juvenile sheep treated with FVIII/ET3 protein, while in animals receiving PLC-mcoET3, downregulation of genes involved in T cell differentiation and proinflammatory cytokine signaling keeps the immune system in check to avoid an immune response. Disclosures: Doering: Expression Therapeutics: Divested equity in a private or publicly-traded company in the past 24 months. Spencer: Expression Therapeutics: Divested equity in a private or publicly-traded company in the past 24 months.  more » « less
Award ID(s):
1659663
NSF-PAR ID:
10313915
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
ASH
ISSN:
1296-5952
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Systemic administration of immune checkpoint blockade (ICB) monoclonal antibodies (mAbs) can unleash antitumor functions of T cells but is associated with variable response rates and off-target toxicities. We hypothesized that antitumor efficacy of ICB is limited by the minimal accumulation of mAb within tissues where antitumor immunity is elicited and regulated, which include the tumor microenvironment (TME) and secondary lymphoid tissues. In contrast to systemic administration, intratumoral and intradermal routes of administration resulted in higher mAb accumulation within both the TME and its draining lymph nodes (LNs) or LNs alone, respectively. The use of either locoregional administration route resulted in pronounced T cell responses from the ICB therapy, which developed in the secondary lymphoid tissues and TME of treated mice. Targeted delivery of mAb to tumor-draining lymph nodes (TdLNs) alone was associated with enhanced antitumor immunity and improved therapeutic effects compared to conventional systemic ICB therapy, and these effects were sustained at reduced mAb doses and comparable to those achieved by intratumoral administration. These data suggest that locoregional routes of administration of ICB mAb can augment ICB therapy by improving immunomodulation within TdLNs.

     
    more » « less
  2. Abstract

    Recent clinical studies show activating multiple innate immune pathways drives robust responses in infection and cancer. Biomaterials offer useful features to deliver multiple cargos, but add translational complexity and intrinsic immune signatures that complicate rational design. Here a modular adjuvant platform is created using self‐assembly to build nanostructured capsules comprised entirely of antigens and multiple classes of toll‐like receptor agonists (TLRas). These assemblies sequester TLR to endolysosomes, allowing programmable control over the relative signaling levels transduced through these receptors. Strikingly, this combinatorial control of innate signaling can generate divergent antigen‐specific responses against a particular antigen. These assemblies drive reorganization of lymph node stroma to a pro‐immune microenvironment, expanding antigen‐specific T cells. Excitingly, assemblies built from antigen and multiple TLRas enhance T cell function and antitumor efficacy compared to ad‐mixed formulations or capsules with a single TLRa. Finally, capsules built from a clinically relevant human melanoma antigen and up to three TLRa classes enable simultaneous control of signal transduction across each pathway. This creates a facile adjuvant design platform to tailor signaling for vaccines and immunotherapies without using carrier components. The modular nature supports precision juxtaposition of antigen with agonists relevant for several innate receptor families, such as toll, STING, NOD, and RIG.

     
    more » « less
  3. BACKGROUND Diverse organisms, from archaea and bacteria to plants and humans, use receptor systems to recognize both pathogens and dangerous self-derived or environmentally derived stimuli. These intricate, well-coordinated immune systems, composed of innate and adaptive components, ensure host survival. In the late 20th century, researchers identified the Toll/interleukin-1/resistance gene (TIR) domain as an evolutionarily conserved component of animal and plant innate immune systems. Today, TIR-domain proteins are known to be broadly distributed across the tree of life. The TIR domain was first recognized as an adaptor for the assembly of macromolecular signaling complexes in mammalian innate immune pathways. Work on axon degeneration in animals—as well as on plant, archaeal, and bacterial immune systems—has uncovered additional enzymatic activities for TIR domains. ADVANCES Mammalian axons initiate a self-destruct program upon injury and during disease that is mediated by the sterile alpha and TIR motif containing 1 (SARM1) protein. The SARM1 TIR domain enzymatically consumes the essential metabolic cofactor nicotinamide adenine dinucleotide (NAD + ) to promote axonal death. Identification of the SARM1 NAD + -consuming enzyme (NADase) revealed that TIR domains can function as enzymes. Given the evolutionary conservation of TIR domains, studies investigated whether the SARM1 TIR NADase was also conserved. Indeed, bacteria, archaea, and plant TIR domains possess NADase activity. In prokaryotes, TIR NADase activity is found in an ancient antiphage immune system. In plants, identification of TIR NADase activity and linkage of TIR enzymatic products to downstream signaling components addressed the question of how nucleotide-binding, leucine-rich repeat (NLR) receptors trigger hypersensitive cell death during an immune response. Studies in plants show that their TIR domains can cleave nucleic acids and possess 2′,3′ cyclic adenosine monophosphate (2′,3′-cAMP) and 2′,3′ cyclic guanosine monophosphate (2′,3′-cGMP) synthetase activity that aids cell death programs in plant innate immunity. Thus, TIR domains constitute an ancient family of enzymes that are activated in immune and cell death pathways. OUTLOOK The discovery of TIR-domain enzyme activities carries implications for innate immunity and neurodegeneration. The identification of the SARM1 NADase defined a drug target for a wide number of neurodegenerative diseases that is being exploited in both preclinical and clinical studies. Hyperactive mutations in the SARM1 NADase have been discovered in amyotrophic lateral sclerosis (ALS) patients. Future work will seek to clarify the contribution of the SARM1 axon degeneration pathway to ALS pathogenesis. NAD + biology influences cellular processes from metabolism to DNA repair to aging. How TIR enzymes influence the NAD + metabolome and its associated pathways in bacteria, archaea, plants, and animals will be an exciting area for upcoming investigation. The discovery of the diversity of TIR enzymatic products is revealing signaling pathways across kingdoms. Discovery of TIR enzymatic function in plants and animals may yet inspire studies of enzymatic functions for Toll-like receptors in animals. We anticipate that cross-kingdom studies of TIR-domain function will guide interventions that will span the tree of life, from treating human neurodegenerative disorders and bacterial infections to preventing plant diseases. Conserved TIR-domain enzymatic activity. TIR-domain proteins from prokaryotes and eukaryotes cleave NAD + into nicotinamide (Nam), ADP-ribose (ADPR), cyclic ADP-ribose (cADPR), isomers of cyclic ADP-ribose (2′ or 3′cADPR), and related molecules [e.g., phosphoribosyl adenosine monophosphate (pRib-AMP)]. Plant TIR domains also possess a nuclease activity, can degrade DNA and RNA, and can function as a 2′,3′-cAMP or 2′,3′-cGMP synthetase. TIR enzymatic activity drives cell death and immune pathways across kingdoms. TIR activity can kill cells directly through NAD + depletion or indirectly using enzymatic products as signal molecules. The representative TIR domain structure shown here is Protein Data Bank ID 6O0Q. EDS1, enhanced disease susceptibility 1; ThsA, Thoeris A. 
    more » « less
  4. Objective

    To obtain the comprehensive transcriptome profile of human citrulline‐specific B cells from patients with rheumatoid arthritis (RA).

    Methods

    Citrulline‐ and hemagglutinin‐specific B cells were sorted by flow cytometry using peptide–streptavidin conjugates from the peripheral blood ofRApatients and healthy individuals. The transcriptome profile of the sorted cells was obtained byRNA‐sequencing, and expression of key protein molecules was evaluated by aptamer‐basedSOMAscan assay and flow cytometry. The ability of these proteins to effect differentiation of osteoclasts and proliferation and migration of synoviocytes was examined by in vitro functional assays.

    Results

    Citrulline‐specific B cells, in comparison to citrulline‐negative B cells, from patients withRAdifferentially expressed the interleukin‐15 receptor α (IL‐15Rα) gene as well as genes related to protein citrullination and cyclicAMPsignaling. In analyses of an independent cohort of cyclic citrullinated peptide–seropositiveRApatients, the expression ofIL‐15Rα protein was enriched in citrulline‐specific B cells from the patients’ peripheral blood, and surprisingly, all B cells fromRApatients were capable of producing the epidermal growth factor ligand amphiregulin (AREG). Production ofAREGdirectly led to increased migration and proliferation of fibroblast‐like synoviocytes, and, in combination with anti–citrullinated protein antibodies, led to the increased differentiation of osteoclasts.

    Conclusion

    To the best of our knowledge, this is the first study to document the whole transcriptome profile of autoreactive B cells in any autoimmune disease. These data identify several genes and pathways that may be targeted by repurposing severalUSFood and Drug Administration–approved drugs, and could serve as the foundation for the comparative assessment of B cell profiles in other autoimmune diseases.

     
    more » « less
  5. Abstract

    Bone marrow stem cells (BMSCs) are a promising strategy for cardiac regenerative therapy for myocardial infarction (MI). However, cell transplantation has to overcome a number of hurdles, such as cell quality control, clinical practicality, low cell retention/engraftment, and immune reactions when allogeneic cells are used. Bispecific antibodies (BsAbs) have been developed as potential agents in cancer immunotherapy but their application is sparse in cardiovascular diseases. In the present study, BsAbs are designed by chemical cycloaddition of F(ab′)2fragments from monoclonal anti‐CD34 and anti‐ cardiac myosin heavy chain (CMHC) antibodies, which specifically targets circulating CD34‐positive cells and injured cardiomyocytes simultaneously. It is hypothesized that intravenous administration of stem cell re‐directing (SCRD) BsAbs (anti‐CD34‐F(ab′)2–anti‐CMHC‐F(ab′)2) can home endogenous BMSCs to the injured heart for cardiac repair. The in vivo studies in a mouse model with heart ischemia/reperfusion (I/R) injury demonstrate the safety and therapeutic potency of SCRD BsAb, which supports cardiac recovery by reducing scarring, promoting angiomyogenesis, and boosting cardiac function.

     
    more » « less