We investigated long-term human coagulation factor IX (huFIX) expression of a novel variant when delivered into mice and rhesus macaques and compared transduction efficiencies using two different ...adeno-associated virus (AAV) capsids. In hemophilic mice injected with KP1-packaged recombinant AAV (rAAV) expressing the hyperactive FIX variant specific activity plasma levels were 10-fold or 2-fold enhanced when compared with wild-type or Padua huFIX injected mice, respectively. In rhesus macaques AAV-LK03 capsid outperformed AAV-KP1 in terms of antigen expression and liver transduction. Two animals from each group showed sustained low-level huFIX expression at 3 months after administration, while one animal from each group lost huFIX mRNA and protein expression over time, despite comparable vector copies. We investigated whether epigenetic differences in the vector episomes could explain this loss of transcription. Cut&Tag analysis revealed lower levels of activating histone marks in the two animals that lost expression. When comparing rAAV genome associated histone modifications in rhesus macaques with those in mice injected with the same vector, the activating histone marks were starkly decreased in macaque-derived episomes. Differential epigenetic marking of AAV genomes may explain different expression profiles in mice and rhesus macaques, as well as the wide dose response variation observed in primates in both preclinical and human clinical trials.
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Kay and colleagues found that transgene expression levels were positively correlated with levels of activating marks deposited on histones associated with the vector genome after dosing mice and rhesus macaques with a huFIX expressing rAAV vector.
The immunologic barriers to successful xenotransplantation are related to the presence of natural anti‐pig antibodies in humans and non‐human primates that bind to antigens expressed on the ...transplanted pig organ (the most important of which is galactose‐α1,3‐galactose Gal), and activate the complement cascade, which results in rapid destruction of the graft, a process known as hyperacute rejection. High levels of elicited anti‐pig IgG may develop if the adaptive immune response is not prevented by adequate immunosuppressive therapy, resulting in activation and injury of the vascular endothelium. The transplantation of organs and cells from pigs that do not express the important Gal antigen (α1,3‐galactosyltransferase gene‐knockout GTKO pigs) and express one or more human complement‐regulatory proteins (hCRP, e.g., CD46, CD55), when combined with an effective costimulation blockade‐based immunosuppressive regimen, prevents early antibody‐mediated and cellular rejection. However, low levels of anti‐non‐Gal antibody and innate immune cells and/or platelets may initiate the development of a thrombotic microangiopathy in the graft that may be associated with a consumptive coagulopathy in the recipient. This pathogenic process is accentuated by the dysregulation of the coagulation‐anticoagulation systems between pigs and primates. The expression in GTKO/hCRP pigs of a human coagulation‐regulatory protein, for example, thrombomodulin, is increasingly being associated with prolonged pig graft survival in non‐human primates. Initial clinical trials of islet and corneal xenotransplantation are already underway, and trials of pig kidney or heart transplantation are anticipated within the next few years.
Xenotransplantation has the potential to alleviate the organ shortage that prevents many patients with end‐stage renal disease from enjoying the benefits of kidney transplantation. Despite ...significant advances in other models, pig‐to‐primate kidney xenotransplantation has met limited success. Preformed anti‐pig antibodies are an important component of the xenogeneic immune response. To address this, we screened a cohort of 34 rhesus macaques for anti‐pig antibody levels. We then selected animals with both low and high titers of anti‐pig antibodies to proceed with kidney transplant from galactose‐α1,3‐galactose knockout/CD55 transgenic pig donors. All animals received T‐cell depletion followed by maintenance therapy with costimulation blockade (either anti‐CD154 mAb or belatacept), mycophenolate mofetil, and steroid. The animal with the high titer of anti‐pig antibody rejected the kidney xenograft within the first week. Low‐titer animals treated with anti‐CD154 antibody, but not belatacept exhibited prolonged kidney xenograft survival (>133 and >126 vs. 14 and 21 days, respectively). Long‐term surviving animals treated with the anti‐CD154‐based regimen continue to have normal kidney function and preserved renal architecture without evidence of rejection on biopsies sampled at day 100. This description of the longest reported survival of pig‐to‐non‐human primate kidney xenotransplantation, now >125 days, provides promise for further study and potential clinical translation.
The posterior parietal cortex (PPC) integrates multisensory and motor‐related information for generating and updating body representations and movement plans. We used retrograde transneuronal ...transfer of rabies virus combined with a conventional tracer in macaque monkeys to identify direct and disynaptic pathways to the arm‐related rostral medial intraparietal area (MIP), the ventral lateral intraparietal area (LIPv), belonging to the parietal eye field, and the pursuit‐related lateral subdivision of the medial superior temporal area (MSTl). We found that these areas receive major disynaptic pathways via the thalamus from the nucleus of the optic tract (NOT) and the superior colliculus (SC), mainly ipsilaterally. NOT pathways, targeting MSTl most prominently, serve to process the sensory consequences of slow eye movements for which the NOT is the key sensorimotor interface. They potentially contribute to the directional asymmetry of the pursuit and optokinetic systems. MSTl and LIPv receive feedforward inputs from SC visual layers, which are potential correlates for fast detection of motion, perceptual saccadic suppression and visual spatial attention. MSTl is the target of efference copy pathways from saccade‐ and head‐related compartments of SC motor layers and head‐related reticulospinal neurons. They are potential sources of extraretinal signals related to eye and head movement in MSTl visual‐tracking neurons. LIPv and rostral MIP receive efference copy pathways from all SC motor layers, providing online estimates of eye, head and arm movements. Our findings have important implications for understanding the role of the PPC in representation updating, internal models for online movement guidance, eye‐hand coordination and optic ataxia.
With the use of rabies retrograde transneuronal tracing, we demonstrate in non‐human primates that cortical areas MSTl, LIPv and rostral MIP receive major ascending disynaptic pathways from the nucleus of the optic tract (NOT) and visual and motor layers of the superior colliculus (SC). Pathways from the NOT and SC visual layers serve to process the sensory consequences of slow eye movements for which the NOT is the key sensorimotor interface and are potential correlates for fast detection of motion, perceptual saccadic suppression and visual spatial attention. MSTl is the target of efference copy pathways from saccade‐ and head‐related compartments of SC upper motor layers, while LIPv and rostral MIP receive efference copy pathways from all SC motor layers and the underlying reticular formation, providing an online estimate of eye, head and arm movements.
This paper examines the agency of African elephants as important actors in the political ecology of human–elephant conflict, and in shaping the politics of land in post‐colonial Kenya. The paper is ...based on field research in Laikipia, northern Kenya. It considers the role of elephants, with their size, sagacity, hunger, mobility and complex interactions with people, as powerful actors in shared landscapes, and therefore in the politics surrounding their own conservation. The paper uses spatial data and interviews to explore elephant behaviour and movements through the landscape and their interactions with people, and explore the way in which those interactions affect the separation of “animal spaces” set aside for conservation and the “beastly places” of smallholder farming and crop‐raiding, and the conflict and transgressions involved when elephants cross from one to the other. The elephant is a lively actor in the inter‐species power play of Laikipia, and in the politics of conservation and of land. A mutually respectful multispecies politics in northern Kenya demands a clear understanding and acceptance of the needs of elephants.
The goal of this review is to provide further understanding of increased vascular stiffness with aging, and how it contributes to the adverse effects of major human diseases. Differences in stiffness ...down the aortic tree are discussed, a topic requiring further research, because most prior work only examined one location in the aorta. It is also important to understand the divergent effects of increased aortic stiffness between males and females, principally due to the protective role of female sex hormones prior to menopause. Another goal is to review human and non-human primate data and contrast them with data in rodents. This is particularly important for understanding sex differences in vascular stiffness with aging as well as the changes in vascular stiffness before and after menopause in females, as this is controversial. This area of research necessitates studies in humans and non-human primates, since rodents do not go through menopause. The most important mechanism studied as a cause of age-related increases in vascular stiffness is an alteration in the vascular extracellular matrix resulting from an increase in collagen and decrease in elastin. However, there are other mechanisms mediating increased vascular stiffness, such as collagen and elastin disarray, calcium deposition, endothelial dysfunction, and the number of vascular smooth muscle cells (VSMCs). Populations with increased longevity, who live in areas called "Blue Zones," are also discussed as they provide additional insights into mechanisms that protect against age-related increases in vascular stiffness. Such increases in vascular stiffness are important in mediating the adverse effects of major cardiovascular diseases, including atherosclerosis, hypertension and diabetes, but require further research into their mechanisms and treatment.
The vast majority of cerebral stroke cases are caused by transient or permanent occlusion of a cerebral blood vessel (“
ischemic stroke
”) eventually leading to brain infarction. The final infarct ...size and the neurological outcome depend on a multitude of factors such as the duration and severity of ischemia, the existence of collateral systems and an adequate systemic blood pressure, etiology and localization of the infarct, but also on age, sex, comorbidities with the respective multimedication and genetic background. Thus, ischemic stroke is a highly complex and heterogeneous disorder. It is immediately obvious that experimental models of stroke can cover only individual specific aspects of this multifaceted disease. A basic understanding of the principal molecular pathways induced by ischemia-like conditions comes already from in vitro studies. One of the most frequently used in vivo models in stroke research is the endovascular suture or filament model in rodents with occlusion of the middle cerebral artery (MCA), which causes reproducible infarcts in the MCA territory. It does not require craniectomy and allows reperfusion by withdrawal of the occluding filament. Although promptly restored blood flow is far from the pathophysiology of spontaneous human stroke, it more closely mimics the therapeutic situation of mechanical thrombectomy which is expected to be increasingly applied to stroke patients. Direct transient or permanent occlusion of cerebral arteries represents an alternative approach but requires craniectomy. Application of endothelin-1, a potent vasoconstrictor, allows induction of transient focal ischemia in nearly any brain region and is frequently used to model lacunar stroke. Circumscribed and highly reproducible cortical lesions are characteristic of photothrombotic stroke where infarcts are induced by photoactivation of a systemically given dye through the intact skull. The major shortcoming of this model is near complete lack of a penumbra. The two models mimicking human stroke most closely are various embolic stroke models and spontaneous stroke models. Closeness to reality has its price and goes along with higher variability of infarct size and location as well as unpredictable stroke onset in spontaneous models versus unpredictable reperfusion in embolic clot models.
•Non-human influencers include animals, plants, objects, toys, mascots, robots, licensed characters, and virtual influencers.•More-than-human netnography reveals key source and content factors that ...drive user engagement.•Non-human influencers engage social media users by emulating the conventions of ‘being human’.•Source credibility, product-endorser fit and parasocial relationship can be applied in the non-human context.
This study examines the phenomenon of non-human influencers on social media, including living entities such as animals and plants, as well as non-living entities such as objects, toys, mascots, robots, licensed characters, and virtual influencers. Using more-than-human netnography, the study analyses 1112 user comments from 52 Instagram posts to identify and describe the key source and content factors that drive user engagement with non-human influencers. The findings suggest that users engage with non-human influencers for a variety of reasons, including entertainment value, emotional connection, and educational content. The study contributes to the conceptualisation of non-human influencers by proposing a framework mapping the engagement factors and presenting research questions for future exploration. The implications of this study are significant for brands and businesses seeking to work with non-human influencers in their marketing strategies.
Generation of genetically uniform non-human primates may help to establish animal models for primate biology and biomedical research. In this study, we have successfully cloned cynomolgus monkeys ...(Macaca fascicularis) by somatic cell nuclear transfer (SCNT). We found that injection of H3K9me3 demethylase Kdm4d mRNA and treatment with histone deacetylase inhibitor trichostatin A at one-cell stage following SCNT greatly improved blastocyst development and pregnancy rate of transplanted SCNT embryos in surrogate monkeys. For SCNT using fetal monkey fibroblasts, 6 pregnancies were confirmed in 21 surrogates and yielded 2 healthy babies. For SCNT using adult monkey cumulus cells, 22 pregnancies were confirmed in 42 surrogates and yielded 2 babies that were short-lived. In both cases, genetic analyses confirmed that the nuclear DNA and mitochondria DNA of the monkey offspring originated from the nucleus donor cell and the oocyte donor monkey, respectively. Thus, cloning macaque monkeys by SCNT is feasible using fetal fibroblasts.
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•Somatic cell nuclear transfer (SCNT) using fetal fibroblasts yielded two live monkeys•Epigenetic modulators promoted development and pregnancy rate of SCNT embryos•SCNT using adult cumulus cells yielded live births of monkeys that were short-lived•Genetic analysis confirmed the clonal origin of the SCNT monkey offspring
Generation of cloned cynomolgus monkeys by somatic cell nuclear transfer using fetal monkey fibroblasts.
The major medical advances in our knowledge of the human leukocyte antigen (HLA) system have allowed us to uncover several gaps in our understanding of alloimmunity. Although the non-HLA system has ...long sparked the interest of the transplant community, recognition of the role of immunity to non-HLA antigenic targets has only emerged recently. In this review, we will provide a comprehensive summary of the paradigm-changing concept of immunity to the non-HLA angiotensin II type 1 receptor (AT1R), discovered by Duška Dragun et al., that began from careful bedside clinical observations, to validated detection of anti-AT1R antibodies and lead to clinical intervention. This scientific approach has also allowed the recognition of broader pathogenicity of anti-AT1R antibodies across multiple organ transplants and in other human diseases, the integration of both non-HLA and HLA systems to understand their immunologic effects on organ allografts, and the identification of future directions for therapeutic intervention to modulate immunity to AT1R. Rationally designed successful interventions to target AT1R system provide an exemplar for other non-HLA antibodies to cross borders between medical specialties, will generate new avenues in translational research beyond transplantation, and will foster the development of new and reliable tools to improve our understanding of non-HLA immunity and ultimately allow us to improve patient care.