Biology subjects

Ardeshir, A.

Publications and source records attributed to Ardeshir, A..

6 recordsLinked to original sources

bioRxiv2026

Once yearly cell-based therapy for sustained and dose tunable delivery of monoclonal antibodies

Over 200 monoclonal antibodies (mAbs) are approved for clinical use, yet their therapeutic potential is constrained by dependence on repeated injections or infusions that drive non-adherence, limit access in low-resource settings, and generate peak-trough pharmacokinetics linked to adverse effects and reduced efficacy. Here, we developed an immunomodulatory encapsulated cell-based biologics factory that overcomes mAb instability, immunogenicity, and the fibrotic foreign body response that have limited previous approaches, enabling continuous in situ production of therapeutic antibodies from a single administration. Screening chemically modified alginate biomaterials in immunocompetent mice identified a lead immunomodulatory alginate formulation that sustains stable serum titers of the HIV-neutralizing mAb 3BNC117 for one year. Single-cell RNA sequencing revealed that this formulation promotes a local anti-inflammatory, pro-resolving immune niche that attenuates fibrosis. The platforms versatility was demonstrated by production of thirteen diverse mAbs from an allogeneic cell chassis, with sustained in vivo delivery of a subset including ipilimumab, pembrolizumab, adalimumab, and PGT121. Integration into a retrievable macrodevice enabled on-demand therapeutic termination and re-implantation for dose-proportional tuning. In a non-human primates, subcutaneous implantation maintained stable ipilimumab titers for over six months with no detectable toxicity, anti-drug antibodies, or adverse events, and dose-dependent exposure was confirmed across a three-dose escalation. These results demonstrate a clinically translatable platform offering a practical strategy to replace frequent injections with single-administration therapy.

bioengineering↗

bioRxiv2025

Characterization of immunosenescent alveolar macrophages in rhesus macaques

As the global population ages, understanding the mechanisms underlying age-related diseases becomes increasingly important. Inflammaging, a state of chronic inflammation and immune dysregulation, is a key feature of aging. Macrophages, as master regulators of inflammation, are critical to this process. However, the effects of natural aging on alveolar macrophages (AMs) in the lungs remain poorly understood. In this study, we evaluated AM biology in older compared with young rhesus macaques. We compared cytokine profiles in plasma and bronchoalveolar lavage (BAL) fluid between young and aged macaques and performed single-cell RNA sequencing (scRNA-seq) to characterize age-related transcriptional and functional changes in AMs. Compared to young animals, AMs from aged animals exhibited similar cytokine inflammaging profile observed in the plasma of elderly humans. However, the general decrease of chemokine levels in BAL fluid relative to plasma suggest BAL may not reflect AM status in the lung tissues of rhesus macaques. scRNA-seq data corroborated plasma inflammaging findings, revealing increased inflammatory cytokine responses in AMs from older macaques. The consistent elevation of macrophage migration inhibitory factor (MIF) across plasma, AMs, and BAL fluid marks it as a promising biomarker and potential therapeutic target for age-associated inflammation. scRNA-seq further identified genes and pathways linked to macrophage senescence and turnover, suggesting potential targets for therapeutic intervention. Overall, our findings highlight the essential role of tissue-resident macrophages in pulmonary aging and underscores the need to further investigate their role in age-associated lung disease.

immunology↗

bioRxiv2024

Commensal bacteria inhibit viral infections via a tryptophan metabolite

Clinical outcomes following viral exposures exhibit substantial interindividual variability. Although developing evidence suggests commensal bacteria modulate viral infections, the specific bacteria and mechanisms remain underexplored. Here we define a pathway by which viral infections are inhibited by specific tryptophan-catabolizing bacteria. Using HIV as a model, we bioinformatically associated and experimentally validated several bacterial species that inhibited viral replication. This activity required the aromatic amino acid aminotransferase (ArAT) to metabolize tryptophan into 3-indolelactic acid, which agonizes the aryl hydrocarbon receptor (AhR). Given that AhR regulates multiple viral infections, we found that commensal bacteria also inhibit cytomegalovirus (CMV) in an ArAT-dependent manner. Finally, we confirmed that ArAT is associated with protection against disease outcomes in three distinct human cohorts at-risk for HIV, CMV, or symptomatic COVID-19. Taken together, our results provide mechanistic insight into how commensal bacteria impact viral infections, thereby adding to an emerging field focused on host-commensal-virus interactions.

microbiology↗

bioRxiv2021

Idiopathic chronic diarrhea in rhesus macaques is not associated with enteric viral infections

While recent changes in treatment have reduced the lethality of idiopathic chronic diarrhea (ICD), this condition remains one of the most common causes of rhesus macaque deaths in non-human primate research centers. We compared the eukaryotic viromes in fecal swabs from 52 animals with ICD and 41 healthy animals. Viral metagenomics targeting virus-like particles was used to identify viruses shed by each animal. Five viruses belonging to the Picornaviridae, one to the Caliciviridae, one to the Parvoviridae, and one to the Adenoviridae families were identified. The fraction of reads matching each viral species was then used to estimate and compare viral loads in ICD cases versus healthy controls. None of the eukaryotic viruses detected in fecal swabs were strongly associated with ICD. Other potential causes of ICD are discussed.

microbiology↗

bioRxiv2021

Enteric viruses nucleic acids distribution along the digestive tract of rhesus macaques with idiopathic chronic diarrhea

Idiopathic chronic diarrhea (ICD) is a common clinical condition in captive rhesus macaques, claiming 33% of medical culls (i.e. deaths unrelated to research). Using viral metagenomics we characterized the eukaryotic virome in digestive tract tissues collected at necropsy from nine animals with ICD. We show the presence of multiple viruses in the Parvoviridae and Picornaviridae family. We then compared the distribution of viral reads in the stomach, duodenum, jejunum, ileum, and the proximal, transverse, and distal colons. Tissues and mucosal scraping from the same locations showed closely related results while different gut tissues from the same animal varied widely. Picornavirus reads were generally more abundant in the lower digestive tract, particularly in the descending (distal) colon. Parvoviruses were more abundant in the upper reach particularly in the stomach. In situ hydridization (ISH) of fixed tissues showed punctuated staining for both these RNA and DNA viruses in the distal colon. Parvovirus ISH staining was also detected in the stomach/duodenum/jejunum in distinct oval-shaped structures. Therefore, the location of enteric viral nucleic acid differed widely between different viral families and along the length of the digestive tract.

microbiology↗

bioRxiv2020

A Combination of Two Human Monoclonal Antibodies Limits Fetal Damage by Zika Virus in Macaques

Human infection by Zika virus (ZIKV) during pregnancy can lead to vertical transmission and fetal aberrations, including microcephaly. Prophylactic administration of antibodies can diminish or prevent ZIKV infection in animal models, but whether passive immunization can protect nonhuman primates and their fetuses during pregnancy has not been determined. Z004 and Z021 are neutralizing monoclonal antibodies to domain III of the envelope (EDIII) of ZIKV. Together the two antibodies protect nonpregnant macaques against infection even after Fc modifications to prevent antibody-dependent enhancement in vitro (ADE) and extend their half-lives. Here we report on prophylactic co-administration of the Fc-modified antibodies to pregnant rhesus macaques challenged 3 times with ZIKV during first and second trimester. The two antibodies did not entirely eliminate maternal viremia but limited vertical transmission protecting the fetus from neurologic damage. Thus, maternal passive immunization with two antibodies to EDIII can shield primate fetuses from the harmful effects of ZIKV. Significance statementZika virus (ZIKV) infection during pregnancy can cause fetal abnormalities. Vaccines against ZIKV are under development, but because of potential safety concerns due to disease enhancing antibodies, and the time required by active immunization to induce protective antibodies, there is a need to explore alternative strategies. Recombinant monoclonal antibodies can be modified to prevent enhancement of infection, and thus could be an efficacious and safe alternative to vaccines to confer rapid protection. We show that prophylactic administration of two engineered antibodies, Z004 and Z021, to pregnant macaques partially protects against fetal neurologic damage and limits vertical transmission of ZIKV.

immunology↗