Biology subjects

Ericsen, A. J.

Publications and source records attributed to Ericsen, A. J..

3 recordsLinked to original sources

bioRxiv2020

Identification of a lymphocyte minor histocompatibility antigen in Mauritian cynomolgus macaques

Allogeneic hematopoietic stem cell transplantation can lead to dramatic reductions in human immunodeficiency virus (HIV) reservoirs. This effect is mediated in part by donor T cells that recognize lymphocyte-expressed minor histocompatibility antigens (mHAgs). The potential to mark malignant and latently infected cells for destruction makes mHAgs attractive targets for cellular immunotherapies. However, testing such HIV reservoir reduction strategies will likely require preclinical studies in nonhuman primates (NHPs). In this study, we used a combination of alloimmunization, whole exome sequencing, and bioinformatics to identify a mHAg in Mauritian cynomolgus macaques (MCMs). We mapped the minimal optimal epitope to a 10-mer peptide (SW10) in apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3C (APOBEC3) and determined the major histocompatibility complex class I restriction element as Mafa-A1*063, which is expressed in almost 90% of MCMs. APOBEC3C SW10-specific CD8+ T cells recognized immortalized B cells but not fibroblasts from a mHAg positive MCM. These results collectively provide a framework for identifying mHAgs in a nontransplant setting and suggest that APOBEC3C SW10 could be used as a lymphocyte-restricted model antigen in NHPs to test various mHAg-targeted immunotherapies. ImportanceCellular immunotherapies developed to treat blood cancers may also be effective against latent HIV. Preclinical studies of such immunotherapies are hindered by a lack of known target antigens. We used a combination of alloimmunization, basic immune assays, whole exome sequencing, and bioinformatics to identify a lymphocyte-restricted minor histocompatibility antigen in a genetically related population of nonhuman primates. This minor histocompatibility antigen provides an actionable target for piloting cellular immunotherapies designed to reduce or eliminate latent reservoirs of HIV.

immunology↗

bioRxiv2017

Pegivirus avoids immune recognition but does not attenuate acute-phase disease in a macaque model of HIV infection

Human pegivirus (HPgV) protects HIV+ people from HIV-associated disease, but the mechanism of this protective effect remains poorly understood. We sequentially infected cynomolgus macaques with simian pegivirus (SPgV) and simian immunodeficiency virus (SIV) to model HIV+HPgV co-infection. SPgV had no effect on acute-phase SIV pathogenesis - as measured by SIV viral load, CD4+ T cell destruction, and immune activation - suggesting that HPgVs protective effect is exerted primarily during the chronic phase of HIV infection. We also examined the immune response to SPgV in unprecedented detail, and found that this virus elicits virtually no activation of the immune system despite persistently high titers in the blood over long periods of time. Overall, this study expands our understanding of the pegiviruses - an understudied group of viruses with a high prevalence in the global human population - and suggests that the protective effect observed in HIV+HPgV co-infected people occurs primarily during the chronic phase of HIV infection.\n\nOne Sentence SummaryPegivirus avoids immune recognition but does not attenuate acute-phase disease in a macaque model of HIV infection.\n\nShort TitlePegivirus and AIDS-virus co-infection\n\nAccessible SummaryPeople infected with HIV live longer, healthier lives when they are co-infected with the human pegivirus (HPgV) - an understudied virus with a high prevalence in the global human population. To better understand how HPgV protects people with HIV from HIV-associated disease, we infected macaques with simian versions of these two viruses (SPgV and SIV). We found that SPgV had no impact on the incidence of SIV-associated disease early during the course of SIV infection - a time when SIV and HIV are known to cause irreversible damage to the immune system. Oddly, we found that the immune system did not recognize SPgV; a finding that warrants further investigation. Overall, this study greatly expands on our understanding of the pegiviruses and their interaction with the immune system.

immunology↗

bioRxiv2016

Improved full-length killer cell immunoglobulin-like receptor transcript discovery in Mauritian cynomolgus macaques

Killer cell Immunoglobulin-like Receptors (KIRs) modulate disease progression of pathogens including HIV, malaria, and hepatitis C. Cynomolgus and rhesus macaques are widely used as nonhuman primate models to study human pathogens and so considerable effort has been put into characterizing their KIR genetics. However, previous studies have relied on cDNA cloning and Sanger sequencing that lacks the throughput of current sequencing platforms. In this study, we present a high throughput, full-length allele discovery method utilizing PacBio circular consensus sequencing (CCS). We also describe a new approach to Macaque Exome Sequencing (MES) and the development of the Rhexome1.0, an adapted target capture reagent that includes macaque-specific capture probesets. By using sequence reads generated by whole genome sequencing (WGS) and MES to inform primer design, we were able to increase the sensitivity of KIR allele discovery. We demonstrate this increased sensitivity by defining nine novel alleles within a cohort of Mauritian cynomolgus macaques (MCM), a geographically isolated population with restricted KIR genetics that was thought to be completely characterized. Finally, we describe an approach to genotyping KIRs directly from sequence reads generated using WGS/MES reads. The findings presented here expand our understanding of KIR genetics in MCM by associating new genes with all eight KIR haplotypes and demonstrating the existence of at least one KIR3DS gene associated with every haplotype.

genetics↗