Selected Grantee Publications
Engineered IgM and IgG Cleaving Enzymes for Mitigating Antibody Neutralization and Complement Activation in AAV Gene Transfer
Smith et al., Molecular Therapy. 2024.
https://www.sciencedirect.com/science/article/pii/S1525001624003058?via%3Dihub=
Recombinant adeno-associated viral (AAV) vectors have emerged as the leading platform for therapeutic gene transfer, but systemic dosing of AAV vectors poses potential risk of adverse side effects, including complement activation triggered by anti-capsid immunity. In this study, investigators discovered an IgM cleaving enzyme (IceM) that degrades human IgM, a key trigger in the anti-AAV immune cascade. They engineered a fusion enzyme (IceMG) with dual proteolytic activity against human IgM and IgG. Antisera from animals treated with IceMG show decreased ability to neutralize AAV and activate complement. These studies have implications for improving the safety of AAV gene therapies and offer broader applications, including for organ transplantation and autoimmune diseases. Supported by ORIP (P51OD011107, U42OD027094), NHLBI, and NIAID.
Acquired Dysfunction of CFTR Underlies Cystic Fibrosis-Like Disease of the Canine Gallbladder
Gookin et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39041675/
Mucocele formation in dogs is pathologically similar to cystic fibrosis. In this study, researchers investigated the role of cystic fibrosis transmembrane conductance regulator (CFTR) in the pathogenesis of the disease. They determined the location and frequency of disease-associated variants in the coding region of CFTR using whole-genome sequence data from 2,642 dogs representing breeds at low risk, high risk, or with confirmed disease. The authors’ findings establish significant loss of CFTR-dependent anion secretion by mucocele gallbladder mucosa. There were no significant differences in CFTR gene variant frequency, type, or predicted impact comparing low-risk, high-risk, and definitively diagnosed groups of dogs. Their results suggest a disease of the canine gallbladder that is similar to cystic fibrosis and is driven by CFTR dysfunction. Supported by ORIP (T35OD011070, K01OD027058).
Time of Sample Collection Is Critical for the Replicability of Microbiome Analyses
Allaband et al., Nature Metabolism. 2024.
https://pubmed.ncbi.nlm.nih.gov/38951660/
Lack of replicability remains a challenge in microbiome studies. As the microbiome field moves from descriptive and associative research to mechanistic and interventional studies, being able to account for all confounding variables in the experimental design will be critical. Researchers conducted a retrospective analysis of 16S amplicon sequencing studies in male mice. They report that sample collection time affects the conclusions drawn from microbiome studies. The lack of consistency in the time of sample collection could help explain poor cross-study replicability in microbiome research. The effect of diurnal rhythms on the outcomes and study designs of other fields is unknown but is likely significant. Supported by ORIP (T32OD017863), NCATS, NCI, NHLBI, NIAAA, NIAID, NIBIB, NIDDK, and NIGMS.
Genetic Diversity of 1,845 Rhesus Macaques Improves Genetic Variation Interpretation and Identifies Disease Models
Wang et al., Nature Communications. 2024.
https://www.nature.com/articles/s41467-024-49922-6
Nonhuman primates are ideal models for certain human diseases, including retinal and neurodevelopmental disorders. Using a reverse genetics approach, researchers profiled the genetic diversity of rhesus macaque populations across eight primate research centers in the United States and uncovered rhesus macaques carrying naturally occurring pathogenic mutations. They identified more than 47,000 single-nucleotide variants in 374 genes that had been previously linked with retinal and neurodevelopmental disorders in humans. These newly identified variants can be used to study human disease pathology and to test novel treatments. Supported by ORIP (P51OD011107, P51OD011106, P40OD012217, S10OD032189), NEI, NIAID, and NIMH.
Natural Killer–Like B Cells Are a Distinct but Infrequent Innate Immune Cell Subset Modulated by SIV Infection of Rhesus Macaques
Manickam et al., PLOS Pathogens. 2024.
https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1012223
Natural killer–like B (NKB) cells express both natural killer (NK) and B cell receptors. Intracellular signaling proteins and trafficking markers were expressed differentially on naive NKB cells. CD20+ NKG2A/C+ NKB cells were identified in organs and lymph nodes of naive rhesus macaques (RMs). Single-cell RNA sequencing (scRNAseq) of sorted NKB cells confirmed that NKB cells are unique, and transcriptomic analysis of naive splenic NKB cells by scRNAseq showed that NKB cells undergo somatic hypermutation and express Ig receptors, similar to B cells. Expanded NKB frequencies were observed in RM gut and buccal mucosa after simian immunodeficiency virus (SIV) infection, and mucosal and peripheral NKB cells were associated with colorectal cytokine milieu and oral microbiome changes. NKB cells gated on CD3-CD14-CD20+NKG2A/C+ cells were inclusive of transcriptomically conventional B and NK cells in addition to true NKB cells, confounding accurate phenotyping and frequency recordings. Supported by ORIP (P51OD011132, S10OD026799) and NIAID.
Integrin αvβ3 Upregulation in Response to Nutrient Stress Promotes Lung Cancer Cell Metabolic Plasticity
Nam, Cancer Research. 2024.
https://pubmed.ncbi.nlm.nih.gov/38588407/
Tumor-initiating cells can survive in harsh environments via stress tolerance and metabolic flexibility; studies on this topic can yield new targets for cancer therapy. Using cultured cells and live human surgical biopsies of non-small cell lung cancer, researchers demonstrated that nutrient stress drives a metabolic reprogramming cascade that allows tumor cells to thrive despite a nutrient-limiting environment. This cascade results from upregulation of integrin αvβ3, a cancer stem cell marker. In mice, pharmacological or genetic targeting prevented lung cancer cells from evading the effects of nutrient stress, thus blocking tumor initiation. This work suggests that this molecular pathway leads to cancer stem cell reprogramming and could be linked to metabolic flexibility and tumor initiation. Supported by ORIP (K01OD030513), NCI, NIGMS, and NINDS.
Transcriptome- and Proteome-Wide Effects of a Circular RNA Encompassing Four Early Exons of the Spinal Muscular Atrophy Genes
Luo, Scientific Reports. 2024.
https://pubmed.ncbi.nlm.nih.gov/38714739/
Spinal muscular atrophy (SMA) is a leading genetic cause of mortality in infants and often results from a deficiency of deletions of or mutations in the SMN1 gene. In this study, researchers report the transcriptome- and proteome-wide effects of overexpression of C2A‑2B3-4, a circular RNA produced by SMN1 and SMN2, in cells. They report that C2A-2B-3-4 is associated with expression of genes associated with chromatin remodeling, transcription, spliceosome function, ribosome biogenesis, lipid metabolism, cytoskeletal formation, cell proliferation, and neuromuscular junction formation. More work is needed to investigate the role of these genes in processes associated with SMA and other pathological conditions, including cancer and male infertility. Supported by ORIP (T35OD027967) and NINDS.
CD8+ T Cell Targeting of Tumor Antigens Presented by HLA-E
Iyer, Science Advances. 2024.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11086602/
Researchers have hypothesized that human leukocyte antigen-E (HLA-E)–positive cancer cells could be targeted by HLA-E–restricted CD8+ T cells. In this study, the authors assessed whether major histocompatibility complex E (MHC-E) expression by cancer cells can be targeted for MHC-E–restricted T cell control. Using male rhesus macaques, they found that a cytomegalovirus can be used as a vector to generate specific immune cells that can target cancer cells. The authors conclude that targeting HLA-E with restricted, specific CD8+ T cells could offer a new approach for immunotherapy of prostate cancer. Overall, this study supports the concept of a cancer vaccine. Supported by ORIP (P51OD011092) and NIAID.
A Revamped Rat Reference Genome Improves the Discovery of Genetic Diversity in Laboratory Rats
de Jong, Cell Genomics. 2024.
https://www.cell.com/cell-genomics/fulltext/S2666-979X(24)00069-7
Rattus norvegicus has been used in many fields of study related to human disease; its genome was sequenced shortly after the genomes of Homo sapiens and Mus musculus. Investigators report extensive analyses of the improvements in mRatBN7.2, compared with the previous version. They conducted a broad analysis of a whole-genome sequencing data set of 163 samples from 120 inbred rat strains and substrains. Several additional resources have been created. This new assembly and its associated resources create a more solid platform for research on the many dimensions of physiology, behavior, and pathobiology of rats and can provide more reliable and meaningful translation of findings to human populations. Supported by ORIP (R24OD024617), NHGRI, NHLBI, and NIDA.
Potent HPIV3-Neutralizing IGHV5-51 Antibodies Identified from Multiple Individuals Show L Chain and CDRH3 Promiscuity
Abu-Shmais et al., Journal of Immunology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38488511/
Human parainfluenza virus 3 fusion glycoprotein (HPIV3 F), responsible for facilitating viral entry into host cells, is a major target of neutralizing antibodies that inhibit infection. More work is needed to understand these dynamics. Researchers characterized the genetic signatures, epitope specificity, neutralization potential, and publicness of HPIV3-specific antibodies identified across multiple individuals. From this work, they identified 12 potently neutralizing antibodies targeting three nonoverlapping epitopes on HPIV3 F. Six of the antibodies used immunoglobulin heavy variable gene, IGHV 5-51. These antibodies used different L chain variable genes (VL) and diverse H chain CDR 3 (CDRH3) sequences. These findings help elucidate the genetic and functional characteristics of HPIV3-neutralizing antibodies and indicate the existence of a reproducible H chain variable–dependent antibody response associated with VL and CDRH3 promiscuity. Supported by ORIP (K01OD036063), NCATS, NCI, NEI, NIAID, and NIDDK.