Biology subjects

Li, H. W.

Publications and source records attributed to Li, H. W..

4 recordsLinked to original sources

bioRxiv2026

A novel model demonstrating that human immune cells promote multiorgan SARS-CoV-2 dissemination and human T cells limit anti-viral innate immunity

Despite extensive studies, many questions remain regarding the pathology and mechanisms behind Coronavirus disease 2019 (COVID-19), and particularly on post-acute sequelae of COVID-19 (PASC). Because existing mouse models cannot recapitulate human immune responses, we developed a human immune system (HIS) mouse model with physiologic expression of hACE2. After intranasal infection, persistent viral RNA was observed in multiple organs for 8 weeks, despite the generation of human SARS-CoV-2-specific T cell responses. Human immune cells increased viral infection in the lung and non-pulmonary tissues. COVID-19-related pathology was recapitulated in the lungs, with fibrosis peaking at 14 days post-infection. Immune activation was detected in the lungs, hearts, intestines and brains of acutely infected mice and persisted at 8 weeks in the heart and lungs. The presence of human T cells correlated with attenuated innate antiviral transcriptional signatures in the lung, where a persisting cytotoxic mature CD4+ T cell population with JAK-STAT activation was enriched in infected mice. Thus, human T cells mount an antigen-specific but ultimately dysfunctional response, while paradoxically suppressing the innate interferon response, permitting chronic interferon activation and long-term viral persistence, recapitulating several immunologic and histopathologic features associated with PASC. This model will uniquely facilitate understanding of virus-human immune dynamics and therapeutic approaches to PASC.

immunology↗

bioRxiv2026

A universal platform for simultaneous TCRα/β removal enables safer and more potent TCR therapies and autoimmune modeling

Adoptive T-cell therapies using tumour-specific T-cell receptors (TCRs) are limited by competition with endogenous receptors, which impairs efficacy and poses risks of off-target autoreactivity. Here we present a CRISPR-based platform that completely and selectively eliminates both endogenous TCR- and -{beta} chains without affecting introduced transgenic TCRs, irrespective of codon optimization. This approach achieves >90% deletion efficiency in Jurkat and primary human T cells, markedly enhancing the expression, pairing fidelity, and functional potency of transgenic receptors. Using a clinically relevant HLA-A*02:01-restricted DMF5 TCR, we show that dual TCR ablation boosts antigen-specific activation and cytotoxicity in vitro and significantly enhances tumor clearance in vivo in human immune system (HIS) mice, while preventing graft-versus-host disease (GVHD). Targeted locus amplification revealed that CRISPR-induced double-strand breaks did not alter lentiviral integration profiles, confirming genomic safety. Extending this approach to four insulin-reactive TCRs demonstrated that removal of endogenous receptors increased transduction efficiency and functional activity, with one (1E6) showing selective activation and infiltration of stem cell-derived islet grafts (SC-islets) in vivo. This study establishes a universal, safe, and scalable genome-editing platform for generating functionally precise human T cells. By integrating cancer immunotherapy and autoimmune disease modelling within a single framework, it provides a strong preclinical rationale for dual endogenous TCR removal as a route to improved specificity, safety, and therapeutic efficacy in TCR-based cell therapies.

immunology↗

bioRxiv2024

Follicular helper- and peripheral helper-like T cells drive autoimmune disease in human immune system mice

Human immune system (HIS) mice constructed in various ways are widely used for investigations of human immune responses to pathogens, transplants and immunotherapies. In HIS mice that generate T cells de novo from hematopoietic progenitors, T cell-dependent multisystem autoimmune disease occurs, most rapidly when the human T cells develop in the native NOD.Cg- Prkdcscid Il2rgtm1Wjl (NSG) mouse thymus, where negative selection is abnormal. Disease develops very late when human T cells develop in human fetal thymus grafts, where robust negative selection is observed. We demonstrate here that PD-1+CD4+ peripheral (Tph) helper-like and follicular (Tfh) helper-like T cells developing in HIS mice can induce autoimmune disease. Tfh- like cells were more prominent in HIS mice with a mouse thymus, in which the highest levels of IgG were detected in plasma, compared to those with a human thymus. While circulating IgG and IgM antibodies were autoreactive to multiple mouse antigens, in vivo depletion of B cells and antibodies did not delay the development of autoimmune disease. Conversely, adoptive transfer of enriched Tfh- or Tph-like cells induced disease and autoimmunity-associated B cell phenotypes in recipient mice containing autologous human APCs without T cells. Tfh/Tph cells from mice with a human thymus expanded and induced disease more rapidly than those originating in a murine thymus, implicating HLA-restricted T cell-APC interactions in this process. Since Tfh, Tph, autoantibodies and lymphopenia-induced proliferation (LIP) have all been implicated in various forms of human autoimmune disease, the observations here provide a platform for the further dissection of human autoimmune disease mechanisms and therapies.

immunology↗

bioRxiv2021

Interleukin-15 Receptor α Chain Knockout NOD-SCID mice have reduced numbers of NK cells, develop thymic lymphomas and fail to engraft human hematopoietic cells

NOD-SCID IL2r{gamma}cnull (NSG) mice are widely used to model human immune cell development because they are more permissive for human hematopoietic cell engraftment and reconstitution than NOD-SCID mice. While increased human reconstitution in the blood of NSG mice has been attributed to the absence of mouse NK cells, deletion of the common gamma chain ({gamma}c) limits development of lymphoid tissue inducer cells and precludes development of normal secondary lymphoid structures. The disorganized lymphoid tissue leads to compromised human T cell-B cell interactions and results in variable human immune cell function in human immune system (HIS) NSG compared to NOD-SCID mice. We attempted to remove mouse NK cells from NOD-SCID mice while retaining other {gamma}c-dependent cytokine responses by targeted disruption of the mouse genomic IL15RA locus with CRISPR/Cas9. IL15R is required for the development, function and survival of NK cells. NOD-SCID IL15R-/- mice showed reductions in NK cells and NK cell function. However, NOD-SCID IL15R-/- mice demonstrated accelerated thymic lymphomagenesis and showed earlier mortality compared to NOD-SCID mice. This result suggests that mouse NK cells are important to delay lymphoma development in NOD-SCID mice. We transplanted thymectomized NOD-SCID ILl5R-/- mice with human fetal liver CD34+ cells and thymus to determine if these mice supported engraftment and development of a transplanted HIS. Surprisingly, we found that peripheral human engraftment was inferior (mean 0.05% of lymphocytes) to that in both NOD-SCID (mean, 10.5% of lymphocytes) and NSG (mean, 54% of lymphocytes) mice. These results indicate that NOD-SCID IL15R-/- mice are not permissive for human CD34+ cell engraftment.

immunology↗