RESUMEN
The choice of developing thymocytes to become CD8+ cytotoxic or CD4+ helper T cells has been intensely studied, but many of the underlying mechanisms remain to be elucidated. Recent multiomics approaches have provided much higher resolution analysis of gene expression in developing thymocytes than was previously achievable, thereby offering a fresh perspective on this question. Focusing on our recent studies using CITE-seq (cellular indexing of transcriptomes and epitopes) analyses of mouse thymocytes, we present a detailed timeline of RNA and protein expression changes during CD8 versus CD4 T cell differentiation. We also revisit our current understanding of the links between T cell receptor signaling and expression of the lineage-defining transcription factors ThPOK and RUNX3. Finally, we propose a sequential selection model to explain the tight linkage between MHC-I versus MHC-II recognition and T cell lineage choice. This model incorporates key aspects of previously proposed kinetic signaling, instructive, and stochastic/selection models.
Asunto(s)
Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Diferenciación Celular , Linaje de la Célula , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Humanos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Ratones , Factores de Transcripción/metabolismo , Transcriptoma , MultiómicaRESUMEN
Regionalized immune surveillance relies on the concerted efforts of diverse memory T cell populations. Of these, tissue-resident memory T (TRM) cells are strategically positioned in barrier tissues, where they enable efficient frontline defense against infections and cancer. However, the long-term persistence of these cells has been implicated in a variety of immune-mediated pathologies. Consequently, modulating TRM cell populations represents an attractive strategy for novel vaccination and therapeutic interventions against tissue-based diseases. Here, we provide an updated overview of TRM cell heterogeneity and function across tissues and disease states. We discuss mechanisms of TRM cell-mediated immune protection and their potential contributions to autoimmune disorders. Finally, we examine how TRM cell responses might be durably boosted or dampened for therapeutic gain.
Asunto(s)
Memoria Inmunológica , Células T de Memoria , Humanos , Animales , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Especificidad de Órganos/inmunología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Vigilancia InmunológicaRESUMEN
The evolution of IgE in mammals added an extra layer of immune protection at body surfaces to provide a rapid and local response against antigens from the environment. The IgE immune response employs potent expulsive and inflammatory forces against local antigen provocation, at the risk of damaging host tissues and causing allergic disease. Two well-known IgE receptors, the high-affinity FcεRI and low-affinity CD23, mediate the activities of IgE. Unlike other known antibody receptors, CD23 also regulates IgE expression, maintaining IgE homeostasis. This mechanism evolved by adapting the function of the complement receptor CD21. Recent insights into the dynamic character of IgE structure, its resultant capacity for allosteric modulation, and the potential for ligand-induced dissociation have revealed previously unappreciated mechanisms for regulation of IgE and IgE complexes. We describe recent research, highlighting structural studies of the IgE network of proteins to analyze the uniquely versatile activities of IgE and anti-IgE biologics.
Asunto(s)
Productos Biológicos , Receptores de IgE , Humanos , Animales , Receptores de IgE/química , Receptores de IgE/metabolismo , Inmunoglobulina E/metabolismo , Receptores Fc , Mamíferos/metabolismoRESUMEN
Transforming growth factor ß (TGF-ß) is a key cytokine regulating the development, activation, proliferation, differentiation, and death of T cells. In CD4+ T cells, TGF-ß maintains the quiescence and controls the activation of naive T cells. While inhibiting the differentiation and function of Th1 and Th2 cells, TGF-ß promotes the differentiation of Th17 and Th9 cells. TGF-ß is required for the induction of Foxp3 in naive T cells and the development of regulatory T cells. TGF-ß is crucial in the differentiation of tissue-resident memory CD8+ T cells and their retention in the tissue, whereas it suppresses effector T cell function. In addition, TGF-ß also regulates the generation or function of natural killer T cells, γδ T cells, innate lymphoid cells, and gut intraepithelial lymphocytes. Here I highlight the major findings and recent advances in our understanding of TGF-ß regulation of T cells and provide a personal perspective of the field.
Asunto(s)
Linfocitos T CD8-positivos , Factor de Crecimiento Transformador beta1 , Animales , Humanos , Diferenciación Celular , Inmunidad Innata , Linfocitos/metabolismo , Linfocitos T Reguladores/metabolismo , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
Sialic acid-binding immunoglobulin-type lectins (Siglecs) are expressed on the majority of white blood cells of the immune system and play critical roles in immune cell signaling. Through recognition of sialic acid-containing glycans as ligands, they help the immune system distinguish between self and nonself. Because of their restricted cell type expression and roles as checkpoints in immune cell responses in human diseases such as cancer, asthma, allergy, neurodegeneration, and autoimmune diseases they have gained attention as targets for therapeutic interventions. In this review we describe the Siglec family, its roles in regulation of immune cell signaling, current efforts to define its roles in disease processes, and approaches to target Siglecs for treatment of human disease.
Asunto(s)
Susceptibilidad a Enfermedades , Proteínas de Punto de Control Inmunitario/genética , Proteínas de Punto de Control Inmunitario/metabolismo , Inmunomodulación , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/genética , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/metabolismo , Transducción de Señal , Animales , Biomarcadores , Humanos , Sistema Inmunológico/inmunología , Sistema Inmunológico/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismoRESUMEN
Neonatal CD4+ and CD8+ T cells have historically been characterized as immature or defective. However, recent studies prompt a reinterpretation of the functions of neonatal T cells. Rather than a population of cells always falling short of expectations set by their adult counterparts, neonatal T cells are gaining recognition as a distinct population of lymphocytes well suited for the rapidly changing environment in early life. In this review, I will highlight new evidence indicating that neonatal T cells are not inert or less potent versions of adult T cells but instead are a broadly reactive layer of T cells poised to quickly develop into regulatory or effector cells, depending on the needs of the host. In this way, neonatal T cells are well adapted to provide fast-acting immune protection against foreign pathogens, while also sustaining tolerance to self-antigens.
Asunto(s)
Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Inmunidad Adaptativa , Animales , Biomarcadores , Diferenciación Celular/inmunología , Interacciones Huésped-Patógeno , Humanos , Memoria Inmunológica , Activación de Linfocitos/inmunología , Células Progenitoras Linfoides/citología , Células Progenitoras Linfoides/inmunología , Células Progenitoras Linfoides/metabolismo , Fenotipo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Subgrupos de Linfocitos T/citologíaRESUMEN
The discovery of CD4+ T cell subset-defining master transcription factors and framing of the Th1/Th2 paradigm ignited the CD4+ T cell field. Advances in in vivo experimental systems, however, have revealed that more complex lineage-defining transcriptional networks direct CD4+ T cell differentiation in the lymphoid organs and tissues. This review focuses on the layers of fate decisions that inform CD4+ T cell differentiation in vivo. Cytokine production by antigen-presenting cells and other innate cells influences the CD4+ T cell effector program [e.g., T helper type 1 (Th1), Th2, Th17]. Signals downstream of the T cell receptor influence whether individual clones bearing hallmarks of this effector program become T follicular helper cells, supporting development of B cells expressing specific antibody isotypes, or T effector cells, which activate microbicidal innate cells in tissues. These bifurcated, parallel axes allow CD4+ T cells to augment their particular effector program and prevent disease.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Diferenciación Celular/inmunología , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos/citología , Diferenciación Celular/genética , Citocinas/metabolismo , Humanos , Activación de Linfocitos/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/inmunología , Células Th2/metabolismoRESUMEN
The intestinal microbiota plays a crucial role in influencing the development of host immunity, and in turn the immune system also acts to regulate the microbiota through intestinal barrier maintenance and immune exclusion. Normally, these interactions are homeostatic, tightly controlled, and organized by both innate and adaptive immune responses. However, a combination of environmental exposures and genetic defects can result in a break in tolerance and intestinal homeostasis. The outcomes of these interactions at the mucosal interface have broad, systemic effects on host immunity and the development of chronic inflammatory or autoimmune disease. The underlying mechanisms and pathways the microbiota can utilize to regulate these diseases are just starting to emerge. Here, we discuss the recent evidence in this area describing the impact of microbiota-immune interactions during inflammation and autoimmunity, with a focus on barrier function and CD4+ T cell regulation.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Diabetes Mellitus Tipo 1/microbiología , Microbioma Gastrointestinal/inmunología , Inflamación/microbiología , Enfermedades Inflamatorias del Intestino/microbiología , Mucosa Intestinal/microbiología , Animales , Autoinmunidad , Diabetes Mellitus Tipo 1/inmunología , Homeostasis , Humanos , Tolerancia Inmunológica , Inmunomodulación , Inflamación/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Mucosa Intestinal/inmunologíaRESUMEN
The complement system is an evolutionarily ancient key component of innate immunity required for the detection and removal of invading pathogens. It was discovered more than 100 years ago and was originally defined as a liver-derived, blood-circulating sentinel system that classically mediates the opsonization and lytic killing of dangerous microbes and the initiation of the general inflammatory reaction. More recently, complement has also emerged as a critical player in adaptive immunity via its ability to instruct both B and T cell responses. In particular, work on the impact of complement on T cell responses led to the surprising discoveries that the complement system also functions within cells and is involved in regulating basic cellular processes, predominantly those of metabolic nature. Here, we review current knowledge about complement's role in T cell biology, with a focus on the novel intracellular and noncanonical activities of this ancient system.
Asunto(s)
Proteínas del Sistema Complemento/inmunología , Inmunomodulación , Linfocitos T/inmunología , Linfocitos T/metabolismo , Inmunidad Adaptativa , Animales , Autoinmunidad , Linfocitos B/inmunología , Linfocitos B/metabolismo , Activación de Complemento/inmunología , Metabolismo Energético , Interacciones Huésped-Patógeno/inmunología , Humanos , Inmunidad Celular , Proteína Cofactora de Membrana/metabolismo , Células TH1/inmunología , Células TH1/metabolismoRESUMEN
T cell receptors (TCRs) are protein complexes formed by six different polypeptides. In most T cells, TCRs are composed of αß subunits displaying immunoglobulin-like variable domains that recognize peptide antigens associated with major histocompatibility complex molecules expressed on the surface of antigen-presenting cells. TCRαß subunits are associated with the CD3 complex formed by the γ, δ, ε, and ζ subunits, which are invariable and ensure signal transduction. Here, we review how the expression and function of TCR complexes are orchestrated by several fine-tuned cellular processes that encompass (a) synthesis of the subunits and their correct assembly and expression at the plasma membrane as a single functional complex, (b) TCR membrane localization and dynamics at the plasma membrane and in endosomal compartments, (c) TCR signal transduction leading to T cell activation, and (d) TCR degradation. These processes balance each other to ensure efficient T cell responses to a variety of antigenic stimuli while preventing autoimmunity.
Asunto(s)
Regulación de la Expresión Génica , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Linfocitos T/inmunología , Linfocitos T/metabolismo , Animales , Biomarcadores , Complejo CD3/genética , Complejo CD3/metabolismo , Membrana Celular/metabolismo , Endocitosis/genética , Endocitosis/inmunología , Endosomas/metabolismo , Humanos , Inmunomodulación , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Proteolisis , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/genética , Relación Estructura-ActividadRESUMEN
To monitor the health of cells, the immune system tasks antigen-presenting cells with gathering antigens from other cells and bringing them to CD8 T cells in the form of peptides bound to MHC-I molecules. Most cells would be unable to perform this function because they use their MHC-I molecules to exclusively present peptides derived from the cell's own proteins. However, the immune system evolved mechanisms for dendritic cells and some other phagocytes to sample and present antigens from the extracellular milieu on MHC-I through a process called cross-presentation. How this important task is accomplished, its role in health and disease, and its potential for exploitation are the subject of this review.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Reactividad Cruzada , Células Dendríticas/inmunología , Animales , Antígenos/inmunología , Antígenos/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Vigilancia Inmunológica , Activación de Linfocitos , FagocitosisRESUMEN
Allogeneic chimeric antigen receptor (CAR)-T cells hold great promise for expanding the accessibility of CAR-T therapy, whereas the risks of allograft rejection have hampered its application. Here, we genetically engineered healthy-donor-derived, CD19-targeting CAR-T cells using CRISPR-Cas9 to address the issue of immune rejection and treated one patient with refractory immune-mediated necrotizing myopathy and two patients with diffuse cutaneous systemic sclerosis with these cells. This study was registered at ClinicalTrials.gov (NCT05859997). The infused cells persisted for over 3 months, achieving complete B cell depletion within 2 weeks of treatment. During the 6-month follow-up, we observed deep remission without cytokine release syndrome or other serious adverse events in all three patients, primarily shown by the significant improvement in the clinical response index scores for the two diseases, respectively, and supported by the observations of reversal of inflammation and fibrosis. Our results demonstrate the high safety and promising immune modulatory effect of the off-the-shelf CAR-T cells in treating severe refractory autoimmune diseases.
Asunto(s)
Antígenos CD19 , Inmunoterapia Adoptiva , Miositis , Receptores Quiméricos de Antígenos , Esclerodermia Sistémica , Humanos , Antígenos CD19/inmunología , Antígenos CD19/metabolismo , Miositis/terapia , Miositis/inmunología , Esclerodermia Sistémica/terapia , Esclerodermia Sistémica/inmunología , Inmunoterapia Adoptiva/métodos , Femenino , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/metabolismo , Masculino , Persona de Mediana Edad , Adulto , Linfocitos T/inmunología , Linfocitos T/metabolismo , Trasplante HomólogoRESUMEN
Cancer immunotherapy has transformed treatment possibilities, but its effectiveness differs significantly among patients, indicating the presence of alternative pathways for immune evasion. Here, we show that ITPRIPL1 functions as an inhibitory ligand of CD3ε, and its expression inhibits T cells in the tumor microenvironment. The binding of ITPRIPL1 extracellular domain to CD3ε on T cells significantly decreased calcium influx and ZAP70 phosphorylation, impeding initial T cell activation. Treatment with a neutralizing antibody against ITPRIPL1 restrained tumor growth and promoted T cell infiltration in mouse models across various solid tumor types. The antibody targeting canine ITPRIPL1 exhibited notable therapeutic efficacy against naturally occurring tumors in pet clinics. These findings highlight the role of ITPRIPL1 (or CD3L1, CD3ε ligand 1) in impeding T cell activation during the critical "signal one" phase. This discovery positions ITPRIPL1 as a promising therapeutic target against multiple tumor types.
Asunto(s)
Complejo CD3 , Activación de Linfocitos , Linfocitos T , Escape del Tumor , Microambiente Tumoral , Animales , Complejo CD3/metabolismo , Complejo CD3/inmunología , Humanos , Ratones , Linfocitos T/inmunología , Linfocitos T/metabolismo , Microambiente Tumoral/inmunología , Perros , Neoplasias/inmunología , Línea Celular Tumoral , Femenino , Unión Proteica , Proteína Tirosina Quinasa ZAP-70/metabolismo , Anticuerpos Neutralizantes/inmunología , Ratones Endogámicos C57BLRESUMEN
The CD4-binding site (CD4bs) is a conserved epitope on HIV-1 envelope (Env) that can be targeted by protective broadly neutralizing antibodies (bnAbs). HIV-1 vaccines have not elicited CD4bs bnAbs for many reasons, including the occlusion of CD4bs by glycans, expansion of appropriate naive B cells with immunogens, and selection of functional antibody mutations. Here, we demonstrate that immunization of macaques with a CD4bs-targeting immunogen elicits neutralizing bnAb precursors with structural and genetic features of CD4-mimicking bnAbs. Structures of the CD4bs nAb bound to HIV-1 Env demonstrated binding angles and heavy-chain interactions characteristic of all known human CD4-mimicking bnAbs. Macaque nAb were derived from variable and joining gene segments orthologous to the genes of human VH1-46-class bnAb. This vaccine study initiated in primates the B cells from which CD4bs bnAbs can derive, accomplishing the key first step in the development of an effective HIV-1 vaccine.
Asunto(s)
Vacunas contra el SIDA , VIH-1 , Animales , Humanos , Anticuerpos ampliamente neutralizantes , Antígenos CD4 , Moléculas de Adhesión Celular , VIH-1/fisiología , Macaca , Vacunas contra el SIDA/inmunologíaRESUMEN
Exhausted CD8 T (Tex) cells in chronic viral infection and cancer have sustained co-expression of inhibitory receptors (IRs). Tex cells can be reinvigorated by blocking IRs, such as PD-1, but synergistic reinvigoration and enhanced disease control can be achieved by co-targeting multiple IRs including PD-1 and LAG-3. To dissect the molecular changes intrinsic when these IR pathways are disrupted, we investigated the impact of loss of PD-1 and/or LAG-3 on Tex cells during chronic infection. These analyses revealed distinct roles of PD-1 and LAG-3 in regulating Tex cell proliferation and effector functions, respectively. Moreover, these studies identified an essential role for LAG-3 in sustaining TOX and Tex cell durability as well as a LAG-3-dependent circuit that generated a CD94/NKG2+ subset of Tex cells with enhanced cytotoxicity mediated by recognition of the stress ligand Qa-1b, with similar observations in humans. These analyses disentangle the non-redundant mechanisms of PD-1 and LAG-3 and their synergy in regulating Tex cells.
Asunto(s)
Antígenos CD , Linfocitos T CD8-positivos , Antígenos de Histocompatibilidad Clase I , Proteína del Gen 3 de Activación de Linfocitos , Subfamília D de Receptores Similares a Lectina de las Células NK , Receptor de Muerte Celular Programada 1 , Animales , Antígenos CD/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Ratones , Receptor de Muerte Celular Programada 1/metabolismo , Subfamília D de Receptores Similares a Lectina de las Células NK/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Subfamília C de Receptores Similares a Lectina de Células NK/metabolismo , Ratones Endogámicos C57BL , Proteínas del Grupo de Alta Movilidad/metabolismo , Proteínas del Grupo de Alta Movilidad/genética , Citotoxicidad Inmunológica , Proliferación Celular , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/inmunologíaRESUMEN
Reversing CD8+ T cell dysfunction is crucial in treating chronic hepatitis B virus (HBV) infection, yet specific molecular targets remain unclear. Our study analyzed co-signaling receptors during hepatocellular priming and traced the trajectory and fate of dysfunctional HBV-specific CD8+ T cells. Early on, these cells upregulate PD-1, CTLA-4, LAG-3, OX40, 4-1BB, and ICOS. While blocking co-inhibitory receptors had minimal effect, activating 4-1BB and OX40 converted them into antiviral effectors. Prolonged stimulation led to a self-renewing, long-lived, heterogeneous population with a unique transcriptional profile. This includes dysfunctional progenitor/stem-like (TSL) cells and two distinct dysfunctional tissue-resident memory (TRM) populations. While 4-1BB expression is ubiquitously maintained, OX40 expression is limited to TSL. In chronic settings, only 4-1BB stimulation conferred antiviral activity. In HBeAg+ chronic patients, 4-1BB activation showed the highest potential to rejuvenate dysfunctional CD8+ T cells. Targeting all dysfunctional T cells, rather than only stem-like precursors, holds promise for treating chronic HBV infection.
Asunto(s)
Linfocitos T CD8-positivos , Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Hepatitis B Crónica/metabolismo , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Transducción de Señal , Animales , Receptores OX40/metabolismo , Ratones , Receptor de Muerte Celular Programada 1/metabolismo , Antígenos CD/metabolismoRESUMEN
Latent membrane protein 1 (LMP1) is the primary oncoprotein of Epstein-Barr virus (EBV) and plays versatile roles in the EBV life cycle and pathogenesis. Despite decades of extensive research, the molecular basis for LMP1 folding, assembly, and activation remains unclear. Here, we report cryo-electron microscopy structures of LMP1 in two unexpected assemblies: a symmetric homodimer and a higher-order filamentous oligomer. LMP1 adopts a non-canonical and unpredicted fold that supports the formation of a stable homodimer through tight and antiparallel intermolecular packing. LMP1 dimers further assemble side-by-side into higher-order filamentous oligomers, thereby allowing the accumulation and specific organization of the flexible cytoplasmic tails for efficient recruitment of downstream factors. Super-resolution microscopy and cellular functional assays demonstrate that mutations at both dimeric and oligomeric interfaces disrupt LMP1 higher-order assembly and block multiple LMP1-mediated signaling pathways. Our research provides a framework for understanding the mechanism of LMP1 and for developing potential therapies targeting EBV-associated diseases.
Asunto(s)
Microscopía por Crioelectrón , Herpesvirus Humano 4 , Multimerización de Proteína , Proteínas de la Matriz Viral , Proteínas de la Matriz Viral/metabolismo , Proteínas de la Matriz Viral/química , Proteínas de la Matriz Viral/genética , Humanos , Herpesvirus Humano 4/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiología , Modelos Moleculares , Células HEK293 , Transducción de Señal , Infecciones por Virus de Epstein-Barr/virología , Infecciones por Virus de Epstein-Barr/metabolismo , MutaciónRESUMEN
While CD4+ T cell depletion is key to disease progression in people living with HIV and SIV-infected macaques, the mechanisms underlying this depletion remain incompletely understood, with most cell death involving uninfected cells. In contrast, SIV infection of "natural" hosts such as sooty mangabeys does not cause CD4+ depletion and AIDS despite high-level viremia. Here, we report that the CARD8 inflammasome is activated immediately after HIV entry by the viral protease encapsulated in incoming virions. Sensing of HIV protease activity by CARD8 leads to rapid pyroptosis of quiescent cells without productive infection, while T cell activation abolishes CARD8 function and increases permissiveness to infection. In humanized mice reconstituted with CARD8-deficient cells, CD4+ depletion is delayed despite high viremia. Finally, we discovered loss-of-function mutations in CARD8 from "natural hosts," which may explain the peculiarly non-pathogenic nature of these infections. Our study suggests that CARD8 drives CD4+ T cell depletion during pathogenic HIV/SIV infections.
Asunto(s)
Infecciones por VIH , Inflamasomas , Síndrome de Inmunodeficiencia Adquirida del Simio , Animales , Humanos , Ratones , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Progresión de la Enfermedad , Infecciones por VIH/patología , Inflamasomas/metabolismo , Proteínas de Neoplasias/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Virus de la Inmunodeficiencia de los Simios/fisiología , Viremia , VIH/fisiologíaRESUMEN
Overcoming immune-mediated resistance to PD-1 blockade remains a major clinical challenge. Enhanced efficacy has been demonstrated in melanoma patients with combined nivolumab (anti-PD-1) and relatlimab (anti-LAG-3) treatment, the first in its class to be FDA approved. However, how these two inhibitory receptors synergize to hinder anti-tumor immunity remains unknown. Here, we show that CD8+ T cells deficient in both PD-1 and LAG-3, in contrast to CD8+ T cells lacking either receptor, mediate enhanced tumor clearance and long-term survival in mouse models of melanoma. PD-1- and LAG-3-deficient CD8+ T cells were transcriptionally distinct, with broad TCR clonality and enrichment of effector-like and interferon-responsive genes, resulting in enhanced IFN-γ release indicative of functionality. LAG-3 and PD-1 combined to drive T cell exhaustion, playing a dominant role in modulating TOX expression. Mechanistically, autocrine, cell-intrinsic IFN-γ signaling was required for PD-1- and LAG-3-deficient CD8+ T cells to enhance anti-tumor immunity, providing insight into how combinatorial targeting of LAG-3 and PD-1 enhances efficacy.
Asunto(s)
Antígenos CD , Linfocitos T CD8-positivos , Interferón gamma , Proteína del Gen 3 de Activación de Linfocitos , Ratones Endogámicos C57BL , Receptor de Muerte Celular Programada 1 , Receptor de Muerte Celular Programada 1/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Animales , Interferón gamma/metabolismo , Ratones , Antígenos CD/metabolismo , Comunicación Autocrina , Humanos , Melanoma/inmunología , Melanoma/tratamiento farmacológico , Femenino , Línea Celular Tumoral , Melanoma Experimental/inmunología , Agotamiento de Células TRESUMEN
Relatlimab (rela; anti-LAG-3) plus nivolumab (nivo; anti-PD-1) is safe and effective for treatment of advanced melanoma. We designed a trial (NCT03743766) where advanced melanoma patients received rela, nivo, or rela+nivo to interrogate the immunologic mechanisms of rela+nivo. Analysis of biospecimens from this ongoing trial demonstrated that rela+nivo led to enhanced capacity for CD8+ T cell receptor signaling and altered CD8+ T cell differentiation, leading to heightened cytotoxicity despite the retention of an exhaustion profile. Co-expression of cytotoxic and exhaustion signatures was driven by PRDM1, BATF, ETV7, and TOX. Effector function was upregulated in clonally expanded CD8+ T cells that emerged after rela+nivo. A rela+nivo intratumoral CD8+ T cell signature was associated with a favorable prognosis. This intratumoral rela+nivo signature was validated in peripheral blood as an elevated frequency of CD38+TIM3+CD8+ T cells. Overall, we demonstrated that cytotoxicity can be enhanced despite the retention of exhaustion signatures, which will inform future therapeutic strategies.