Immunology
Abstract
Authors
Peter Dimitrion, Jesse Veenstra, Deangelo Ferguson, Ping Wang, Jeffrey Cruz, Tasneem F. Mohammad, Ian Loveless, Aamir Siddiqui, Iltefat H. Hamzavi, Li Zhou, Indra Adrianto, Qing-Sheng Mi
Abstract
Antiviral immunity profoundly impacts host metabolism, which can, in turn, modulate immune responses and influence disease pathology. The liver orchestrates systemic bile acid (BA) metabolism, a pathway disrupted in chronic liver diseases such as viral hepatitis. BAs are increasingly recognized for their immunomodulatory properties. Thus, improved understanding of the interplay between immunity and BA metabolism may reveal novel therapeutic avenues. Using lymphocytic choriomeningitis virus (LCMV) as a model, we investigated the interplay between chronic virus infection, BA metabolism, and immunity. Chronic LCMV infection increased BA levels and shifted circulating and liver BA composition toward host-derived, conjugated BAs. Hepatic BA transport and synthesis genes were broadly downregulated, in part depending on CD8+ T cells. Pharmacological inhibition of the main hepatic transporter of conjugated BAs, NTCP (Slc10a1), increased hepatic damage, while combined genetic disruption of the BA transporters Slco1a1, Slco1a4, and Slco1b2, responsible for the hepatic reuptake of unconjugated BA, reduced liver pathology and impaired antiviral CD8+ T cell responses. These findings reveal a reciprocal interplay between BA metabolism and CD8+ T cells, expanding our understanding of adaptive immunity in viral hepatitis. They also highlight how immunometabolic changes in liver disease may affect adaptive immune responses against infections.
Authors
Felix Clemens Richter, Zsofia Keszei, Csilla Viczenczova, Maximilian Baumgartner, Henrique G. Colaço, Magdalena Siller, Lisa Holnsteiner, Hatoon Baazim, Anna Hofmann, Aubrey Burrett, Anna Schönbichler, Lukas Endler, Joel Xu En Wong, Laura Antonio-Herrera, Oleksandr Petrenko, Fabian Amman, Jakob-Wendelin Genger, Claudia D. Fuchs, Hubert Scharnagl, Hanns-Ulrich Marschall, Thomas Reiberger, Karl S. Lang, Clarissa Campbell, Michael Trauner, Andreas Bergthaler
Abstract
Recent evidence suggests a role for biological factors to explain increased risk for active pulmonary tuberculosis (PTB) among men. We conducted a prospective cohort study in Mali of treatment naive males and females with laboratory-confirmed PTB and latent TB infection (LTBI) and healthy controls of similar ages to determine the relationship between alterations in gonadal steroids, tuberculosis (TB) disease status, and treatment outcomes. Prior to treatment, males with PTB had lower testosterone concentrations compared to males with LTBI or healthy males. Reduced testosterone concentrations in males with PTB were transient, returning healthy ranges by month 2 of treatment, which corresponded to the end of intensive TB treatment. Estradiol concentrations in females were not altered by PTB or infection status yet increased at month 6 of treatment. Testosterone, but not estradiol, was a strong predictor of cure during treatment. Testosterone, but not estradiol, concentrations in PTB cases were inversely correlated with IFN-γ, IL-6, and IL-2. Concentrations of IL-17 and IL-10 were lower in males than females at the end of TB treatment. Our results suggest that TB-induced changes in testosterone concentrations during PTB and in response to treatment occur in males and could contribute to sex differences in TB pathogenesis.
Authors
Djeneba Dabitao, Bocar Baya, Ibrahim Sanogo, Amadou Somboro, Mamadou Wague, Mamadou D. Coulibaly, Isaac Koloma, Mahamadou Kone, Mohamed Nantoume, Nadie Coulibaly, Behinan Stephane, Mariam Coulibaly, Mamadou Perou, Moumine Sanogo, Ayouba Diarra, Seydou Samake, Bassirou Diarra, Mahamadou Diakite, Souleymane Diallo, Yacouba Toloba, Chad J. Achenbach, Jane L. Holl, Seydou Doumbia, Robert L. Murphy, William R. Bishai, Sabra L. Klein
Abstract
Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn’s disease (CD), is marked by chronic intestinal inflammation and dysregulated immunity. Although UC and CD affect different areas of the gastrointestinal tract, both diseases share aberrant CD4+ memory T cell responses, with HLA-DRB1 as a major genetic risk factor. HLA-DRB1 encodes MHC class II molecules that influence the CD4+ T cell receptor (TCR) repertoire, yet how these genotypes shape TCR specificity in IBD remains unclear. Here, we genotyped HLA-DRB1 and profiled 3.13 million TCRb sequences from circulating memory CD4+ T cells in 33 IBD patients (20 UC, 13 CD) and 14 healthy controls. Using the GLIPH2 algorithm, we distilled 468,441 candidates based on CDR3 amino acid motifs into 440 high-confidence TCR specificity groups significantly enriched among individuals sharing HLA-DRB1 alleles. Notably, five specificity groups were IBD-enriched and shared between UC and CD, suggesting common antigen targets in both diseases. We also observed increased frequencies of clonally expanded cytotoxic GZMB+PRF1+ memory CD4+ T cells and KIRs+CD8+ T cells in a subset of risk-allele carriers with IBD. These findings elucidate distinct, HLA-linked TCR specificity groups in IBD and provide mechanistic insights that may advance antigen discovery and personalized medicine.
Authors
Joshua E. Chan, Azam Mohsin, Jens Krijgsman, Ciska Lindelauf, Qinghui Mu, Brianna Cavalla, Xuhuai Ji, Sarah E. Streett, Vincent van Unen, Mark M. Davis
Abstract
B cells contribute to the pathogenesis of food allergies as they induce allergen-specific antibody production. Clinically-used allergen-specific immunotherapies have shown to induce regulatory B cell (Bregs) subsets as well as target and reduce allergy-driving B cell functions. This report aims to elucidate the contribution of regulatory B cells to an allergen-encapsulating nanoparticle (aeNP) immunotherapy in a murine model of food allergy. In this model, B cells directly associated with aeNPs. CD20+ B cell depletion after aeNP treatment increased the number of mice with severe allergic reactions during oral food challenges and reduced the expansion of regulatory immune cells including CD103+ dendritic cells (DCs) and CCR9+ gut-homing regulatory T cells, indicating that B cells are a component of aeNP immunomodulation. B cell communication in the gastrointestinal tract of aeNP-treated mice identified CD23 signaling as a potential inducer of regulatory CD103+ DC functions and disrupter of allergy-driving B cell-T cell communication. These tolerogenic signaling patterns were also identified in IL-10+ B cells, which have been known to impart regulatory immune effects in both murine and human disease. Ultimately, B cells are a component of the complex immunomodulation leading to aeNP efficacy at reducing allergic reactivity.
Authors
Laila M. Rad, Michael N. Saunders, Laura A. Williams, Katarzyna W. Janczak, Chris L. Dorsett, Kate V. Griffin, Elizabeth J. Bealer, Jeffrey A. Ma, Sayre A. Tillery, Jyotirmoy Roy, Stephen D. Miller, Jessica J. O'Konek, Lonnie D. Shea
Abstract
Immune responses against transgene products can compromise AAV-mediated gene transfer. Although several factors influencing this immunogenicity have been described, the early in vivo events driving CD8+ T cell activation remain poorly defined. Here, we examined antigen presentation kinetics following intramuscular AAV administration in mice. Strikingly, viral genomes were detected in draining lymph nodes as early as one hour post-injection, and transgene-derived peptides were presented to CD8+ T cells from day 1, resulting in progressive activation and first cell divisions detected at day 4. Removal of the injection site demonstrated that AAV particles reaching draining lymph nodes within the first hour were sufficient to induce cytotoxic transgene-specific CD8+ T cells. Finally, AAV vectors incorporating different muscle-specific promoters and regulatory sequences were evaluated. Although muscle-specific, all promoters exhibited variable transgene expression in dendritic cells in vitro, correlating with early T-cell activation in vivo; notably, those associated with higher early antigen presentation induced robust T cell response, whereas reduced presentation correlated with absence of CD8+ T cells. These findings reveal an unexpectedly early onset of transgene-derived epitope presentation, modulated by promoter specificity, which critically shapes CD8+ T cell response. This provides a rationale for evaluating and mitigating AAV immunogenicity in gene therapy design.
Authors
Lindsay Jeanpierre, Coralie Pecquet, Hanadi Saliba, Pauline Finard, Stéphane Terry, Gianni Tavella, Inès Guesmia, Sylvie Boutin, Bérangère Bertin, Sofia Benkhelifa-Ziyyat, Giuseppe Ronzitti, David-Alexandre Gross
Abstract
In chronic beryllium disease (CBD), elevated levels of the inflammatory chemokines CCL3 and CCL4 in the lungs coincide with expanded populations of CD4+ T cells specific to beryllium (Be)-modified peptides derived from these chemokines. Here, we generated HLA-DP2 transgenic (Tg) CCL3-deficient mice (CCL3-/-) that also lack CCL4 to investigate their role in disease development. Be-exposed CCL3-/- mice maintained normal numbers of lung macrophages and dendritic cells (DCs) but exhibited significantly reduced total and HLA-DP2-CCL/Be tetramer-specific CD4+ T cells, IFN-γ-producing CD4+ T cells, and peribronchovascular aggregates, consistent with attenuated inflammation. CCL3 was predominantly expressed in macrophages and DCs, and bone marrow chimera studies confirmed that hematopoietic-derived DCs are the key regulators of CCL/Be-specific CD4+ T cell responses. RNA sequencing of lung-resident CCL4/Be tetramer-positive CD4+ T cells revealed a transcriptional profile enriched for inflammatory and cholesterol-metabolism pathways, with elevated expression of Ifng, Tnf, and Il17a. Moreover, Be-exposed HLA-DP2 Tg mice lacking TNF-α or treated with peptide-MHCII CAR-T cells targeting CCL4/Be-specific CD4+ T cells showed reduced T cell responses and cellular aggregates. These findings demonstrate that CCL3 and CCL4 promote CCL/Be-specific CD4+ T cell responses and highlight peptide-MHCII CAR-T cells as a novel strategy for depleting self-peptide/Be-specific CD4+ T cells in CBD.
Authors
Michael T. Falta, Masoom Raza, Caley J. Nevienski, Tonya M. Brunetti, Rui Fu, Rebecca M. Tucker, Joseph M. Gaballa, Faiz Minhajuddin, Kibrom M. Alula, Alberto Dinarello, Douglas G. Mack, Allison K. Martin, Joseph C. Onyiah, Michael Yarnell, Prashanth Francis, Terry J. Fry, Lisa A. Maier, Andrew P. Fontenot, Charles A. Dinarello, Shaikh M. Atif
Abstract
Human CD4+ T cells utilize nutrients, including lipids, to support their activation and polarization. Considering the pivotal role of lipoproteins in lipid transport, we reasoned that lipoprotein uptake and processing could effect CD4+ T cell function. Here, we demonstrate that activation of human CD4+ T cells induced expression of LDL receptor (LDLR) to facilitate LDLR-mediated endocytosis of LDL. Degradation of surface LDLR on CD4+ T cells with PCSK9 hampered activation and proliferation of the cells. Lipoprotein deprivation or blocking of lysosomal cholesterol egress impaired activation of mechanistic target of rapamycin complex 1 (mTORC1), affecting CD4+ T cell activation and proliferation. Furthermore, lipoprotein deprivation of cultured primary CD4+ T cells lead to reduced expression of c-MAF and FOXP3, key transcription factors for IL-10, accompanied by reduced IL-10 secretion. The pivotal role of LDLR-mediated lipoprotein uptake for mTORC1 activity, c-MAF and FOXP3 expression, and IL-10 secretion was confirmed using LDLR-dysfunctional CD4+ T cells from patients with homozygous familial hypercholesterolemia. Our study offers valuable insights into the lipoprotein metabolism of human CD4+ T cells and their reliance on the LDLR pathway for activation and polarization, a feature that may be leveraged to modulate CD4+ T cell function.
Authors
Angela Markovska, Niels S. van Heusden, Dagmar Duijzer, Alejandra Bodelón, Greta Rogani, Enric Mocholi, Edwin C.A. Stigter, Can Gulersonmez, Sander Kooijman, Leonie Van der Zee, Monique T. Mulder, Jeanine E. Roeters van Lennep, Patrick C.N. Rensen, Jorg van Loosdregt, Sebastiaan J. Vastert, Noam Zelcer, Marianne Boes, Henk S. Schipper
Abstract
Stem cell–derived β cells offer a promising approach for type 1 diabetes (T1D) treatment. However, the processes of graft infiltration and rejection by immune cells remain poorly understood in humans. In this study, autologous or allogeneic stem cell–derived islets (SC-islets) were transplanted in human immune system mice and analyzed 14 to 18 weeks later. Imaging mass cytometry revealed unique characteristics of SC-islet grafts, including a high percentage of glucagon+ cells and the presence of cysts and CD57+ enterochromaffin cells, features not typically observed in endogenous or transplanted allogeneic primary pancreatic islets. Allogeneic SC-islet grafts exhibited heavy immune infiltration, cell proliferation, and pro-fibrotic processes, whereas autologous grafts showed minimal infiltration and little fibrosis. In some mice, autologous T cells expressing islet antigen-reactive (IAR) T cell receptors (TCRs) were adoptively transferred. Three weeks after transfer, autologous grafts injected with IAR-TCR+ T cells showed negligible immune infiltration, even though IAR-TCR+ T cells were detected in the spleen. Under the conditions tested, human SC-islet grafts were not rejected by an autologous immune system, even in the presence of autoreactive T cells, pointing to several limitations that remain to be addressed for a model of spontaneous autologous SC-islet infiltration and destruction.
Authors
Camillo Bechi Genzano, Giorgia Zanetti, Qian Du, Daniel Traum, Deeksha Lahori, Grant M. Downes, Sakshi A. Bhatele, Xiaolan Ding, Kyle D. Apley, Rebuma Firdessa Fite, Matthew Ishahak, Enrique Eduardo Sanchez-Castro, Jeffrey R. Millman, Yiming Luo, Klaus H. Kaestner, Cory Berkland, Dieter Egli, Megan Sykes, Remi J. Creusot
Abstract
BK polyomavirus–associated nephropathy (BKVN) adversely impacts kidney allograft survival and often mimics acute T cell–mediated rejection (TCMR), confounding diagnosis and management. To address this conundrum, we performed unbiased RNA sequencing of urinary cells matched to biopsies classified as BKVN with intragraft inflammation (BKVN-P), BKVN without inflammation (BKVN-N), TCMR, or no rejection (NR). BKVN-N displayed dominant host DNA replication, cell cycle, and repair programs, while BKVN-P samples exhibited expansive innate immune activation, antigen presentation, chemokine upregulation, and epithelial injury. Both BKVN subtypes shared signatures of T cell exhaustion and mature and tolerogenic dendritic cell activation but differed in immune orientation — Th1 predominance in BKVN-N versus Treg and CD8 enrichment in BKVN-P. Compared with TCMR samples, BKVN-P lacked robust TCR/CD28 signaling and was enriched for viral and innate modules; BKVN-N lacked alloimmune activation. B cell exhaustion characterized BKVN-N, while BKVN-P displayed robust B cell activation with metabolic downregulation. A ratiometric urinary cell biomarker, CXCL10 mRNA/CD3E mRNA, distinguished both BKVN subtypes from TCMR with diagnostic accuracy, replicated by quantitative reverse transcription PCR for clinical translation, and confirmed in an independent cohort. These findings demonstrate the utility of urinary cell transcriptomics for resolving viral injury from alloimmunity, enabling precision diagnostics and targeted immunomodulation in kidney transplantation.
Authors
Franco B. Mueller, Carol Li, Darshana M. Dadhania, Surya V. Seshan, Thalia Salinas, Vijay K. Sharma, Jenny Z. Xiang, Hans H. Hirsch, Thangamani Muthukumar, Manikkam Suthanthiran
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