Transcriptome profiles derived from the site of human disease have led to the identification of genes that contribute to pathogenesis, yet the complex mixture of cell types in these lesions has been an obstacle for defining specific mechanisms. Leprosy provides an outstanding model to study host defense and pathogenesis in a human infectious disease, given its clinical spectrum, which interrelates with the host immunologic and pathologic responses. Here, we investigated gene expression profiles derived from skin lesions for each clinical subtype of leprosy, analyzing gene coexpression modules by cell-type deconvolution. In lesions from tuberculoid leprosy patients, those with the self-limited form of the disease, dendritic cells were linked with
Megan S. Inkeles, Rosane M.B. Teles, Delila Pouldar, Priscila R. Andrade, Cressida A. Madigan, David Lopez, Mike Ambrose, Mahdad Noursadeghi, Euzenir N. Sarno, Thomas H. Rea, Maria T. Ochoa, M. Luisa Iruela-Arispe, William R. Swindell, Tom H.M. Ottenhoff, Annemieke Geluk, Barry R. Bloom, Matteo Pellegrini, Robert L. Modlin
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a pregnancy-related condition caused by maternal antibodies binding an alloantigen on fetal platelets. In most cases the alloantigen is formed by a single amino acid, integrin β3 Leu33, referred to as human platelet antigen–1a (HPA-1a). Production of anti–HPA-1a antibodies likely depends on CD4+ T cells that recognize the same alloantigen in complex with the HLA-DRA/DRB3*01:01 molecule. While this complex is well characterized, T cell recognition of it is not. Here, to examine the nature of antigen recognition by HPA-1a–specific T cells, we assayed native and synthetic variants of the integrin β3 peptide antigen for binding to DRA/DRB3*01:01-positive antigen-presenting cells and for T cell activation. We found that HPA-1a–specific T cells recognize non-allogeneic integrin β3 residues anchored to DRA/DRB3*01:01 by the allogeneic Leu33, which itself is not directly recognized by these T cells. Furthermore, these T cell responses are diverse, with different T cells depending on different residues for recognition. This represents a unique form of indirect allorecognition in which a non-allogeneic peptide sequence becomes immunogenic by stable anchoring to MHC by an allogeneic residue.
Maria Therese Ahlen, Anne Husebekk, Ida Løken Killie, Bjørn Skogen, Tor Brynjar Stuge
Genome-wide association studies of asthma have identified genetic variants in the
Erin D. Gordon, Joe Palandra, Agata Wesolowska-Andersen, Lando Ringel, Cydney L. Rios, Marrah E. Lachowicz-Scroggins, Louis Z. Sharp, Jamie L. Everman, Hannah J. MacLeod, Jae W. Lee, Robert J. Mason, Michael A. Matthay, Richard T. Sheldon, Michael C. Peters, Karl H. Nocka, John V. Fahy, Max A. Seibold
In carcinogen-driven cancers, a high mutational burden results in neoepitopes that can be recognized immunologically. Such carcinogen-induced tumors may evade this immune response through “immunoediting,” whereby tumors adapt to immune pressure and escape T cell–mediated killing. Many tumors lack a high neoepitope burden, and it remains unclear whether immunoediting occurs in such cases. Here, we evaluated T cell immunity in an autochthonous mouse model of pancreatic cancer and found a low mutational burden, absence of predicted neoepitopes derived from tumor mutations, and resistance to checkpoint immunotherapy. Spontaneous tumor progression was identical in the presence or absence of T cells. Moreover, tumors arising in T cell–depleted mice grew unchecked in immune-competent hosts. However, introduction of the neoantigen ovalbumin (OVA) led to tumor rejection and T cell memory, but this did not occur in OVA immune-tolerant mice. Thus, immunoediting does not occur in this mouse model — a likely consequence, not a cause, of absent neoepitopes. Because many human tumors also have a low missense mutational load and minimal neoepitope burden, our findings have clinical implications for the design of immunotherapy for patients with such tumors.
Rebecca A. Evans, Mark S. Diamond, Andrew J. Rech, Timothy Chao, Max W. Richardson, Jeffrey H. Lin, David L. Bajor, Katelyn T. Byrne, Ben Z. Stanger, James L. Riley, Nune Markosyan, Rafael Winograd, Robert H. Vonderheide
Patrick H. Lizotte, Elena V. Ivanova, Mark M. Awad, Robert E. Jones, Lauren Keogh, Hongye Liu, Ruben Dries, Christina Almonte, Grit S. Herter-Sprie, Abigail Santos, Nora B. Feeney, Cloud P. Paweletz, Meghana M. Kulkarni, Adam J. Bass, Anil K. Rustgi, Guo-Cheng Yuan, Donald W. Kufe, Pasi A. Jänne, Peter S. Hammerman, Lynette M. Sholl, F. Stephen Hodi, William G. Richards, Raphael Bueno, Jessie M. English, Mark A. Bittinger, Kwok-Kin Wong
Fibrosis is a shared end-stage pathway to lung, liver, and heart failure. In the ocular mucosa (conjunctiva), fibrosis leads to blindness in trachoma, pemphigoid, and allergy. The indirect fibrogenic role of DCs via T cell activation and inflammatory cell recruitment is well documented. However, here we demonstrate that DCs can directly induce fibrosis. In the mouse model of allergic eye disease (AED), classical CD11b+ DCs in the ocular mucosa showed increased activity of aldehyde dehydrogenase (ALDH), the enzyme required for retinoic acid synthesis. In vitro, CD11b+ DC–derived ALDH was associated with 9-
Sarah D. Ahadome, Rose Mathew, Nancy J. Reyes, Priyatham S. Mettu, Scott W. Cousins, Virginia L. Calder, Daniel R. Saban
Systemic sclerosis (SSc) is a potentially fatal autoimmune disorder with limited therapeutic options. Sclerodermatous graft versus host disease (sclGvHD), induced by transfer of B10.D2 splenocytes into BALB/c
Katia Urso, David Alvarez, Viviana Cremasco, Kelly Tsang, Angelo Grauel, Robert Lafyatis, Ulrich H. von Andrian, Joerg Ermann, Antonios O. Aliprantis
Following the advent of molecular assays that measure T cell receptor excision circles (TRECs) present in recent thymic emigrants, it has been conclusively shown that thymopoiesis persists in most adults, but that functional output decreases with age, influencing the maintenance of a diverse and functional T cell receptor (TCR) repertoire. Space flight has been shown to result in a variety of phenotypic and functional changes in human T cells and in the reactivation of latent viruses. While space flight has been shown to influence thymic architecture in rodents, thymopoiesis has not previously been assessed in astronauts. Here, we assessed thymopoiesis longitudinally over a 1-year period prior to and after long-term space flight (median duration, 184 days) in 16 astronauts. While preflight assessments of thymopoiesis remained quite stable in individual astronauts, we detected significant suppression of thymopoiesis in all subjects upon return from space flight. We also found significant increases in urine and plasma levels of endogenous glucocorticoids coincident with the suppression of thymopoiesis. The glucocorticoid induction and thymopoiesis suppression were transient, and they normalized shortly after return to Earth. This is the first report to our knowledge to prospectively demonstrate a significant change in thymopoiesis in healthy individuals in association with a defined physiologic emotional and physical stress event. These results suggest that suppression of thymopoiesis has the potential to influence the maintenance of the TCR repertoire during extended space travel. Further studies of thymopoiesis and endogenous glucocorticoids in other stress states, including illness, are warranted.
Cara L. Benjamin, Raymond P. Stowe, Lisa St. John, Clarence F. Sams, Satish K. Mehta, Brian E. Crucian, Duane L. Pierson, Krishna V. Komanduri
Over one-fifth of North American women of childbearing age are obese, putting these women at risk for a variety of detrimental chronic diseases. In addition, obesity increases the risk for developing major complications during pregnancy. The mechanisms by which obesity contributes to pregnancy complications and loss remain unknown. Increasing evidence indicates that obesity results in major changes to adipose tissue immune cell composition and function; whether or not obesity also affects immune function in the uterus has not been explored. Here we investigated the effect of obesity on uterine natural killer (uNK) cells, which are essential for uterine artery remodeling and placental development. Using a cohort of obese or lean women, we found that obesity led to a significant reduction in uNK cell numbers accompanied with impaired uterine artery remodeling. uNK cells isolated from obese women had altered expression of genes and pathways associated with extracellular matrix remodeling and growth factor signaling. Specifically, uNK cells were hyper-responsive to PDGF, resulting in overexpression of decorin. Functionally, decorin strongly inhibited placental development by limiting trophoblast survival. Together, these findings establish a potentially new link between obesity and poor pregnancy outcomes, and indicate that obesity-driven changes to uterine-resident immune cells critically impair placental development.
Sofie Perdu, Barbara Castellana, Yoona Kim, Kathy Chan, Lauren DeLuca, Alexander G. Beristain
Suresh Gopi Kalathil, Amit Anand Lugade, Austin Miller, Renuka Iyer, Yasmin Thanavala
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