B2-adrenergic receptor-mediated negative regulation of group 2 innate lymphoid cell responses
       
     
Arginase 1 is an innate lymphoid-cell-intrinsic metabolic checkpoint controlling type 2 inflammation
       
     
Spatial Map of Human T Cell Compartmentalization and Maintenance over Decades of Life
       
     
Human memory T cells: generation, compartmentalization and homeostasis
       
     
Expansion of HIV-specific T follicular helper cells in chronic HIV infection
       
     
Distribution and compartmentalization of human circulating and tissue-resident memory T cell subsets
       
     
Application of the systematic “DAmP” approach to create a partially defective C. albicans mutant
       
     
B2-adrenergic receptor-mediated negative regulation of group 2 innate lymphoid cell responses
       
     
B2-adrenergic receptor-mediated negative regulation of group 2 innate lymphoid cell responses

Saya Moriyama, Jonathan R. Brestoff, Anne-Laure Flamar, Jesper B. Moeller, Christoph S. N. Klose, Lucille C. Rankin, Naomi A. Yudanin, Laurel A. Monticelli, Gregory Garbès Putzel, Hans-Reimer Rodewald, David Artis

 

The type 2 inflammatory response is induced by various environmental and infectious stimuli. Although recent studies identified group 2 innate lymphoid cells (ILC2s) as potent sources of type 2 cytokines, the molecular pathways controlling ILC2 responses are incompletely defined. Here we demonstrate that murine ILC2s express the b2-adrenergic receptor (b2AR) and colocalize with adrenergic neurons in the intestine. b2AR deficiency resulted in exaggerated ILC2 responses and type 2 inflammation in intestinal and lung tissues. Conversely, b2AR agonist treatment was associated with impaired ILC2 responses and reduced inflammation in vivo. Mechanistically, we demonstrate that the b2AR pathway is a cell-intrinsic negative regulator of ILC2 responses through inhibition of cell proliferation and effector function. Collectively, these data provide the first evidence of a neuronalderived regulatory circuit that limits ILC2-dependent type 2 inflammation.

Arginase 1 is an innate lymphoid-cell-intrinsic metabolic checkpoint controlling type 2 inflammation
       
     
Arginase 1 is an innate lymphoid-cell-intrinsic metabolic checkpoint controlling type 2 inflammation

Laurel A Monticelli, Michael D Buck, Anne-Laure Flamar, Steven A Saenz, Elia D Tait Wojno, Naomi A Yudanin, Lisa C Osborne, Matthew R Hepworth, Sara V Tran, Hans-Reimer Rodewald, Hardik Shah, Justin R Cross, Joshua M Diamond, Edward Cantu, Jason D Christie, Erika L Pearce & David Artis

Group 2 innate lymphoid cells (ILC2s) regulate tissue inflammation and repair after activation by cell-extrinsic factors such as host-derived cytokines. However, the cell-intrinsic metabolic pathways that control ILC2 function are undefined. Here we demonstrate that expression of the enzyme arginase-1 (Arg1) during acute or chronic lung inflammation is a conserved trait of mouse and human ILC2s. Deletion of mouse ILC-intrinsic Arg1 abrogated type 2 lung inflammation by restraining ILC2 proliferation and dampening cytokine production. Mechanistically, inhibition of Arg1 enzymatic activity disrupted multiple components of ILC2 metabolic programming by altering arginine catabolism, impairing polyamine biosynthesis and reducing aerobic glycolysis. These data identify Arg1 as a key regulator of ILC2 bioenergetics that controls proliferative capacity and proinflammatory functions promoting type 2 inflammation.

Spatial Map of Human T Cell Compartmentalization and Maintenance over Decades of Life
       
     
Spatial Map of Human T Cell Compartmentalization and Maintenance over Decades of Life

Naomi Yudanin,*Joseph J. C. Thome*,  Yoshiaki Ohmura, Masaru Kubota, Boris Grinshpun, Taheri Sathaliyawala, Tomoaki Kato, Harvey Lerner, Yufeng Shen, and Donna L. Farber

* Equal Contribution

Mechanisms for human memory T cell differentiation and maintenance have largely been inferred from studies of peripheral blood, though the majority of T cells are found in lymphoid and mucosal sites. We present here a multidimensional, quantitative analysis of human T cell compartmentalization and maintenance over six decades of life in blood, lymphoid, and mucosal tissues obtained from 56 individual organ donors. Our results reveal that the distribution and tissue residence of naive, central, and effector memory, and terminal effector subsets is contingent on both their differentiation state and tissue localization. Moreover, T cell homeostasis driven by cytokine or TCR-mediated signals is different in CD4+ or CD8+ T cell lineages, varies with their differentiation stage and tissue localization, and cannot be inferred from blood. Our data provide an unprecedented spatial and temporal map of human T cell compartmentalization and maintenance, supporting distinct pathways for human T cell fate determination and homeostasis. 

Human memory T cells: generation, compartmentalization and homeostasis
       
     
Human memory T cells: generation, compartmentalization and homeostasis

Donna L. Farber, Naomi A. Yudanin & Nicholas P. Restifo

Memory T cells constitute the most abundant lymphocyte population in the body for the majority of a person's lifetime; however, our understanding of memory T cell generation, function and maintenance mainly derives from mouse studies, which cannot recapitulate the exposure to multiple pathogens that occurs over many decades in humans. In this Review, we discuss studies focused on human memory T cells that reveal key properties of these cells, including subset heterogeneity and diverse tissue residence in multiple mucosal and lymphoid tissue sites. We also review how the function and the adaptability of human memory T cells depend on spatial and temporal compartmentalization.

Expansion of HIV-specific T follicular helper cells in chronic HIV infection
       
     
Expansion of HIV-specific T follicular helper cells in chronic HIV infection

Madelene Lindqvist, Jan van Lunzen, Damien Z. Soghoian, Bjorn D. Kuhl, Srinika Ranasinghe, Gregory Kranias, Michael D. Flanders, Samuel Cutler, Naomi Yudanin, Matthias I. Muller, Isaiah Davis, Donna Farber, Philip Hartjen, Friedrich Haag, Galit Alter, Julian Schulze zur Wiesch, and Hendrik Streeck

HIV targets CD4 T cells, which are required for the induction of high-affinity antibody responses and the formation of long-lived B cell memory. The depletion of antigen-specific CD4 T cells during HIV infection is therefore believed to impede the development of protective B cell immunity. Although several different HIV-related B cell dysfunctions have been described, the role of CD4 T follicular helper (TFH) cells in HIV infection remains unknown. Here, we assessed HIV-specific TFH responses in the lymph nodes of treatment-naive and antiretroviral-treated HIV-infected individuals. Strikingly, both the bulk TFH and HIV-specific TFH cell populations were significantly expanded in chronic HIV infection and were highly associated with viremia. In particular, GAG-specific TFH cells were detected at significantly higher levels in the lymph nodes compared with those of GP120-specific TFH cells and showed preferential secretion of the helper cytokine IL-21. In addition, TFH cell expansion was associated with an increase of germinal center B cells and plasma cells as well as IgG1 hypersecretion. Thus, our study suggests that high levels of HIV viremia drive the expansion of TFH cells, which in turn leads to perturbations of B cell differentiation, resulting in dysregulated antibody production.

Distribution and compartmentalization of human circulating and tissue-resident memory T cell subsets
       
     
Distribution and compartmentalization of human circulating and tissue-resident memory T cell subsets

Taheri Sathaliyawala, Masaru Kubota, Naomi Yudanin, Damian Turner, Philip Camp, Joseph J. C. Thome,Kara L. Bickham, Harvey Lerner, Michael Goldstein, Megan Sykes, Tomoaki Kato, and Donna L. Farber

Knowledge of human T cells derives chiefly from studies of peripheral blood, whereas their distribution and function in tissues remains largely unknown. Here, we present a unique analysis of human T cells in lymphoid and mucosal tissues obtained from individual organ donors, revealing tissue-intrinsic compartmentalization of naive, effector, and memory subsets conserved between diverse individuals. Effector memory CD4(+) T cells producing IL-2 predominated in mucosal tissues and accumulated as central memory subsets in lymphoid tissue, whereas CD8(+) T cells were maintained as naive subsets in lymphoid tissues and IFN-γ-producing effector memory CD8(+) T cells in mucosal sites. The T cell activation marker CD69 was constitutively expressed by memory T cells in all tissues, distinguishing them from circulating subsets, with mucosal memory T cells exhibiting additional distinct phenotypic and functional properties. Our results provide an assessment of human T cell compartmentalization as a new baseline for understanding human adaptive immunity.

 

Application of the systematic “DAmP” approach to create a partially defective C. albicans mutant
       
     
Application of the systematic “DAmP” approach to create a partially defective C. albicans mutant

JS Finkel, N Yudanin, JE Nett, DR Andes, and AP Mitchell

An understanding of gene function often relies upon creating multiple kinds of alleles. Functional analysis in Candida albicans, a major fungal pathogen, has generally included characterization of mutant strains with insertion or deletion alleles and over-expression alleles. Here we use in C. albicans another type of allele that has been employed effectively in the model yeast Saccharomyces cerevisiae, a “Decreased Abundance by mRNA Perturbation” (DAmP) allele. DAmP alleles are created systematically through replacement of 3′ noncoding regions with nonfunctional heterologous sequences, and thus are broadly applicable. We used a DAmP allele to probe the function of Sun41, a surface protein with roles in cell wall integrity, cell-cell adherence, hyphal formation, and biofilm formation that has been suggested as a possible therapeutic target. ASUN41-DAmP allele results in approximately 10-fold reduced levels of SUN41 RNA, and yields intermediate phenotypes in most assays. We report that a sun41Δ/Δ mutant is defective in biofilm formation in vivo, and that the SUN41-DAmP allele complements that defect. This finding argues that Sun41 may not be an ideal therapeutic target for biofilm inhibition, since a 90% decrease in activity has little effect on biofilm formation in vivo. We anticipate that DAmP alleles of C. albicans genes will be informative for analysis of other prospective drug targets, including essential genes.