Immunology and Infectious Disease Commons^™

Pipecolic Acid And Novel Insights Into Cerebral Malaria, Akua E. Mensah

Theses

Cerebral malaria (CM), a severe manifestation of Plasmodium infection, prompts our investigation into the nuanced role of pipecolic acid in its pathophysiology. To unravel the molecular intricacies, we conducted in vitro lysine labeling techniques of mice infected with P. berghei ANKA parasites, and human P. falciparum grown in vitro, aiming to discern the impact of Plasmodium on pipecolic acid production. Previous observations indicated an elevation in pipecolic acid levels correlating with neurological decline in children with CM. In our study, confirming elevated pipecolic acid presence in the plasma and brain tissues of CM patients and the animal model of CM, …

Tgf-B Signaling Mechanisms In Caenorhabditis Elegans Response To Bacterial Pathogens, Emma J. Ciccarelli

Dissertations, Theses, and Capstone Projects

When exposed to infection, the nematode C. elegans mounts an innate immune response through secretion of antimicrobial peptides (AMPs). Different signaling pathways in the worm regulate release of these AMPs. One highly conserved pathway is the C. elegans BMP like pathway – regulated by the ligand DBL-1. The DBL-1 pathway is noted for its significant role in development but has also been shown to regulate many post-developmental processes within the worm, including the immune response. We are interested in determining how DBL-1 signaling can mediate a response specific to immunity, separate from its other functions in the worm. Through survival …

Function Of Atm And Msh2 During Dna Repair And Recombination, Emily Sible

Dissertations, Theses, and Capstone Projects

Class switch recombination (CSR) produces secondary immunoglobulin isotypes and requires AID-dependent DNA deamination of intronic switch (S) regions within the immunoglobulin heavy chain (Igh) gene locus. Non-canonical repair of deaminated DNA by mismatch repair (MMR) or base excision repair (BER) creates DNA breaks that permit recombination between distal S regions. ATM-dependent phosphorylation of AID at serine-38 (pS38-AID) promotes its interaction with APE1, a BER protein, suggesting that ATM regulates CSR through BER. However, pS38-AID may also function in MMR during CSR, although the mechanism remains unknown. To examine whether ATM modulates BER- and/or MMR-dependent CSR, Atm^-/- mice …

Nlrp10 Enhances Cd4+ T-Cell-Mediated Ifnγ Response Via Regulation Of Dendritic Cell-Derived Il-12 Release, Maurizio Vacca, Julia Böhme, Lisa Zambetti, Hanif Javanmard Khameneh, Bhairav S. Paleja, Federica Laudisi, Adrian W. S. Ho, Kurt Neo, Keith Weng Kit Leong, Mardiana Marzuki, Bernett Lee, Michael Poidinger, Laura Santambrogio, Liana Tsenova, Francesca Zolezzi, Gennaro De Libero, Amit Singhal, Alessandra Mortellaro

Publications and Research

NLRP10 is a nucleotide-binding oligomerization domain-like receptor that functions as an intracellular pattern recognition receptor for microbial products. Here, we generated a Nlrp10−/− mouse to delineate the role of NLRP10 in the host immune response and found that Nlrp10−/− dendritic cells (DCs) elicited sub-optimal IFNγ production by antigenspecific CD4+ T cells compared to wild-type (WT) DCs. In response to T-cell encounter, CD40 ligation or Toll-like receptor 9 stimulation, Nlrp10−/− DCs produced low levels of IL-12, due to a substantial decrease in NF-κB activation. Defective IL-12 production was also evident in vivo and affected IFNγ production by CD4+ T cells. Upon …

Ifn-G Induces Histone 3 Lysine 27 Trimethylation In A Small Subset Of Promoters To Stably Silence Gene Expression In Human Macrophages, Yu Qiao, Kyuho Kang, Eugenia Giannopoulou, Celeste Fang, Lionel B. Ivashkiv

Publications and Research

The mechanisms by which IFN-g activates expression of interferon-stimulated genes that have inflammatory and host defense functions are well understood. In contrast, little is known about how IFN-g represses gene expression. By using transcriptomic and epigenomic analysis, we found that stable repression of a small group of genes by IFN-g is associated with recruitment of the histone methyltransferase EZH2 and deposition of the negative mark histone 3 lysine 27 trimethylation (H3K27me3) at their promoters. Repressed genes included MERTK, PPARG, and RANK, which have anti-inflammatory functions and promote osteoclast differentiation. Gene repression and H3K27me3 persisted after IFN-g signaling was terminated, and …

Receptor-Type Guanylyl Cyclase At 76c (Gyc76c) Regulates De Novo Lumen Formation During Drosophila Tracheal Development, Monn Monn Myat, Unisha Patel

Publications and Research

Lumen formation and maintenance are important for the development and function of essential organs such as the lung, kidney and vasculature. In the Drosophila embryonic trachea, lumena formde novo to connect the different tracheal branches into an interconnected network of tubes. Here, we identify a novel role for the receptor type guanylyl cyclase at 76C (Gyc76C) in de novo lumen formation in the Drosophila trachea.We show that in embryosmutant for gyc76C or its downsteam effector protein kinase G (PKG) 1, tracheal lumena are disconnected. Dorsal trunk (DT) cells of gyc76C mutant embryos migrate to contact each other and complete the …

Geospatial Resolution Of Human And Bacterial Diversity With City-Scale Metagenomics, Ebrahim Afshinnekoo, Cem Meydan, Shanin Chowdhury, Dyala Jaroudi, Collin Boyer, Nick Bernstein, Julia M. Maritz, Darryl Reeves, Jorge Gandara, Sagar Chhangawala, Sofia Ahsanuddin, Amber Simmons, Timothy Nessel, Bharathi Sundaresh, Elizabeth Pereira, Ellen Jorgensen, Sergios-Orestis Kolokotronis, Nell Kirchberger, Isaac Garcia, David Gandara, Sean Dhanraj, Tanzina Nawrin, Yogesh Saletore, Noah Alexander, Priyanka Vijay, Elizabeth M. Hénaff, Paul Zumbo, Michael Walsh, Gregory D. O'Mullan, Scott Tighe, Joel T. Dudley, Anya Dunaif, Sean Ennis, Eoghan O'Halloran, Tiago R. Magalhaes, Braden Boone, Angela L. Jones, Theodore R. Muth, Katie Schneider Paolantonio, Elizabeth Alter, Eric E. Schadt, Jeanne Garbarino, Robert J. Prill, Jane M. Carlton, Shawn Levy, Christopher E. Mason

Publications and Research

The panoply of microorganisms and other species present in our environment influence human health and disease, especially in cities, but have not been profiled with metagenomics at a city-wide scale. We sequenced DNA from surfaces across the entire New York City (NYC) subway system, the Gowanus Canal, and public parks. Nearly half of the DNA (48%) does not match any known organism; identified organisms spanned 1,688 bacterial, viral, archaeal, and eukaryotic taxa, which were enriched for harmless genera associated with skin (e.g., Acinetobacter). Predicted ancestry of human DNA left on subway surfaces can recapitulate U.S. Census demographic data, and bacterial …

Tcr Alpha Lcr And Non-Lcr Cis-Elements Contributing To Tissue Specific Expression Of The Tcr Alpha Gene In Thymic And Peripheral T Cells, Martina Kucerova-Levisohn

Dissertations, Theses, and Capstone Projects

Orchestrated expression of multiple genes residing in the complex TCRα/δ/Dad1 locus requires tight control from multiple cis-acting elements. The TCRα locus control region (LCR), is positioned between TCRα and Dad1 gene, and has been implicated in the differential expression of both genes. In this study, we focus our work on the hypersensitive site (HS)1 prime (HS1'), located 3' of the classical Eα enhancer, within the TCRα LCR. We investigated its non- redundant role in TCRα expression in thymic and peripheral T cells as assayed by in vivo and in vitro studies. Furthermore, formation of HS1' in both lymphoid and …

Development And Maintenance Of Thymic Epithelial Microenvironment, Varan J. Singh

Dissertations and Theses

Thymus is a primary lymphoid organ responsible for proper development and selection Of T-­‐cells. The thymic microenvironment, however, undergoes age related involution, Resulting in a reduction of the repertoire of T-­‐cells that are produced, and a decreased Capacity to respond to new antigen. Even though significant thymic epithelial turnover occurs, it is unclear if postnatal thymic progenitors/stem cell are responsible for the maintenance of the TEC microenvironment. Here we use the K5rtTA:TetO-­‐H2BGFP transgenic model to identify a slow cycling potential stem cells/progenitor population in the postnatal thymus. These cells were isolated, expanded in culture, and successfully differentiated into adipocytes, chondrocytes …

Association Between Symptomatic Vulvovaginal Candidiasis And Hiv Rna Levels In Plasma And Genital Secretions Among Women On Haart, Teke Apalata, William H. Carr, Benjamin Longo-Mbenza, Willem A. Sturm, P. Moodley

Publications and Research

Background. Genital tract (GT) inflammation plays a major role in HIV transmission. We aimed to determine the association between symptomatic vulvovaginal candidiasis (VVC) and HIV RNA levels in plasma and GTs of HIV-infected women on highly active antiretroviral therapy (HAART).

Method. Women with VVC on HAART were recruited from a primary healthcare clinic in KwaZulu-Natal Province, South Africa, between June 2011 and December 2011. VVC was diagnosed clinically, supported by Gram staining and culture of genital secretions. HIV RNA load was determined by reverse transcription polymerase chain reaction. CD4+ counts were obtained from patients’ medical records.

Results. Plasma HIV RNA …

Structure-Function Analysis Of Zapc, An Ftsz-Ring Stabilizer, In Escherichia Coli Cytokinesis, Lukasz Tchorzewski

Dissertations and Theses

In Escherichia coli, cell division is defined by the polymerization and constriction of a cytokinetic ring (Z ring) formed by FtsZ, a tubulin-like GTPase, at midcell. Division also involves the formation of a multi-protein complex at midcell known as the divisome. Several divisome proteins promote the assembly/disassembly processes of FtsZ, thereby exercising spatiotemporal control over division. Among FtsZ regulatory proteins are the FtsZ ringassociated proteins (Zap), which either directly or indirectly stabilize the Z-ring by increasing lateral interactions amongst FtsZ protofilaments in the Z-ring. ZapA-D are recruited during early cytokinesis and have overlapping functions in stabilizing FtsZ at midcell, but …

Changes In Natural Killer Cell Activation And Function During Primary Hiv-1 Infection, Vivek Naranbhai, Marcus Altfeld, Salim S. Abdool Karim, Thumbi Ndung’U, Quarraisha Abdool Karim, William H. Carr

Publications and Research

Background: Recent reports suggest that Natural Killer (NK) cells may modulate pathogenesis of primary HIV-1 infection. However, HIV dysregulates NK-cell responses. We dissected this bi-directional relationship to understand how HIV impacts NK-cell responses during primary HIV-1 infection.

Methodology/Principal Findings: Paired samples from 41 high-risk, initially HIV-uninfected CAPRISA004 participants were analysed prior to HIV acquisition, and during viraemic primary HIV-1 infection. At the time of sampling post-infection five women were seronegative, 11 women were serodiscordant, and 25 women were seropositive by HIV-1 rapid immunoassay. Flow cytometry was used to measure NK and T-cell activation, NK-cell receptor expression, cytotoxic and cytokine-secretory functions, …

Polyglutamine Toxicity Is Controlled By Prion Composition And Gene Dosage In Yeast, He Gong, Nina V. Romanova, Kim D. Allen, Pavithra Chandramowlishwaran, Kavita Gokhale, Gary P. Newnam, Piotr Miceczkowski, Michael Y. Sherman, Yury O. Chernoff

Publications and Research

Polyglutamine expansion causes diseases in humans and other mammals. One example is Huntington’s disease. Fragments of human huntingtin protein having an expanded polyglutamine stretch form aggregates and cause cytotoxicity in yeast cells bearing endogenous QN-rich proteins in the aggregated (prion) form. Attachment of the proline(P)-rich region targets polyglutamines to the large perinuclear deposit (aggresome). Aggresome formation ameliorates polyglutamine cytotoxicity in cells containing only the prion form of Rnq1 protein. Here we show that expanded polyglutamines both with (poly-QP) or without (poly-Q) a P-rich stretch remain toxic in the presence of the prion form of translation termination (release) factor Sup35 (eRF3). …

Role For Sumoylation In Systemic Inflammation And Immune Homeostasis In Drosophila Larvae, Indira Paddibhatla, Mark J. Lee, Marta E. Kalamarz, Roberto Ferrarese, Shubha Govind

Publications and Research

To counter systemic risk of infection by parasitic wasps, Drosophila larvae activate humoral immunity in the fat body and mount a robust cellular response resulting in encapsulation of the wasp egg. Innate immune reactions are tightly regulated and are resolved within hours. To understand the mechanisms underlying activation and resolution of the egg encapsulation response and examine if failure of the latter develops into systemic inflammatory disease, we correlated parasitic wasp-induced changes in the Drosophila larva with systemic chronic conditions in sumoylation-deficient mutants. We have previously reported that loss of either Cactus, the Drosophila (IkB) protein or Ubc9, the SUMO-conjugating …

Contrasting Infection Strategies In Generalist And Specialist Wasp Parasitoids Of Drosophila Melanogaster, Todd A. Schlenke, Jorge Morales, Shubha Govind, Andrew G. Clark

Publications and Research

Although host–parasitoid interactions are becoming well characterized at the organismal and cellular levels, much remains to be understood of the molecular bases for the host immune response and the parasitoids’ ability to defeat this immune response. Leptopilina boulardi and L. heterotoma, two closely related, highly infectious natural parasitoids of Drosophila melanogaster, appear to use very different infection strategies at the cellular level. Here, we further characterize cellular level differences in the infection characteristics of these two wasp species using newly derived, virulent inbred strains, and then use whole genome microarrays to compare the transcriptional response of Drosophila to each. While …