A5037652685- T-cell and B-cell Immunology
- Immune Cell Function and Interaction
- Immunotherapy and Immune Responses
- Immune Response and Inflammation
- Complement system in diseases
- Monoclonal and Polyclonal Antibodies Research
- Malaria Research and Control
- Cell Adhesion Molecules Research
- Erythrocyte Function and Pathophysiology
- Tuberculosis Research and Epidemiology
- HIV Research and Treatment
- Cellular transport and secretion
- Systemic Lupus Erythematosus Research
- Medical Imaging and Pathology Studies
- Chemical and Physical Studies
- Galectins and Cancer Biology
- Adrenal and Paraganglionic Tumors
- Ocular Infections and Treatments
- Ocular Diseases and Behçet’s Syndrome
- Inflammatory mediators and NSAID effects
- NF-κB Signaling Pathways
- Cellular Mechanics and Interactions
- Immunodeficiency and Autoimmune Disorders
- Blood properties and coagulation
- Protein Kinase Regulation and GTPase Signaling
National Institute of Allergy and Infectious Diseases
2015-2025
Seoul National University
1997-2023
National Institutes of Health
2010-2023
Immungenetics (Germany)
2020
Catholic University of Korea
1993-2011
Protective antibodies in Plasmodium falciparum malaria are only acquired after years of repeated infections. Chronic exposure is associated with a large increase atypical memory B cells (MBCs) that resemble expanded variety persistent viral Understanding the function MBCs and their relationship to classical will be critical developing effective vaccines for other chronic We show VH gene repertoires somatic hypermutation rates indistinguishable indicating common developmental history....
Atypical B cells represent an IFN-γ–driven cell lineage that may be similarly expanded in malaria, HIV, and autoimmunity.
Many chronic infections, including malaria and HIV, are associated with a large expansion of CD21-CD27- 'atypical' memory B cells (MBCs) that exhibit reduced cell receptor (BCR) signaling effector functions. Little is known about the conditions or transcriptional regulators driving atypical MBC differentiation. Here we show MBCs in malaria-exposed individuals highly express transcription factor T-bet, T-bet expression correlates inversely BCR skews toward IgG3 class switching. Moreover,...
Abstract Despite the fact that integrin-mediated lymphocyte adhesion is a crucial event for an appropriate immune response, little known about mechanisms control and deadhesion processes generated by engagement of CD99 between various types cells. Here we report gene encodes two distinct proteins with opposite functions in LFA-1/intercellular molecule 1 (ICAM-1)-mediated cell process. The forms protein are produced alternative splicing transcript. major form induced homotypic human B...
Protective antibody responses to vaccination or infection depend on affinity maturation, a process by which high-affinity germinal center (GC) B cells are selected the basis of their ability bind, gather, and present antigen T follicular helper (Tfh) cells. Here, we show that human GC have intrinsically higher-affinity thresholds for both cell receptor (BCR) signaling gathering as compared with naïve these functions mediated distinct cellular structures pathways ultimately lead affinity- Tfh...
The demand for a vaccine coronavirus disease 2019 (COVID-19) highlighted gaps in our understanding of the requirements B cell responses to antigens, particularly membrane-presented as occurs vivo. We found that human antigens required function Piezo1, plasma membrane mechanosensitive cation channel. Simply making contact with glass probe induced calcium (Ca2+) fluxes cells were blocked by Piezo1 inhibitor GsMTx4. When placed on surfaces, tension increased, which stimulated Ca2+ influx and...
Memory B cells (MBCs) play a critical role in protection against homologous and variant pathogen challenge by either differentiating to plasma (PCs) or germinal center (GC) cells. The human MBC compartment contains both switched IgG + unswitched IgM MBCs; however, whether these subpopulations are equivalent their response cell receptor cross-linking resulting fates is incompletely understood. Here, we show that MBCs can be distinguished based on κ-specific monoclonal antibodies of differing...
Atypical memory B cell antigens must be membrane associated to force exclusion of inhibitory receptors from the immune synapse.
B cell responses to membrane-presented antigens appear be strongly favored over soluble in vivo suggesting that vaccines mimic may highly efficacious. We recently demonstrated human membrane-associated but not vitro depended on the expression and activity of plasma membrane mechanosensitive ion channel, Piezo1. Here, we provide evidence efficacy current papillomavirus virus-like particle (HPV VLP) due part their inherent ability Piezo1-dependent presentation cells. compared HPV-specific HPV...
Treatment of L1210 cells with prostaglandin A 2 (PGA ) or 9‐deoxy‐Δ 9,12 ‐13,14‐dihydro PGD (Δ 12 ‐PGJ resulted in significant G2/M arrest and subsequent DNA fragmentation at concentrations that are cytotoxic to the cells. On agarose gel electrophoresis, ladder formation was evident 24 h after addition Δ remained apparent through 72 h, whereas accumulation observed 6 treatment. When morphology examined by electron microscopy, incubated a dose PGA for showed characteristic morphological...
The immune disorder PLAID is found to be the result of destabilization B cell receptor complexes due loss an autoinhibitory domain in phospholipase C–γ2.
Malaria is a deadly infectious disease associated with fundamental changes in the composition of memory B cell (MBC) compartment, most notably large expansion T- bet+ MBCs, termed atypical MBCs. However, we know little about precursors MBCs and conditions that drive their differentiation. We compared responses human tonsil naïve cells, germinal center cells to variety stimulatory conditions. determined persistent antigen presentation presence CpG IFN-γ induced maximal expression T-bet other...
BACKGROUND: Population-based active case-finding (ACF) identifies people with TB in communities but can be costly. METHODS: We conducted an empiric costing study within a door-to-door household ACF campaign urban community Uganda, where all adults, regardless of symptoms, were screened by sputum Xpert Ultra testing. used combination direct observation and self-reported logs to estimate staffing requirements. Study budgets reviewed collect costs overheads, equipment, consumables. Our primary...
In autoimmune diseases, Toll-like receptor (TLR)-stimulated pro-inflammatory IL-6 secreting B cells exert pathogenic roles. Similarly, cell Fc receptor-like 4 (FcRL4) expression amplifies TLR stimulation, and in rheumatoid arthritis patients FcRL4 identifies a subset. from HIV-infected subjects also express heightened levels of secrete high IL-6: critical mediator HIV disease progression. this study we sought to determine if subset further, elucidate the mechanisms underlying amplification...
Abstract During antibody responses to T-dependent antigens B cells undergo clonal expansion and somatic hyper-mutation in the dark zones of germinal centers (GCs) subsequently isotype switching affinity based selection GC light zones. Only a small portion survive from reactions differentiate into either plasma or memory cells. However, mechanism underlying within is not fully understood. We compared behavior human tonsil naïve (IgD+, CD10−) (IgD−, CD10+) as they engaged antigen (using Light...
BACKGROUND: Twelve weeks of weekly isoniazid and rifapentine (3HP) prevents TB disease among people with HIV (PWH), but the costs to taking preventive treatment is not well described. METHODS: We surveyed PWH who initiated 3HP at a large urban HIV/AIDS clinic in Kampala, Uganda, as part larger trial. estimated cost one visit from patient perspective, including both out-of-pocket lost wages. Costs were reported 2021 Ugandan shillings (UGX) US dollars (USD; USD1 = UGX3,587) RESULTS: The survey...