Mouse Memory CD8 T Cell Subsets Defined by Tissue-Resident Memory Integrin Expression Exhibit Distinct Metabolic Profiles.

Tissue-resident memory CD8 T cells (TRM) principally reside in peripheral nonlymphoid tissues, such as lung and skin, and confer protection against a variety of illnesses ranging from infections to cancers. The functions of different memory CD8 T cell subsets have been linked with distinct metabolic pathways and differ from other CD8 T cell subsets. For example, skin-derived memory T cells undergo fatty acid oxidation and oxidative phosphorylation to a greater degree than circulating memory and naive cells.

CD49a Identifies Polyfunctional Memory CD8 T Cell Subsets that Persist in the Lungs After Influenza Infection.

CD8 T cell memory offers critical antiviral protection, even in the absence of neutralizing antibodies. The paradigm is that CD8 T cell memory within the lung tissue consists of a mix of circulating T cells and non-circulating T cells. However, based on our analysis, the heterogeneity within the tissue is much higher, identifying T, T, T, and a multitude of populations which do not perfectly fit these classifications.

T integrins CD103 and CD49a differentially support adherence and motility after resolution of influenza virus infection.

Tissue-resident memory CD8 T (T) cells are a unique immune memory subset that develops and remains in peripheral tissues at the site of infection, providing future host resistance upon reexposure to that pathogen. In the pulmonary system, T are identified through S1P antagonist CD69 and expression of integrins CD103/β7 and CD49a/CD29(β1). Contrary to the established role of CD69 on CD8 T cells, the functions of CD103 and CD49a on this population are not well defined.

Formation and Maintenance of Tissue Resident Memory CD8+ T Cells after Viral Infection.

Tissue resident memory (T) CD8 T cells comprise a memory population that forms in peripheral, non-lymphoid tissues after an infection that does not recirculate into the bloodstream or other tissues. T cells often recognize conserved peptide epitopes shared among different strains of a pathogen and so offer a protective role upon secondary encounter with the same or related pathogens. Several recent studies have begun to shed light on the intrinsic and extrinsic factors regulating T.

The Effects of Acute Neutrophil Depletion on Resolution of Acute Influenza Infection, Establishment of Tissue Resident Memory (TRM), and Heterosubtypic Immunity.

After disease resolution, a small subset of influenza specific CD8+ T cells can remain in the airways of the lung as a tissue resident memory population (TRM). These cells are critical for protection from subsequent infections with heterosubtypic influenza viruses. Although it is well established that expression of the collagen IV binding integrin alpha 1 is necessary for the retention and maintenance of TRM cells, other requirements allowing them to localize to the airways and persist are less well understood.

Live Imaging of Influenza Infection of the Trachea Reveals Dynamic Regulation of CD8+ T Cell Motility by Antigen.

During a primary influenza infection, cytotoxic CD8+ T cells need to infiltrate the infected airways and engage virus-infected epithelial cells. The factors that regulate T cell motility in the infected airway tissue are not well known. To more precisely study T cell infiltration of the airways, we developed an experimental model system using the trachea as a site where live imaging can be performed.

NS1 Protein Mutation I64T Affects Interferon Responses and Virulence of Circulating H3N2 Human Influenza A Viruses.

Unlabelled: Influenza NS1 protein is the main viral protein counteracting host innate immune responses, allowing the virus to efficiently replicate in interferon (IFN)-competent systems. In this study, we analyzed NS1 protein variability within influenza A (IAV) H3N2 viruses infecting humans during the 2012-2013 season. We also evaluated the impact of the mutations on the ability of NS1 proteins to inhibit host innate immune responses and general gene expression.

Visualization of integrin Mac-1 in vivo.

β2 integrins play critical roles in migration of immune cells and in the interaction with other cells, pathogens, and the extracellular matrix. Among the β2 integrins, Mac-1 (Macrophage antigen-1), composed of CD11b and CD18, is mainly expressed in innate immune cells and plays a major role in cell migration and trafficking. In order to image Mac-1-expressing cells both in live cells and mouse, we generated a knock-in (KI) mouse strain expressing CD11b conjugated with monomeric yellow fluorescent protein (mYFP).

Neutrophil trails guide influenza-specific CD8⁺ T cells in the airways.

During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells are unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8(+) T cell-mediated immune protection in mice.

Antigenic and immunogenic properties of recombinant hemagglutinin proteins from H1N1 A/Brisbane/59/07 and B/Florida/04/06 when produced in various protein expression systems.

Antibodies directed against the influenza hemagglutinin (HA) protein largely mediate virus neutralization and confer protection against infection. Consequently, many studies and assays of influenza vaccines are focused on HA-specific immune responses. Recombinant HA (rHA) proteins can be produced in a number of protein expression and cell culture systems.

High-risk acute lymphoblastic leukemia cells with bcr-abl and INK4A/ARF mutations retain susceptibility to alloreactive T cells.

INK4A/ARF mutations are acquired in bcr/abl(+) lymphoid blast phase chronic myelogenous leukemia (CML) and bcr/abl(+) acute lymphoblastic leukemia (ALL). Donor lymphocyte infusion and graft-versus-leukemia (GVL) are generally ineffective in such ALLs, whereas GVL is highly active against bcr/abl(+) CML, which does not have a lesion in the INK4A/ARF locus. The mechanisms for the ineffectiveness of GVL are not fully known, and it is possible that intrinsic resistance of acute lymphoid leukemias to immune effectors associated with allogeneic GVL may contribute to ineffectiveness.

Hematopoietic stem cell recipients do not develop post-transplantation immune tolerance to antigens present on minimal residual disease.

The immune environment present after allogeneic hematopoietic stem cell transplantation (HSCT) contributes to the control of leukemia. Our laboratory has demonstrated in a murine model that vaccination of recipients after transplantation with recipient tumor vaccines does not exacerbate graft-versus-host disease but does induce meaningful graft-versus-tumor effects. We previously demonstrated that part of the reason for the lack of graft-versus-host disease from post-transplantation vaccination is due to gradual acquisition of tolerance or unresponsiveness to recipient immunodominant minor histocompatibility antigens that are ubiquitously expressed in the recipient.