AuthorsPythoud C, Rodrigo WW, Pasqual G, Rothenberger S, Martínez-Sobrido L, de la Torre JC, Kunz S,
JournalJ Virol
PubMed ID22532683
'Arenaviruses perturb innate antiviral defense by blocking induction of type I interferon (IFN) production. Accordingly, the arenavirus nucleoprotein (NP) was shown to block activation and nuclear translocation of interferon regulatory factor 3 (IRF3) in response to virus infection. Here, we sought to identify cellular factors involved in innate antiviral signaling ... More
In vivo expansion of T reg cells with IL-2-mAb complexes: induction of resistance to EAE and long-term acceptance of islet allografts without immunosuppression.
AuthorsWebster KE, Walters S, Kohler RE, Mrkvan T, Boyman O, Surh CD, Grey ST, Sprent J,
JournalJ Exp Med
PubMed ID19332874
'Via a transcription factor, Foxp3, immunoregulatory CD4(+)CD25(+) T cells (T reg cells) play an important role in suppressing the function of other T cells. Adoptively transferring high numbers of T reg cells can reduce the intensity of the immune response, thereby providing an attractive prospect for inducing tolerance. Extending our ... More
Rapid lytic granule convergence to the MTOC in natural killer cells is dependent on dynein but not cytolytic commitment.
AuthorsMentlik AN, Sanborn KB, Holzbaur EL, Orange JS,
JournalMol Biol Cell
PubMed ID20444980
'Natural killer cells are lymphocytes specialized to participate in host defense through their innate ability to mediate cytotoxicity by secreting the contents of preformed secretory lysosomes (lytic granules) directly onto a target cell. This form of directed secretion requires the formation of an immunological synapse and occurs stepwise with actin ... More
Immunosuppressive property within the Streptococcus pneumoniae cell wall that inhibits generation of T follicular helper, germinal center, and plasma cell response to a coimmunized heterologous protein.
'We previously demonstrated that intact, inactivated Streptococcus pneumoniae (unencapsulated strain R36A) inhibits IgG responses to a number of coimmunized soluble antigens (Ags). In this study, we investigated the mechanism of this inhibition and whether other extracellular bacteria exhibited similar effects. No inhibition was observed if R36A was given 24 h ... More
Thymocytes may persist and differentiate without any input from bone marrow progenitors.
AuthorsPeaudecerf L, Lemos S, Galgano A, Krenn G, Vasseur F, Di Santo JP, Ezine S, Rocha B,
JournalJ Exp Med
PubMed ID22778388
'Thymus transplants can correct deficiencies of the thymus epithelium caused by the complete DiGeorge syndrome or FOXN1 mutations. However, thymus transplants were never used to correct T cell-intrinsic deficiencies because it is generally believed that thymocytes have short intrinsic lifespans. This notion is based on thymus transplantation experiments where it ... More
JAM-B regulates maintenance of hematopoietic stem cells in the bone marrow.
AuthorsArcangeli ML, Frontera V, Bardin F, Obrados E, Adams S, Chabannon C, Schiff C, Mancini SJ, Adams RH, Aurrand-Lions M,
JournalBlood
PubMed ID21868569
In adult mammals, hematopoietic stem cells (HSCs) reside in the bone marrow (BM) and are maintained in a quiescent and undifferentiated state through adhesive interactions with specialized microenvironmental niches. Although junctional adhesion molecule-C (JAM-C) is expressed by HSCs, its function in adult hematopoiesis remains elusive. Here, we show that HSCs ... More
Rapid activation receptor- or IL-2-induced lytic granule convergence in human natural killer cells requires Src, but not downstream signaling.
Natural killer (NK) cells participate in host defense by surveying for and ultimately killing virally infected or malignant target cells. NK cell cytotoxicity is a tightly regulated process that proceeds stepwise from adhesion and activation to the secretion of preformed lytic granule contents onto a diseased or stressed cell. We ... More
Quantifying viable virus-specific T cells without a priori knowledge of fine epitope specificity.
AuthorsBeadling C, Slifka MK
JournalNat Med
PubMed ID17013384
Identification of pathogen-specific T cells has been greatly facilitated by the advent of synthetic peptide-major histocompatibility complex (MHC) tetramers. In many cases, however, specific epitopes have not been defined, necessitating detection methods that function independently of exact peptide-MHC specificity. Lymphocytes acquire surface proteins from antigen-presenting cells (APCs), and we have ... More