Polymorphisms in TIM-1, a member of the T cell Ig and mucin (TIM) domain family, are associated with relative susceptibility to the development of T helper 2-dominated immune responses such as in allergic asthma. Recent data have also suggested that ligation of TIM-1 can augment T cell activation. We have found that the TIM-1 protein is expressed on CD4 ؉ T cells in vivo after intranasal immunization. Ectopic expression of TIM-1 during T cell differentiation results in a significant increase in the number of cells producing IL-4 but not IFN-␥. Furthermore, TIM-1 expression provides a costimulatory signal that increases transcription from the IL-4 promoter and from isolated nuclear factor of activated T cells͞activating protein-1 (NFAT͞AP-1) elements. Finally, we provide evidence that TIM-1 can be phosphorylated on tyrosine and that TIM-1 costimulation requires its cytoplasmic tail and the conserved tyrosine within that domain. These results constitute evidence that TIM-1 directly couples to phosphotyrosine-dependent intracellular signaling pathways.costimulation ͉ phosphorylation ͉ asthma ͉ cytokines

Vaccines are urgently needed to combat the global coronavirus disease 2019 (COVID-19) pandemic, and testing of candidate vaccines in an appropriate non-human primate (NHP) model is a critical step in the process. Infection of African green monkeys (AGM) with a low passage human isolate of SARS-CoV-2 by aerosol or mucosal exposure resulted in mild clinical infection with a transient decrease in lung tidal volume. Imaging with human clinicalgrade 18 F-fluoro-2-deoxy-D-glucose positron emission tomography (18 F-FDG PET) co-registered with computed tomography (CT) revealed pulmonary lesions at 4 days post-infection (dpi) that resolved over time. Infectious virus was shed from both respiratory and gastrointestinal (GI) tracts in all animals in a biphasic manner, first between 2-7 dpi followed by a recrudescence at 14-21 dpi. Viral RNA (vRNA) was found throughout both respiratory and gastrointestinal systems at necropsy with higher levels of vRNA found within the GI tract tissues. All animals seroconverted simultaneously for IgM and IgG, which has also been documented in human COVID-19 cases. Young AGM represent an species to study mild/ subclinical COVID-19 disease and with possible insights into live virus shedding. Future vaccine evaluation can be performed in AGM with correlates of efficacy being lung lesions by PET/CT, virus shedding, and tissue viral load.

2 Genomic actions involve binding of androgens to ARs, which then translocate to the nucleus, bind to androgen-response elements, and alter gene expression. In contrast, ARs also induce rapid nongenomic signals that are generally mediated by cross-talk between the AR and either G-proteins or growth factor receptors (1-4). Although transcriptional effects of androgens have been extensively studied, mechanisms regulating nongenomic actions of androgens are poorly understood.One potential regulator of nongenomic androgen actions is paxillin. Paxillin is a multidomain adaptor protein that integrates many signals from integrins, cell surface receptors, and growth factors (10, 11). Through these interactions, paxillin regulates a variety of physiological functions, including matrix organization, cell motility, tissue remodeling, metastasis, gene expression, cell survival, and proliferation (10, 11). Paxillin is comprised of multiple structural domains that modulate protein-protein interactions (10) and numerous serine/threonine and tyrosine phosphorylation targets that act as docking sites for various signaling proteins. Phosphorylation of these sites by growth factor receptor-tyrosine kinases, Src kinases, and serine/threonine kinases regulate adaptor molecule binding that ultimately coordinates complex cell signaling pathways (10). The importance of paxillin in normal physiological functions is further evident from global paxillin knock-out studies, demonstrating that ablation of paxillin in mice is embryonic lethal (12,13).We previously demonstrated that in Xenopus oocytes, paxillin is essential for non-genomic androgen-induced Erk signaling and subsequent Erk-mediated oocyte maturation (5). Specifically, paxillin is required for synthesis and activation of MOS (the germ cell Raf homolog), which then promotes MEK and subsequently Erk signaling (5). Interestingly, Erk-mediated phosphorylation of paxillin is also required for androgen-induced oocyte maturation. Thus, in oocytes, paxillin is both an affector and effector of Erk signaling.Here we significantly extend our findings in Xenopus oocytes to a mammalian somatic system. Given the well defined function of androgens and Erk signaling (3, 6 -8) in prostate cancer

Human infections with highly pathogenic avian influenza A (H5N1) virus are frequently fatal but the mechanisms of disease remain ill-defined. H5N1 infection is associated with intense production of proinflammatory cytokines, but whether this cytokine storm is the main cause of fatality or is a consequence of extensive virus replication that itself drives disease remains controversial. Conventional intratracheal inoculation of a liquid suspension of H5N1 influenza virus in nonhuman primates likely results in efficient clearance of virus within the upper respiratory tract and rarely produces severe disease. We reasoned that small particle aerosols of virus would penetrate the lower respiratory tract and blanket alveoli where target cells reside. We show that inhalation of aerosolized H5N1 influenza virus in cynomolgus macaques results in fulminant pneumonia that rapidly progresses to acute respiratory distress syndrome with a fatal outcome reminiscent of human disease. Molecular imaging revealed intense lung inflammation coincident with massive increases in proinflammatory proteins and interferon-α in distal airways. Aerosolized H5N1 exposure decimated alveolar macrophages, which were widely infected and caused marked influx of interstitial macrophages and neutrophils. Extensive infection of alveolar epithelial cells caused apoptosis and leakage of albumin into airways, reflecting loss of epithelial barrier function. These data establish inhalation of aerosolized virus as a critical source of exposure for fatal human infection and reveal that direct viral effects in alveoli mediate H5N1 disease. This new nonhuman primate model will advance vaccine and therapeutic approaches to prevent and treat human disease caused by highly pathogenic avian influenza viruses.

Macrophages and microglia are critical in the acute inflammatory response and act as final effector cells of demyelination during chronic infection with the neutrotropic MHV-JHM strain of mouse hepatitis virus (MHV-JHM). Herein, we show that "immature" F4/80(+)Ly-6C(hi) monocytes are the first cells, along with neutrophils, to enter the MHV-JHM-infected central nervous system (CNS). As the infection progresses, macrophages in the CNS down-regulate expression of Ly-6C and CD62L, consistent with maturation, and a higher frequency express CD11c, a marker for dendritic cells (DCs). Microglia also express CD11c during this phase of the infection. CD11c(+) macrophages in the infected CNS exhibit variable properties of immature antigen-presenting cells (APCs), with modestly increased CD40 and MHC expression, and equivalent potent antigen uptake when compared with CD11c(-) macrophages. Furthermore, CDllc(+) and F4/80(+) macrophages and microglia are localized to areas of demyelination, in some instances directly associated with damaged axons. These results suggest that chronic CNS infection results in the appearance of CD11c-expressing macrophages from the blood that exhibit properties of immature APCs, are closely associated with areas of demyelination, and may act as final effectors of myelin destruction.