Potential killers exposed: tracking endogenous influenza-specific CD8 T cells.

Current influenza A virus (IAV) vaccines stimulate antibody responses that are directed against variable regions of the virus, and are therefore ineffective against divergent strains. As CD8 T cells target the highly conserved, internal IAV proteins, they have the potential to increase heterosubtypic immunity. Early T-cell priming events influence lasting memory, which is required for long-term protection.

Paired analysis of TCRα and TCRβ chains at the single-cell level in mice.

Characterizing the TCRα and TCRβ chains expressed by T cells responding to a given pathogen or underlying autoimmunity helps in the development of vaccines and immunotherapies, respectively. However, our understanding of complementary TCRα and TCRβ chain utilization is very limited for pathogen- and autoantigen-induced immunity. To address this problem, we have developed a multiplex nested RT-PCR method for the simultaneous amplification of transcripts encoding the TCRα and TCRβ chains from single cells.

Physiological numbers of CD4+ T cells generate weak recall responses following influenza virus challenge.

Naive and recall CD4(+) T cell responses were probed with recombinant influenza A viruses incorporating the OVA OT-II peptide. The extent of OT-II-specific CD4(+) T cell expansion was greater following primary exposure, with secondary challenge achieving no significant increase in numbers, despite higher precursor frequencies. Adoptive transfer experiments with OT-II TCR-transgenic T cells established that the predominant memory set is CD62L(hi), whereas the CD62L(lo) precursors make little contribution to the recall response.

The intracellular sensor NLRP3 mediates key innate and healing responses to influenza A virus via the regulation of caspase-1.

Virus-induced interlukin-1beta (IL-1beta) and IL-18 production in macrophages are mediated via caspase-1 pathway. Multiple microbial components, including viral RNA, are thought to trigger assembly of the cryopyrin inflammasome resulting in caspase-1 activation. Here, we demonstrated that Nlrp3(-/-) and Casp1(-/-) mice were more susceptible than wild-type mice after infection with a pathogenic influenza A virus.

TNF/iNOS-producing dendritic cells are the necessary evil of lethal influenza virus infection.

Respiratory infection with highly pathogenic influenza A viruses is characterized by the exuberant production of cytokines and chemokines and the enhanced recruitment of innate inflammatory cells. Here, we show that challenging mice with virulent influenza A viruses, including currently circulating H5N1 strains, causes the increased selective accumulation of a particular dendritic cell subset, the tipDCs, in the pneumonic airways. These tipDCs are required for the further proliferation of influenza-specific CD8(+) T cells in the infected lung, because blocking their recruitment in CCR2(-/-) mice decreases the numbers of CD8(+) effectors and ultimately compromises virus clearance.

Screening monoclonal antibodies for cross-reactivity in the ferret model of influenza infection.

Influenza virus infections carry a high public health cost, and pandemics are potentially catastrophic. Though the ferret is generally regarded as the best model for human influenza, few reagents are available for the analysis of cellular immunity. We thus screened monoclonal antibodies (mAbs) made for identifying immune cells in other species to see if any were cross-reactive.

DLL3 as a candidate gene for vertebral malformations.

Investigations have not identified a major locus for congenital vertebral malformations. Based on observations in mice, we hypothesized that mutations in DLL3, a member of the notch-signaling pathway, might contribute to human vertebral malformations. We sequenced the DLL3 gene in 50 patients with congenital vertebral malformations.

Efficacy of the influenza vaccine in patients with malignant lymphoma.

Background: The benefits and efficacy of the influenza vaccine have been controversial and have had mixed reviews in the recent literature. Immunosuppressed patients and those receiving chemotherapy are particularly at risk for infectious complications and are therefore given high priority to receiving prophylactic vaccines.

Method: We administered the influenza vaccine to 29 patients with malignant lymphoma who were receiving chemotherapy or had recently completed therapy during the flu season of 2003-2004.

Identification of mosquito bloodmeal source by terminal restriction fragment length polymorphism profile analysis of the cytochrome B gene.

Previous studies have shown that polymerase chain reaction (PCR) heteroduplex analysis (HDA) of the cytochrome B (cytb) gene is useful in identifying mosquito bloodmeals derived from avian hosts. However, interpretation of PCR-HDA gels is performed visually, which can make it difficult to analyze large numbers of specimens and to compare results between laboratories. We investigated the utility of a terminal restriction fragment length polymorphism (T-RFLP) assay to analyze cytb PCR products.

Rapid molecular diagnosis of lactobacillus bacteremia by terminal restriction fragment length polymorphism analysis of the 16S rRNA gene.

Objective: Bacteremia due to lactobacilli is uncommon, yet it is increasing in frequency, especially among immunosuppressed patients. In the clinical laboratory, lactobacilli must be subcultured from positive blood cultures before identification by traditional biochemical methods. Delays in diagnosis are significant because the organisms are inherently resistant to vancomycin, a drug frequently prescribed for empiric therapy for gram-positive bacteremia.

Congenital and idiopathic scoliosis: clinical and genetic aspects.

Objective: Genetic and environmental factors influencing spinal development in lower vertebrates are likely to play a role in the abnormalities associated with human congenital scoliosis (CS) and idiopathic scoliosis (IS). An overview of the molecular embryology of spinal development and the clinical and genetic aspects of CS and IS are presented. Utilizing synteny analysis of the mouse and human genetic databases, likely candidate genes for human CS and IS were identified.

Current diagnosis and treatment of infective endocarditis.

The incidence of infective endocarditis continues to rise with a yearly incidence of around 15,000 to 20,000 new cases in the USA. As a result, rapid diagnosis, effective treatment and prompt recognition of complications are essential to desirable clinical outcomes. Recent guidelines such as the Duke criteria have incorporated echocardiography for diagnosis of infective endocarditis, making this diagnostic test mandatory for patients with suspected infective endocarditis.