Potential Hydrodynamic Cytoplasmic Transfer between Mammalian Cells: Cell-Projection Pumping.

We earlier reported cytoplasmic fluorescence exchange between cultured human fibroblasts (Fibs) and malignant cells (MCs). Others report similar transfer via either tunneling nanotubes (TNTs) or shed membrane vesicles, and this changes the phenotype of recipient cells. Our time-lapse microscopy showed most exchange was from Fibs into MCs, with less in the reverse direction.

Seasoned adaptive antibody immunity for highly pathogenic pandemic influenza in humans.

Fundamentally new approaches are required for the development of vaccines to pre-empt and protect against emerging and pandemic influenzas. Current strategies involve post-emergent homotypic vaccines that are modelled upon select circulating 'seasonal' influenzas, but cannot induce cross-strain protection against newly evolved or zoonotically introduced highly pathogenic influenza (HPI). Avian H5N1 and the less-lethal 2009 H1N1 and their reassortants loom as candidates to seed a future HPI pandemic.

Vascularity during wound maturation correlates with fragmentation of serum albumin but not ceruloplasmin, transferrin, or haptoglobin.

Reduced vascularity during wound maturation is mediated by endothelial apoptosis. Albumin has an anti-apoptotic activity for endothelium, which increases up to 100-fold on albumin fragmentation (AF). We now report that levels of AF correlate with changing vascularity during wound maturation.

Heterosubtypic anti-avian H5N1 influenza antibodies in intravenous immunoglobulins from globally separate populations protect against H5N1 infection in cell culture.

With antigenically novel epidemic and pandemic influenza strains persistently on the horizon it is of fundamental importance that we understand whether heterosubtypic antibodies gained from exposures to circulating human influenzas exist and can protect against emerging novel strains. Our studies of IVIG obtained from an infection-naive population (Australian) enabled us to reveal heterosubtypic influenza antibodies that cross react with H5N1. We now expand those findings for an Australian donor population to include IVIG formulations from a variety of northern hemisphere populations.

Acquired heterosubtypic antibodies in human immunity for avian H5N1 influenza.

Well understood are the adaptive and dramatic neutralizing homosubtypic antibody responses to hypervariable, immunodominant sites of the hemagglutinin (HA) and neuraminidase (NA) of individual influenza strains. These define influenza subtypes and vaccines modelled upon their HA and NA antigens provide seasonal neutralizing antibody protection against subsequent exposure to the strain and its close relatives, but give little if any protection against antigenically drifted or shifted strains. Contrasting to this is a different form of acquired antibody response, called heterosubtypic immunity.

A commercial ELISA detects high levels of human H5 antibody but cross-reacts with influenza A antibodies.

Background And Objectives: Commercial serological assays to determine influenza A H5N1 infection are available, although the accuracy and reproducibility of these are not reported in detail. This study aimed to assess the validity of a commercial ELISA H5 hemagglutinin (HA) antibody kit.

Study Design: A commercial ELISA for detection of antibodies towards influenza A H5 HA was evaluated using human sera from vaccinated individuals.

Comparison of human platelet membrane-cytoskeletal proteins with the plasma proteome: Towards understanding the platelet-plasma nexus.

Platelets are essential for maintaining vascular integrity. Given the anucleate nature of platelets, definition of their proteome is essential for understanding platelet pathophysiology. We describe here a detailed MS-based proteomic analysis of the platelet membrane/cytoskeletal sub-proteome from purified, normal, non-activated human platelets.

Marked differences in the structures and protein associations of lymphocyte and monocyte CD4: resolution of a novel CD4 isoform.

The structures, molecular interactions and functions of CD4 in a subset of T lymphocytes have been well characterized. The CD4 receptors of other cell types have, however, been poorly documented. We have previously shown that lymphocytes and monocytes/macrophages differ in their expression of CD4 monomers and dimers.

Marked structural and functional heterogeneity in CXCR4: separation of HIV-1 and SDF-1alpha responses.

CXCR4, the chemotactic cell receptor for SDF-1alpha, is essential for immune trafficking and HIV infection. CXCR4 is remarkably heterogeneous and the purpose of this study was to better identify the isoforms expressed by cells and compare their structure and function. We found that cells express either a predominant isoform or multiple isoforms.

Detergent-resistant membrane fractions contribute to the total 1H NMR-visible lipid signal in cells.

Leukocytes and other cells show an enhanced intensity of mobile lipid in their 1H NMR spectra under a variety of conditions. Such conditions include stimulation, which has recently been shown to involve detergent-resistant, plasma membrane domains (DRMs) often called lipid rafts. As there is much speculation surrounding the origin of cellular NMR-visible lipid, we analysed subcellular fractions, including DRMs, by NMR spectroscopy.