Discovery of New White Blood Cell Reveals Target for Better Vaccine Design

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ScienceDaily (July 27, 2012) — Researchers in Newcastle and Singapore have identified a new type of white blood cell which activates a killing immune response to an external source -- providing a new potential target for vaccines for conditions such as cancer or Hepatitis B.
Publishing in the journal Immunity, the team of researchers from Newcastle University in collaboration with A*STAR's Singapore Immunology Network (SIgN) describe a new human tissue dendritic cell with cross-presenting function.
Dendritic cells (DCs) are a type of white blood cell that orchestrate our body's immune responses to infectious agents such as bacteria and viruses, as well as cancer cells. They are also very important for eliciting the immune response generated by vaccines.
DCs kick start an immune response by presenting small fragments of molecules from micro-organisms such as bacteria and viruses, or from vaccines or tumours, called antigens on their surface. This leads to activation of another white blood cell subset called T cells, which specialise in killing cells and are crucial for eliminating cancerous or infected cells. Most cells are only able to present antigens from within themselves, and so will only elicit an immune response if they are infected themselves. Only a specialised subset of DCs is able to generate a response to an external source of antigen, for example bacteria, vaccines and tumours.
The identity of human tissue DCs that are capable of presenting external antigen to activate the cell-killing response by T cells -- a process termed 'cross-presentation' -- has remained a mystery. Their discovery, as revealed by this research, will help scientists to design better targeted vaccine strategies to treat cancer and infections such as Hepatitis B.
"These are the cells we need to be targeting for anti-cancer vaccines," said Dr Muzlifah Haniffa, a Wellcome Trust Intermediate Fellow and Senior Clinical Lecturer at Newcastle University. "Our discovery offers an accessible, easily targetable system which makes the most of the natural ability of the cell." The researchers also showed for the first time that dendritic cell subsets are conserved between species and have in effect created a map, facilitating the translation of mouse studies to the human immune system.
"The cross-species map is in effect a Rosetta stone that deciphers the language of mouse into human," explains Matthew Collin, Professor of Haematology from Newcastle University.
In the paper the researchers describe how the cross-presenting DCs were first isolated from surplus plastic surgery skin which was digested to melt the gelatinous collagen to isolate the cells. This research will have significant impact on the design of vaccines and other targeted immunotherapies.
The Rosetta Stone of our immune system: Mapping Human and Mouse dendritic cells
The Newcastle University team in collaboration with A*STAR's Singapore Immunology Network (SIgN) have for the first time ever aligned the dendritic cell subsets between mouse and humans allowing the accurate translation of mouse studies into the human model for the first time.
The researchers isolated the dendritic cells from human blood and skin and those from mouse blood, lung and liver. Using gene expression analysis, they identified gene signatures for each human dendritic cell subset. Mouse orthologues of these genes were identified and a computational analysis was performed to match subsets across species.
This provides scientists for the first time with an accurate model to compare DCs between species. Professor Matthew Collin explains: "This is in effect a Rosetta stone that deciphers the language of mouse into human. It can put into context the findings from the extensive literature using mouse models to the human settings."
Dr. Haniffa added: "These gene signatures are available in a public repository accessible for all researchers to benefit from the data. It will allow detailed knowledge of individual human dendritic cell subsets to enable specific targeting of these cells for therapeutic strategy."
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Google unveils world’s fastest net connection


ONDON: Internet giant Google has unveiled what it says is the world's fastest internet connection through its ultrahigh-speed service, offering lightning-fast access of one gigabit per second.
The service which uses optical fibre to deliver speeds far in excess of traditional web services, offering speeds faster than almost anywhere else on Earth.
The web search leader unveiled its ultra-high speed Google Fiber service in Kansas City, Missouri, and it hopes to roll out the service to other cities later, the Daily Mail reported.
"Access is the next frontier that needs to be opened, we're going to do it profitably. That is our plan," Google chief financial officer Patrick Pichette said. "We are at a crossroad," he added, noting that internet speeds had leveled out for broadband since around 2000. We at Google believe there is no need to wait," he said.
Google Fiber's ultra highspeed connections and television offerings are aimed at surpassing those of current providers, allowing users to search live channels, Netflix, YouTube, recorded shows and tens of thousands of hours of on-demand programming . However, no phone service is available.
Google said it also intends to roll out product packages for businesses, but would not provide details.
Google Fiber includes more than 100 networks and costs $120 a month for a package of TV, 1 gigabit per second Internet speeds and 1 terabyte of cloud storage.


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CO2 Capture from Atmospheric Air Necessary to Address Global Warming

Published on July 25, 2012 at 7:42 AM
By Gary Thomas

Researchers from the Georgia Institute of Technology have shown the economic and chemical feasibility for extracting CO2 directly from air. They utilized new adsorbent materials in the novel method to capture CO2.

Stephanie Didas, a Georgia Tech Ph.D. candidate, loads an aminosilica sample into a custom-built volumetric adsorption system for measuring adsorption isotherms of different carbon dioxide capture materials. Credit: Gary Meek
The technique may also be used to capture CO2 from power plant flue gases. The captured CO2 may be used for improving oil recovery and for producing fuel from algae.
Coal-burning power plants and chemical facilities contribute to less than 50% of the global CO2 emissions. Transport vehicles such as planes, ships, trucks and buses account for the rest of the emissions and capturing these emissions are comparatively more expensive. According to the researchers, the operating costs involved were approximately $100 per ton when using a large CO2 removal unit that has the capacity to remove 1000 ton of CO2 per annum. Removal of CO2 from flue gas alone will not help address the global CO2 emissions. Air capture is required.
The atmosphere contains 400 ppm of CO2 while flue gases contain about 15%. The difference in capture efficiency and economic feasibility can be addressed by establishing CO2 removal units at sequestration locations.
The Georgia Tech researchers have modeled a batch extraction process that demonstrates economic feasibility. Dry amino-modified silica material is coated onto a ceramic honeycomb structure. The air is blown through the structure and the material captures the gas. Later steam is flown through the structure in order to release the gas.
The researchers have been conducting studies on metal-organic framework materials and have published papers in Journal of the American Chemical Society, ChemSusChem, and Industrial & Engineering Chemistry Research on alternate adsorbent materials.
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