Showing posts with label bacteria. Show all posts
Showing posts with label bacteria. Show all posts

Saturday, July 29, 2017

FASTER WAY TO PRODUCE SPECIFIC HUMAN ANTIBODIES USING NANOPARTICLES

Treating patient derived B cells with nanoparticles coated with CpG oligonucleotides to stimulate plasma cell production and challenge antigens to designate what kind of antibody the B cells should produce has resulted in the generation of specific, high affinity antibodies in just a few days that can recognize several strains of a pathogen at the same time. The researchers have already produced antibodies to a variety of bacterial and viral antigens, including tetanus toxoid and several strains of influenza, and were able to generate anti HIV antibodies from B cells donated by healthy volunteers who did not have the disease.

The new technique also eliminates the need for previous exposure to the pathogens, either by vaccination or infection.

"Our technique should allow the production of these antibodies within a shorter time frame in vitro and without the need for vaccination or blood/serum donation from recently infected or vaccinated individuals," said Dr. Facundo Batista, who led the team from the Francis Crick Institute in London, the Ragon Institute of Massachusetts General Hospital, MIT and Harvard. "In addition, our method offers the potential to accelerate the development of new vaccines by allowing the efficient evaluation of candidate target antigens."

Antibodies are produced by white blood cells called B cells, which recognize the calling card of a bacteria or virus called an antigen, and transform into plasma cells tailored to produce large numbers of antibodies to that specific antigen that fight off the disease. That's what happens in the body. When scientists tried to reproduce the process in the lab, they ran into problems getting the B cells to make the specific kind of plasma cells they needed because the challenge antigens were missing.



It was easy to get the B cells to proliferate by adding short DNA fragments called CpG oligonucleotides into their culture medium. CpG oligonucleotides activate a protein inside B cells TLR9, but TLR9 enthusiastically stimulates every B cell in the sample to respond, not just the tiny fraction capable of producing a particular antibody. Batista and his colleagues attached both CpG oligonucleotides and real challenge antigens to nanoparticles, added them to B cell cultures, and the plasma cells that resulted were both abundant and pathogen specific.

The team hopes their approach will help researchers produce therapeutic antibodies to treat infectious disease and other conditions, such as cancer.

For more information, go to the Journal of Experimental Medicine
http://jem.rupress.org/cgi/doi/10.1084/jem.20170633?PR
https://www.eurekalert.org/pub_releases/2017-07/rup-rdn071717.php

Wednesday, October 12, 2016

Autophagy genes are discovered by Yoshinori Ohsumi for the greatest benefit to mankind

Autophagy has been known for over 50 years but its fundamental importance in physiology and medicine was only recognized after Yoshinori Ohsumi's paradigm-shifting research in the 1990's.

The experiment by 2016 Medicine Laureate Yoshinori Ohsumi demonstrated that autophagy exists in yeast. Ohsumi studied thousands of yeast mutants and identified 15 genes that are essential for autophagy. But even more importantly, he now had a method to identify and characterize key genes involved in this process. This was a major break through and Ohsumi published the results in 1992. First key publication: Takeshige, K., Baba, M., Tsuboi, S., Noda, T, and Ohsumi, Y. (1992). Autophagy in yeast demonstrated with proteinase-defifient mutants and conditoins for its induction. Journal of Cell Biology 119, 301-3011

The term "autophagy" was coined by Christian de Duve in 1963. Our bodies are made up of cells that contain organelles, components with various functions, Albert Claude's research with the newly developed electron microscope and his methods for separating the various parts of pulverized cells using a centrifuge opened up new opportunities for studying cells in detail. In 1995, Christian de Duve discovered previously unknown organelles in the cell, lysosomes. These have important functions in decomposing different types of materials, such as bacteria and parts of cells that have worn out. In 1974 de Duve shared the Nobel Prize in Medicine for discovering the lysosome.

Thanks to Ohsumi and others following in his footsteps, we now know that autophagy controls important physiological functions where cellular components need to be degraded and recycled. Autophagy can rapidly provide fuel for energy and building blocks for renewal of cellular components, and is therefore essential for the cellular response to starvation and other types of stress. After infection, autophagy can eliminate invading intracellular bacteria and viruses. Autophagy contributes to embryo development and cell differentiation. Cells also use autophagy to eliminate damaged proteins and organelles, a quality control mechanism that is critical for counteracting the negative consequences of aging.

Disrupted autophagy has been linked to Parkinson's disease, type 2 diabetes and other disorders that appear in the elderly. Mutations in autophagy genes can cause genetic disease. Disturbances in the autophagic machinery have also been linked to cancer. Intense research is now ongoing to develop drugs that can target autophagy in various diseases.

Tuesday, December 7, 2010

Bacteria*Bioengineering*Storage

A new method of data storage that converts information into DNA sequences allows you to store the contents of an entire computer hard-drive on a gram's worth of E coli and perhaps considerably more than that.

Source:

Thursday, February 26, 2009

Gram positive bacteria
aerobic coccus- Staphylococcus, Streptococcus, Enterococcus
anaerobic coccus- Peptostreptococcus

aerobic / facultative anaerobic rod- Bacillus, Corynebacterium, Lactobacillus, Mycobacterium, Listeria, Nocardia
anaerobic rod- Clostridium, Actinomyces

Gram negative bacteria
aerobic coccus- Neisseria

aerobic rod- Pseudomonas
facultative anaerobic rod- Escherichis, Proteus, Klebsiella, Shigella, Salmonella, Vibrio, Haemophilus, Bordetella, Brucella, Yersinia, Pasteurella
anaerobic rod- Bacteroid, Fusobacterium
Microaerophilic rod- Campylobacter

aerobic spirochaete- LeptospiraMycobacterium Avium-complex Infection (Lung Biology in Health and Disease)Mycobacterium: Genomics and Molecular Biology
anaerobic spirochaete- Borrelia, Treponema
Quorum Sensing: Bacteria, Gene Expression, Eusociality, Species, Molecule, Signal, Oligopeptide, Gram-Positive Bacteria, N-Acyl Homoserine Lactone, Gram-Negative Bacteria