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Showing posts from 2012

"How do NK cells know not to kill RBCs?"

I was recently asked about the surveillance system present within immunity which operates to kill virally infected cells by lack of MHC expression, and why this same system doesn't destroy red blood cells (RBC), which lack MHC. One function of Natural Killer (NK) cells is to destroy cells infected by viruses, which have a mechanism of evading T-cell killing by down-regulating MHC class I expression. MHC class I molecules are expressed on every cell in the body apart from RBCs; a lack of expression is detected by NK cells which act to destroy the cell. However, RBC remain unharmed. SEM of NK cells Red Blood Cells                         V.S Like everyone else I assumed the almighty google would provide me with the answer to my friends question, so I typed in my query and the only relevant link was to a 'yahoo answers' page, which answered a succinctly phrased question whi...

Wellcome Collection - BRAINS exhibition

In a moment of rare foresight I decided to spend my 1 hour waiting for a connecting train at Euston station, visiting the latest exhibition on brains at the Wellcome collection . Previously I'd visited the exhibition on skin (unsurprisingly named SKIN ), which served up the right amount of visual and mental stimulation. This latest exhibition proved to be as interesting, but didn't live up to my own hype after the last visit. Security staff greeted me with the deferential smile of 'I'm just doing my job mate', as they politely searched my bag. After being established as benign, I entered through glass doors to be welcomed by an aptly simple title for the show: BRAINS. The familiar blurb preceeding the exhibition provided a prĂ©cis and rationale for the show. The latter, as you can imagine, was due to a lack of understanding by the public and the obvious importance of the brain. I particularly enjoyed the boldness of the neuroscientists sentiment - to prove that per...

Science songs #2: Eels - Novocaine For The Soul

Novocaine, the commercial name for the anaesthetic Procain, has been sung about continually within the 20th century, from Alice Cooper and Bon Jovi, to Modest Mouse and King's of Leon. My favourite testament to the drug is by the UK's Eels, enjoy!

Graft vs. Host

One of the most pressing needs in organ transplantation is the availbility of matched donor material - what this 'matching' specifically means is explained below. Mis-matching of donors and rejection of organs unfortunately happens quite often, and recipients require life long immunosuppressents to dampen the ensuing rejection, or in severe cases a new transplant. The reality and severity of donor mis-matching was clarified recently when  I saw an image of a patient with graft vs host disease (GVHD). In this setting it is the transplanted donor material which attacks/rejects the recipient, rather than the recipient rejecting the donor organ. Previously I had been taught about whole organ GVHD, whereby the transplanted organ harbours immune cells capable of attacking the recipient. This is especially serious when the transplant recipient is immunocompromised. However, the more serious aspect of this disease occurs in patients who...

Ultra rush treatment

Having attended a lecture about the potential benefits of peptide therapy for controlling aberrant immune responses, I was interested to hear about how a radical therapy for curbing allergies could be employed in this treatment. The lecture focused upon peptide immunotherapy as a treatment for curing autoimmunity (i.e. the host immune system attacking itself), this works by providing the individuals immune system with a piece of protein targeted by the response which switches off the destructive process. This mechanism of ignoring self is known broadly as tolerance, in healthy individuals the process of tolerance is successful and occurs around birth, whereas in individuals with autoimmunity 'something' goes wrong. Chinese bee beard competitor People with an autoimmune disease targeting a self protein - like insulin in type 1 diabetes, which results in destruction of beta-cells - have immune cells which have esca...