immunologe

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Proteus OX19 and the Polish Schindler,

Proteus OX19 is a strain of the bacterium Proteus vulgaris, a simple gram negative bacteria that is commonly found in dirt and water.  It is a fairly unremarkable bacteria, some exposed to it might suffer urinary tract infections or infections of wounds.  However, most infected with the bacteria will suffer few symptoms as the body’s immune system eradicates the invading microbe.  It does have one interesting reaction, however.  People exposed to Proteus OX19 often test false positive for typhus, a disease which is much deadlier and can cause terrible outbreaks and epidemics.

When Germany invaded Poland on Sept. 1st, 1939, Dr. Eugeniusz Lazowski served as an army doctor with the Polish Army.  After the occupation of Poland by Germany, Dr. Lazowski returned home to Rozwadow to continue his private medical practice.  However, he heard news of mass deportations of Poles and Jews by the Nazi’s.  Hundreds of thousands of Jews were being rounded up and deported to concentration camps.  Hundreds of thousands of Poles were also being deported to Germany as forced labor.  It was only a matter of time before the Germans demanded the deportation of Poles from Rozwadow, and Lazowski was determined that the Nazi’s would go empty handed.

Lazowski solution was ingenious and audacious; to keep the Germans away from Rozwadow by simulating a fake typhus epidemic. At the time, Germany was terrified of the prospect of a typhus outbreak spreading across the Fatherland, and strict protocols were in place to isolate and quarantine infected areas.  Inspired by the Proteus microbe, Lazowski informed German medical officials that Rozwadow was being ravaged by a terrible typhus epidemic.  With the help of his friend, Dr Stanisław Matulewicz, Dr. Lazowski injected the people of Rozwadow with proteus OX19, as well as the residents of several nearby Jewish ghettos, so that they would all test false positive for typhus.  He then sent blood samples to German medical officials.  As predicted, the samples all tested false positive for typhus.

In response, the Germans sent three medical inspectors to assess the seriousness of the epidemic.  The three inspectors were greeted cordially and plied with food and generous amounts of vodka.  They were then given a short tour of the town.  Due to fears of contracting the disease, the Germans only made a cursory examination of the town.  Then they were led to a fake medical ward filled with severely ill patients.  Dr. Lazowski claimed they were suffering from typhus, and again due to the German’s fear of contracting the disease, they made no medical assessments.  Instead they took Dr. Lazowski at his word and sped out of Razwadow, declaring the town and surrounding area to be in a state of quarantine.  Little did they know, the so called “patients” the German’s were led to were people with flu and pneumonia, told to act as sick as possible.

Due to the quarantine, the Germans never deported anyone from Razwadow or the ghettos.  As a result, he is credited with saving 8,000 Jews from certain death, and thousands of other Poles from deportation.  Throughout the rest of the war he lent his medical services to the Polish resistance, and worked to smuggle Jews to safety from the Nazi’s.  After the war he moved to the United States and worked as a pediatrician.  He died in 2006 at the age of 96.

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Here’s some stunning video of your immune cells doing their thing. 

Every so often, your body’s own cells become dangerous to you. When that happens, cytotoxic T cells (also known as T killer cells) are your immune system’s way of dealing with the threat. 

More often than not, they succeed in vanquishing cells that have become infected with viruses or mutated to the point of becoming cancerous before they can cause further trouble. 

To accomplish this, they’re armed with a battery of chemical weapons and enzymes that they can use to cause target cells to burst open in the event known as lysis. 

Examine the image captions for some more information on what you’re looking at in each one. 

I produced these gifs from some of the latest microscope footage to come out of the National Institutes of Health. Check out the source of this post for some more detailed information and video. It’s pretty amazing how small these things are; ten of them could fit end-to-end across the tip of a human hair. 

3:07pm: needed a change of scenery so I moved down to the kitchen for the afternoon; it’s a bit chilly, but it’ll do. Things are going okay — not really well but ‘okay’. Still stressed about my exams and I still don’t think I’ll do the best I could do, which is annoying, but really, I just want to pass and for these exams to be over. Revising this much material almost non-stop for 4 whole weeks, is very exhausting. Don’t try it kids.

I hate studying on Saturday :(

Note: I use the notebook on the left for taking some notes during lessons (but I usually use iPad), the notebook on the right is for studying at home!

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Overview of the Immune System

7 reasons why cancer cells are immortal

1. Cancer cells don’t age.
Normal cells go through senescence through shortening of telomeres with every cell division. Cancer cells however have telomerase that will sustain the telomere length of the chromosomes rendering the cell virtually immortal.

2. Cancer cells have a way around apoptosis, their programmed cell death.
They overexpress antiapoptotic molecules and can multiply forever.

3. The Grim Reaper can’t recognize them.
The Natural killer cells, or the Grim Reaper; are supposed to cause death of the tumor cells. However, cancer cells remain undetected because they down regulate their MHC proteins or use decoy proteins to look innocent.

4. If recognized, the Grim Reaper can’t kill them.
Tumor cells block the death receptor pathway and directly interfere with the perforin/granzyme pathway. That is why, natural killer cells fail to kill them.

5. Cancer cells don’t need anything.
Cancer cells are self sufficient on growth factors. This means that they can continue to proliferate and divide independently, as opposed to normal cells that need external growth factors.

6. And if they do need something, they order it to come to them.
When cancer cells need of oxygen and nutrients, they stimulate angiogenesis; which is inducing growth of new blood vessels.

7. They have metabolic super powers.
The metabolism of malignant cells is usually more anaerobic than that of normal cells and is greatly accelerated. Malignant cells have the ability to withstand hypoxic conditions. They have increased glucose and amino acid uptake. In addition, they have high levels of hexokinase increasing their glucose utilization.

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Why You Are Still Alive - The Immune System Explained by Kurzgesagt.