A pinboard by
Xiaogang Feng

PhD candiacate, Karolinska Institutet


To understand the mechanism of how local infection affect the immune response in the distal sit

Vaccine is commonly used for human preventing from the potential infection. However the efficiency of vaccination differ in populations. With imaging that one vaccine, which works for your family member but not for you only, meaning that you will be more under risk than the others, will you be puzzled or shocked? So you have different genome from the others. It could be correct but consider my advice. I would here suggest you check if you have experienced chronic infection or inflammation, even through you never noticed. We recently have shown the result that mouse with chronic infection has lower BCG (a vaccine to against mycobacteria tuberculosis) efficiency compare to the mice without infection even those two mice have same parents. What is the reason behind it? We might get clue from this scientific story. A number of immunocytes, which is comprised of your body defence system; function as “soldiers cell” surveillance in your body. They normally circulate evenly along your body for checking the new invading pathogen---“stranger” and kill them. Once meet to the new stranger, the soldier cell will try to get rid of it and more soldiers cell also come and helps for killing. However, the recruitment of soldiers cell lead to the temporary “unregulated zone” in other part of the body, which then expose the body under the risk. Vaccine, worked as a purposed stranger, on the other hand attracts and trains a number of “soldiers cell” to properly kill the stranger and memory that killing them when meet the same stranger next time. However, prior to the vaccine emerging, another stranger invade your body and attract rather big population of “soldier cell” to fight with them. Your “unregulated zone” then only has few soldier cells to be attracted and trained by this vaccine. So the unexpected result will be either your body is under the risk by vaccine or the soldier cell could not well trained or “enough-trained” so that they can not protect you once the same stranger with severe destruction ability come to you. You may already know what chronic infection is. It is triggered by invading worm or bacteria which co-habitat in your body for long term. They exhausted your body and keep attracting your soldier cell and expose your other part body to the risk, which also make your vaccine become effectiveness. Vaccine work for you or not? Maybe depend on if you are “visited” by worm or bacteria. Get rid of them and then try the vaccine again!