chapter 2

so wat happens next..
- 02.00 hrs, crisis: intense fighting continues in the lung between the invaders and the cops (leucocytes).. much damage has been done to the lung tissue. this is when the feds arrive. these r lymphocytes and i call them feds for a no. of reasons..
these cells arrive at the lungs.. they meet the sherif (the lung's local force). these guys usually catch some of the invaders by gobbling them up and digestin them. they present remnants of the same to the feds.. the invaders r identified . the feds consist two types of forces.. the T cells and the B cells.. which r coordinated by the Helper T cell (HT). the HT identifies the invader and activates and coordinates a well orchestrated plan to eliminate the villians..
-02:45 hrs, T cells upon recievin signals from HT rush to the lung with the available force while sendin signals to the bone marrow (the fed academy) to send more troops. the T cells have less firepower when compared to the leucocytes but they dont do much damage to the lung tissue. and they can build up a larger force and contain the virus.
- 03:30hrs, B cells.. when activated.. produce immunoglobulins, popularly called antibodies... these r essential for capture of the viruses that have entered the circulation. these chaps r releasd in the millions into the bloodstream and when they come across a virus or a cell held hostage by one.. they stick onto them. this creates a signal which arouses the curiosity of patrolling leucocytes who come and finish up the intruder. the antibodies also directly attack the viruses at the lungs though their role is small in the tissue..
- In the end, this kinda attack can be vanquished effectively.. but in some cases like influenza or a weak host defence can lead to multiplication and spread of the invaders to other areas of the lung and even other parts of the body.. in some cases like tuberculosis, the bacteria can hide inside lung's own defence cells.. for quite long periods and when host defence weakens.. they wake up and do extensive damage.
lastly, the Helper T cells r THE most important defence cells.. not only do they coordinate the attack but they keep a memory bank of all the villians who have enetered so far.. the second timers r crushed even before they know it..
Unfortunately, the HIV virus attacks the helper T cells and makes them more or less useless..one by one they r killed until there r too few. so even a relatively easy group of thugs (bacteria) can do much damage..
well thats just a glimpse of this beautifully designed system.. there is so much more detail to it but thats not for now.