why avidity decreases as affinity increases ?? - bhuvana

[ArchivalUser]

can someone explain please...

[ArchivalUser]

go to...




http://64.233.167.104/search?q=cache:f6d...=clnk&cd=1

[ArchivalUser]

thanks a lot sandoc77

[ArchivalUser]

Bhuvana does it explain why avidity decreases when affinity increases, and where did u find this question or statement?
thanks a lot.

[ArchivalUser]

check this out , for avidity, think of it as high number of binding sites but not strong think as of holding a basketball in your hand, you are able to hold the ball but not a very strong hold. Now in the case of affinity, think of the binding sites are strong and hold on to the immunogen. Look at a baseball on your hand don't you have a stronger grip on it than with the basketball. In short avidity is capacity to bind many antigens but not very strong. Affinity less antigens but a good binding. Hope this help

[ArchivalUser]

hello chintoo,
I hav just started but I feel I can tell in this way...avidity affinity...like in life ;
you cant have it all,in other words there is something lacking...paancho ungalia baraabar nahin hotin,,5
fingers are not of equal length,but they do complement each other!it helps to keep the feet on ground.

[ArchivalUser]

Thats great out everything in perspective and answers the question too thanks sandoc77

[ArchivalUser]

this is what i understood....

avidity depends on the binding site and we know that the IgM molecule has five of them attached together by the j chains, hence its valency or the binding sites are 10. hence it has a great avidity

but as we do class switching we make IGg, this is a single molecule, hence its valency decreases, but as we know there re constant mutations going on , in the antibody binding area, hence the one which has more affinity for the antibody produced by the mutation, will be choosen, and that will start proliferating, hence after sometime we will have AB with stronger affinity for antigen, this is called affinity maturation

hence as we go from IGm toIGg, we decrease the avidity, but increase the affinity

am i right?

[ArchivalUser]

yes you are and I wud like to add,
IgM is the the first responce so it has to be a general police,and as we know more about the Ag then we go specific like IgG.

[ArchivalUser]

thanks a lot sandoc