> From: Joy Anderson <[log in to unmask]>
>
> regards to immunology (but did study it in my
> graduate diploma of medical technology many years ago), but my
> understanding is that IgG is the small immunoglobulin that passes
> across the placenta (as you stated - classic example is anti-Rh), but
> that IgA is the one for all 'secretory' purposes, such as milk, lung
> lining, etc - it has a J-chain joining the two parts that are each
> like IgG molecules, and this J-chain results in the whole molecule
> being resistent to degradation (hence it survives in 'hostile'
> environments like a baby's gut).
>
> IgM, on the other hand, is a *huge* molecule that I thought could not
> get into milk *or* across the placenta.
>
> I thought that milk contains nearly all IgA except for the people who
> are genetically IgA-deficient, and they seem to compensate by having
> IgG in their milk. (Still not IgM.)

Thanks so much for contributing to this discussion.

I've been doing a fair bit of research and have come across numerous
references to breastmilk containing mostly IgA but containing all five
classes of immunoglobin. (IgG, IgA, IgM, IgD and IgE.) The Latrobe U tables
detailing antibacterial and antiviral properties of breastmilk contain
references to IgM. http://www.latrobe.edu.au/microbiology/table1.html

There are also lots of references to Secretory IgM, but I don't know enough
about immunology to know if this is relevant.

-- Jodine Chase

             ***********************************************

To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or digest)
To unsubscribe: unsubscribe lactnet
All commands go to [log in to unmask]

The LACTNET mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software together with L-Soft's LSMTP(TM)
mailer for lightning fast mail delivery. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html