HERB - Pollen and allergy

[lklc]

wow. great info here.  thanks for the detailed research.  Intresting stuff
----- Original Message -----
From: "Kathleen Keeler" <kkeeler at unlserve.unl.edu>
To: <Herbalist at ansteorra.org>
Sent: Monday, May 01, 2000 10:25 AM
Subject: HERB - Pollen and allergy


> Greetings from Agnes
> I'm trying to get this right and its not easy
>
> Pollen, one of my text books says, is a collective term for pollen
> grains.
> Pollen grains are structures containing 2 or 3 cells, one of which will
> divide
> to become the sperm cell of the plant. Pollen goes from one plant
> (acting as
> male) to another plant (receiving as female) where on the stigma of the
> flower
> the sperm cell grows out of the pollen grain and grows as long tubes
> until it gets
> to the ovary down in the flower, were fertilization occurs and a new
> embryo is
> created.
>
> A pollen grain contains all the stuff of a cell, protein, nucleic acid,
> sugars, other carbohydrates...the lot. The pollen grain's outer wall
> (exine)
> has two functions--to resist drying, since drying out  will kill the
> cells inside, and to
> activate growth if the pollen grain falls in the right place (on the
> stigma of
> its own species).  The resisting drying makes pollen outer walls so hard
> they last
> millenia.  The activation proteins are apparently the ones that people
> become
> allergic to.  These proteins move out of the pollen grain and into the
> surrounding
> area. On the stigma, pollen tube development ensues.  In your nose,
> these
> chemicals are exposed to your immune system, which, in the case of
> allergic
> individuals, touches off the reaction.
>
> While ragweed's pollen cell chemistry contains protein molecules
> specific to
> ragweed the pollen grain also has molecules shared with other ragweeds
> and
> with composites generally. Maybe only the ragweed proteins touches off
> your
> immune reaction, but in launching its response, you are likely to make
> antibodies
> to every possible surface in the invading cell.  That means you will
> make antibodies
> to composite family proteins, even tho they didn't start it.  And that
> means that you
> will be sensitive to those proteins if you run into them later--in any
> context.
>
> Arent' the tests done to tell what people are allergic to skin tests?
> They rub a little cat
> dander and ragweed pollen and maple pollen on your skin, and if a welt
> appears,
> allergy is identified?
>
> So your immune system isn't fooled if a "known enemy" enters by a route
> other than
> the nose.
>
> And the problem is the complex proteins in the pollen grain, not the
> pollen grain's shape.
>
> Shape helps it sail through the air.  Ragweed is a bad allergen and
> sunflower isn't mainly
> because ragweed is wind pollinated and blankets its surroundings in
> pollen, hoping some
> gets to the next flower.  Ragweed pollen stays in the air well and
> there's LOTS of it.
> Sunflowers stick their pollen on bees and butterflies and don't make as
> much pollen and
> certainly don't throw it around.  (But apparently both have shared shape
> characteristics that
> tell the expert: Asteraceae pollen.)
>
> Still working on getting the details right.  Thanks for the chance to
> think this through!   Point out
> any discrepancies please.
>
> Agnes
> kkeeler1 at unl.edu
>
>
>
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