proteins....

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anum

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no proteins can be absorbed without being digested to amino acids. But the immunoglobulins that a child gets from mother during lactation are absorbed .immunoglobulins are proteins plus are they not at risk of being digested in the stomach.i need help?is it concerned with enzymes.as none are present to digest immunoglobulins, but still how are they absorbed.

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no proteins can be absorbed without being digested to amino acids. But the immunoglobulins that a child gets from mother during lactation are absorbed .immunoglobulins are proteins plus are they not at risk of being digested in the stomach.i need help?is it concerned with enzymes.as none are present to digest immunoglobulins, but still how are they absorbed.

I believe some proteins can be absorbed without being fully digested.
 
I believe some proteins can be absorbed without being fully digested.
I don't see how - you only have transporters for amino acids, di- and tri-peptides in the small intestine. I am curious for the answer though.
 
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I don't see how - you only have transporters for amino acids, di- and tri-peptides in the small intestine. I am curious for the answer though.

under physiological Ph amino acids are charged. it depends on the molecular weight and the charge of the object that has to be transported across the menbrane.the tranport chanels are of specific configuration to accept only the smaller objects.protiens for that matter have a very high molecular weight.it is practically impossible to shuttle 'em across the bilipid membrane.Even the fenestrated capillaries donot permit the albumin and such proteins to cross the podocytes.is it not?
 
no proteins can be absorbed without being digested to amino acids. But the immunoglobulins that a child gets from mother during lactation are absorbed .immunoglobulins are proteins plus are they not at risk of being digested in the stomach.i need help?is it concerned with enzymes.as none are present to digest immunoglobulins, but still how are they absorbed.

Dietary proteins must be digested. I agree with that, even in infants. Proteins in mother's milk are acted upon by aminopeptidases. But such is not the case with colostral immunoglobulins.

In infants, colostral immunoglobulins are absorbed as such by the enterocytes by formation of tubules at the base of the apical microvilli. These tubules pinch off in the cell to form small vesicles that can transport the contents to the basolateral membrane and release their contents into the extracellular space. From there the macromolecules can be absorbed into the blood.

Why cleave immunoglobulins into its components? Immunoglobulin will be useless as an immuno-agent if you break it. :)
 
I am guessing Transcytosis....? That is what I learned in undergrad...?
 
Brown429, correct! :thumbup:
 
This thread makes me think of the end of "Grapes of Wrath," but I don't think that the IgA would survive in an adult stomach.

I agree with the above. If you remember those baby formula commercials with the broken-down peptides. It confirms that peptidases, etc. aren't mature in miniature humans.
 
This thread makes me think of the end of "Grapes of Wrath," but I don't think that the IgA would survive in an adult stomach.

I agree with the above. If you remember those baby formula commercials with the broken-down peptides. It confirms that peptidases, etc. aren't mature in miniature humans.

Is that the one where the man breast feeds the baby?
 
Is that the one where the man breast feeds the baby?

I thought that it was a woman who had just given birth, and wasn't she nursing a starving homeless man or something?

Anyway, I think that her colostrum supply had been pretty much spent at that point.
 
Dietary proteins must be digested. I agree with that, even in infants. Proteins in mother's milk are acted upon by aminopeptidases. But such is not the case with colostral immunoglobulins.

In infants, colostral immunoglobulins are absorbed as such by the enterocytes by formation of tubules at the base of the apical microvilli. These tubules pinch off in the cell to form small vesicles that can transport the contents to the basolateral membrane and release their contents into the extracellular space. From there the macromolecules can be absorbed into the blood.

Why cleave immunoglobulins into its components? Immunoglobulin will be useless as an immuno-agent if you break it. :)

yes that is convincing...but before reaching the enterocytes the immunoglobulins have to pass the stomach.
the acidic ph ,gastric juice and the whole protein digesting environment.How do Immunoglobulins survive that?
 
Though it is true that the acidic pH, gastric juice, etc will digest immunoglobulins, please consider also that a newborn does not have a mature digestive system yet. It has never really learned to completely process food yet. By way of compensation, as if mother nature has thought of this already, the digestive system of neonates allows the absorption of macromolecules temporarily. These macromolecules are absorbed in the ileum. Now in the case of colostral immunoglobulins, absorption happens only a short period of time after birth--the time of baby's first suck. Absorption is initially high then declines gradually just so to accomodate the infusion. From there, intestinal absorption of the immunoglobulins eventually will no longer be accomodated. This period is known as the "time of closure".

Same reason why mothers are encouraged to breastfeed the baby as soon as both become ready for their first mother-child intimacy interaction. They call it "rooming-in". :)
 
I'm guessing most people posting here either 1. arent med students or 2. slept through immuno. :smuggrin:
 
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SanDiegoSOD, their questions and arguments are okay for purposes of academic discourse. They asked because they want to know and discuss, or interact with other sdn forum members. It does not mean that they or the others, (myself and even you included) know more or know less about biochemistry and or immunology. Sometimes, they just wanna know if others have the same answer or understanding. Or, others might be asking the same question.. Just let people be, let us all learn together :)
 
I have to speak up here, acute2...

Your avatar is totally freaking me out. :scared:
 
To each his own avatar, Critical Mass. Thanks ;)
 
I'm guessing most people posting here either 1. arent med students or 2. slept through immuno. :smuggrin:

i am a second year medical student...am curious to know! its not a rule that everyone has to have 100 percent knowledge ,the subjects i am dealing with at the moment are physiology,biochemistry and anatomy .... thanks to people like you these questions are rarely asked in the class!:thumbdown:
 
:)
Though it is true that the acidic pH, gastric juice, etc will digest immunoglobulins, please consider also that a newborn does not have a mature digestive system yet. It has never really learned to completely process food yet. By way of compensation, as if mother nature has thought of this already, the digestive system of neonates allows the absorption of macromolecules temporarily. These macromolecules are absorbed in the ileum. Now in the case of colostral immunoglobulins, absorption happens only a short period of time after birth--the time of baby's first suck. Absorption is initially high then declines gradually just so to accomodate the infusion. From there, intestinal absorption of the immunoglobulins eventually will no longer be accomodated. This period is known as the "time of closure".

Same reason why mothers are encouraged to breastfeed the baby as soon as both become ready for their first mother-child intimacy interaction. They call it "rooming-in". :)


Thanks:thumbup::)
 
I thought that it was a woman who had just given birth, and wasn't she nursing a starving homeless man or something?

Anyway, I think that her colostrum supply had been pretty much spent at that point.

Oh, well, there is a good chance I skipped or slept through that class in high school. I do remember some book that was controversial because a man breast feeds a baby. I dunno.
 
Oh, well, there is a good chance I skipped or slept through that class in high school. I do remember some book that was controversial because a man breast feeds a baby. I dunno.

Speaking of avatars and milk, does your milkshake bring all the boys to the yard?
 
I have to speak up here, acute2...

Your avatar is totally freaking me out. :scared:

Is that really a woman Critical Mass? Looking at her hands I'm not quite so sure.

It also looks like someone's Myspace photo.
 
Is that really a woman Critical Mass? Looking at her hands I'm not quite so sure.

It also looks like someone's Myspace photo.

Well I didn't get it off of myspace, but I can't find the link anymore. I had that problem with the last avatar too.

Back onto the thread topic, I definitely think that this girl gets her daily protein allowance.
 
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