LEWIS BLOOD GROUP

LEWIS BLOOD GROUP SYSTEM
• Two major antigens: Lea and Leb
• They are not true red cell antigens
• Lewis antigens are synthesized in secretary tissue, such
as gut epithelium, and released into the plasma as
soluble glycolipids
• They are then adsorbed onto the red cell surface from
the plasma
• This binding is reversible (i.e. Lewis antigens may
disappear from the red cell surface)
• These antigens may be lost from the red cell surface of
stored red cells
• therefore, you always need to use fresh red cells when
you want to detect Lewis antigens or anti-Lewis
antibodies
• Lewis antigens show variable expression from
individual to individual (pregnant women often type
as Le(a-b-) )
• They are also unstable on storage
• They develop only during the first 12-15 months after
birth
• Presence of the Leb antigen is associated with the
development of peptic ulcers and stomach cancer
• This is thought to to be due to the fact that the Leb
antigen, expressed on the cells of the mucosal surface
of the stomach act as receptor for Helicobacter pylori
• anti-Lea and anti-Leb are often type IgM naturally
occurring antibodies (developed by type Le(a-b-)
individuals)
• They generally react best at temperatures below 37°C
• anti-Lea and anti-Leb are usually not clinically
signficant and therefore it is not usually necessary to
provide antigen negative blood to someone who does
not express Lewis antigens
• Lewis antibodies do not cause HDFN as fetal and
newborn red cells lack Lea and Leb antigens

[@digireviews4716]

Thanks for uploading this lecture 💓✨

[@somchart285]

يسلم من رباك

[@medlecto5507]

Thank you ❤️

[@djelaoudjirima7874]

Thnkuiuu

[@AngelGonzalez-nu4fx]

thank zou so much ! perfectly explained!!

[@dr.mohddanishstudyzaheer2558]

Good explanation

[@user-kl6zv5fb8z]

Thank you very much 😢❤❤❤❤❤❤

[@djelaoudjirima7874]

From Algeria thnk u

[@medlecto5507]

You are welcome 😊

[@bridgetshepherd439]

Thanks alot for the explicit explanation

[@medlecto5507]

You are most welcome

[@zahrabendekken1766]

You explain very well, thanks from Algeria

[@medlecto5507]

You are welcome!

[@ikram2326]

Thank you!

[@medlecto5507]

You're welcome!

[@bridgetshepherd439]

Thanks alot. Explicit explanation 👌

[@dr.mohddanishstudyzaheer2558]

❤ your introduction brother

[@medlecto5507]

You like it?

[@nashavie2006]

thank you! I've had a hard time understanding this part during my review season

[@medlecto5507]

Glad it helped!

[@user-qf4fu5xw1p]

amazing explanation thank u from dubai

[@medlecto5507]

Most welcome!

[@dr.mohddanishstudyzaheer2558]

Your qualifications please

[@user-fe8zt2xv2t]

Sir Correction please.... i think it's not pyroli it is Pylori....
& sir i have a question..... in which condition we can receive a+b+ antigen ?

[@medlecto5507]

Yes H.Pylori………..No there is no as such condition for a+b+……….Good you listen lecture carefully and ask a question.

[@dr.zainabshahid7736]

Thankss sir I hope will clear my DHA exam inshallah

[@medlecto5507]

Best of luck

[@dr.zainabshahid7736]

@@medlecto5507 thanks so much for the concern sir

[@dr.zainabshahid7736]

Inshallah i cleared my exam...

[@medlecto5507]

inshaallah …..Best of luck ✨

[@sanjaykumar-ew6mb]

Your video quality isn't good
But topic and presentation is awesome sir ❤❤

[@medlecto5507]

Ok next time