Διαφορά μεταξύ των αναθεωρήσεων του «Χρήστης:Dmtrs32/πρόχειρο»

Resultant plasma cells secrete large amounts of antibody and either stay within the SLO or, more preferentially, migrate to bone marrow.<ref name=":10" />
 
===Ενεργοποίηση ανεξάρτητη από Τ κύτταρα T cell-independent activation===
{{Main|T independent antigen (TI)}}
Τα αντιγόνα που ενεργοποιούν τα Β κύτταρα χωρίς τη βοήθεια των Τ κυττάρων είναι γνωστά ως [[ανεξάρτητα αντιγόνο Τ (ΤΙ) | ανεξάρτητα αντιγόνα Τ κυττάρων (ΤΙ)]]
Antigens that activate B cells without T cell help are known as [[T independent antigen (TI)|T cell-independent (TI) antigens]]<ref name=":0" /> and include foreign polysaccharides and unmethylated CpG DNA.<ref name=":8" /> They are named as such because they are able to induce a humoral response in organisms that lack T cells.<ref name=":0" /> B cell response to these antigens is rapid, though antibodies generated tend to have lower affinity and are less functionally versatile than those generated from T cell-dependent activation.<ref name=":0" />
Antigens that activate B cells without T cell help are known as [[T independent antigen (TI)|T cell-independent (TI) antigens]]<ref name=":0" /> και περιλαμβάνουν ξένους πολυσακχαρίτες και μη μεθυλιωμένο CpG DNA.
and include foreign polysaccharides and unmethylated CpG DNA.<ref name=":8" /> Ονομάζονται ως τέτοια επειδή είναι σε θέση να προκαλέσουν χυμική αντίδραση σε οργανισμούς που στερούνται Τ κυττάρων.
They are named as such because they are able to induce a humoral response in organisms that lack T cells.<ref name=":0" /> Η απόκριση των Β κυττάρων σε αυτά τα αντιγόνα είναι ταχεία, αν και τα αντισώματα που παράγονται τείνουν να έχουν χαμηλότερη συγγένεια και είναι λιγότερο λειτουργικά ευέλικτα από αυτά που δημιουργούνται από την εξαρτώμενη από Τ κύτταρα ενεργοποίηση.
B cell response to these antigens is rapid, though antibodies generated tend to have lower affinity and are less functionally versatile than those generated from T cell-dependent activation.<ref name=":0" />
 
Όπως και με τα αντιγόνα TD, τα κύτταρα Β που ενεργοποιούνται από τα αντιγόνα ΤΙ χρειάζονται επιπλέον σήματα για να ολοκληρώσουν την ενεργοποίηση, αλλά αντί να τα λαμβάνουν από τα Τ κύτταρα, παρέχονται είτε με αναγνώριση και σύνδεση ενός κοινού μικροβιακού συστατικού με [[Toll-like receptor | toll- όπως οι υποδοχείς (TLR)]] ή με εκτεταμένη διασταύρωση των BCR με επαναλαμβανόμενους επιτόπους σε ένα βακτηριακό κύτταρο.
As with TD antigens, B cells activated by TI antigens need additional signals to complete activation, but instead of receiving them from T cells, they are provided either by recognition and binding of a common microbial constituent to [[Toll-like receptor|toll-like receptors (TLRs)]] or by extensive crosslinking of BCRs to repeated epitopes on a bacterial cell.<ref name=":0" /> B cells activated by TI antigens go on to proliferate outside lymphoid follicles but still in SLOs (GCs do not form), possibly undergo immunoglobulin class switching, and differentiate into short-lived plasmablasts that produce early, weak antibodies mostly of class IgM, but also some populations of long-lived plasma cells.<ref name=":11">{{Cite journal|title = Long-Lived Bone Marrow Plasma Cells Are Induced Early in Response to T Cell-Independent or T Cell-Dependent Antigens|journal = The Journal of Immunology|date = 2012-06-01|issn = 0022-1767|pmc = 4341991|pmid = 22529295|pages = 5389–5396|volume = 188|issue = 11|doi = 10.4049/jimmunol.1102808|first1 = Alexandra|last1 = Bortnick|first2 = Irene|last2 = Chernova|first3 = William J.|last3 = Quinn|first4 = Monica|last4 = Mugnier|first5 = Michael P.|last5 = Cancro|first6 = David|last6 = Allman}}</ref>
As with TD antigens, B cells activated by TI antigens need additional signals to complete activation, but instead of receiving them from T cells, they are provided either by recognition and binding of a common microbial constituent to [[Toll-like receptor|toll-like receptors (TLRs)]] or by extensive crosslinking of BCRs to repeated epitopes on a bacterial cell.<ref name=":0" /> Τα κύτταρα Β που ενεργοποιούνται από τα αντιγόνα TI πολλαπλασιάζονται έξω από τα λεμφοειδή ωοθυλάκια αλλά εξακολουθούν να βρίσκονται σε SLOs (οι GC δεν σχηματίζονται), ενδεχομένως υποβάλλονται σε αλλαγή τάξης ανοσοσφαιρίνης και διαφοροποιούνται σε βραχύβιους πλασμαβλάστες που παράγουν πρώιμα, αδύναμα αντισώματα κυρίως της κατηγορίας IgM, αλλά και ορισμένους πληθυσμούς μακροζωίων κυττάρων πλάσματος.
As with TD antigens, B cells activated by TI antigens need additional signals to complete activation, but instead of receiving them from T cells, they are provided either by recognition and binding of a common microbial constituent to [[Toll-like receptor|toll-like receptors (TLRs)]] or by extensive crosslinking of BCRs to repeated epitopes on a bacterial cell.<ref name=":0" /> B cells activated by TI antigens go on to proliferate outside lymphoid follicles but still in SLOs (GCs do not form), possibly undergo immunoglobulin class switching, and differentiate into short-lived plasmablasts that produce early, weak antibodies mostly of class IgM, but also some populations of long-lived plasma cells.<ref name=":11">{{Cite journal|title = Long-Lived Bone Marrow Plasma Cells Are Induced Early in Response to T Cell-Independent or T Cell-Dependent Antigens|journal = The Journal of Immunology|date = 2012-06-01|issn = 0022-1767|pmc = 4341991|pmid = 22529295|pages = 5389–5396|volume = 188|issue = 11|doi = 10.4049/jimmunol.1102808|first1 = Alexandra|last1 = Bortnick|first2 = Irene|last2 = Chernova|first3 = William J.|last3 = Quinn|first4 = Monica|last4 = Mugnier|first5 = Michael P.|last5 = Cancro|first6 = David|last6 = Allman}}</ref>
 
=== Memory B cell activation ===
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