Qhov sib txawv tseem ceeb ntawm cov kws tshaj lij thiab tsis yog cov kws tshaj lij antigen nthuav tawm cov hlwb yog cov kws tshaj lij antigen nthuav tawm cov hlwb yog cov khoom siv ntawm cov cell uas qhia MHC chav kawm II molecules nrog rau cov co-stimulatory molecules thiab cov qauv lees paub receptors, thaum tsis yog cov kws tshaj lij antigen nthuav tawm cov hlwb yog accessory cells qhia tsuas yog MHC class I molecules.
Ib qho tshuaj tiv thaiv kab mob tam sim no yog lub xov tooj ntawm tes uas qhia cov antigens khi los ntawm MHC cov protein ntawm nws qhov chaw. Nws tseem hu ua ib qho khoom siv ntawm tes. Cov txheej txheem no hu ua antigen nthuav qhia. Yog li, lub luag haujlwm tseem ceeb ntawm cov tshuaj tiv thaiv tam sim no yog ua cov antigens thiab nthuav tawm lawv mus rau T hlwb. Ntxiv mus, T hlwb tuaj yeem paub cov complexes los ntawm kev siv lawv cov T cell receptors (TCRs). Cov kws tshaj lij thiab tsis yog cov kws tshaj lij antigen-presenting cells yog ob hom antigen-presenting cells.
Dab tsi yog Professional Antigen Presenting Cells?
Antigen-tam sim no cov hlwb uas nthuav qhia MHC chav kawm II molecules nrog rau cov co-stimulatory molecules thiab cov qauv lees paub receptors feem ntau hu ua cov kws tshaj lij antigen-presenting cells. Lo lus "antigen-presenting cell" yog siv tshwj xeeb los piav txog cov neeg ua haujlwm antigen-presenting cells. Txawm li cas los xij, cov hlwb uas tsis yog kws tshaj lij antigen kuj tseem muaj peev xwm ntawm cov tshuaj tiv thaiv kab mob los ntawm MHC class I molecules.
Daim duab 01: Kev Tshaj Tawm Antigen nthuav tawm Cells
Cov tshuaj tiv thaiv kab mob ua haujlwm tau zoo heev ntawm kev tsim cov tshuaj tiv thaiv kab mob los ntawm phagocytosis lossis receptor-mediated endocytosis. Tom qab ntawd cov hlwb no ua cov antigens rau hauv peptide fragments thiab tso saib cov peptides uas tau khi rau MHC class II molecules ntawm lawv daim nyias nyias. Tom qab ntawd, T hlwb paub thiab cuam tshuam nrog cov antigen-MHC chav kawm II complex ntawm daim nyias nyias ntawm cov kws tshaj lij antigen-tam sim no ntawm tes. Ib qho ntxiv co-stimulatory teeb liab kuj yog tsim los ntawm cov kws tshaj lij antigen-kev nthuav qhia cov hlwb, ua rau ua kom T hlwb. Txhua tus kws tshaj lij cov tshuaj tiv thaiv-tam sim no tuaj yeem nthuav qhia MHC chav kawm I molecules. Muaj peb yam tseem ceeb ntawm cov kws tshaj lij antigen-tam sim no cov hlwb: dendritic hlwb, macrophages thiab B hlwb. Tsis tas li ntawd, cov hlwb dendritic nthuav tawm cov tshuaj tiv thaiv txawv teb chaws rau ob leeg pab thiab cytotoxic T hlwb, thaum macrophages thiab B hlwb nthuav tawm txawv teb chaws antigens nkaus xwb los pab T cells.
Dab tsi yog Cov Tshuaj Tiv Thaiv Tsis Zoo Tshaj Plaws?
Antigen-presenting cells uas qhia tsuas yog MHC chav kawm kuv cov molecules feem ntau hu ua non-professional antigen-presenting cells. Non-professional antigen-presenting cells suav nrog txhua hom cell nucleated hauv tib neeg lub cev. Cov hlwb no siv MHC chav kawm I molecule ua ke rau beta-2 microglobulin los tso saib endogenous peptides ntawm cov cell membrane. Cov peptides tuaj hauv cov hlwb; Yog li ntawd, lawv hu ua endogenous peptides (endogenous antigens).
Daim duab 02: Tsis yog-professional Antigen nthuav tawm Cells
Cytotoxic T hlwb muaj peev xwm cuam tshuam nrog endogenous antigens nthuav tawm siv MHC chav kawm I molecule. Cov kab mob kis kab mob thiab cov qog nqaij hlav qog nqaij hlav yog cov tsis yog cov tshuaj tiv thaiv kab mob uas tuaj yeem nthuav tawm cov tshuaj antigens hauv lawv mus rau cytotoxic T hlwb. Cov hlwb uas tsis yog kws tshaj lij antigen-tam sim no feem ntau tsis qhia MHC chav kawm II molecules.
Similarities between Professional and Non-professional Antigen Presenting Cells
- Kev tshaj lij thiab tsis yog kev tshaj lij cov tshuaj tiv thaiv kab mob yog ob yam sib txawv ntawm cov tshuaj tiv thaiv kab mob.
- Ob hom tuaj yeem nthuav tawm cov tshuaj tiv thaiv rau T hlwb ntawm MHC cov protein ntawm lawv cov cell membrane nto.
- Ob hom tuaj yeem ua cov tshuaj tiv thaiv ua ntej nthuav tawm rau T hlwb.
- Lawv tseem hu ua cov hlwb ntxiv.
- Lawv ua lub luag haujlwm tseem ceeb hauv kev hloov kho lub cev tiv thaiv kab mob hauv lub cev.
Qhov txawv ntawm cov kws tshaj lij thiab tsis yog tus kws tshaj lij Antigen nthuav tawm Cells
Cov tshuaj tiv thaiv zoo tshaj plaws yog cov khoom siv hluav taws xob uas nthuav qhia MHC chav kawm II cov molecules nrog rau cov co-stimulatory molecules thiab cov qauv lees paub receptors, thaum tsis yog cov kws tshaj lij antigen-presenting cells yog cov khoom siv hlwb uas nthuav tawm tsuas yog MHC class I molecules. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm cov kws tshaj lij thiab cov tsis muaj kev tshaj lij antigen-presenting cells. Tsis tas li ntawd, cov kws tshaj lij cov tshuaj tiv thaiv tam sim no tuaj yeem nthuav tawm cov tshuaj tiv thaiv rau ob tus neeg pab thiab cytotoxic T hlwb. Ntawm qhov tod tes, non-professional antigen-presenting cells tuaj yeem nthuav tawm antigens nkaus xwb los pab T cells.
Cov hauv qab no nthuav tawm qhov sib txawv ntawm cov kws tshaj lij thiab tsis yog cov kws tshaj lij antigen-kev nthuav qhia cov hlwb hauv daim ntawv teev npe rau kev sib piv ntawm ib sab.
Summary – Professional vs Non-professional Antigen Presenting Cells
Antigen-presenting cells tswj cov txheej txheem ntawm kev nthuav qhia antigen rau T hlwb ntawm MHC cov protein ntawm lawv cov cell membrane nto. Muaj ob hom antigen-presenting cells raws li cov kws tshaj lij thiab tsis yog cov kws tshaj lij antigen-presenting cells. Cov no ua lub luag haujlwm tseem ceeb hauv kev hloov kho lub cev tiv thaiv kab mob hauv lub cev. Professional antigen-presenting cells yog cov khoom siv ntxiv uas nthuav qhia MHC chav kawm II molecules nrog rau cov co-stimulatory molecules thiab cov qauv lees paub receptors, thaum tsis yog cov kws tshaj lij antigen-presenting cells yog cov khoom siv uas nthuav tawm tsuas yog MHC class I molecules. Yog li, qhov no piav qhia txog qhov sib txawv ntawm cov kws tshaj lij thiab cov neeg tsis muaj kev tshaj lij antigen nthuav tawm cov hlwb.
