Kuyankha kwa Chitetezo cha Mthupi ndi Kuzindikira Thupi
Chitetezo cha mthupi ndi chimodzi mwa njira zovuta komanso zofunika kwambiri zodzitetezera m'thupi, kuteteza chamoyo ku ziwopsezo za tizilombo toyambitsa matenda monga mabakiteriya, mavairasi, tizilombo toyambitsa matenda, ndi bowa. Kuyankha kwa chitetezo cha mthupi kumatanthauza njira zosiyanasiyana zogwirira ntchito zomwe zimaphatikizapo mitundu yosiyanasiyana ya maselo ndi mamolekyu kuti azindikire ndikuwononga zinthu zakunja zomwe zimalowa m'thupi. Nkhaniyi ifotokoza mwatsatanetsatane momwe chitetezo cha mthupi chimazindikira chitetezo cha thupi, momwe chimayankhira ku ziwopsezo, ndi zina mwa zinthu zofunika kwambiri pa njirayi.
Chiyambi cha Kudzikonda Osati Kudzikonda
Chimodzi mwa ntchito zazikulu za chitetezo chamthupi ndi kuthekera kwake kusiyanitsa maselo a thupi ('ife') ndi maselo akunja ('osakhala ife'). Luso limeneli ndi lofunika kwambiri kuti chitetezo chamthupi chiwononge tizilombo toyambitsa matenda popanda kuvulaza maselo athanzi. Kuzindikira kumeneku kumachitika makamaka kudzera mu mamolekyu otchedwa Major Histocompatibility Complex (MHC), omwe amapezeka pamwamba pa maselo pafupifupi onse a thupi.
MHC imapereka zidutswa za mapuloteni, zomwe zimadziwika kuti ma peptide, ku maselo a T, omwe ndi gawo lofunika kwambiri la chitetezo chamthupi chosinthika. Pali magulu awiri akuluakulu a MHC: MHC class I imapezeka pafupifupi maselo onse okhala ndi nucleated ndipo imapereka ma peptide ochokera ku mapuloteni amkati mwa maselo, pomwe MHC class II imapezeka pa maselo omwe akuwonetsa antigen (maselo a dendritic, macrophages, ndi maselo a B) ndipo imapereka ma peptide ochokera ku mapuloteni omwe atengedwa kunja kwa selo. Maselo a T amazindikira ma peptide omwe amanyamulidwa ndi ma MHC awa: ngati peptide imachokera ku maselo a thupi, selo la T silidzayambitsa chitetezo chamthupi. Komabe, ngati peptide imachokera ku tizilombo toyambitsa matenda, selo la T lidzayatsidwa ndikupitiriza kuyankha chitetezo chamthupi.
Chitetezo Chobadwa Nacho ndi Chosinthika
Chitetezo cha mthupi chimagawidwa m'magawo awiri akuluakulu: chitetezo chamthupi chokhazikika ndi chitetezo chosinthika. Chitetezo chamthupi chokhazikika ndiye mzere woyamba wa chitetezo, ndipo yankho lake limakhala lachangu koma losalunjika kapena lokhala ndi "kukumbukira." Zigawo zazikulu za chitetezo chamthupi chokhazikika ndi monga khungu, mucosa, ma phagocyte (monga macrophages ndi ma neutrophils), maselo achilengedwe opha (NK cells), ndi mapuloteni osiyanasiyana a m'magazi monga chowonjezera.
Kumbali ina, chitetezo chamthupi chosinthika chimamveka ngati njira yachiwiri yodzitetezera yomwe imachedwa kuchitapo kanthu poyamba, koma yeniyeni kwambiri ndipo imatha "kukumbukira" tizilombo toyambitsa matenda kudzera mu kukumbukira kwa chitetezo chamthupi. Zigawo zazikulu za chitetezo chamthupi chosinthika ndi maselo a T ndi maselo a B. Maselo a B ndi omwe amachititsa kupanga ma antibodies makamaka motsutsana ndi ma antigen, pomwe maselo a T amagawidwa m'maselo a T othandizira ndi maselo a T omwe ali ndi poizoni, iliyonse imagwira ntchito yothandizira kuyambitsa maselo ena ndikuwononga maselo omwe ali ndi kachilomboka.
Masitepe Othandizira Chitetezo cha Mthupi
Kuyankha kwa chitetezo chamthupi kumaphatikizapo magawo angapo omwe cholinga chake ndi kuzindikira ndi kuwononga tizilombo toyambitsa matenda. Gawo loyamba, lodziwika kuti "kuwunika chitetezo chamthupi," ndi njira yomwe maselo a chitetezo chamthupi amawunika nthawi zonse kuti awone ngati pali tizilombo toyambitsa matenda. Tizilombo toyambitsa matenda tikalowa m'thupi, njira yodziwira ndi kuzindikira imayamba.
1. Kuzindikira ndi Kuzindikira: Maselo a dendritic ndi macrophages, akazindikira tizilombo toyambitsa matenda pogwiritsa ntchito ma receptors enaake monga ma Toll-like receptors (TLRs), phagocytose ndikugwiritsa ntchito tizilombo toyambitsa matenda. Kenako amapereka zidutswa za tizilombo toyambitsa matenda ku maselo a T kudzera mu mamolekyu a MHC.
2. Kuyambitsa: Ma antigen omwe amaperekedwa ndi MHC amadziwika ndi ma receptors omwe ali pa maselo a T ofanana. Maselo a T omwe azindikira antigen amayambitsidwa, zomwe zimapangitsa kuti achuluke komanso asinthe kukhala maselo oyambitsa omwe amatha kugwira ntchito yolimbana ndi tizilombo toyambitsa matenda. Maselo a B amayambitsidwanso kudzera mu kuyanjana ndi maselo a T ndi ma antigen ogwirizana nawo, zomwe zimapangitsa kuti ma antibodies apadera a antigenyo apangidwe.
3. Zothandiza: Maselo a T omwe ali ndi poizoni amawononga maselo omwe ali ndi kachilomboka kudzera m'njira zosiyanasiyana, kuphatikizapo kutulutsa tinthu tating'onoting'ono tomwe tili ndi perforin ndi granules zomwe zimayambitsa apoptosis m'maselo omwe akufuna. Pakadali pano, ma antibodies opangidwa ndi maselo a B amaukira tizilombo toyambitsa matenda kunja kwa selo ndikuwaika chizindikiro kuti awonongeke ndi zigawo zina za chitetezo chamthupi monga macrophages kapena kudzera mu njira yowonjezera.
4. Kukumbukira kwa Chitetezo cha Mthupi: Matenda akatha, maselo ena a T ndi maselo a B omwe akhudzidwa amasanduka maselo okumbukira. Maselo okumbukira amenewa amapitirirabe m'thupi ndipo amayankha mwachangu komanso moyenera ngati tizilombo tomwe timayambitsa matendawa talowanso m'thupi.
Kukhazikika kwa Chitetezo cha Mthupi
Chitetezo cha mthupi ndi chothandiza kwambiri komanso chofunikira kwambiri kuti munthu akhale ndi moyo, koma kusalinganika kwake kungayambitse mavuto osiyanasiyana azaumoyo. Kusowa kwa chitetezo chamthupi, kaya chobadwa nacho kapena chobadwa nacho, kumabweretsa kufooka kwa mphamvu yolimbana ndi matenda. Mosiyana ndi zimenezi, chitetezo chamthupi chochuluka kapena chosalamulirika chingayambitse matenda odziteteza okha, komwe chitetezo chamthupi chimaukira maselo a thupi, monga momwe zimachitikira mu multiple sclerosis kapena rheumatoid arthritis.
Matenda ena a chitetezo chamthupi ndi monga ziwengo, zomwe zimapangitsa kuti chitetezo chamthupi chizigwira ntchito mopitirira muyeso ku ma antigen osavulaza, monga mungu kapena zakudya zina. Kuchiza vutoli kumafuna chithandizo choyenera chamankhwala kuti chitetezo chamthupi chibwerere mwakale.
Kutseka
Chitetezo cha mthupi ndi njira zake zosiyanitsira pakati pa "kudzikonda" ndi "kusakhala ndi kudzikonda" ndi zina mwa zinthu zofunika kwambiri pa thanzi la munthu. Thanzi labwino la chitetezo cha mthupi ndilofunika kwambiri osati popewa matenda opatsirana okha komanso kuti thupi likhale lolimba kuti lipewe matenda odziteteza okha kapena ziwengo. Kumvetsetsa bwino za chitetezo cha mthupi kukupitirizabe kusintha, zomwe zimapanga njira zatsopano zamankhwala mu chithandizo cha chitetezo cha mthupi ndi katemera, zomwe zimapereka chiyembekezo chatsopano chochiza matenda ovuta okhudzana ndi chitetezo cha mthupi.
