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Globulin yog cov protein ntau uas muaj nyob hauv tib neeg lub cev thiab muaj kev tiv thaiv kab mob. Nws tseem hu ua immunoglobulin tshuaj. Thaum tib neeg lub cev tiv thaiv kab mob ntsib cov neeg txawv tebchaws txawv tebchaws, nws yuav tsim cov nyiaj sib txawv ntawm globulin raws li tus yam ntxwv ntawm tus neeg ntxeem tau. Yog tias tus neeg ntxeem tau nyuaj rau tshem tawm, nws yuav ua rau cov txheej txheem lymphatic tsim tau ntau dua tshuaj tiv thaiv kom txog rau thaum tus invader puas lawm. Koj tuaj yeem pom qhov immunoglobulin qauv tom qab ntawd
Los ntawm X-ray siv lead ua qhov tsis sib xws tsom xam, nws pom tias cov qauv yooj yim ntawm immunoglobulin tshuaj yog monomer muaj li ntawm 4 symmetrical polypeptide saw txuas nrog los ntawm disulfide bonds. Ob txoj saw nrog loj dua nyhav phaus hu ua hnyav saw. Ob txoj saw hlau hnyav hnyav me me hu ua lub teeb saw.
Cov ntu ntawm kwv yees li 110 amino acids nyob ze cov amino terminus (N-terminus) ntawm cov globulin hnyav saw thiab lub teeb pom kev sib txawv heev, hu ua thaj tsam sib txawv (V cheeb tsam), uas suav rau 4 (lossis 1/5) thiab 1/2 ntawm qhov hnyav saw thiab lub teeb saw feem. H saw thiab L saw ntawm cheeb tsam no txhua tus muaj 3 cov amino acid muaj pes tsawg leeg thiab kev npaj ua ntu zus.
Qhov chaw pob khawm nyob nruab nrab ntawm CH1 ~ CH2, uas nkag siab tau rau protease thiab yooj yim hydrolyzed. Nws yog nplua nuj nyob rau hauv proline, yog li nws yooj yim rau ncab thiab khoov, uas tau txais txiaj ntsig zoo rau ob txhais caj npab los khi ob lub epitopes ntawm qhov sib txawv ntawm tib lub sijhawm.
Antibody hais txog qhov immunoglobulin tshuaj uas yog tsim los ntawm cov ntshav ntshav sib txawv ntawm B lymphocytes hauv qab kev txhawb nqa ntawm antigen los ntawm lub cev tiv thaiv kab mob thiab tuaj yeem tshwj xeeb khi rau cov tshuaj antigen.
Cov tshuaj tiv thaiv kab mob muaj cov qauv sib npaug nrog 4 polypeptide saw, uas 2 yog cov saw hnyav ib yam (H saw) nrog ntev thiab loj dua tus txheeb ze hnyav hnyav; thiab 2 yog tib lub teeb saw (L saw) nrog luv dua thiab me dua tus txheeb ze hnyav hnyav. Cov saw txuas nrog los ntawm disulfide bonds thiab non-covalent bonds los tsim cov monomer molecule tsim los ntawm 4 polypeptide saw. Muaj ob hom hlua teeb: κ thiab λ, thiab tsib hom hnyav saw: μ, δ, γ, ε, α, α. Tag nrho cov tshuaj tiv thaiv kab mob tuaj yeem faib ua ob ntu, thaj av tsis tu ncua thiab thaj tsam sib txawv.
Hauv ib hom tsiaj, thaj tsam tas mus li ntawm cov tshuaj tiv thaiv kab mob sib txawv txhua tus muaj tib yam lossis yuav luag tib yam amino acid sib lawv liag. Cov cheeb tsam sib txawv nyob ntawm qhov kawg ntawm ob txhais caj npab ntawm "Y". Hauv cheeb tsam sib txawv, muaj ib feem me me ntawm cov amino acid seem uas hloov pauv tshwj xeeb, thiab cov muaj pes tsawg leeg thiab cov lej ntawm cov amino acid seem no feem ntau hloov pauv. Thaj av ntawd hu ua cheeb tsam hypervariable.
Thaj chaw hypervariable nyob ntawm qhov chaw ntawm cov molecule thiab suav nrog ntau tshaj 17 amino acid seem, thiab 2-3 yam tsawg kawg. Cov amino acid sib lawv liag ntawm thaj av hypervariable txiav txim siab qhov tshwj xeeb ntawm cov tshuaj tiv thaiv kab mob rau antigen. Ob qhov chaw tiv thaiv antigen ntawm cov tshuaj tiv thaiv kab mob zoo ib yam, nyob ntawm qhov kawg ntawm ob txhais caj npab, hu ua antigen-binding fragments (Fab). Tus tuav ntawm "Y" hu ua crystalline fragment (FC), thiab qab zib tau khi rau FC.
Xyoo 1964, Lub Koom Haum Saib Xyuas Kev Noj Qab Haus Huv Ntiaj Teb (World Health Organization) tau muaj lub rooj sib tham tshwj xeeb, hais txog globulins nrog cov tshuaj tiv thaiv kab mob thiab cov tshuaj tiv thaiv kab mob ntsig txog immunoglobulins (Ig), xws li myeloma protein, macroglobulinemia, cryoglobulinemia thiab lwm tus neeg mob ntshav qab zib tsis txaus immunoglobulins thiab subunits ntawm immunoglobulins ib txwm tshwm sim hauv cov neeg ib txwm muaj. Yog li ntawd, immunoglobulin tshuaj yog lub tswv yim ntawm cov txheej txheem tshuaj lom neeg, thiab tshuaj tiv thaiv kab mob yog lub tswv yim ntawm kev ua haujlwm lom neeg. Nws tuaj yeem hais tias tag nrho antibodies yog immunoglobulins, tab sis tsis yog txhua immunoglobulins yog cov tshuaj tiv thaiv kab mob.
IgM yog thawj hom Ig tsim los ntawm tus menyuam hauv plab, suav txog 5% -10% ntawm tag nrho ntshiab immunoglobulin tshuaj. Ntshav qab zib concentration yog li 1mg/ml.
Monomer IgM tau hais tawm ntawm lub xovtooj ntawm tes ua hom membrane-bound (mIgM), uas yog cov B cell antigen receptor (BCR).
Qhov zais IgM yog pentamer, Ig nrog qhov hnyav tshaj plaws hauv lub cev hnyav nrog 19S ntawm cov coefficient sedimentation. Nws yog hu ua macroglobulin, uas feem ntau tsis tuaj yeem hla ntawm cov hlab ntshav phab ntsa thiab feem ntau muaj nyob hauv cov ntshav.
Pentameric IgM muaj 10 Fab ntu uas muaj zog tiv thaiv kab mob antigen. Nws muaj 5 Fc antibody tau ntu, uas qhib ua kom yooj yim dua igg cov tshuaj tiv thaiv. cov ntuj ntshav pawg tshuaj tiv thaiv yog IgM, thiab kev hloov ntshav nrog cov ntshav tsis sib xws tuaj yeem ua rau muaj kev cuam tshuam loj heev hemolytic. IgM yog thawj cov tshuaj tiv thaiv kab mob sib xyaw thiab zais cia hauv cov txheej txheem ntawm ontogeny. Tus menyuam hauv plab tuaj yeem tsim IgM nyob rau lub sijhawm embryonic kev txhim kho lig.
Yog li, qhov nce ntawm IgM hauv cov ntshav ntshav qhia tias tus me nyuam hauv plab muaj tus kab mob hauv plab (xws li tus kab mob rubella lossis kab mob cytomegalovirus). IgM kuj tseem yog cov tshuaj tiv thaiv kab mob ntxov tshaj plaws uas tshwm sim thawj qhov kev tiv thaiv tsis txaus ntseeg, thiab yog lub cev "vanguard" tiv thaiv kev kis mob. Kev kuaj pom ntawm IgM hauv cov ntshav qhia tias tsis ntev los no tau muaj tus kab mob thiab tuaj yeem siv rau kev kuaj mob ntxov. IgM ntawm daim tawv nqaij nto yog lub hauv paus tseem ceeb ntawm B cell antigen receptors.
IgM tshwm thawj zaug thaum tus txheej txheem kev kis kab mob, tab sis nws tsis nyob ntev li qhov cim ntawm kev kis mob tsis ntev los no.
IgG yog lub npe luv ntawm immunoglobulin tshuaj G (IgG), yog cov tshuaj tiv thaiv kab mob tseem ceeb ntawm ntshiab, suav txog li 75% ntawm serum Ig. Ntawm lawv, 40-50% tau faib rau hauv cov ntshav, thiab qhov seem tau faib rau hauv cov ntaub so ntswg. IgG tsuas yog immunoglobulin tshuaj uas tuaj yeem hla dhau txoj hlab ntshav. Lub luag haujlwm ntawm IgG feem ntau ua lub luag haujlwm tiv thaiv hauv lub cev tiv thaiv kab mob, feem ntau yog cov tshuaj tua kab mob thiab tshuaj tua kab mob. Nws tuaj yeem tiv thaiv kab mob sib kis tau zoo nyob rau hauv kev teb rau mob qhua pias thiab kab mob siab A. Cov cim nws yog qhov tseem ceeb rau kev kuaj mob ntawm tej kab mob.
Cov ntsiab lus ntawm immunoglobuline A. (IgA) hauv tib neeg cov ntshav yog qhov thib ob rau IgG, suav txog 10-20% ntawm cov ntsiab lus immunoglobulin hauv cov ntshav. Los ntawm cov qauv kev pom, IgA muaj monomers, dimers, trimers thiab multimers. Raws li nws txoj haujlwm tiv thaiv kab mob, nws tau muab faib ua serotype thiab secretory type. Serotype IgA muaj nyob hauv cov ntshav, thiab nws cov ntsiab lus suav txog li 85% ntawm tag nrho IgA. Txawm hais tias serotype IgA muaj qee yam ua haujlwm ntawm IgG thiab IgM, nws tsis qhia txog kev tiv thaiv kab mob tseem ceeb hauv cov ntshav.
Cov IgA zais cia muaj nyob hauv cov kua qaub, xws li cov qaub ncaug, kua muag, colostrum, qhov ntswg thiab qhov hnoos qeev, cov kua hauv plab, tso zis, tawm hws thiab lwm yam. Qhov zais IgA yog lub cev tiv thaiv kab mob tseem ceeb ntawm lub cev mucosal hauv zos tiv thaiv kev tiv thaiv kab mob. Yog li ntawd, nws kuj tseem hu ua cov tshuaj tiv thaiv mucosal hauv zos. IgA tsis tuaj yeem hla dhau txoj hlab ntshav. Tsis muaj IgA cov tshuaj tiv thaiv hauv cov menyuam mos liab, tab sis zais IgA tuaj yeem tau los ntawm niam mis. Hauv 4 txog 6 lub hlis tom qab yug tus menyuam tshiab, IgA tuaj yeem tshwm sim hauv cov ntshav, thiab nws yuav maj mam nce ntxiv yav tom ntej, mus txog qhov siab tshaj thaum hluas.
IgE yog qhov zais cia immunoglobulin tshuaj nrog lub cev hnyav ntawm 196,000 thiab suav nrog ob txoj hlua teeb thiab ob txoj hlua hnyav. Nws yog tsim los ntawm cov ntshav ntshav hauv lamina propria ntawm nasopharynx, tonsils, bronchi, plab hnyuv mucosa, thiab lwm yam. tshuaj tiv thaiv uas ua rau muaj kev tsis haum rau hom I. Qhov pom tseeb tshaj plaws ntawm cov yam ntxwv tseem ceeb yog tias nws yog homologous. Tib neeg IgE tsuas yog tuaj yeem ua rau tib neeg thiab liab liab hlwb, thiab tsis muaj lwm yam tsiaj. IgE yog qhov rhiab tshaj rau cua sov ntawm cov immunoglobulins.
Ntawm tsib qhov immunoglobulins, IgE muaj qhov luv tshaj ib nrab ntawm lub neej, qhov siab tshaj plaws decomposition tus nqi thiab qis tshaj qhov sib xyaw ua ke, yog li nws suav rau feem pua qis tshaj hauv cov ntshav. Tus nqi IgE hauv ib txwm muaj tib neeg ntshav dej yog li 0.1-0.9 mg/L, thiab nws feem ntau me ntsis hauv txiv neej dua li poj niam. IgE hauv cov ntshav ntau dua hauv cov neeg mob uas ua xua lossis ua rau muaj kev tsis haum siab ntau dua li cov neeg ib txwm muaj, thiab cov neeg mob uas muaj mob hawb pob exogenous yog ntau zaus ntau dua li cov neeg ib txwm muaj. Yog li ntawd, qib IgE siab hauv cov ntshav feem ntau qhia pom tias muaj kev fab tshuaj caj ces lossis hom I ua xua.
Ntshav immunoglobuline D. (IgD) cov ntsiab lus yog qhov tsawg heev, nws tuaj yeem muaj nyob ua ib tus neeg tau txais daim nyias nyias nyob rau saum npoo ntawm B cells, thiab nws lub luag haujlwm tuaj yeem koom nrog hauv kev pib tsim cov tshuaj tiv thaiv los ntawm B cells. Nws lub luag haujlwm tseem muaj feem cuam tshuam nrog qee yam autoantibodies thiab tiv thaiv cov tshuaj tiv thaiv kab mob, xws li tshuaj tiv thaiv nuclear, tshuaj tiv thaiv kab mob hauv qab daus, tiv thaiv cov thyroid tiv thaiv kab mob, tiv thaiv kab mob diphtheria toxoid antibodies, thiab tetanus toxoid antibodies yog txheeb ze.
Los ntawm kab lus no, peb tuaj yeem paub tus immunoglobulin qauv thiab nws txoj haujlwm. Antibodies tuaj yeem ua ke nrog antigens (ob qho tib si txawv teb chaws thiab tus kheej) txhawm rau tshem tawm cov neeg txawv txav txawv txav xws li cov kab mob me me thiab kab mob cab, tshem tawm cov co toxins uas lawv tso tawm lossis tshem tawm qee yam antigens tus kheej, yog li lub cev tswj hwm qhov qub.
Tab sis qee zaum nws kuj ua rau muaj kev puas tsuaj rau lub cev, xws li tsim qee cov autoantibodies xws li tshuaj tiv thaiv kab mob nuclear, tiv thaiv kab mob DNA ob npaug, thiab tiv thaiv cov tshuaj tiv thaiv thyroglobulin, uas yuav ua rau tib neeg lub cev tsis zoo.
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