Key Difference – HLA vs MHC
Cov tshuaj tiv thaiv kab mob yog tsim los ntawm kev cuam tshuam ntawm cov tswv tsev cell los ntawm cov kab mob. Cov hlwb sib txawv thiab cov molecules uas muaj nyob rau hauv lub cev tiv thaiv kab mob koom nrog hauv cov txheej txheem no. Tib neeg Leukocyte Antigen (HLA) thiab Major Histocompatibility Complex (MHC) molecules yog ob qho tseem ceeb ntawm kev tiv thaiv kab mob. Lawv koom nrog hauv kev lees paub ntawm cov kab mob antigens thiab kev sib koom tes nrog lwm lub cev tiv thaiv kab mob los tsim cov tshuaj tiv thaiv kab mob. MHC molecules feem ntau muaj nyob rau hauv ntau hom vertebrates thaum HLA tsuas muaj nyob rau hauv tib neeg. Qhov no yog qhov sib txawv tseem ceeb ntawm HLA thiab MHC.
HLA yog dab tsi?
Lub MHC molecules ntawm tib neeg yog encoded los ntawm cov noob complex hu ua Human Leukocyte Antigen (HLA) uas muaj nyob rau ntawm chromosome 06. Nws yog suav hais tias yog polymorphic, uas muaj ntau hom alleles. Qhov no polymorphic xwm ntawm HLA gene complex muab kev kho kom zoo ntawm lub cev tiv thaiv kab mob uas muaj cov hlwb tshwj xeeb uas ua cov txheej txheem tshem tawm cov kab mob thiab tso tseg lawv txoj kev loj hlob. MHC molecules tuaj yeem muab faib ua ob chav loj, MHC Class I thiab MHC Class II. HLAs sib raug rau ob chav MHC hauv ntau hom, muab cov haujlwm sib txawv rau txhua hom chav kawm.
HLA – A, HLA – B and HLA – C encode for MHC Class I molecules. Qhov no yeej muaj nyob rau hauv cell mediated tiv thaiv kab mob uas nthuav tawm cov protein ntau (peptides) los ntawm sab hauv ntawm tes. Thaum lub sij hawm ntxeem tau ntawm tes los ntawm cov kab mob thiab lwm yam kab mob intracellular, cov tawg ntawm cov kab mob raug coj los ntawm HLA system thiab raug coj mus rau saum npoo ntawm tes. Qhov no pib lub cev tiv thaiv kab mob qhov twg cov kab mob kis tau raug lees paub los ntawm Tc hlwb thiab thaum kawg raug rhuav tshem.
Daim duab 01: Human HLA complex
HLA – DP, HLA – DR, HLA – DQ, HLA – DOA, HLA – DOB encode for MHC Class II molecules. Cov HLA gene complex tam sim no muaj antigens rau T lymphocytes uas tau muab los ntawm sab nrauv ntawm tes. Kev nthuav qhia ntawm antigens los ntawm cov noob caj noob ces pib ua kom nrawm nrawm ntawm Th cells. Qhov no ua rau kev txhawb nqa ntawm B hlwb hauv kev tsim cov tshuaj tiv thaiv kab mob rau cov tshuaj tiv thaiv tshwj xeeb uas nthuav tawm.
Lwm yam tshaj li kev encoding MHC molecules, HLA noob complex muaj lwm lub luag haujlwm hauv cov hlwb. Lawv raug suav hais tias yog qhov laj thawj tseem ceeb rau kev hloov pauv tsis lees txais. Yog tias muaj kev hloov pauv hauv HLA gene complex, nws ua rau cov kab mob autoimmune. Qhov sib txawv ntawm HLA noob complex nyob rau hauv cov pej xeem txiav txim siab cov lus teb sib txawv rau cov kab mob sib kis.
MHC yog dab tsi?
Major Histocompatibility Complex (MHC) cov molecules ua lub luag haujlwm tseem ceeb hauv kev lees paub cov khoom txawv teb chaws lossis cov tshuaj tiv thaiv uas cuam tshuam kev ua haujlwm ntawm cov hlwb. Lawv yog cov cell nto proteins uas koom nrog hauv kev sib txuas ntawm antigens. Cov antigens no yog muab los ntawm ntau hom invading pathogens los ntawm ob qho tib si intracellular thiab extracellular txoj kev. Thaum khi rau MHC molecules cov antigens tau nthuav tawm rau T hlwb uas suav nrog T hlwb (TH) thiab cytotoxic T hlwb (TC). MHC cov molecules muaj cov txheej txheem tshwj xeeb los tiv thaiv kev pib ntawm lub cev tiv thaiv kab mob tiv thaiv tus tswv ntawm tus kheej antigens. Thaum lub sij hawm degradation ntawm cell proteins, peptide particles ntawm txhua cov protein raug coj mus rau ntawm tes ntawm MHC molecules. Cov peptide particles no hu ua epitopes. Lawv muab cov ntaub ntawv rau MHC molecules kom paub qhov txawv ntawm tus kheej thiab tsis yog nws tus kheej antigens thiab ua raws li. MHC molecules yog ob pawg loj; MHC Class I thiab MHC Class II.
Txhua lub hlwb nucleated muaj MHC Class I molecules ntawm lawv cov cell. Lawv ua haujlwm los kuaj xyuas cov antigens uas tsis yog tus kheej los ntawm tus kheej-antigens tam sim no nyob rau hauv lub cell thiab ntawm Tc hlwb los pib lub cev tiv thaiv kab mob. Tc hlwb tshwj xeeb tshaj yog muaj co-receptor molecule CD8. MHC Class I molecules ua rau qhov pib ntawm cov cell lysis ncaj qha los ntawm Tc hlwb los ntawm kev nthuav tawm cov tshuaj antigens ntawm CD8 co-receptor molecules. Txoj kev nthuav qhia antigen hauv MHC Class I molecules yog lub npe hu ua endogenous txoj hauv kev vim peptides uas tau los ntawm cytosolic proteins muaj nyob rau hauv MHC Class I molecules. MHC Class I molecules yog encoded los ntawm HLA gene complex (HLA-A, HLA-B thiab HLA-C) uas muaj nyob rau ntawm Chromosome 6 thiab kuj los ntawm cov beta subunits uas muaj nyob rau ntawm chromosome 15.
Figure 02: MHC
Antigen Presenting cells (APC) uas suav nrog B hlwb, dendritic cells thiab macrophages nthuav qhia MHC Class II molecules ntawm lawv cov cell. Kev nthuav qhia ntawm antigens los ntawm MHC Class II molecules txawv ntawm MHC Class I antigen kev nthuav qhia. Thaum MHC Class II molecules ntsib ib qho antigen, cov antigen raug coj mus rau hauv lub cell uas cov antigen tau ua tiav. Tom qab ntawd, ib qho epitope uas yog ib feem ntawm ib qho antigen raug coj mus rau saum npoo ntawm tes. Qhov no epitope paub txog cov khoom sib ntxiv, nws tus kheej lossis tsis yog nws tus kheej antigen hu ua paratope thiab khi rau nws. MHC Class II molecules nthuav tawm cov tshuaj tiv thaiv kab mob los pib tiv thaiv kab mob los ntawm lwm lub hlwb hauv kev tiv thaiv kab mob. T pab (Th) hlwb nrog co-receptor molecule CD4 koom nrog hauv kev pib ntawm cov lus teb ntawm kev tiv thaiv kab mob. MHC Class II molecules yog encoded los ntawm HLA-D noob complexes uas muaj ob hom alpha thiab beta chains.
HLA thiab MHC yog dab tsi?
- Ob hom yog cov tshuaj tiv thaiv uas muaj nyob rau ntawm cov chaw ntawm tes thiab ntawm cov khoom siv caj ces ntawm cov hlwb.
- Ob leeg koom nrog hauv ib qho kev ua haujlwm uas yog, pab lub cev tiv thaiv kab mob hauv lub cev kom paub txog cov kab mob nkag mus thiab tiv thaiv nws qhov sib ntxiv hauv lub cev.
- Ob leeg koom nrog kev tswj hwm lub cev tiv thaiv kab mob thiab tiv thaiv kab mob.
Qhov txawv ntawm HLA thiab MHC yog dab tsi?
HLA vs MHC |
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| HLA yog cov noob caj noob ces tam sim no hauv tib neeg uas nkag mus rau MHC molecules. | MHC yog cov molecules uas ua lub luag haujlwm tseem ceeb hauv kev lees paub cov khoom txawv teb chaws; antigens uas cuam tshuam kev ua haujlwm ntawm cov hlwb. |
| HLA muaj nyob rau hauv tib neeg nkaus xwb. | MHC cov molecules feem ntau muaj nyob rau hauv vertebrates. |
| HLA encode rau MHC Class I thiab MHC Class II molecules. | MHC koom nrog kev lees paub ntawm cov khoom txawv teb chaws; antigens. |
Summary – HLA vs MHC
HLA thiab MHC cov molecules yog qhov tseem ceeb ntawm kev tiv thaiv kab mob. Qhov sib txawv ntawm HLA thiab MHC yog tias, MHC cov molecules feem ntau pom muaj nyob hauv ntau lub cev nqaij daim tawv thaum HLA tsuas yog pom hauv tib neeg. HLA yog ib tug gene complex tam sim no nyob rau hauv chromosome 06 uas encodes rau ob chav kawm MHC molecules. MHC cov molecules koom nrog hauv kev lees paub ntawm antigens thiab tso tawm cov antigens rau lwm lub cev tiv thaiv kab mob txhawm rau pib cov tshuaj tiv thaiv kab mob. MHC molecules yog ob chav kawm loj. MHC Class I molecules yog encoded los ntawm HLA gene complex (HLA-A, HLA-B thiab HLA-C) muaj nyob rau ntawm Chromosome 6 thiab kuj los ntawm cov beta subunits muaj nyob rau ntawm chromosome 15. MHC Class II molecules yog encoded los ntawm HLA-D noob complex.
Download the PDF Version of HLA vs MHC
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline lub hom phiaj raws li daim ntawv ceeb toom. Thov download PDF version ntawm no Qhov txawv nruab nrab ntawm HLA thiab MHC
