Home >Documents >Dasar Imunologi

Dasar Imunologi

Date post:17-Dec-2015
Category:
View:80 times
Download:1 times
Share this document with a friend
Description:
IMUNOLOGI
Transcript:

KONSEP DASAR IMUNOLOGI 1Pengampu : Praptiwi HAcuan materi ajar :1. Pembentukan sel imun2. Sistem imunitas tubuh

1. PEMBENTUKAN SEL IMUNImunitas berarti perlindungan terhadap penyakit, dengan pengertian lebih spesifik yaitu penya-kit infeksi.Berbagai jenis sel imun terjadi dari progenitor atau prekursornya. Gambar dibawah memperlihatkan sel-sel imun yang berasal dari sumsum tulang, memroduksi sel induk hematopoietic stem cell yang menghasilkan beragam tipe sel darah, serta elemen lain.

Sumber : Morgan, 2014.

2. SISTEM IMUNITAS TUBUHSel sel dan molekul molekul yang bertanggungjawab untuk imunitas, membentuk sistem imun. Respon kolektif sel dan molekul tersebut yang terkoordinasi terhadap pengenalan dengan substansi (benda) asing, disebut respon imun. Fungsi fisiologik sistem imun adalah pertahanan melawan mikroba infeksius, bahkan substansi asing non infeksius juga dapat menimbulkan respon imun. Infeksi adalah masuk dan berkembangbiaknya mikroba infeksius (patogen) dalam tubuh. Infeksi pada manusia disebabkan oleh berbagai unsure pathogen dalam lingkungan di sekitar, misalnya bakteri, virus, fungus, protozoa, dan parasit. Infeksi pada orang normal pada umumnya singkat, dan jarang meninggalkan kerusakan yang menetap. Sistem imun memberikan respon dan melindungi tubuh terhadap unsure patogen. Selanjutnya diketahui bahwa mekanisme tubuh untuk melindungi terhadap infeksi dan mengusir substansi asing, pada keadaan tertentu dapat menimbulkan kerusakan jaringan tubuh. Lebih jauh, fenomena imunologik yang sangat beragam dapat dihubungkan satu dengan yang lain melalui penjelasan biokemik dan struktur komponen-komponen yang terlibat dalam sistem imun. Pemeriksaan imunobiologi dan imuno-kimia menjadi penunjang diagnosis, sebagai pedoman dalam memenej penderita. Respon imun sangat bergantung pada kemampuan sistem imun untuk mengenali molekul asing (antigen) dalam patogen potensial, kemudian membangkitkan reaksi yang tepat untuk mengusir sumber antigen. Limfosit sebagai unsur utama sistem imun, akan mengenali antigen, diikuti oleh fase efektor yang melibatkan berbagai ojenis sel.

GambarPerkembangansellimfositberasaldariselinduknya.

Sumber :Biochemistryden Satish, 2014,

GambarLimfosit, an-tibodi,dan antigen.

Sumber : www.shutter-stock.com, 2014.

GambarFungsisel T helper.

Sumber :Grundlagen des

Particularly important was the work ofPaul Ehrlich, who proposed theside-chain theoryto explain the specificity of theantigen-antibody reaction; his contributions to the understanding of humoral immunity were recognized by the award of a Nobel Prize in 1908, which was jointly awarded to the founder of cellular immunology,Elie Metchnikoff.

Gambar Organ organ dalamsistemimun.

Sumber : aids.gov, 2014.

Sumber : virtualmedicalcentre.com, 2014.

Complement system -Wikipedia, 2014.Thecomplement systemhelps or complements the ability of antibodies andphagocyticcells to clearpathogensfrom an organism. It is part of theimmune systemcalled theinnate immune systemthat is not adaptable and does not change over the course of an individual's lifetime. However, it can be recruited and brought into action by theadaptive immune system.The complement system consists of a number of small proteins found in the blood, in general synthesized by theliver, and normally circulating as inactive precursors (pro proteins). When stimulated by one of several triggers,proteasesin the system cleave specific proteins to releasecytokinesand initiate an amplifying cascade of further cleavages. The end result of this activation cascade is massiveamplificationof the response andactivationof the cell-killingmembrane attack complex. Over 30 proteins and protein fragments make up the complement system, includingserum proteins,serosalproteins, andcell membrane receptors. They account for about 5% of the globulin fraction of blood serum and can serve asopsonins.Threebiochemical pathwaysactivate the complement system: theclassical complement pathway, thealternative complement pathway, and thelectin pathway depicted below.

Sumber : Mayer, 2011.

GambarJalurklasik.Antibodi yang berasaldarisel B ((limfosit B)mengikat antigen, sehinggamencegahpatogenmemasukiselinang (host).Sumber :SaidulNaik, 2014.

GambarJalurlectin.

Sumber : classes.midlandstech.edu, 2014.

Gambar Jalur alternatif.

Sumber : immunopaedia.org, 2014.

Lectin pathwaya. Phagocytosis by macrophages induces release of chemicals that stimulate the liver to produce carbohydrate binding proteins (lectins)b. One such lectin, mannose-binding lectin (MBL) binds to mannose on bacterial cells walls and on some viruses.c. MBL opsonizes and activates C2 and C4 to activate C3.d. C3 activation can result in cell lysis, inflammation, and opsonization.e. Complement is deactivated by host-regulatory proteins and water.

Alternative pathway1. Aktivasi C3, memerlukanFaktor B dankation Mg2+2. amplifikasiloopoleh C3. 3. pengendalian loop amplifikasi4. stabilisasi C convertaseolehpermukaanaktivator (protektor).

GambarOpsonisasibakteri.

Sumber : pathmicro.med.sc.edu, 2014.

DaftarPustakaAbbas AK, Lichtman AH, Pillai Shiv. Cellular and Molecular Immunology 7th ed. Philadelphia: Elsevier Saunders, 2012; pp 1-14.aids.gov. Organs of the immune system, 2014.classes.midlandstech.edu. Lectin complement pathway, 2014.Immunopaedia. Org. Alternative complement pathway, 2014.Mayer G. Complement. Immunology Chapter two. Microbiology and Immunology on-line. University of South California, 2011. Morgan ME. Theibdimmunologist.com. Immune cell generation, 2014.SaidulNaik. appsgroup.blogspot.com, 2014.SitiBoedinaKresno. Imunologi: Diagnosis danProsedurLaboratoriumedisike 4. Jakarta: BalaiPenerbitFakultasKedokteranUniversitas Indonesia, 2001; hal 1-13.virtualmedicalcentre.com, Immune system, 2014.Wikipedia. Immunity, 2014.

Signs of Allah in Our Immune System Islamcan.com, 2014.Every day, a war is fought in the innermost parts of your body unperceived by you. On the one side are viruses and bacteria that aim to intrude into your body and take it under control and on the other are the immunity cells that protect the body against these enemies.

First, the soldiers who swallow and neutralize the enemy soldiers (phagocytes) arrive at the battleground. However, sometimes the fight is tougher than these soldiers can handle. On such occasions, other soldiers (macrophages) are summoned up. Their involvement causes alarm in the target area and other soldiers (helper T cells) are also called to battle.

These soldiers are very familiar with the local populace. They quickly distinguish their own army from that of the enemy. They immediately activate the soldiers assigned to weapon production (B cells). These soldiers have extraordinary abilities. Although they never see the enemy, they can produce weapons which will render the enemy ineffectual. In addition, they carry the weapons they produce as far as they should be taken. During this journey, they succeed in the difficult task of not causing any harm either to themselves or to their allies. Later, the striker teams cut in (killer T cells). These discharge the poisonous material they carry on themselves at the most vital spot of the enemy. In case of victory, another group of soldiers arrives at the battleground (suppressor T cells) and sends all the warriors back to their camp. The soldiers who arrive at the battleground last (memory cells) record all relevant information about the enemy, so that it can be used in the event of a similar invasion in the future.The excellent army discussed above is the immune system in the human body. Everything explained above is done by microscopic cells unobservable to the naked eye.

How many people are aware that they have such an organized, disciplined and perfect army inside their bodies? While one is unaware of all that is going on, the cells in one's body make strenuous efforts to save one from an illness that may even bring about one's death(12 04 2014)

KONSEP DASAR IMUNOLOGI 2Pengampu :Praptiwi HAcuanmateriajar :1. Sel(limfosit) B, sel (limfosit) T, danreseptor - reseptornya2. Mayor Histocompatibility Complex MHC).

1.SEL B, SEL T, DAN RESEPTOR RESEPTORNYASel B - merupakansel yang bertanggungjawabataspembentukanImunoglobulin (Ig), - 5 15% daribesaranlimfositdalamsirkulasidarah; Jenis: sIg, pre-B, sel B memori,dll.

Gambarkerjasamasel B- dansel T.Bacteria, the Invader diusirkeluar, sebelum orang yang terinfeksi merasakan gejalanya.Sumber :www.nobelpprize.org, 2014.

GambarAcquired (Adaptive) Immunity:a. sel B, jenissertaproduk-nya : plasma danIg.b. Sel T, jenisdanresponter- hadap antigen.

Sumber : Nature Reviews,2014.

.Gambar Sel B, sel T, dan reseptor2nya.

Sumber :en.wikipedia.org, 2014.

+ Gambar Jenis imunitas Acquired (Adaptive) dan Gambar Kelas limfosit.

2. MAJOR HISTOCOMPATIBILITY COMPLEX (MHC).Major HCadalahsuatukelompokmolekulpermukaansel yang dikodeolehkeluarga gen besar, danterdapatpadasemua vertebrata. Molekul MHC memediasiinteraksi leukosit2selimundenganleukosit lain atau sel2tubuh. MHC menentukankemungkinanpenggabungandonor untuktransplantasi organ, jugakemudahanseseoranguntukterpengaruholehpenyakitautoimmunemelaluiimunisasicrossreacting.Padamanusia, MHC jugadisebuthuman leuko-cyte antigen(HLA). Dari 3 kelas MHC yang diketemukan,padaumumnyafokusdiberikanpadakelas I dan II.

MHC (HLA) kelas I memediasi kerusakan sel host yang terinfeksi atau yang ganas,melalui interaksi dengan molekul CD8 pada permukaan sel T sitotoksik. Contoh pada Gambar : Molecules of HIV.

Sumber : www.mcld.co.uk,2014.

By interacting with CD4molecules on surfaces ofhelper T cells, MHC cla

Click here to load reader

Embed Size (px)
Recommended