> For the complete documentation index, see [llms.txt](https://thisispiggy.gitbook.io/my-wiki/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://thisispiggy.gitbook.io/my-wiki/01-step-1/immunology/03-b-cells.md). # 03 B Cells [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/B%20cell%20function,%20histology/README.md).. ![](https://i.imgur.com/A2zyFOR.jpg) ## BCR [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/BCR%20components/README.md).. ![](https://i.imgur.com/1fwbEZG.jpg) * FAB: fragment antigen binding * FC: constant * Made of monomer IgM antibody ![](https://i.imgur.com/dyO6NT8.jpg) * purple: variable regions. Vary from 1 B cell to another * light chain: 1 constant region; heavy chain 3 constant regions * variable regions end in nitrogen groups; constant end in carboxyl group * Connected by disulfide bridges * macrophage Fc/protein A binds CH2-CH3 region ### Heavy chain [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/BCR%20made%20how/README.md).. ![](https://i.imgur.com/y2z2gYH.jpg) ## Activation [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/2%20ways%20of%20B%20cell%20activation/README.md).. ![](https://i.imgur.com/oxVfk7C.jpg) [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/T%20Dependent%20B%20activation%20process/README.md).. ![](https://i.imgur.com/4cfprgr.jpg) 1. B cell crosslinked by antigen 2. Second signal required in addition to crosslinking 3. MHC 2 binds TCR and CD4 4. CD40 binds CD40L: class switching 5. B7 binds CD28: T cytokine secretion ![](https://i.imgur.com/i5b5QLG.jpg) [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/T%20dependent%20B%20activation%20via%20macrophage%20process/README.md).. ![](https://i.imgur.com/1JjQLH3.jpg) * macrophage antigen presenting instead ### T Independent [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/T%20independent%20B%20activation%20process.%20Why%20is%20this%20process%20important.%20Comparison%20with%20T%20dependent).. ![](https://i.imgur.com/3akFi8f.jpg) * so many antigen on surface, B cell activated without T [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/T%20dependent%20vs%20independent%20B%20activation/README.md).. ![](https://i.imgur.com/RrAh4pr.jpg) ### Conjugated Vaccine [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/Conjugated%20vaccine%20why,%20examples/README.md).. ![](https://i.imgur.com/DA4OSvs.jpg) ![](https://i.imgur.com/ACgfNmh.jpg) ## Surface Proteins [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/B%20surface%20proteins,%20functions/README.md).. ![](https://i.imgur.com/lujcvb1.jpg) * CD21 receptor for complement, receptor for EBV ## Antibody [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/3%20different%20shapes%20of%20antibodies/README.md).. ![](https://i.imgur.com/RxxJjBn.jpg) [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/Antibody%203%20functions/README.md).. ![](https://i.imgur.com/gCTQ0p5.jpg) ### Protein A [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/Protein%20A%20bacteria,%20function/README.md).. ![](https://i.imgur.com/lRLA8sB.jpg) * prevents opsonization: ![](https://i.imgur.com/7sEsfpd.jpg) ### Class Switching [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/B%20class%20switch%20process,%20triggers/README.md).. ![](https://i.imgur.com/KtWItuK.jpg) * only change Fc portion, not FAB portion ![](https://i.imgur.com/XAy53KN.jpg) * Cm and Cd closes * Cm and Cd spliced out; B starts to make Cy (IgG), Ca, Ce ### IgM [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/IgM%20functions,%20good%20for,%20bad%20for,%20complement?%20Cross%20placenta?/README.md).. ![](https://i.imgur.com/pBviPSN.jpg) * Classical pathway: 2 C1 molecules bind together to Fc of IgM; easy to bind because so many IgM Fc together * Prevents attachment: very large and clumps on to pathogens * Weak opsonin: too big; macrophages can't get to Fc ### IgG [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/IgG%20function,%20good%20for,%20placenta?/README.md).. ![](https://i.imgur.com/bXte5WE.jpg) * macrophages bind to Fc very easily ![](https://i.imgur.com/X1Hoj3l.jpg) ### IgA [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/IgA%20function,%20monomer%20vs%20dimer%20when,%20complement?%20Why%20are%20they%20good%20for%20mucosal%20infections?/README.md).. ![](https://i.imgur.com/NhdPoTh.jpg) * secretory component in middle of 2 IgA * linked by secretory: can't complement ![](https://i.imgur.com/GRq5CQz.jpg) ![](https://i.imgur.com/e8DEvuP.jpg) ### IgA Protease [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/IgA%20protease%20bacteria/README.md).. ![](https://i.imgur.com/BSs1OgZ.jpg) ### IgE [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/IgE%20binds,%20complement?%20pathogenesis%20for%20allergy/README.md).. ![](https://i.imgur.com/1TGHjRn.jpg) ![](https://i.imgur.com/rRbRPff.jpg) ## Somatic Hypermutation [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/somatic%20hypermutation%20is,%20process,%20when%20does%20it%20happen/README.md).. ![](https://i.imgur.com/11Zxg0l.jpg) * Happens during proliferation after activation * Stronger binding will proliferate the most ![](https://i.imgur.com/xNp1VUU.jpg) ## B Cell Fate [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/B%20cell%20fate/README.md).. ![](https://i.imgur.com/lfbpZzH.jpg) ![](https://i.imgur.com/Kbraux3.jpg) ## Development Timeline [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/B%20cell%20development%20timeline%20and%20location/README.md).. ![](https://i.imgur.com/gxWzpI1.jpg) ## Vaccines [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/2%20types%20of%20vaccines/README.md).. * active * passive ### Active [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/Active%20vaccines%20function,%20types/README.md).. ![](https://i.imgur.com/o1HPdOJ.jpg) [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/live%20attenuated%20vs%20killed/README.md).. ![](https://i.imgur.com/qFfnmuH.jpg) * Live attenuated: T cell mediated response * Killed: antibodies against HA antigens of virus * Inactivated viral vaccines do not infect host cells and therefore do not enter the MHC class I antigen-processing pathway, which is normally required for the generation of a significant CD8+ cell-mediated immune response. In contrast, live-attenuated viral vaccines strongly stimulate the MHC class I antigen-processing pathway and can generate cytotoxic CD8+ T lymphocytes that kill infected cells. [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/oral%20vs%20IM%20vaccines/README.md).. ![](https://i.imgur.com/0riB2l8.jpg) ### Passive [\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Immunology/passive%20vaccines%20are,%20time,%20memory,%20examples/README.md).. ![](https://i.imgur.com/ozbdHnz.jpg) * give if suspicion for rabies, tetanus: neutralize before infection happens --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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