CD59 glycoprotein, also known as MAC-inhibitory protein (MAC-IP), membrane inhibitor of reactive lysis (MIRL), or protectin, is a protein that in humans is encoded by the CD59gene.[5] It is an LU domain and belongs to the LY6/uPAR/alpha-neurotoxinprotein family.[6]
CD59 attaches to host cells via a glycophosphatidylinositol (GPI) anchor. Cholesterol-containing microdomains aid in CD59 activity by stimulating a "pinch point" in the lipid membrane during MAC assembly to prevent pore-formation and inhibit lysing.[7] When complement activation leads to deposition of C5b678 on host cells, CD59 can prevent C9 from polymerizing and forming the complement membrane attack complex.[8] It may also signal the cell to perform active measures such as endocytosis of the CD59-C9 complex.[6] Endocytosis of this complex leads to the destruction of the ion channel formation that this complex provides to the MAC. These ion channels are used for transfer of different ions to maintain the correct concentration of minerals inside and outside of the membrane, and without this correct maintenance, severe symptoms and diseases can occur such as neuron degeneration and Alzheimer's disease.[9]
Mutations affecting GPI that reduce expression of CD59 and decay-accelerating factor on red blood cells result in paroxysmal nocturnal hemoglobinuria.[10] GPI mutation and consequent reduction in CD59 expression results from a cysteine to tyrosine missense mutation, which prevents disulfide bridge formation, ultimately disrupting tertiary protein structure and preventing proper GPI-CD59 complex binding.[11]
Viruses such as HIV, human cytomegalovirus and vaccinia incorporate host cell CD59 into their own viral envelope to prevent lysis by complement.[12] Additionally, CD59 has been investigated as a target for immunotherapy when treating certain cancers such as breast cancer. Researchers have found that once CD59 had been targeted, there is an upregulation in fas and caspase-3, creating an increase in apoptosis and tumor growth suppression in MCF-7 cells.[13]
^ abMaio M, Brasoveanu LI, Coral S, Sigalotti L, Lamaj E, Gasparollo A, et al. (August 1998). "Structure, distribution, and functional role of protectin (CD59) in complement-susceptibility and in immunotherapy of human malignancies (Review)". International Journal of Oncology. 13 (2): 305–318. doi:10.3892/ijo.13.2.305. PMID9664126.
^Bohana-Kashtan O, Ziporen L, Donin N, Kraus S, Fishelson Z (July 2004). "Cell signals transduced by complement". Molecular Immunology. 41 (6–7): 583–597. doi:10.1016/j.molimm.2004.04.007. PMID15219997.
^Li B, Chu X, Gao M, Xu Y (2011). "The effects of CD59 gene as a target gene on breast cancer cells". Cellular Immunology. 272 (1): 61–70. doi:10.1016/j.cellimm.2011.09.006. PMID22000275.
Holmes CH, Simpson KL, Okada H, Okada N, Wainwright SD, Purcell DF, et al. (June 1992). "Complement regulatory proteins at the feto-maternal interface during human placental development: distribution of CD59 by comparison with membrane cofactor protein (CD46) and decay accelerating factor (CD55)". European Journal of Immunology. 22 (6): 1579–1585. doi:10.1002/eji.1830220635. PMID1376264. S2CID25836496.
Motoyama N, Okada N, Yamashina M, Okada H (October 1992). "Paroxysmal nocturnal hemoglobinuria due to hereditary nucleotide deletion in the HRF20 (CD59) gene". European Journal of Immunology. 22 (10): 2669–2673. doi:10.1002/eji.1830221029. PMID1382994. S2CID23829471.
Tone M, Walsh LA, Waldmann H (October 1992). "Gene structure of human CD59 and demonstration that discrete mRNAs are generated by alternative polyadenylation". Journal of Molecular Biology. 227 (3): 971–976. doi:10.1016/0022-2836(92)90239-G. PMID1383553.
Philbrick WM, Palfree RG, Maher SE, Bridgett MM, Sirlin S, Bothwell AL (January 1990). "The CD59 antigen is a structural homologue of murine Ly-6 antigens but lacks interferon inducibility". European Journal of Immunology. 20 (1): 87–92. doi:10.1002/eji.1830200113. PMID1689664. S2CID23636682.
Sawada R, Ohashi K, Anaguchi H, Okazaki H, Hattori M, Minato N, et al. (April 1990). "Isolation and expression of the full-length cDNA encoding CD59 antigen of human lymphocytes". DNA and Cell Biology. 9 (3): 213–220. doi:10.1089/dna.1990.9.213. PMID1692709.
Sugita Y, Tobe T, Oda E, Tomita M, Yasukawa K, Yamaji N, et al. (October 1989). "Molecular cloning and characterization of MACIF, an inhibitor of membrane channel formation of complement". Journal of Biochemistry. 106 (4): 555–557. doi:10.1093/oxfordjournals.jbchem.a122893. PMID2606909.
Bora NS, Gobleman CL, Atkinson JP, Pepose JS, Kaplan HJ (December 1993). "Differential expression of the complement regulatory proteins in the human eye". Investigative Ophthalmology & Visual Science. 34 (13): 3579–3584. PMID7505007.
Kieffer B, Driscoll PC, Campbell ID, Willis AC, van der Merwe PA, Davis SJ (April 1994). "Three-dimensional solution structure of the extracellular region of the complement regulatory protein CD59, a new cell-surface protein domain related to snake venom neurotoxins". Biochemistry. 33 (15): 4471–4482. doi:10.1021/bi00181a006. PMID7512825.
1cdq: STRUCTURE OF A SOLUBLE, GLYCOSYLATED FORM OF THE HUMAN COMPLEMENT REGULATORY PROTEIN CD59
1cdr: STRUCTURE OF A SOLUBLE, GLYCOSYLATED FORM OF THE HUMAN COMPLEMENT REGULATORY PROTEIN CD59
1cds: STRUCTURE OF A SOLUBLE, GLYCOSYLATED FORM OF THE HUMAN COMPLEMENT REGULATORY PROTEIN CD59
1erg: THREE-DIMENSIONAL SOLUTION STRUCTURE OF THE EXTRACELLULAR REGION OF THE COMPLEMENT REGULATORY PROTEIN, CD59, A NEW CELL SURFACE PROTEIN DOMAIN RELATED TO NEUROTOXINS
1erh: THREE-DIMENSIONAL SOLUTION STRUCTURE OF THE EXTRACELLULAR REGION OF THE COMPLEMENT REGULATORY PROTEIN, CD59, A NEW CELL SURFACE PROTEIN DOMAIN RELATED TO NEUROTOXINS