IntAct European Bioinformatics Institute IntAct intact http://www.ebi.ac.uk/ http://www.ebi.ac.uk/intact/query/${ac} EBI-[0-9]+|IA:[0-9]+ INTerAction database (IntAct) provides an open source database and toolkit for the storage, presentation and analysis of molecular interactions. http://www.ebi.ac.uk/intact European Bioinformatics Institute; Wellcome Trust Genome Campus; Hinxton, Cambridge; CB10 1SD; United Kingdom http://www.ebi.ac.uk/intact/ Adhesion of human T cells to antigen-presenting cells through SIRPbeta2-CD47 interaction costimulates T-cell proliferation. Adhesion of human T cells to antigen-presenting cells through SIRPbeta2-CD47 interaction costimulates T-cell proliferation. Blood (0006-4971) 2005 Piccio L., Vermi W., Boles KS., Fuchs A., Strader CA., Facchetti F., Cella M., Colonna M. mcolonna@pathology.wustl.edu 07-Aug-2007: Contacted by JYOTI. human-jurkat Homo sapiens jurkat Human T cell leukemia facs fluorescence-activated cell sorting FACS Flow cytometry facs antibody detection identification by antibody antibody detection Piccio L., Vermi W., Boles KS., Fuchs A., Strader CA., Facchetti F., Cella M., Colonna M. mcolonna@pathology.wustl.edu Accepted 2007-AUG-26 by JYOTI. Blood (0006-4971) 2005 cd47_human Leukocyte surface antigen CD47 CD47 MER6 Integrin-associated protein Antigenic surface determinant protein OA3 Protein MER6 protein protein human Homo sapiens Human MWPLVAALLLGSACCGSAQLLFNKTKSVEFTFCNDTVVIPCFVTNMEAQNTTEVYVKWKFKGRDIYTFDGALNKSTVPTDFSSAKIEVSQLLKGDASLKMDKSDAVSHTGNYTCEVTELTREGETIIELKYRVVSWFSPNENILIVIFPIFAILLFWGQFGIKTLKYRSGGMDEKTIALLVAGLVITVIVIVGAILFVPGEYSLKNATGLGLIVTSTGILILLHYYVFSTAIGLTSFVIAILVIQVIAYILAVVGLSLCIAACIPMHGPLLISGLSILALAQLLGLVYMKFVASNQKTIQPPRKAVEEPLNAFKESKGMMNDE 5D20730A2632D550 sirpg_human Signal-regulatory protein gamma SIRPG SIRPB2 Signal-regulatory protein beta-2 CD172 antigen-like family member B protein protein human Homo sapiens Human MPVPASWPHPPGPFLLLTLLLGLTEVAGEEELQMIQPEKLLLVTVGKTATLHCTVTSLLPVGPVLWFRGVGPGRELIYNQKEGHFPRVTTVSDLTKRNNMDFSIRISSITPADVGTYYCVKFRKGSPENVEFKSGPGTEMALGAKPSAPVVLGPAARTTPEHTVSFTCESHGFSPRDITLKWFKNGNELSDFQTNVDPTGQSVAYSIRSTARVVLDPWDVRSQVICEVAHVTLQGDPLRGTANLSEAIRVPPTLEVTQQPMRVGNQVNVTCQVRKFYPQSLQLTWSENGNVCQRETASTLTENKDGTYNWTSWFLVNISDQRDDVVLTCQVKHDGQLAVSKRLALEVTVHQKDQSSDATPGPASSLTALLLIAVLLGPIYVPWKQKT 0F5099BE1DE35AC8 sirpg-cd47 1 2 unspecified role unspecified role prey prey human-jurkat Homo sapiens jurkat Human T cell leukemia 3 unspecified role unspecified role bait bait c-terminal d1d2-igg fusion protein fusion protein c-term range C-terminal range c-term range c-term range C-terminal range c-term range human-293 Homo sapiens transformed primary embryonal kidney cells Human 293 Transformed human primary embryonal kidney cells. The Cell type named 293 is synonymous with HEK-293. physical association physical association Sirpg-D1D2-IgG was found to bind to T-cells expressing CD47, by flow cytometry. The binding was totally blocked by anti-CD47 mAbs, and partially inhibited by anti-Sirpg mAbs. This demonstrates that Sirpg is a receptor for CD47. Importantly, binding of SIRPb2-D1D2-IgG to Jurkat consistently yielded a lower median fluorescence intensity than did binding of SIRPb2-D1D2-IgG in flow cytometry, suggesting that the affinity of SIRPb2 for CD47 is lower that that of SIRPa(Figure 5). Figure 5 sirpg-cd47-1 1 2 unspecified role unspecified role prey prey human-jurkat Homo sapiens jurkat Human T cell leukemia 3 unspecified role unspecified role bait bait mouse-bw Mus musculus carcinoma cells most probably hepatoma bw mouse carcinoma cells most probably hepatoma physical association physical association Sirpg-expressing BW cells were able to conjugate with CD47-expressing Jurkat cells and this cojugation was partially blocked by anti-Sirp and anti-CD47 antibodies but not by anti-CD18 or anti-CD11a antibodies, suggesting that Sirpg-CD47 interaction significantly contributes to adhesion of T-cells to cells expressing CD47. we hypothesized that SIRPb2 may be involved in cell-cell adhesion rather than inhibitory or activating signaling. To test this, we mixed BW cells transfected with SIRPb2(BW-SIRPb2) with Jurkat or Jurkat-CD470. After 30 minutes of incubation at 37�C we measured formation of conjugates by 2-color flow cytometry. Under these conditions, BW-SIRPb2 made abundant conjugates with Jurkat but not with Jurkat-CD470 (Figure 6A). Conjugate formation was partially blocked by anti-SIRP and anti-CD47 antibodies, confirming the specificity of the interaction. In contrast, antibodies against CD18 (Figure 6A) or CD11a (data not shown) did not significantly block cell conjugation, suggesting that SIRP 2-CD47 interaction mediates cell conjugation by a mechanism that is independent of leukocyte function�associated molecule-1 (LFA-1). To corroborate that SIRP 2-CD47 interaction mediates cell-cell adhesion, we compared the ability of Jurkat, which expresses both CD47 and SIRP 2, and JurkatCD470, which expresses only SIRP 2, to form conjugates either alone or in combination with each other. Jurkat-CD470 formed fewer conjugates with itself than when mixed with Jurkat, and fewer than Jurkat formed with itself (Figure 6B). Figure 6A, 6B.