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CD40 signaling pathway: anti-CD40 monoclonal antibody induces rapid dephosphorylation and phosphorylation of tyrosine-phosphorylated proteins including protein tyrosine kinase Lyn, Fyn, and Syk and the appearance of a 28-kD tyrosine phosphorylated protein.
| Content Provider | Scilit |
|---|---|
| Author | Faris, M. Gaskin, F. Parsons, J. T. Fu, S. M. |
| Copyright Year | 1994 |
| Description | CD40 plays an important role in B cell activation, proliferation, and Ig class switching. The signal transduction pathway mediated by CD40 was studied using monoclonal antibody (mAb) 626.1 to CD40. Burkitt's lymphoma and Epstein-Barr virus-transformed B cell lines and tonsilar B lymphocytes were treated with the anti-CD40 mAb for various lengths of time. The early events triggered by CD40 were examined by monitoring the changes in tyrosine phosphorylation of cellular proteins with anti-phosphotyrosine mAb. Dephosphorylation of specific proteins ranging between 50-110 kD and the appearance of a 28-kD tyrosine phosphorylated protein were seen within 30 s in human B cell lines. The dephosphorylation was reversed and the 28-kD protein was dephosphorylated in cells stimulated for 1 min. In resting B cells, the appearance of the 28-kD phosphoprotein was observed in 30 s after the addition of the anti-CD40 mAb. The tyrosine phosphorylation of this protein persisted. The patterns of protein tyrosine phosphorylation differed from those induced by an anti-immunoglobulin M mAb. The changes in the state of tyrosine phosphorylation induced by the anti-CD40 mAb were obviated by mAb to CD45, a protein tyrosine phosphatase (PTP) or by the addition of sodium orthovanadate, a broad PTP inhibitor. They were also blocked by protein tyrosine kinase (PTK) inhibitors, herbimycin A and genistein, and PKC and protein serine/threonine kinase inhibitors, H7 and HA1004. In addition, the alteration in the tyrosine phosphorylation of PTKs Lyn, Fyn, and Syk was directly demonstrated. Engagement of CD40 for 30 s induced a transient decrease in tyrosine phosphorylation of these PTKs. These results indicate that the early events in CD40 signaling involve the complex interaction between PTP and protein kinases. |
| Related Links | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2191516/pdf |
| Ending Page | 1931 |
| Page Count | 9 |
| Starting Page | 1923 |
| DOI | 10.1084/jem.179.6.1923 |
| Journal | The Journal of experimental medicine |
| Issue Number | 6 |
| Volume Number | 179 |
| Language | English |
| Publisher | Rockefeller University Press |
| Publisher Date | 1994-06-01 |
| Access Restriction | Open |
| Subject Keyword | Biotechnology and Microbiology Antibody Protein Tyrosine Kinase Tyrosine Phosphorylation Anti Cd40 Journal: The Journal of experimental medicine (Vol- 179, Issue- 6) |
| Content Type | Text |
