1
|
Identification of adaptor proteins using the ANOVA feature selection technique. Methods 2022; 208:42-47. [DOI: 10.1016/j.ymeth.2022.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 10/01/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022] Open
|
2
|
Dok-1 and Dok-2 Are Required To Maintain Herpes Simplex Virus 1-Specific CD8 + T Cells in a Murine Model of Ocular Infection. J Virol 2017; 91:JVI.02297-16. [PMID: 28490594 DOI: 10.1128/jvi.02297-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 05/02/2017] [Indexed: 12/13/2022] Open
Abstract
Dok-1 and Dok-2 negatively regulate responses downstream of several immune receptors in lymphoid and myeloid cells. Recent evidence showed that Dok proteins are essential in the formation of memory CD8+ T cells to an exogenous epitope expressed by vaccinia virus; however, the importance of Dok-1 and Dok-2 in the control of viral infection is unknown. Here, we investigated the role of Dok proteins in modulating the immune response against herpes simplex virus 1 (HSV-1) in a mouse model of ocular infection. During acute infection, viral titers in the eye were similar in wild-type (WT) and Dok-1 and Dok-2 double-knockout (DKO) mice, and the percentages of infiltrating leukocytes were similar in DKO and WT corneas and trigeminal ganglia (TG). DKO mice exhibited a diminished CD8+ T cell response to the immunodominant HSV-1 glycoprotein B (gB) epitope in the spleen and draining lymph nodes compared to WT mice during acute infection. Remarkably, gB-specific CD8+ T cells almost completely disappeared in the spleens of DKO mice during latency, and the reduction of CD8+ effector memory T (Tem) cells was more severe than that of CD8+ central memory T (Tcm) cells. The percentage of gB-specific CD8+ T cells in TG during latency was also dramatically reduced in DKO mice; however, they were phenotypically similar to those from WT mice. In ex vivo assays, reactivation was detected earlier in TG cultures from infected DKO versus WT mice. Thus, Dok-1 and Dok-2 promote survival of gB-specific CD8+ T cells in TG latently infected with HSV-1.IMPORTANCE HSV-1 establishes lifelong latency in sensory neurons of trigeminal ganglia (TG). In humans, HSV-1 is able to sporadically reactivate from latently infected neurons and establish a lytic infection at a site to which the neurons project. Most herpetic disease in humans is due to reactivation of HSV-1 from latency rather than to primary acute infection. CD8+ T cells are thought to play an important role in controlling recurrent infections. In this study, we examined the involvement of Dok-1 and Dok-2 signaling proteins in the control of HSV-1 infection. We provide evidence that Dok proteins are required to maintain a CD8+ T cell response against HSV-1 during latency-especially CD8+ Tem cells-and that they negatively affect HSV-1 reactivation from latency. Elucidating Dok-mediated mechanisms involved in the control of HSV-1 reactivation from latency might contribute to the development of therapeutic strategies to prevent recurrent HSV-1-induced pathology.
Collapse
|
3
|
Laroche-Lefebvre C, Yousefi M, Daudelin JF, Charpentier T, Tarrab E, Klinck R, Lamarre A, Labrecque N, Stäger S, Duplay P. Dok-1 and Dok-2 Regulate the Formation of Memory CD8+ T Cells. THE JOURNAL OF IMMUNOLOGY 2016; 197:3618-3627. [PMID: 27664281 DOI: 10.4049/jimmunol.1600385] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 09/06/2016] [Indexed: 11/19/2022]
Abstract
Diverse signals received by CD8+ T cells are integrated to achieve the required magnitude of cell expansion and the appropriate balance of effector/memory CD8+ T cell generation. Notably, the strength and nature of TCR signaling influence the differentiation and functional capacity of effector and memory CD8+ T cells. Dok-1 and Dok-2, the two members of the Dok family expressed in T cells, negatively regulate TCR signaling in vitro. However, the role of Dok proteins in modulating T cell function in vivo has not yet studied. We studied the function of Dok-1 and Dok-2 proteins in the regulation of the CD8+ T cell response to vaccinia virus infection. Comparison of responses to vaccinia virus expressing OVA peptide SIINFEKL by wild-type and Dok-1/2-/- CD8+ OT-I cells showed that the absence of Dok-1 and Dok-2 slightly reduced the magnitude of virus-specific effector CD8+ T cell expansion. This was not due to reduced proliferation or enhanced apoptosis of effector CD8+ T cells. Dok-1/2-deficient effector CD8+ T cells showed increased cell surface TCR expression following virus infection in vivo and increased expression of granzyme B and TNF upon stimulation with peptide Ag ex vivo. Finally, Dok-1/2-deficient effector CD8+ T had a severe defect in survival that resulted in impaired generation of memory CD8+ T cells. These results reveal the critical involvement of Dok-1 and Dok-2 in a negative-feedback loop that prevents overactivation of CD8+ T cells and promotes memory formation.
Collapse
Affiliation(s)
- Constance Laroche-Lefebvre
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada
| | - Mitra Yousefi
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada
| | - Jean-François Daudelin
- Maisonneuve-Rosemont Hospital Research Centre, University of Montreal, Montreal, Quebec H1T 2M4, Canada; and
| | - Tania Charpentier
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada
| | - Esther Tarrab
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada
| | - Roscoe Klinck
- Laboratoire de Génomique Fonctionnelle de l'Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada
| | - Alain Lamarre
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada
| | - Nathalie Labrecque
- Maisonneuve-Rosemont Hospital Research Centre, University of Montreal, Montreal, Quebec H1T 2M4, Canada; and
| | - Simona Stäger
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada
| | - Pascale Duplay
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Quebec H7V 1B7, Canada;
| |
Collapse
|
4
|
Rolland D, Basrur V, Conlon K, Wolfe T, Fermin D, Nesvizhskii AI, Lim MS, Elenitoba-Johnson KSJ. Global phosphoproteomic profiling reveals distinct signatures in B-cell non-Hodgkin lymphomas. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:1331-42. [PMID: 24667141 DOI: 10.1016/j.ajpath.2014.01.036] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/05/2013] [Accepted: 01/02/2014] [Indexed: 12/23/2022]
Abstract
Deregulation of signaling pathways controlled by protein phosphorylation underlies the pathogenesis of hematological malignancies; however, the extent to which deregulated phosphorylation may be involved in B-cell non-Hodgkin lymphoma (B-NHL) pathogenesis is largely unknown. To identify phosphorylation events important in B-NHLs, we performed mass spectrometry-based, label-free, semiquantitative phosphoproteomic profiling of 11 cell lines derived from three B-NHL categories: Burkitt lymphoma, follicular lymphoma, and mantle-cell lymphoma. In all, 6579 unique phosphopeptides, corresponding to 1701 unique phosphorylated proteins, were identified and quantified. The data are available via ProteomeXchange with identifier PXD000658. Hierarchical clustering highlighted distinct phosphoproteomic signatures associated with each lymphoma subtype. Interestingly, germinal center-derived B-NHL cell lines were characterized by phosphorylation of proteins involved in the B-cell receptor signaling. Of these proteins, phosphoprotein associated with glycosphingolipid-enriched microdomains 1 (PAG1) was identified with the most phosphorylated tyrosine peptides in Burkitt lymphoma and follicular lymphoma. PAG1 knockdown resulted in perturbation of the tyrosine phosphosignature of B-cell receptor signaling components. Significantly, PAG1 knockdown increased cell proliferation and response to antigen stimulation of these germinal center-derived B-NHLs. These data provide a detailed annotation of phosphorylated proteins in human lymphoid cancer. Overall, our study revealed the utility of unbiased phosphoproteome interrogation in characterizing signaling networks that may provide insights into pathogenesis mechanisms in B-cell lymphomas.
Collapse
Affiliation(s)
- Delphine Rolland
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Venkatesha Basrur
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Kevin Conlon
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Thomas Wolfe
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan
| | - Damian Fermin
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Alexey I Nesvizhskii
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan
| | - Megan S Lim
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Center for Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan
| | - Kojo S J Elenitoba-Johnson
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan; Center for Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan; Center for Protein Folding Disease, University of Michigan Medical School, Ann Arbor, Michigan.
| |
Collapse
|
5
|
Besin G, Yousefi M, Saba I, Klinck R, Pandolfi PP, Duplay P. Dok-1 overexpression promotes development of γδ natural killer T cells. Eur J Immunol 2012; 42:2491-504. [PMID: 22736313 DOI: 10.1002/eji.201242421] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 04/18/2012] [Accepted: 05/24/2012] [Indexed: 11/07/2022]
Abstract
In T cells, two members of the Dok family, Dok-1 and Dok-2, are predominantly expressed. Recent evidence suggests that they play a negative role in T-cell signaling. In order to define whether Dok proteins regulate T-cell development, we have generated transgenic mice overexpressing Dok-1 in thymocytes and peripheral T cells. We show that overexpression of Dok-1 retards the transition from the CD4(-) CD8(-) to CD4(+) CD8(+) stage. Moreover, there is a specific expansion of PLZF-expressing Vγ1.1(+) Vδ6.3(+) T cells. This subset of γδ T cells acquires innate characteristics including rapid IL-4 production following stimulation and requiring SLAM-associated adaptor protein (SAP) for their development. Moreover, Dok-1 overexpression promotes the generation of an innate-like CD8(+) T-cell population that expresses Eomesodermin. Altogether, these findings identify a novel role for Dok-1 in the regulation of thymic differentiation and in particular, in the development of PLZF(+) γδ T cells.
Collapse
Affiliation(s)
- Gilles Besin
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Université du Québec, Laval, Canada
| | | | | | | | | | | |
Collapse
|
6
|
Chihara K, Nakashima K, Takeuchi K, Sada K. Association of 3BP2 with SHP-1 regulates SHP-1-mediated production of TNF-α in RBL-2H3 cells. Genes Cells 2011; 16:1133-45. [DOI: 10.1111/j.1365-2443.2011.01557.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
7
|
Chen KD, Hsu LW, Goto S, Yeh CW, Nakano T, Lai CY, Chang YC, Hou CH, Wang CC, Cheng YF, Chiu KW, Lin CC, Chen CL. Adaptor protein Shc acts as an immune-regulator for the LPS-stimulated maturation of bone marrow-derived dendritic cells. BMC Immunol 2011; 12:32. [PMID: 21612602 PMCID: PMC3123310 DOI: 10.1186/1471-2172-12-32] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 05/25/2011] [Indexed: 01/10/2023] Open
Abstract
Background The Shc isoforms is known to mediate immune responses and has been indicated as a negative regulator of autoimmunity and lymphocyte activation. We aimed to evaluate the immune-regulatory role of Shc in rat bone marrow-derived DCs in the maturation process triggered by LPS. Results We found that, in response to LPS, expression of Shc proteins was induced and that neutralization of Shc inhibited the LPS-induced transient phosphorylation of p52Shc on pTyr239/240 in DCs of Lewis (LEW; RT1l) rats. Moreover, the significantly enhanced expression of IL-10 and the surface level of costimulatory molecule CD80, as well as suppressed expression of IL-6 and IL-12 in the Shc-silenced DCs were also observed. Similar IκB phosphorylation occurred in Shc-silenced DCs primed by LPS, indicating Shc is not associated with NF-κB pathway. We further demonstrate that Shc blockade on LPS-treated DCs results in significant increase of the overall STAT3 phosphorylation and the relative levels of phospho-STAT3 in the nuclear fraction. STAT3 activation by LPS with or without Shc blockade was totally abolished by SU6656, a selective Src family kinases inhibitor, underscoring the critical role of Src-mediated activation. Conclusions We conclude that Shc blockade in LPS-primed DC leads to the development of tolerogenic DC via Src-dependent STAT3 activation and that adaptor protein Shc might play a pivotal role in mediating immunogenic and tolerogenic properties of DCs.
Collapse
Affiliation(s)
- Kuang-Den Chen
- Center for Translational Research in Biomedical Sciences, Liver Transplantation Program, Department of Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Iwai LK, Benoist C, Mathis D, White FM. Quantitative phosphoproteomic analysis of T cell receptor signaling in diabetes prone and resistant mice. J Proteome Res 2010; 9:3135-45. [PMID: 20438120 DOI: 10.1021/pr100035b] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Type 1 diabetes, in human patients and NOD mice, results from an immune attack on insulin-producing beta-cells of the pancreas by autoreactive T lymphocytes. In NOD mice, genetically controlled perturbations in the signaling pathways downstream of the antigen-specific T cell receptor (TCR) may be instrumental in the altered responses of T cells, manifest as inefficient induction of apoptosis after recognition of self-antigens in the thymus or as perturbed reactivity of mature T cells in peripheral organs. To map this signaling difference(s), we have used mass spectrometry-based quantitative phosphoproteomics to compare the activation of primary CD4(+) T cells of diabetes-prone NOD and -resistant B6.H2g7 mice. Immunoprecipitation and IMAC purification of tyrosine-phosphorylated peptides, combined with a stable-isotope iTRAQ labeling, enabled us to identify and quantify over 77 phosphorylation events in 54 different proteins downstream of TCR stimulation of primary CD4(+) T cells. This analysis showed a generally higher level of phosphotyrosine in activated NOD cells, as well as several phosphorylation sites that appeared to be differentially regulated in these two strains (involving TXK, CD5, PAG1, and ZAP-70). These data highlight the differences in signaling between CD4(+) T cell compartments of NOD and B6g7 mice and may underlie the dysregulation of T cells in NOD mice.
Collapse
Affiliation(s)
- Leo K Iwai
- Department of Pathology, Harvard Medical School and Section on Immunology and Immunogenetics, Joslin Diabetes Center, Boston, Massachusetts, USA
| | | | | | | |
Collapse
|
9
|
Identification of BCAR-1 as a new substrate of Syk tyrosine kinase through a determination of amino acid sequence preferences surrounding the substrate tyrosine residue. Immunol Lett 2010; 135:151-7. [PMID: 21047529 DOI: 10.1016/j.imlet.2010.10.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/06/2010] [Accepted: 10/23/2010] [Indexed: 12/27/2022]
Abstract
Syk, a non-receptor tyrosine kinase, is an essential signaling molecule in B cells and other hematopoietic cells. Recently, its unexpected diverse functions were recognized in the regulation of cellular adhesion, innate immune recognition, vascular development, and carcinogenesis. Despite its pleiotropic role, only a few substrate proteins have been identified. To find new substrate proteins for Syk, we performed a systemic in vitro kinase assay using GST fusion peptides to determine the substrate specificity surrounding the tyrosine residue to be phosphorylated. Substitution of amino acid residues surrounding tyrosine 178 of BLNK, a principal Syk substrate in B cell receptor-mediated signaling, revealed that acidic residues at sites -5 to -1 were necessary for phosphorylation by Syk. Valine at site +1 was also influential in phosphorylation and a substitution of Pro on site +3 to a basic amino acid residue, Lys, resulted in attenuated phosphorylation. On the basis of these results, a general consensus phosphorylation motif for Syk was determined and several new candidate target proteins were identified in protein database searches. Of the candidate proteins, BCAR-1 (breast cancer anti-estrogen resistance 1) was confirmed to be phosphorylated by Syk in an in vitro kinase assay using a full-length protein of BCAR-1. Furthermore, BCAR-1 was tyrosine phosphorylated upon the overexpression of Syk in HEK-293T cells. These results suggest that more Syk substrates can be found using an in vitro kinase approach and show for the first time that BCAR-1 is a physiological substrate of Syk.
Collapse
|
10
|
Cummins TD, Barati MT, Coventry SC, Salyer SA, Klein JB, Powell DW. Quantitative mass spectrometry of diabetic kidney tubules identifies GRAP as a novel regulator of TGF-beta signaling. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1804:653-61. [PMID: 19836472 DOI: 10.1016/j.bbapap.2009.09.029] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 09/22/2009] [Accepted: 09/29/2009] [Indexed: 01/13/2023]
Abstract
The aim of this study was to define novel mediators of tubule injury in diabetic kidney disease. For this, we used state-of-the-art proteomic methods combined with a label-free quantitative strategy to define protein expression differences in kidney tubules from transgenic OVE26 type 1 diabetic and control mice. The analysis was performed with diabetic samples that displayed a pro-fibrotic phenotype. We have identified 476 differentially expressed proteins. Bioinformatic analysis indicated several clusters of regulated proteins in relevant functional groups such as TGF-beta signaling, tight junction maintenance, oxidative stress, and glucose metabolism. Mass spectrometry detected expression changes of four physiologically relevant proteins were confirmed by immunoblot analysis. Of these, the Grb2-related adaptor protein (GRAP) was up-regulated in kidney tubules from diabetic mice and fibrotic kidneys from diabetic patients, and subsequently confirmed as a novel component of TGF-beta signaling in cultured human renal tubule cells. Thus, indicating a potential novel role for GRAP in TGF-beta-induced tubule injury in diabetic kidney disease. Although we targeted a specific disease, this approach offers a robust, high-sensitivity methodology that can be applied to the discovery of novel mediators for any experimental or disease condition.
Collapse
Affiliation(s)
- Timothy D Cummins
- Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, KY, USA
| | | | | | | | | | | |
Collapse
|
11
|
Gérard A, Ghiotto M, Fos C, Guittard G, Compagno D, Galy A, Lemay S, Olive D, Nunès JA. Dok-4 is a novel negative regulator of T cell activation. THE JOURNAL OF IMMUNOLOGY 2009; 182:7681-9. [PMID: 19494292 DOI: 10.4049/jimmunol.0802203] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Dok-4 (downstream of tyrosine kinase-4) is a recently identified member of the Dok family of adaptor proteins, which are characterized by an amino-terminal pleckstrin homology domain, a phosphotyrosine-binding domain, and a carboxyl-terminal region containing several tyrosines and poly-proline-rich motifs. Two members of the Dok family, Dok-1 and Dok-2, have already been described as negative regulators in T cells. However, the function of Dok-4, which is also expressed in T cells, remains unknown. In this study, we report that Dok-4 is phosphorylated after TCR engagement and shuttled within the cytoplasm of T cells before being recruited to the polarized microtubule organizing center after the formation of the immunological synapse. Loss-of-function experiments using RNA interference constructs show that Dok-4 is a negative regulator of ERK phosphorylation, IL-2 promoter activity, and T cell proliferation. Exogenous expression of wild-type Dok-4 induces a significant activation of Rap1, which is involved in the regulation of ERK. The pleckstrin homology domain of Dok-4 is required both for its cytoplasmic shuttling and relocalization as well as for its inhibitory properties on T cell activation. Thus, Dok-4 represents a novel negative regulator of T cells.
Collapse
Affiliation(s)
- Audrey Gérard
- Unité 891, Institut National de la Santé et de la Recherche Médicale, Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Geahlen RL. Syk and pTyr'd: Signaling through the B cell antigen receptor. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:1115-27. [PMID: 19306898 DOI: 10.1016/j.bbamcr.2009.03.004] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 03/06/2009] [Indexed: 11/18/2022]
Abstract
The B cell receptor (BCR) transduces antigen binding into alterations in the activity of intracellular signaling pathways through its ability to recruit and activate the cytoplasmic protein-tyrosine kinase Syk. The recruitment of Syk to the receptor, its activation and its subsequent interactions with downstream effectors are all regulated by its phosphorylation on tyrosine. This review discusses our current understanding of how this phosphorylation regulates the activity of Syk and its participation in signaling through the BCR.
Collapse
Affiliation(s)
- Robert L Geahlen
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA.
| |
Collapse
|
13
|
Sebastian Mestel D, Beyer M, Möbs M, Steinhoff M, Sterry W, Assaf C. Zanolimumab, a human monoclonal antibody targeting CD4 in the treatment of mycosis fungoides and Sézary syndrome. Expert Opin Biol Ther 2008; 8:1929-39. [DOI: 10.1517/14712590802528696] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
14
|
Rider DA, Havenith CEG, de Ridder R, Schuurman J, Favre C, Cooper JC, Walker S, Baadsgaard O, Marschner S, vandeWinkel JGJ, Cambier J, Parren PWHI, Alexander DR. A human CD4 monoclonal antibody for the treatment of T-cell lymphoma combines inhibition of T-cell signaling by a dual mechanism with potent Fc-dependent effector activity. Cancer Res 2007; 67:9945-53. [PMID: 17942927 DOI: 10.1158/0008-5472.can-07-1148] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Zanolimumab is a human IgG1 antibody against CD4, which is in clinical development for the treatment of cutaneous and nodal T-cell lymphomas. Here, we report on its mechanisms of action. Zanolimumab was found to inhibit CD4+ T cells by combining signaling inhibition with the induction of Fc-dependent effector mechanisms. First, T-cell receptor (TCR) signal transduction is inhibited by zanolimumab through a fast, dual mechanism, which is activated within minutes. Ligation of CD4 by zanolimumab effectively inhibits early TCR signaling events but, interestingly, activates signaling through the CD4-associated tyrosine kinase p56lck. An uncoupling of p56lck from the TCR by anti-CD4 allows the kinase to transmit direct inhibitory signals via the inhibitory adaptor molecules Dok-1 and SHIP-1. Second, CD4+ T cells are killed by induction of antibody-dependent cell-mediated cytotoxicity, to which CD45RO+ cells are more sensitive than CD45RA+ cells. Finally, zanolimumab induces down-modulation of CD4 from cell surfaces via a slow Fc-dependent mechanism. In conclusion, zanolimumab rapidly inhibits T-cell signaling via a dual mechanism of action combined with potent Fc-dependent lysis of CD4+ T cells and may act long-term by down-regulating CD4.
Collapse
MESH Headings
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized
- Antibody-Dependent Cell Cytotoxicity
- CD3 Complex/immunology
- CD4 Antigens/biosynthesis
- CD4 Antigens/genetics
- CD4 Antigens/immunology
- CD4 Lymphocyte Count
- CD4-Positive T-Lymphocytes/drug effects
- CD4-Positive T-Lymphocytes/immunology
- Double-Blind Method
- Down-Regulation
- Humans
- Inositol Polyphosphate 5-Phosphatases
- Lymphocyte Activation/drug effects
- Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/metabolism
- Lymphoma, T-Cell, Cutaneous/immunology
- Lymphoma, T-Cell, Cutaneous/therapy
- Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases
- Phosphoric Monoester Hydrolases/metabolism
- Phosphorylation
- Psoriasis/immunology
- Psoriasis/therapy
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- Signal Transduction/drug effects
Collapse
Affiliation(s)
- David A Rider
- Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
Cbl proteins are ubiquitin ligases and multifunctional adaptor proteins that are implicated in the regulation of signal transduction in various cell types and in response to different stimuli. Cbl-associated proteins can assemble together at a given time or space inside the cell, and such an interactome can form signal competent networks that control many physiological processes. Dysregulation of spatial or temporal constraints in the Cbl interactome results in the development of human pathologies such as immune diseases, diabetes and cancer.
Collapse
Affiliation(s)
- Mirko H H Schmidt
- Institute for Biochemistry II, Goethe University Medical School, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany
| | | |
Collapse
|
16
|
Pan Z, Shen Y, Ge B, Du C, McKeithan T, Chan WC. Studies of a germinal centre B-cell expressed gene, GCET2, suggest its role as a membrane associated adapter protein. Br J Haematol 2007; 137:578-90. [PMID: 17489982 PMCID: PMC2396194 DOI: 10.1111/j.1365-2141.2007.06597.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
GCET2 (Germinal centre B-cell expressed transcript 2; also named HGAL) is a newly cloned gene that has been shown to be a useful marker for germinal centre (GC) B cells and GC B-cell derived malignancies, including follicular lymphomas and germinal centre B cell-like diffuse large B-cell lymphomas (GCB-DLBCLs), and is a useful prognosticator for DLBCLs. We report here the biochemical and biological properties of GCET2, which may help to determine its role in the GC reaction. GCET2 is constitutively localised in the plasma membrane but is excluded from lipid rafts. GCET2 does not have a transmembrane domain, and its membrane localisation is mediated by myristoylation and palmitoylation. GCET2 has five conserved putative tyrosine phosphorylation sites, and it can be phosphorylated following pervanadate treatment in B cells. By serially mutating the five tyrosines, the third and fourth tyrosines were found to be essential for GCET2 phosphorylation. GCET2 was phosphorylated when co-transfected into COS7 cells with protein tyrosine kinases (PTKs) LYN, LCK or SYK, and therefore it could be a substrate of these kinases in B cells. The third tyrosine site ((107)YENV) of GCET2 is a consensus GRB2 binding site, and GCET2 was found to associate with GRB2 through the third tyrosine following phosphorylation. Our data suggests that GCET2 may be an adaptor protein in GC B cells that transduces signals from GC B-cell membrane to the cytosol via its association with GRB2.
Collapse
MESH Headings
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- B-Lymphocytes/metabolism
- Base Sequence
- Binding Sites
- COS Cells
- Cell Line, Tumor
- Cell Membrane/metabolism
- Chlorocebus aethiops
- GRB2 Adaptor Protein/metabolism
- Germinal Center/metabolism
- Humans
- Immunoblotting
- Intracellular Signaling Peptides and Proteins
- Lymphoma, Follicular/metabolism
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/metabolism
- Mice
- Microfilament Proteins
- Microscopy, Confocal
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Neoplasm Proteins/genetics
- Neoplasm Proteins/metabolism
- Phosphorylation
- Protein-Tyrosine Kinases/metabolism
- Sequence Alignment
- Transduction, Genetic/methods
- Transfection/methods
- Vanadates/pharmacology
Collapse
Affiliation(s)
- Zenggang Pan
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | | | | | | | | | | |
Collapse
|
17
|
Barr VA, Balagopalan L, Barda-Saad M, Polishchuk R, Boukari H, Bunnell SC, Bernot KM, Toda Y, Nossal R, Samelson LE. T-Cell Antigen Receptor-Induced Signaling Complexes: Internalization Via a Cholesterol-Dependent Endocytic Pathway. Traffic 2006; 7:1143-62. [PMID: 16919152 DOI: 10.1111/j.1600-0854.2006.00464.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
T-cell antigen receptor engagement causes the rapid assembly of signaling complexes. The adapter protein SLP-76, detected as SLP-yellow fluorescent protein, initially clustered with the TCR and other proteins, then translocated medially on microtubules. As shown by total internal reflection fluorescence microscopy and the inhibition of SLP-76 movement at 16 degrees C, this movement required endocytosis. Immunoelectron microscopy showed SLP-76 staining of smooth pits and tubules. Cholesterol depletion decreased the movement of SLP-76 clusters, as did coexpression of the ubiquitin-interacting motif domain from eps15. These data are consistent with the internalization of SLP-76 via a lipid raft-dependent pathway that requires interaction of the endocytic machinery with ubiquitinylated proteins. The endocytosed SLP-76 clusters contained phosphorylated SLP-76 and phosphorylated LAT. The raft-associated, transmembrane protein LAT likely targets SLP-76 to endocytic vesicles. The endocytosis of active SLP-76 and LAT complexes suggests a possible mechanism for downregulation of signaling complexes induced by TCR activation.
Collapse
Affiliation(s)
- Valarie A Barr
- Laboratory of Cellular and Molecular Biology, Department of Health and Human Services, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Herrin BR, Justement LB. Expression of the adaptor protein hematopoietic Src homology 2 is up-regulated in response to stimuli that promote survival and differentiation of B cells. THE JOURNAL OF IMMUNOLOGY 2006; 176:4163-72. [PMID: 16547253 DOI: 10.4049/jimmunol.176.7.4163] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Analysis of hematopoietic Src homology 2 (HSH2) protein expression in mouse immune cells demonstrated that it is expressed at low levels in resting B cells but not T cells or macrophages. However, HSH2 expression is up-regulated within 6-12 h in response to multiple stimuli that promote activation, differentiation, and survival of splenic B cells. HSH2 expression is increased in response to anti-CD40 mAb, the TLR ligands LPS and CpG DNA, and B lymphocyte stimulator (BLyS), a key regulator of peripheral B cell survival and homeostasis. Stimulation of B cells with anti-CD40 mAb, LPS, CpG DNA, or BLyS has previously been shown to induce activation of NF-kappaB. In agreement with this finding, up-regulation of HSH2 expression in response to these stimuli is blocked by inhibitors of NF-kappaB activation and is potentiated by stimulation with PMA, suggesting that HSH2 expression is dependent on NF-kappaB activation. In contrast to CD40, BAFF receptor, TLR4, and TLR9 mediated signaling, stimulation of splenic B cells via the BCR was not observed to induce expression of HSH2 unless the cells had been stimulated previously through CD40. Finally, HSH2 expression is down-regulated in splenic B cells in response to stimulation with IL-21, which has been shown to induce apoptosis, even in the presence of anti-CD40 mAb, LPS, or CpG DNA. IL-21 stimulation also results in down-regulation of antiapoptotic proteins such as Bcl-x(L) and up-regulation of proapoptotic proteins like Bim. Therefore, HSH2 expression is coordinately up-regulated with known antiapoptotic molecules and directly correlates with B cell survival.
Collapse
Affiliation(s)
- Brantley R Herrin
- Division of Developmental and Clinical Immunology, Department of Microbiology, University of Alabama, Birmingham, 35294, USA
| | | |
Collapse
|
19
|
Han J, Shui JW, Zhang X, Zheng B, Han S, Tan TH. HIP-55 is important for T-cell proliferation, cytokine production, and immune responses. Mol Cell Biol 2005; 25:6869-78. [PMID: 16055701 PMCID: PMC1190228 DOI: 10.1128/mcb.25.16.6869-6878.2005] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Engagement of the T-cell receptor (TCR) triggers a series of signaling events that lead to the activation of T cells. HIP-55 (SH3P7 or mAbp1), an actin-binding adaptor protein, interacts with and is tyrosine phosphorylated by ZAP-70, which is a crucial proximal protein tyrosine kinase for TCR signaling. HIP-55 is important for JNK and HPK1 activation induced by TCR signaling. In this study, we report the generation and characterization of HIP-55 knockout mice. We found that HIP-55 knockout mice were viable and fertile but showed decreased body weight and increased occurrence of death within the first 4 weeks after birth. The lymphoid organs in HIP-55 knockout mice showed cellularity and T-cell development comparable to that of the wild-type mice. HIP-55 knockout T cells displayed defective T-cell proliferation, decreased cytokine production, and decreased up-regulation of the activation markers induced by TCR stimulation. TCR internalization was slightly increased in HIP-55 knockout T cells. These phenotypes were accompanied by reduced immune responses, including antigen-specific antibody production and T-cell proliferation in HIP-55 knockout mice. The TCR-induced signaling events, including LAT/phospholipase Cgamma1 phosphorylation and HPK1/JNK activation, were partially defective in HIP-55 knockout T cells. These results demonstrate the importance of HIP-55 as an adaptor protein in the TCR signaling and immune system.
Collapse
MESH Headings
- Actins/chemistry
- Alleles
- Animals
- Blotting, Southern
- Blotting, Western
- Body Weight
- Cell Proliferation
- Cytokines/biosynthesis
- Cytokines/metabolism
- Dose-Response Relationship, Drug
- Flow Cytometry
- Humans
- Immune System
- Immunoprecipitation
- Jurkat Cells
- Lymphocyte Activation
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microfilament Proteins/metabolism
- Microfilament Proteins/physiology
- Models, Genetic
- Mutation
- Phospholipase C gamma
- Phosphorylation
- Polymerase Chain Reaction
- Protein Binding
- Protein Structure, Tertiary
- Protein-Tyrosine Kinases/chemistry
- RNA/metabolism
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction
- T-Lymphocytes/cytology
- Time Factors
- Type C Phospholipases/metabolism
- Tyrosine/chemistry
- ZAP-70 Protein-Tyrosine Kinase
- src Homology Domains/physiology
Collapse
Affiliation(s)
- Jin Han
- Department of Immunology, Baylor College of Medicine, Houston, Texas 77030.
| | | | | | | | | | | |
Collapse
|
20
|
Allam A, Marshall AJ. Role of the adaptor proteins Bam32, TAPP1 and TAPP2 in lymphocyte activation. Immunol Lett 2005; 97:7-17. [PMID: 15626471 DOI: 10.1016/j.imlet.2004.09.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2004] [Revised: 09/28/2004] [Accepted: 09/29/2004] [Indexed: 01/13/2023]
Abstract
Adaptor proteins play critical roles in lymphocyte activation by mediating intermolecular interactions and assembling signaling complexes at the activated plasma membrane. Bam32/DAPP1 and the related adaptor proteins TAPP1 and TAPP2 were identified by multiple groups about 5 years ago and considerable progress has been made in elucidating the structure, interaction partners and function of these molecules. These cytoplasmic adaptor proteins are recruited to the plasma membrane through interaction of their PH domains with the lipid products of phosphatidylinositol 3-kinases. They share a unique mode of regulation in that they bind with high affinity to phosphatidylinositol-3,4-bisphosphate and their recruitment is enhanced rather than inhibited by the lipid phosphatase SHIP. Two knockout mouse studies and several gain-and-loss of function studies in cell lines have recently been published, demonstrating multiple functions of Bam32 in B cell activation. Bam32 is required for biological responses including B cell antigen receptor (BCR)-induced proliferation and antibody responses to type II T-independent antigens. Bam32 regulates multiple BCR signaling events including activation of the mitogen activated protein kinases ERK and JNK, remodeling of the actin cytoskeleton through the GTPase Rac1 and BCR internalization. Several studies have emerged suggesting that TAPP1 and TAPP2 may play roles in B and T cell activation; however, the biological functions regulated by these molecules remain to be defined. Here we will comprehensively review the available data on the structure and function of Bam32, TAPP1 and TAPP2 and present an integrated working model for Bam32 function in B cell activation and a general model for distinct effector pathways of PI 3-kinases.
Collapse
Affiliation(s)
- Atef Allam
- Department of Immunology, University of Manitoba, 611 Basic Medical Sciences Building, 730 William Avenue, Winnipeg, Man., R3E-0W3, Canada
| | | |
Collapse
|
21
|
Harnett MM, Katz E, Ford CA. Differential signalling during B-cell maturation. Immunol Lett 2005; 98:33-44. [PMID: 15790506 DOI: 10.1016/j.imlet.2004.11.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2004] [Revised: 11/04/2004] [Accepted: 11/07/2004] [Indexed: 11/30/2022]
Abstract
The molecular mechanism by which the antigen receptors (BCR) on B cells can elicit differential maturation state-specific responses is one of the central problems in B-cell differentiation yet to be resolved. Indeed, many of the early signalling events detected following BCR ligation, such as activation of protein tyrosine kinases (PTK), phospholipase C (PLC), phosphoinositide-3-kinase (PI 3K), protein kinase C (PKC) and the RasMAPK (mitogen activating protein kinase) signalling cascades are observed throughout B-cell maturation. However, it is becoming clear that the differential functional responses of these BCR-coupled signals observed during B-cell maturation are dependent on a number of parameters including signal strength and duration, subcellular localisation of the signal, maturation-restricted expression of downstream signalling effector elements/isoforms and modulation of signal by co-receptors. Thus, the combined signature of BCR signalling is likely to dictate the functional response and act as a developmental checkpoint for B-cell maturation.
Collapse
Affiliation(s)
- Margaret M Harnett
- Division of Immunology, Infection and Inflammation, University of Glasgow, Glasgow G116NT, UK.
| | | | | |
Collapse
|
22
|
Razzaq TM, Ozegbe P, Jury EC, Sembi P, Blackwell NM, Kabouridis PS. Regulation of T-cell receptor signalling by membrane microdomains. Immunology 2004; 113:413-26. [PMID: 15554919 PMCID: PMC1782593 DOI: 10.1111/j.1365-2567.2004.01998.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2004] [Revised: 09/09/2004] [Accepted: 09/15/2004] [Indexed: 01/04/2023] Open
Abstract
There is now considerable evidence suggesting that the plasma membrane of mammalian cells is compartmentalized by functional lipid raft microdomains. These structures are assemblies of specialized lipids and proteins and have been implicated in diverse biological functions. Analysis of their protein content using proteomics and other methods revealed enrichment of signalling proteins, suggesting a role for these domains in intracellular signalling. In T lymphocytes, structure/function experiments and complementary pharmacological studies have shown that raft microdomains control the localization and function of proteins which are components of signalling pathways regulated by the T-cell antigen receptor (TCR). Based on these studies, a model for TCR phosphorylation in lipid rafts is presented. However, despite substantial progress in the field, critical questions remain. For example, it is unclear if membrane rafts represent a homogeneous population and if their structure is modified upon TCR stimulation. In the future, proteomics and the parallel development of complementary analytical methods will undoubtedly contribute in further delineating the role of lipid rafts in signal transduction mechanisms.
Collapse
Affiliation(s)
- Tahir M Razzaq
- Bone and Joint Research Unit, William Harvey Research Institute, Queen Mary's School of Medicine and Dentistry, Queen Mary's College, London
| | | | | | | | | | | |
Collapse
|
23
|
Miah SMS, Hatani T, Qu X, Yamamura H, Sada K. Point mutations of 3BP2 identified in human-inherited disease cherubism result in the loss of function. Genes Cells 2004; 9:993-1004. [PMID: 15507112 DOI: 10.1111/j.1365-2443.2004.00784.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Adaptor protein 3BP2 positively regulates the high affinity IgE receptor (FcepsilonRI)-mediated activation of degranulation in mast cells. Genetic study identified the point mutations of 3BP2 gene in human-inherited disease cherubism. The multiple cysts in cherubism lesion of jaw bones are filled with the activated osteoclasts and stromal cells, including mast cells. By over-expression study using rat basophilic leukaemia RBL-2H3 mast cells, we have analysed the effect of the point mutations on the function of 3BP2 protein, which plays a positive regulatory role on FcepsilonRI-mediated mast cell activation. Over-expression of 3BP2 mutants suppressed the antigen-induced degranulation and cytokine gene transcription. Antigen-induced phosphorylation of Vav1, activation of Rac1, extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen activated protein kinase (MAPK), inhibitor of nuclear factor kappaB kinase (IKK) and nuclear factor of activated T cells (NFAT) were all impaired in the cells over-expressing the cherubism mutants of 3BP2. Furthermore, cherubism mutations of 3BP2 may abrogate the binding ability to interact with chaperone protein 14-3-3. These results demonstrate that over-expression of the mutant form of 3BP2 inhibits the antigen-induced mast cell activation. It suggests that point mutations of 3BP2 gene cause the dysfunction of 3BP2 in vivo.
Collapse
Affiliation(s)
- S M Shahjahan Miah
- Division of Proteomics, Department of Genome Sciences, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | | | | | | | | |
Collapse
|
24
|
Janssen E, Zhu M, Craven B, Zhang W. Linker for Activation of B Cells: A Functional Equivalent of a Mutant Linker for Activation of T Cells Deficient in Phospholipase C-γ1 Binding. THE JOURNAL OF IMMUNOLOGY 2004; 172:6810-9. [PMID: 15153499 DOI: 10.4049/jimmunol.172.11.6810] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adaptor proteins have important functions in coupling stimulation through immunoreceptors with downstream events. The adaptor linker for activation of B cells (LAB)/non-T cell activation linker (NTAL) is expressed in various immune cell types and has a similar domain structure as linker for activation of T cells (LAT). In this study we generated a LAB transgenic mouse to compare the functional differences between LAB and LAT. A LAB transgene expressed in LAT-deficient T cells was able to restore T cell development. However, these mice developed severe organomegaly with disorganized lymphoid tissues. Lymphocytes from these transgenic mice were hyperactivated, and T cells produced large amounts of type II cytokines. In addition, these activities appeared to be uncoupled from the TCR. An examination of the signaling capabilities of these T cells revealed that LAB resembled a LAT molecule unable to bind phospholipase C-gamma1.
Collapse
Affiliation(s)
- Erin Janssen
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | | |
Collapse
|
25
|
Lymphocyte activation. Curr Opin Immunol 2003. [DOI: 10.1016/s0952-7915(03)00051-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|