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1.
HLA ; 102(1): 108-109, 2023 07.
Article in English | MEDLINE | ID: mdl-36908228

ABSTRACT

A novel HLA-DRB1*04 allele, officially designated HLA-DRB1*04:361, was identified by next-generation sequencing.


Subject(s)
High-Throughput Nucleotide Sequencing , Humans , HLA-DRB1 Chains/genetics , Alleles
2.
HLA ; 101(2): 170-171, 2023 02.
Article in English | MEDLINE | ID: mdl-36205591

ABSTRACT

A novel HLA-B*51 allele, officially designated HLA-B*51:371, was identified by next-generation sequencing.


Subject(s)
HLA-B Antigens , High-Throughput Nucleotide Sequencing , Humans , Base Sequence , Alleles , HLA-B Antigens/genetics
3.
HLA ; 97(3): 232-233, 2021 03.
Article in English | MEDLINE | ID: mdl-33124768

ABSTRACT

Identification of the novel HLA-B*27 null allele officially designated HLA-B*27:225N.


Subject(s)
Genes, MHC Class I , HLA-B Antigens , Alleles , Base Sequence , HLA-B Antigens/genetics , Humans , Sequence Analysis, DNA
4.
Brain Behav Immun ; 81: 608-616, 2019 10.
Article in English | MEDLINE | ID: mdl-31344493

ABSTRACT

OBJECTIVE: Obsessive-compulsive disorder (OCD) is a debilitating neuropsychiatric disorder with an etiopathophysiology that seems to include immune alterations. Previous studies have suggested that variations in the levels of circulating T cell subpopulations may be involved in psychiatric diseases. However, the role of these cells in OCD remains unexplored. Hence, the present study aimed to examine the levels of T helper 1 (Th1), Th2, Th17 and regulatory T (Treg) cells in patients with early-onset OCD and healthy controls. METHODS: The assessment was performed in 99 children and adolescents with OCD and 46 control subjects. The percentages of circulating Th1, Th2, Th17 and Treg cells were evaluated using flow cytometry. RESULTS: OCD patients had significantly higher levels of Th17 cells and lower percentages of Treg cells than healthy controls (p = 0.001 and p = 0.005, respectively). Furthermore, levels of Th17 cells progressively increased with the duration (p = 0.005) and severity of OCD (p = 0.008), whereas the percentages of Treg cells significantly declined with the duration of the disorder (p = 1.8 × 10-5). CONCLUSIONS: These results provide more evidence of the involvement of immune dysregulation, specifically an imbalance in the levels of circulating T helper and regulatory T cells, in the pathophysiology of early-onset OCD.


Subject(s)
Obsessive-Compulsive Disorder/immunology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Adolescent , Cytokines/immunology , Female , Flow Cytometry/methods , Humans , Male , Obsessive-Compulsive Disorder/metabolism , T-Lymphocytes, Regulatory/metabolism , Th1 Cells/immunology , Th17 Cells/metabolism , Th2 Cells/immunology
5.
Clin Rheumatol ; 38(9): 2529-2539, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31020474

ABSTRACT

INTRODUCTION: Research describes higher incidence of neurodevelopmental disorders and learning disabilities in offspring of women affected by lupus. Factors implied are pregnancy and delivery adversities and exposure to maternal antibodies and cytokines. Little is known about the offspring immunological condition or the relation between offspring and maternal condition. OBJECTIVES: This study was conducted in order to analyze immunological configuration, psychopathology, and neuropsychological performance of young offspring of women with lupus, in comparison with healthy controls and in relation to maternal psychophysical condition. METHODS: Twenty-one offspring aged 8-17 of 17 women with lupus and 34 controls were recruited. Pregnancy conditions, stress factors, and immunological, psychopathological, and neuropsychological characteristics were compared. Immunological tests included standard lupus screening, lupus-related autoantibodies, antibodies against GluN2 subunit of the N-methyl-D-aspartate receptor (NMDAR) (anti-DWEYS Ab), and levels of ten cytokines (IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, GMCSF, IFN-γ, TNF-α). RESULTS: Offspring had lower leukocyte count (p = 0.001) and higher levels of anti-dsDNA Ab (p = 0.022), anti-DWEYS-GluN2 Ab (p < 0.001), and eight cytokines (IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-10, TNF-α-all p < 0.001-and IFN-γ, p = 0.026) than controls. Their cytokine levels did not differ from their mothers'; 23.9% of offspring met the criteria for a clinical psychiatric diagnosis. No differences were found in intelligence measures. Various neuropsychological scores correlated inversely with maternal psychophysical health. CONCLUSIONS: Offspring's profile suggests proinflammatory and autoimmune activation. Their rate of psychiatric diagnosis appears higher than in the general population, and their cognitive performance is related to maternal psychophysical health. Longitudinal research might investigate whether immunological and psychosocial conditions influence psychopathology and cognition. Graphical abstract The hypothesized sequence for physical and neuropsychological development for the SLE offspring.


Subject(s)
Autoantibodies/blood , Child of Impaired Parents , Cognition Disorders/diagnosis , Cytokines/blood , Lupus Erythematosus, Systemic , Prenatal Exposure Delayed Effects/diagnosis , Adolescent , Child , Cognition Disorders/blood , Female , Humans , Male , Pregnancy , Prenatal Exposure Delayed Effects/blood , Prenatal Exposure Delayed Effects/psychology
6.
Hum Immunol ; 80(7): 449-460, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30844424

ABSTRACT

Extended molecular characterization of HLA genes in the IHWG reference B-lymphoblastoid cell lines (B-LCLs) was one of the major goals for the 17th International HLA and Immunogenetics Workshop (IHIW). Although reference B-LCLs have been examined extensively in previous workshops complete high-resolution typing was not completed for all the classical class I and class II HLA genes. To address this, we conducted a single-blind study where select panels of B-LCL genomic DNA samples were distributed to multiple laboratories for HLA genotyping by next-generation sequencing methods. Identical cell panels comprised of 24 and 346 samples were distributed and typed by at least four laboratories in order to derive accurate consensus HLA genotypes. Overall concordance rates calculated at both 2- and 4-field allele-level resolutions ranged from 90.4% to 100%. Concordance for the class I genes ranged from 91.7 to 100%, whereas concordance for class II genes was variable; the lowest observed at HLA-DRB3 (84.2%). At the maximum allele-resolution 78 B-LCLs were defined as homozygous for all 11 loci. We identified 11 novel exon polymorphisms in the entire cell panel. A comparison of the B-LCLs NGS HLA genotypes with the HLA genotypes catalogued in the IPD-IMGT/HLA Database Cell Repository, revealed an overall allele match at 68.4%. Typing discrepancies between the two datasets were mostly due to the lower-resolution historical typing methods resulting in incomplete HLA genotypes for some samples listed in the IPD-IMGT/HLA Database Cell Repository. Our approach of multiple-laboratory NGS HLA typing of the B-LCLs has provided accurate genotyping data. The data generated by the tremendous collaborative efforts of the 17th IHIW participants is useful for updating the current cell and sequence databases and will be a valuable resource for future studies.


Subject(s)
B-Lymphocytes/virology , HLA Antigens/genetics , Herpesvirus 4, Human/immunology , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class I/genetics , Histocompatibility Testing/methods , Alleles , Cell Line, Transformed , Cell Transformation, Viral , Data Accuracy , Exons/genetics , Genetic Loci , Genetic Variation , Genotype , Haplotypes/genetics , High-Throughput Nucleotide Sequencing/methods , Histocompatibility , Homozygote , Humans , Sequence Analysis, DNA/methods , Single-Blind Method
7.
Hum Immunol ; 80(4): 228-236, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30738112

ABSTRACT

The 17th International HLA and Immunogenetics Workshop (IHIW) organizers conducted a Pilot Study (PS) in which 13 laboratories (15 groups) participated to assess the performance of the various sequencing library preparation protocols, NGS platforms and software in use prior to the workshop. The organizers sent 50 cell lines to each of the 15 groups, scored the 15 independently generated sets of NGS HLA genotyping data, and generated "consensus" HLA genotypes for each of the 50 cell lines. Proficiency Testing (PT) was subsequently organized using four sets of 24 cell lines, selected from 48 of 50 PS cell lines, to validate the quality of NGS HLA typing data from the 34 participating IHIW laboratories. Completion of the PT program with a minimum score of 95% concordance at the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 loci satisfied the requirements to submit NGS HLA typing data for the 17th IHIW projects. Together, these PS and PT efforts constituted the 17th IHIW Quality Control project. Overall PT concordance rates for HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1, HLA-DRB1, HLA-DRB3, HLA-DRB4 and HLA-DRB5 were 98.1%, 97.0% and 98.1%, 99.0%, 98.6%, 98.8%, 97.6%, 96.0%, 99.1%, 90.0% and 91.7%, respectively. Across all loci, the majority of the discordance was due to allele dropout. The high cost of NGS HLA genotyping per experiment likely prevented the retyping of initially failed HLA loci. Despite the high HLA genotype concordance rates of the software, there remains room for improvement in the assembly of more accurate consensus DNA sequences by NGS HLA genotyping software.


Subject(s)
Genotype , HLA Antigens/genetics , High-Throughput Nucleotide Sequencing/methods , Histocompatibility Testing/methods , Immunogenetics , Alleles , Consensus Development Conferences as Topic , Humans , International Cooperation , Pilot Projects , Quality Control , Software
8.
Mol Ther Methods Clin Dev ; 12: 134-144, 2019 Mar 15.
Article in English | MEDLINE | ID: mdl-30623002

ABSTRACT

Genetically modifying autologous T cells to express an anti-CD19 chimeric antigen receptor (CAR) has shown impressive response rates for the treatment of CD19+ B cell malignancies in several clinical trials (CTs). Making this treatment available to our patients prompted us to develop a novel CART19 based on our own anti-CD19 antibody (A3B1), followed by CD8 hinge and transmembrane region, 4-1BB- and CD3z-signaling domains. We show that A3B1 CAR T cells are highly cytotoxic and specific against CD19+ cells in vitro, inducing secretion of pro-inflammatory cytokines and CAR T cell proliferation. In vivo, A3B1 CAR T cells are able to fully control disease progression in an NOD.Cg-Prkdc scid Il2rd tm1Wjl /SzJ (NSG) xenograph B-ALL mouse model. Based on the pre-clinical data, we conclude that our CART19 is clearly functional against CD19+ cells, to a level similar to other CAR19s currently being used in the clinic. Concurrently, we describe the implementation of our CAR T cell production system, using lentiviral vector and CliniMACS Prodigy, within a medium-sized academic institution. The results of the validation phase show our system is robust and reproducible, while maintaining a low cost that is affordable for academic institutions. Our model can serve as a paradigm for similar institutions, and it may help to make CAR T cell treatment available to all patients.

9.
World J Biol Psychiatry ; 20(5): 352-358, 2019 06.
Article in English | MEDLINE | ID: mdl-28562177

ABSTRACT

Objective: The exact aetiology of obsessive-compulsive disorder (OCD) is unknown, although there is evidence to suggest a gene-environment interaction model. Several lines of evidence support a possible role of the immune system in this model. Methods: The present study explores the allele variability in HLA genes of class II (HLA-DRB1, HLA-DQB1) in a sample of 144 early-onset OCD compared with reference samples of general population in the same geographical area. Results: None of the 39 alleles identified (allele frequency >1%) showed significant differences between OCD and reference populations. Pooling the different alleles that comprised HLA-DR4 (including DRB1*04:01, DRB1*04:04 and DRB1*04:05 alleles) we observed a significantly higher frequency (X21 = 5.53, P = 0.018; OR = 1.64, 95% CI 1.08-2.48) of these alleles in the early-onset OCD sample (10.8%) than in the reference population (6.8%). Conclusions: Taking into account the role of HLA class II genes in the central nervous system, the results presented here support a role of the immune system in the pathophysiological model of OCD.


Subject(s)
Alleles , Genes, MHC Class II , HLA-DQ beta-Chains/genetics , HLA-DRB1 Chains/genetics , Obsessive-Compulsive Disorder/genetics , Adolescent , Age of Onset , Child , Databases, Factual , Female , Gene Frequency , Haplotypes , Humans , Male , Obsessive-Compulsive Disorder/immunology , Spain
10.
J Neuroinflammation ; 14(1): 261, 2017 Dec 28.
Article in English | MEDLINE | ID: mdl-29284508

ABSTRACT

BACKGROUND: Although the exact etiology of obsessive-compulsive disorder (OCD) is unknown, there is growing evidence of a role for immune dysregulation in the pathophysiology of the disease, especially in the innate immune system including the microglia. To test this hypothesis, we studied inflammatory markers in monocytes from pediatric patients with OCD and from healthy controls. METHODS: We determined the percentages of total monocytes, CD16+ monocytes, and classical (CD14highCD16-), intermediate (CD14highCD16low), and non-classical (CD14lowCD16high) monocyte subsets in 102 patients with early-onset OCD and in 47 healthy controls. Moreover, proinflammatory cytokine production (GM-CSF, IL-1ß, IL-6, IL-8, and TNF-α) was measured by multiplex Luminex analysis in isolated monocyte cultures, in basal conditions, after exposure to lipopolysaccharide (LPS) to stimulate immune response or after exposure to LPS and the immunosuppressant dexamethasone. RESULTS: OCD patients had significantly higher percentages of total monocytes and CD16+ monocytes than healthy controls, mainly due to an increase in the intermediate subset but also in the non-classical monocytes. Monocytes from OCD patients released higher amounts of GM-CSF, IL-1ß, IL-6, IL-8, and TNF-α than healthy controls after exposure to LPS. However, there were no significant differences in basal cytokine production or the sensitivity of monocytes to dexamethasone treatment between both groups. Based on monocyte subset distribution and cytokine production after LPS stimulation, patients receiving psychoactive medications seem to have an intermediate inflammatory profile, that is, lower than non-medicated OCD individuals and higher than healthy controls. CONCLUSIONS: These results strongly support the involvement of an enhanced proinflammatory innate immune response in the etiopathogenesis of early-onset OCD.


Subject(s)
Cytokines/metabolism , Inflammation/metabolism , Monocytes/metabolism , Obsessive-Compulsive Disorder/metabolism , Adolescent , Child , Dexamethasone/pharmacology , Female , Glucocorticoids/pharmacology , Humans , Lipopolysaccharides/pharmacology , Male , Monocytes/drug effects , Young Adult
11.
Psychoneuroendocrinology ; 62: 233-42, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26325024

ABSTRACT

OBJECTIVE: The role of inflammation in psychopathology has received great attention over the past decades. Immune system dysfunction and altered cytokine levels have been reported in most psychiatric disorders in adults. Few data are available regarding children and adolescents (C&A), or regarding the relationship between cytokine levels and psychosocial stress. This study investigates the profile of the most described cytokines in a sample of C&A inpatients affected by an acute psychiatric condition requiring hospitalization, in comparison with healthy subjects, as well as possible associations between psychosocial stressors and psychopathology and/or cytokine concentrations. METHODS: Patients with a diagnosis of Affective, Anxiety, Adjustment, Psychotic, Obsessive-Compulsive, Tic or Tourette Disorders were consecutively recruited from our clinic between June 2010 and February 2012. Controls were recruited from the same geographic area. All subjects were between 8 and 17 years old. Twelve cytokines are compared: interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL_10, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IFN-γ-induced protein-10 (IP-10), monocyte chemoattractant protein (MCP)-1. Psychosocial stress was measured through the Stressful Life Events Scale, Child and Parents versions (SLES-C and SLES-P) and the evaluation of the family integrity. RESULTS: One hundred and eleven subjects (77C&A inpatients and 34 healthy controls), of which 54 were males (49%), with a median (interquartile range) age of 16 (13.7-17.3) years, were included in this study. IL-1ß, IL6, IL8, IP-10, MCP-1 and monocytes were found to be significantly higher in the patient group (p<0.05). Differences were confirmed when adjusting by BMI, age, gender and drug intake at admission for all cytokines except MCP-1. IL-8 and IL-1ß were also higher throughout the different diagnostic categories, than in control group (p<0.05). Stress measures were higher in patients. A significant correlation was found between stress measured by the SLES and some inflammatory markers: SLES_C with IL-1ß, IL-8, MCP-1, and SLES_P with IL-1ß and monocytes absolute and relative counts (Spearman's r between 0.219 and 0.297, p<0.05). Logistic regression identified the following variables as independent predictors of the patient condition, (odds ratio per quartile, p-value): IL8 (1, 0.9, 12.1, 32.0, p=0.044), IP10 (1, 14.1, 2.5, 3.7, p=0.044), monocyte absolute count (1, 1.1, 6.0, 19.4, p=0.030). CONCLUSIONS: Results show elevated inflammation markers from the innate immune system across C&A acute psychiatric diagnosis, and suggest a link between psychopathology, inflammation and stress. Inflammatory markers resulted predictors of patient status. These exploratory results are coherent with current psychoneuroimmunology and neurodevelopmental investigations.


Subject(s)
Immunity, Innate/physiology , Interleukin-8/blood , Mental Disorders/blood , Adolescent , Biomarkers/blood , Child , Cytokines/blood , Female , Humans , Inflammation/blood , Inflammation/immunology , Male , Mental Disorders/immunology
12.
J Immunol ; 186(4): 2344-54, 2011 Feb 15.
Article in English | MEDLINE | ID: mdl-21217009

ABSTRACT

The scavenger receptor cysteine-rich superfamily (SRCR-SF) members are transmembrane and/or secreted receptors exhibiting one or several repeats of a cysteine-rich protein module of ∼100 aa, named scavenger receptor cysteine-rich (SRCR). Two types of SRCR domains (A or B) have been reported, which differ in the number of coding exons and intradomain cysteines. Although no unifying function has been reported for SRCR-SF members, recognition of pathogen-associated molecular patterns (PAMPs) was recently shown for some of them. In this article, we report the structural and functional characterization of mouse S5D-SRCRB, a new group B member of the SRCR-SF. The s5d-srcrb gene maps at mouse chromosome 7 and encompasses 14 exons extending over 15 kb. The longest cDNA sequence found is 4286 bp in length and encodes a mature protein of 1371 aa, with a predicted M(r) of 144.6 kDa. Using an episomal mammalian-expression system, a glycosylated soluble recombinant form >200 kDa was obtained and used as immunogen for the generation of specific rat mAbs. Subsequent immunohistochemical and real-time PCR analysis showed significant S5D-SRCRB expression in murine genitourinary and digestive tracts. S5D-SRCRB was shown to bind endogenous extracellular matrix proteins (laminin and galectin-1), as well as PAMPs present on Gram-positive and Gram-negative bacteria and fungi. PAMP binding by S5D-SRCRB induced microbial aggregation and subsequent inhibition of PAMP-induced cytokine release. These abilities suggest that S5D-SRCRB might play a role in the innate defense and homeostasis of certain specialized epithelial surfaces.


Subject(s)
Cysteine/metabolism , Gene Expression Regulation/immunology , Multigene Family/immunology , Scavenger Receptors, Class B/chemistry , Scavenger Receptors, Class B/physiology , Amino Acid Sequence , Animals , Epithelial Cells/chemistry , Epithelial Cells/metabolism , Epithelial Cells/physiology , HEK293 Cells , Homeostasis/genetics , Homeostasis/immunology , Humans , Immunity, Innate/genetics , Male , Mice , Mice, Inbred C57BL , Molecular Sequence Data , Protein Binding/immunology , Protein Structure, Tertiary/genetics , Rats , Rats, Sprague-Dawley , Receptors, Pattern Recognition/chemistry , Receptors, Pattern Recognition/metabolism , Receptors, Pattern Recognition/physiology , Scavenger Receptors, Class B/biosynthesis , Scavenger Receptors, Class B/genetics
13.
J Immunol ; 177(2): 1152-9, 2006 Jul 15.
Article in English | MEDLINE | ID: mdl-16818773

ABSTRACT

CD6 is a cell surface receptor primarily expressed on immature thymocytes and mature T and B1a lymphocytes. Through its binding to activated leukocyte cell adhesion molecule (ALCAM/CD166), CD6 is considered to play an important role in lymphocyte development and activation. Accordingly, CD6 associates with the TCR/CD3 complex and colocalizes with it at the center of the mature immunological synapse on T lymphocytes. Moreover, the CD6-ALCAM interaction has been shown to be critical for proper immunological synapse maturation and T cell proliferative responses. However, the precise biological effects of CD6 ligation and its signaling pathway are still not well understood. The present study shows that CD6 ligation with three different specific mAbs (161.8, SPV-L14.2, and MAE1-C10) induces time- and dose-dependent activation of ERK1/2 on normal and leukemic human T cells. This effect was also observed upon CD6 ligation with a chimerical ALCAM protein (ALCAM-Fc). The C-terminal cytoplasmic region of CD6, as well as Src tyrosine kinases, was critical for CD6-induced ERK1/2 activation. Synergistic effects were observed upon coligation of the TCR/CD3 complex with CD6. The ligation of CD6 induced the transcriptional activation of reporter genes under the control of the c-Fos serum responsive element and AP-1. Accordingly, CD6-mediated activation of p38 and JNK was also observed. These findings indicate that the CD6-ALCAM interaction results in activation of the three MAPK cascades, likely influencing the dynamic balance that determines whether resting or activated lymphocytes survive or undergo apoptosis.


Subject(s)
Antigens, CD/physiology , Antigens, Differentiation, T-Lymphocyte/physiology , MAP Kinase Signaling System/immunology , Activated-Leukocyte Cell Adhesion Molecule/metabolism , Activated-Leukocyte Cell Adhesion Molecule/physiology , Antibodies, Monoclonal/metabolism , Antigens, CD/immunology , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/immunology , Antigens, Differentiation, T-Lymphocyte/metabolism , Apoptosis/immunology , CD3 Complex/immunology , CD3 Complex/metabolism , Cell Line, Tumor , Cell Survival/immunology , Cytoplasm/chemistry , Cytoplasm/immunology , Cytoplasm/metabolism , Enzyme Activation/immunology , Enzyme Induction/immunology , Humans , Jurkat Cells , Leukemia/enzymology , Leukemia/immunology , Leukemia/pathology , Ligands , Mitogen-Activated Protein Kinase 1/biosynthesis , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/biosynthesis , Mitogen-Activated Protein Kinase 3/metabolism , Peptide Fragments/physiology , T-Lymphocytes/cytology , T-Lymphocytes/enzymology , T-Lymphocytes/pathology , Up-Regulation/immunology , src-Family Kinases/physiology
15.
Biochemistry ; 44(48): 15715-24, 2005 Dec 06.
Article in English | MEDLINE | ID: mdl-16313174

ABSTRACT

The LAR transmembrane tyrosine phosphatase associates with liprin-alpha proteins and colocalizes with liprin-alpha1 at focal adhesions. LAR has been implicated in axon guidance, and liprins are involved in synapse formation and synapse protein trafficking. Several liprin mutants have weaker binding to LAR as assessed by yeast interaction trap assays, and the extents of in vitro and in vivo phosphorylation of these mutants were reduced relative to that of wild-type liprin-alpha1. Treatment of liprin-alpha1 with calf intestinal phosphatase weakened its interaction with the recombinant GST-LAR protein. A liprin LH region mutant that inhibited liprin phosphorylation did not bind to LAR as assessed by coprecipitation studies. Endogenous LAR was shown to bind phosphorylated liprin-alpha1 from MDA-486 cells labeled in vivo with [32P]orthophosphate. In further characterizing the phosphorylation of liprin, we found immunoprecipitates of liprin-alpha1 expressed in COS-7 cells to incorporate phosphate after washes of up to 4 M NaCl. Additionally, purified liprin-alpha1 derived from Sf-9 insect cells retained the ability to incorporate phosphate in in vitro phosphorylation assays, and a liprin-alpha1 truncation mutant incorporated phosphate after denaturation and/or renaturation in SDS gels. Finally, binding assays showed that liprin binds to ATP-agarose and that the interaction is challenged by free ATP, but not by free GTP. Moreover, liprin LH region mutations that inhibit liprin phosphorylation stabilized the association of liprin with ATP-agarose. Taken together, our results suggest that liprin autophosphorylation regulates its association with LAR.


Subject(s)
Nerve Tissue Proteins/metabolism , Phosphoproteins/metabolism , Protein Tyrosine Phosphatases/metabolism , Receptors, Cell Surface/metabolism , Adaptor Proteins, Signal Transducing , Amino Acid Sequence , Humans , Membrane Proteins/biosynthesis , Molecular Sequence Data , Phosphoproteins/genetics , Phosphorylation , Receptor-Like Protein Tyrosine Phosphatases, Class 2 , Sequence Alignment
16.
J Immunol ; 175(3): 1406-14, 2005 Aug 01.
Article in English | MEDLINE | ID: mdl-16034076

ABSTRACT

CD6 is a type I membrane glycoprotein expressed on thymocytes, mature T and B1a lymphocytes, and CNS cells. CD6 binds to activated leukocyte cell adhesion molecule (CD166), and is considered as a costimulatory molecule involved in lymphocyte activation and thymocyte development. Accordingly, CD6 partially associates with the TCR/CD3 complex and colocalizes with it at the center of the mature immunological synapse (IS) on T lymphocytes. However, the signaling pathway used by CD6 is still mostly unknown. The yeast two-hybrid system has allowed us the identification of syntenin-1 as an interacting protein with the cytoplasmic tail of CD6. Syntenin-1 is a PDZ (postsynaptic density protein-95, postsynaptic discs large, and zona occludens-1) domain-containing protein, which functions as an adaptor protein able to bind cytoskeletal proteins and signal transduction effectors. Mutational analyses showed that certain amino acids of the most C-terminal sequence of CD6 (-YDDISAA) and the two postsynaptic density protein-95, postsynaptic discs large, and zona occludens-1 domains of syntenin-1 are relevant to the interaction. Further confirmation of the CD6-syntenin-1 interaction was obtained from pull-down and co-immunoprecipitation assays in mammalian cells. Image analyses also showed that syntenin-1 accumulates at CD6 caps and at the IS. Therefore, we propose that syntenin-1 may function as a scaffolding protein coupling CD6 and most likely other lymphocyte receptors to cytoskeleton and/or signaling effectors during IS maturation.


Subject(s)
Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Carrier Proteins/metabolism , Membrane Proteins/metabolism , Protein Interaction Mapping , Amino Acid Sequence , Animals , Antigens, CD/genetics , Antigens, Differentiation, T-Lymphocyte/genetics , COS Cells , Carrier Proteins/genetics , Cell Line, Tumor , Chlorocebus aethiops , Cytoplasm/immunology , Cytoplasm/metabolism , Humans , Immunoprecipitation , Jurkat Cells , Membrane Proteins/genetics , Mice , Molecular Sequence Data , Protein Interaction Mapping/methods , Protein Structure, Tertiary , Syntenins , T-Lymphocytes/metabolism , Transfection , Two-Hybrid System Techniques
17.
J Biol Chem ; 278(15): 13265-70, 2003 Apr 11.
Article in English | MEDLINE | ID: mdl-12551902

ABSTRACT

The Trio guanine nucleotide exchange factor functions in neural development in Caenorhabditis elegans and Drosophila and in the development of neural tissues and skeletal muscle in mouse. The association of Trio with the Lar tyrosine phosphatase led us to study the role of tyrosine phosphorylation in Trio function using focal adhesion kinase (FAK). The Lar-interacting domain of Trio is constitutively tyrosine-phosphorylated when expressed in COS-7 cells and was highly phosphorylated when it was co-transfected with FAK. Co-precipitation studies indicated that Trio binds to the FAK amino-terminal domain and to the FAK kinase domain via its SH3 and kinase domains, respectively. Tyrosine-phosphorylated FAK and Trio were present mainly in the detergent-insoluble fraction of cell lysates, and co-expression of Trio and FAK resulted in increased amounts of Trio present in the detergent-insoluble fraction. Immunofluorescence of cells co-transfected with FAK and Trio revealed significant co-localization of the proteins at the cell periphery, indicating that they form a stable complex in vivo. A FAK phosphorylation site, tyrosine residue 2737, was identified in subdomain I of the Trio kinase domain. Additionally, in vitro phosphorylation assays and in vivo co-expression studies indicated that Trio enhances FAK kinase activity. These results suggest Trio may be involved in the regulation of focal adhesion dynamics in addition to effecting changes in the actin cytoskeleton through the activation of Rho family GTPases.


Subject(s)
Drosophila Proteins , Guanine Nucleotide Exchange Factors , Phosphoproteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/metabolism , Signal Transduction/physiology , Animals , Binding Sites , COS Cells , Caenorhabditis elegans , Chlorocebus aethiops , Drosophila , Focal Adhesion Kinase 1 , Focal Adhesion Protein-Tyrosine Kinases , HeLa Cells , Humans , Mice , Muscle, Skeletal/physiology , Mutagenesis , Phosphorylation , Recombinant Proteins/metabolism , Sequence Deletion , Transfection , src Homology Domains
18.
Neuron ; 34(1): 39-52, 2002 Mar 28.
Article in English | MEDLINE | ID: mdl-11931740

ABSTRACT

Interaction with the multi-PDZ protein GRIP is required for the synaptic targeting of AMPA receptors, but the underlying mechanism is unknown. We show that GRIP binds to the liprin-alpha/SYD2 family of proteins that interact with LAR receptor protein tyrosine phosphatases (LAR-RPTPs) and that are implicated in presynaptic development. In neurons, liprin-alpha and LAR-RPTP are enriched at synapses and coimmunoprecipitate with GRIP and AMPA receptors. Dominant-negative constructs that interfere with the GRIP-liprin interaction disrupt the surface expression and dendritic clustering of AMPA receptors in cultured neurons. Thus, by mediating the targeting of liprin/GRIP-associated proteins, liprin-alpha is important for postsynaptic as well as presynaptic maturation.


Subject(s)
Carrier Proteins/metabolism , Nerve Tissue Proteins/metabolism , Phosphoproteins/metabolism , Protein Tyrosine Phosphatases , Receptors, AMPA/metabolism , Adaptor Proteins, Signal Transducing , Animals , Brain/cytology , Brain/metabolism , COS Cells , Cells, Cultured , Embryo, Mammalian , Intracellular Signaling Peptides and Proteins , Neurons/metabolism , Neurons/ultrastructure , Rats , Receptor-Like Protein Tyrosine Phosphatases, Class 2 , Receptors, Cell Surface/metabolism , Synapses/metabolism , Synapses/ultrastructure
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