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Kilbourne AM, Almirall D, Goodrich DE, Lai Z, Abraham KM, Nord KM, Bowersox NW. Enhancing outreach for persons with serious mental illness: 12-month results from a cluster randomized trial of an adaptive implementation strategy. Implement Sci 2014; 9:163. [PMID: 25544027 PMCID: PMC4296543 DOI: 10.1186/s13012-014-0163-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 10/21/2014] [Indexed: 12/21/2022] Open
Abstract
Background Few implementation strategies have been empirically tested for their effectiveness in improving uptake of evidence-based treatments or programs. This study compared the effectiveness of an immediate versus delayed enhanced implementation strategy (Enhanced Replicating Effective Programs (REP)) for providers at Veterans Health Administration (VA) outpatient facilities (sites) on improved uptake of an outreach program (Re-Engage) among sites not initially responding to a standard implementation strategy. Methods One mental health provider from each U.S. VA site (N = 158) was initially given a REP-based package and training program in Re-Engage. The Re-Engage program involved giving each site provider a list of patients with serious mental illness who had not been seen at their facility for at least a year, requesting that providers contact these patients, assessing patient clinical status, and where appropriate, facilitating appointments to VA health services. At month 6, sites considered non-responsive (N = 89, total of 3,075 patients), defined as providers updating documentation for less than <80% of patients on their list, were randomized to two adaptive implementation interventions: Enhanced REP (provider coaching; N = 40 sites) for 6 months followed by Standard REP for 6 months; versus continued Standard REP (N = 49 sites) for 6 months followed by 6 months of Enhanced REP for sites still not responding. Outcomes included patient-level Re-Engage implementation and utilization. Results Patients from sites that were randomized to receive Enhanced REP immediately compared to Standard REP were more likely to have a completed contact (adjusted OR = 2.13; 95% CI: 1.09–4.19, P = 0.02). There were no differences in patient-level utilization between Enhanced and Standard REP sites. Conclusions Enhanced REP was associated with greater Re-Engage program uptake (completed contacts) among sites not responding to a standard implementation strategy. Further research is needed to determine whether national implementation of Facilitation results in tangible changes in patient-level outcomes. Trial registration ISRCTN: ISRCTN21059161 Electronic supplementary material The online version of this article (doi:10.1186/s13012-014-0163-3) contains supplementary material, which is available to authorized users.
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Birgenheir DG, Ilgen MA, Bohnert ASB, Abraham KM, Bowersox NW, Austin K, Kilbourne AM. Authors' response to the letter to the editor: "Pain in primary care patients with bipolar disorder". Gen Hosp Psychiatry 2014; 36:229. [PMID: 24359679 DOI: 10.1016/j.genhosppsych.2013.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 11/19/2013] [Indexed: 11/19/2022]
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Abraham KM, Ganoczy D, Yosef M, Resnick SG, Zivin K. Receipt of employment services among Veterans Health Administration users with psychiatric diagnoses. ACTA ACUST UNITED AC 2014; 51:401-14. [DOI: 10.1682/jrrd.2013.05.0114] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 10/21/2013] [Indexed: 11/05/2022]
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Kilbourne AM, Abraham KM, Goodrich DE, Bowersox NW, Almirall D, Lai Z, Nord KM. Cluster randomized adaptive implementation trial comparing a standard versus enhanced implementation intervention to improve uptake of an effective re-engagement program for patients with serious mental illness. Implement Sci 2013; 8:136. [PMID: 24252648 PMCID: PMC3874628 DOI: 10.1186/1748-5908-8-136] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 11/14/2013] [Indexed: 11/17/2022] Open
Abstract
Background Persons with serious mental illness (SMI) are disproportionately burdened by premature mortality. This disparity is exacerbated by poor continuity of care with the health system. The Veterans Health Administration (VA) developed Re-Engage, an effective population-based outreach program to identify veterans with SMI lost to care and to reconnect them with VA services. However, such programs often encounter barriers getting implemented into routine care. Adaptive designs are needed when the implementation intervention requires augmentation within sites that do not initially respond to an initial implementation intervention. This protocol describes the methods used in an adaptive implementation design study that aims to compare the effectiveness of a standard implementation strategy (Replicating Effective Programs, or REP) with REP enhanced with External Facilitation (enhanced REP) to promote the uptake of Re-Engage. Methods/Design This study employs a four-phase, two-arm, longitudinal, clustered randomized trial design. VA sites (n = 158) across the United States with a designated Re-Engage provider, at least one Veteran with SMI lost to care, and who received standard REP during a six-month run-in phase. Subsequently, 88 sites with inadequate uptake were stratified at the cluster level by geographic region (n = 4) and VA regional service network (n = 20) and randomized to REP (n = 49) vs. enhanced REP (n = 39) in phase two. The primary outcome was the percentage of veterans on each facility outreach list documented on an electronic web registry. The intervention was at the site and network level and consisted of standard REP versus REP enhanced by external phone facilitation consults. At 12 months, enhanced REP sites returned to standard REP and 36 sites with inadequate participation received enhanced REP for six months in phase three. Secondary implementation outcomes included the percentage of veterans contacted directly by site providers and the percentage re-engaged in VA health services. Discussion Adaptive implementation designs consisting of a sequence of decision rules that are tailored based on a site’s uptake of an effective program may produce more relevant, rapid, and generalizable results by more quickly validating or rejecting new implementation strategies, thus enhancing the efficiency and sustainability of implementation research and potentially leading to the rollout of more cost-efficient implementation strategies. Trial registration Current Controlled Trials
ISRCTN21059161.
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Birgenheir DG, Ilgen MA, Bohnert ASB, Abraham KM, Bowersox NW, Austin K, Kilbourne AM. Pain conditions among veterans with schizophrenia or bipolar disorder. Gen Hosp Psychiatry 2013; 35:480-4. [PMID: 23639185 DOI: 10.1016/j.genhosppsych.2013.03.019] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/15/2013] [Accepted: 03/26/2013] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The purpose of this study was to assess the rates of chronic, noncancer pain conditions in patients with schizophrenia or bipolar disorder within the Veterans Health Administration (VHA) System. METHOD This cross-sectional study used administrative data extracted from VHA treatment records of all individuals receiving VHA services in fiscal year 2008 (N=5,195,551). The associations between severe psychiatric disorders (schizophrenia and bipolar disorder) and chronic pain (arthritis, back pain, chronic pain, migraine, headache, psychogenic and neuropathic) were evaluated using a series of logistic regression analyses. RESULTS Veterans with schizophrenia [odds ratio (OR)=1.21] and bipolar disorder (OR=2.17) were significantly more likely to have chronic pain overall relative to veterans without these psychiatric conditions. These associations were slightly lower than for the association between depression and pain in this sample (OR=2.61). The highest associations between specific psychiatric diagnosis and pain condition were found with chronic pain, headache and psychogenic pain. CONCLUSIONS Noncancer pain conditions occur in elevated rates among patients with schizophrenia and bipolar disorder. Future research could further examine possible barriers to adequate pain treatment among people with serious mental illness, as well as the extent to which chronic pain might impact mental health recovery.
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Abraham KM, Lai Z, Bowersox NW, Goodrich DE, Visnic S, Burk JP, Kilbourne AM. Health care utilization prior to loss to care among veterans with serious mental illness. Psychiatr Serv 2013; 64:594-6. [PMID: 23728603 DOI: 10.1176/appi.ps.002382012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE This study examined the association between utilization of Veterans Affairs (VA) health services and the probability of treatment dropout among veterans with serious mental illness. METHODS Utilization of VA health services in the fiscal year (FY) before treatment dropout among veterans with serious mental illness who were lost to care for at least 12 months beginning in FYs 2008 or 2009 (N=6,687) was compared with utilization in FYs 2007 or 2008 among veterans with serious mental illness who remained in care (N=6,687). RESULTS The veterans (mean age=54) were predominantly male (91%) and Caucasian (76%). After accounting for demographic and clinical variables, the analyses found that more primary care and mental health outpatient visits and fewer general medical and mental health hospitalizations were associated with lower odds of dropout. CONCLUSIONS Engagement in outpatient health care was associated with lower odds of loss to care among veterans with serious mental illness.
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Miller CJ, Abraham KM, Bajor LA, Lai Z, Kim HM, Nord KM, Goodrich DE, Bauer MS, Kilbourne AM. Quality of life among patients with bipolar disorder in primary care versus community mental health settings. J Affect Disord 2013; 146:100-5. [PMID: 22981021 PMCID: PMC3554842 DOI: 10.1016/j.jad.2012.08.045] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 08/27/2012] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Bipolar disorder is associated with functional impairment across a number of domains, including health-related quality of life (HRQOL). Many patients are treated exclusively in primary care (PC) settings, yet little is known how HRQOL outcomes compare between PC and community mental health (CMH) settings. This study aimed to explore the correlates of HRQOL across treatment settings using baseline data from a multisite, randomized controlled trial for adults with bipolar disorder. METHODS HRQOL was measured using the SF-12 physical (PCS) and mental (MCS) composite scale scores. Independent sample t-tests were calculated to compare differences in HRQOL between settings. Multivariate regression models then examined the effect of treatment setting on HRQOL, adjusting for covariate demographic factors, mood symptoms (Internal State Scale), hazardous drinking (AUDIT-C), and substance abuse. RESULTS A total of 384 enrolled participants completed baseline surveys. MCS and PCS scores reflected similar impairment in HRQOL across PC and CMH settings (p=0.98 and p=0.49, respectively). Depressive symptoms were associated with lower MCS scores (B=-0.68, p<0.001) while arthritis/chronic pain was strongly related to lower PCS scores (B=-5.23, p<0.001). LIMITATIONS This study lacked a formal diagnostic interview, relied on cross-sectional self-report, and sampled from a small number of sites in two states. DISCUSSION Participants reported similar impairments in both mental and physical HRQOL in PC and CMH treatment settings, emphasizing the need for integrated care for patients with bipolar disorder regardless of where they present for treatment.
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Abraham KM, Stein CH. When Mom has a Mental Illness: Role Reversal and Psychosocial Adjustment Among Emerging Adults. J Clin Psychol 2013; 69:600-15. [DOI: 10.1002/jclp.21950] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abraham KM, Stein CH. Emerging adults' perspectives on their relationships with mothers with mental illness: implications for caregiving. THE AMERICAN JOURNAL OF ORTHOPSYCHIATRY 2012; 82:542-9. [PMID: 23039352 DOI: 10.1111/j.1939-0025.2012.01175.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Guided by a life course perspective, the current study examined whether emerging adults with and without mothers with affective disorders viewed their relationships with their mothers differently, and whether aspects of the emerging adult-mother relationship were associated with reports of caregiving for mothers. Reports from emerging adults with mothers with affective disorders (n = 46) were compared to reports from emerging adults with mothers without mental illness (n = 64). Results indicated that emerging adults with mothers with affective disorders reported significantly lower levels of affection, felt obligation, reciprocity, and future caregiving intentions, and significantly higher levels of role reversal in their relationships with their mothers. Reported current caregiving levels did not differ between emerging adults with and without mothers with affective disorders. Hierarchical multiple regression analyses generally indicated higher levels of felt obligation were associated with higher levels of caregiving, regardless of maternal mental health status. Results and future research directions are discussed from a life course perspective.
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Cohen JL, Abraham KM, Burk JP, Stein CH. Emerging opportunities for psychologists: Joining consumers in the recovery-oriented care movement. ACTA ACUST UNITED AC 2012. [DOI: 10.1037/a0024394] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Stein CH, Abraham KM, Bonar EE, Leith JE, Kraus SW, Hamill AC, Gumber S, Hoffmann E, Fogo WR. Family ties in tough times: how young adults and their parents view the U.S. economic crisis. JOURNAL OF FAMILY PSYCHOLOGY : JFP : JOURNAL OF THE DIVISION OF FAMILY PSYCHOLOGY OF THE AMERICAN PSYCHOLOGICAL ASSOCIATION (DIVISION 43) 2011; 25:449-454. [PMID: 21534669 DOI: 10.1037/a0023697] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The present intergenerational study examined the perceived impact of the recent U.S. economic crisis on a sample of 68 young adult-parent dyads. The relative contribution of perceived economic pressure, reports of adult child-parent relationship quality, and concerns about the economic future in accounting for variation in self-reports of psychological distress for adult children and their middle-aged parents were examined. Parents' concerns about their children's economic future accounted for variation in their reports of anxiety and depressed mood above and beyond that of perceived economic pressures and their views of the parent-child relationship. In contrast, for young adults, reports of personal economic pressure were generally related to self-reported anxiety and depressed mood. Implications of findings for research and practice are discussed.
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Abraham KM, Stein CH. Staying connected: young adults' felt obligation toward parents with and without mental illness. JOURNAL OF FAMILY PSYCHOLOGY : JFP : JOURNAL OF THE DIVISION OF FAMILY PSYCHOLOGY OF THE AMERICAN PSYCHOLOGICAL ASSOCIATION (DIVISION 43) 2010; 24:125-134. [PMID: 20438188 DOI: 10.1037/a0018973] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The present study compares 94 young adults' self-reported felt obligation toward parents, psychological symptoms, psychological well-being, and interpersonal loneliness in three family types: families where a mother has serious mental illness, families where a father has serious mental illness, and families with nondistressed parents. Results indicated no significant differences in felt obligation toward mothers or fathers as a function of family type. Young adults with a mother with serious mental illness reported significantly more psychological adjustment difficulties than their peers with a father with serious mental illness or nondistressed parents. Young adults' reports of felt obligation toward both parents were significantly positively correlated with young adults' psychological adjustment in families with a parent with serious mental illness, but were not significantly correlated in families with nondistressed parents. Study limitations, future directions for research, and implications for clinical practice are discussed.
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Stein CH, Abraham KM, Bonar EE, McAuliffe CE, Fogo WR, Faigin DA, Raiya HA, Potokar DN. Making Meaning from Personal Loss: Religious, Benefit Finding, and Goal-oriented Attributions. JOURNAL OF LOSS & TRAUMA 2009. [DOI: 10.1080/15325020802173819] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Christopher AN, Victoria Kuo S, Abraham KM, Noel LW, Linz HE. Materialism and affective well-being: the role of social support. PERSONALITY AND INDIVIDUAL DIFFERENCES 2004. [DOI: 10.1016/j.paid.2003.09.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Longo NS, Wang X, Wildin RS, Abraham KM. Regulation of Src-family protein tyrosine kinase transcription during lymphocyte ontogeny. Mol Immunol 1999; 36:979-92. [PMID: 10698302 DOI: 10.1016/s0161-5890(99)00134-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The distribution and quantity of cellular signaling elements influence response patterns to a variety of stimuli. As protein tyrosine phosphorylation is a requisite event induced by a majority of surface receptors, and protein tyrosine kinases of the src-family (src-PTKs) act as proximal transducers for many hematopoietic receptors, we have designed a quantitative RT-PCR assay to measure src-family PTK expression during critical stages of lymphocyte ontogeny. With this assay we demonstrate that the distal promoter element regulating expression of lck, a src-PTK essential for T-cell development and activation, is similarly regulated during ontogeny of T and B cells. However, lck transcript abundance is drastically reduced in B lineage cells, suggesting that transcriptional elements influencing lck promoter activity are modulated in these cells. Moreover, although transcripts encoding the src-PTK fyn accumulate at 0.1% of lck mRNA levels in thymocytes, diminished activity of the lck distal promoter in the B-cell background brings lck and fyn transcript levels to near equivalence in this population. Importantly, transcripts arising from the lck distal promoter element and the fyn locus are similarly upregulated during developmental transitions associated with antigen-receptor expression in both B and T cells. These findings suggest that although the magnitude of lck and fyn expression is differentially regulated in B and T cells, expression at these loci is similarly developmentally programmed during ontogeny of both lymphocyte lineages.
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Abraham KM, Longo NS, Hewitt JA. Detection of transgene integrants and homologous recombinants in mice by polymerase chain reaction. Methods Mol Biol 1998; 92:245-50. [PMID: 9664520 DOI: 10.1385/0-89603-497-6:245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Lin K, Abraham KM. Targets of p56(lck) activity in immature thymoblasts: stimulation of the Ras/Raf/MAPK pathway. Int Immunol 1997; 9:291-306. [PMID: 9040011 DOI: 10.1093/intimm/9.2.291] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Previous studies suggest that p56(lck) activity influences thymocyte development at a stage prior to TCR alphabeta expression. Transgenic mice that express high levels of p56(lck) activity during thymopoiesis develop thymic lymphomas consisting of cells with immature surface phenotypes. We have utilized cell lines derived from lck-induced thymic tumors to define biochemical pathways regulated by p56(lck) activity in immature thymocytes. Here we report that components of the Ras/Raf/MAPK pathway are constitutively activated in these lck-transformed immature thymoblasts. p56(lck) utilizes Shc and Grb2 adaptors to mediate activation of p21(ras) in the thymoblast lines by promoting tyrosine phosphorylation of the Shc protein and constitutive interaction between Shc and Grb2. The putative guanine nucleotide exchange factor p95(vav) is also maintained in constitutively tyrosine phosphorylated form as a result of elevated Lck activity. One target of activated Ras, the Raf-1 kinase, is hyperphosphorylated and downstream targets of activated Raf-1, Erk1 and Erk2, are hyperphosphorylated and activated in Lck-transformed thymocytes. Forskolin treatment reverses Raf-1 hyperphosphorylation in the cells and inhibits proliferation by blocking G1/S transition. In contrast, conventional protein tyrosine kinase inhibitors block proliferation by arresting Lck thymoblasts at G2/M. Lck-mediated stimulation of the Ras/Raf/MAPK pathway is also required to maintain cell viability by preventing programmed cell death. In summary, p56(lck) activity stimulates G1/S transition in immature thymoblasts and maintains cell viability via transduction of constitutive activation signals downstream to components of the Ras/Raf/MAPK pathway.
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Nakayama T, Wiest DL, Abraham KM, Munitz TI, Perlmutter RM, Singer A. Decreased signaling competence as a result of receptor overexpression: overexpression of CD4 reduces its ability to activate p56lck tyrosine kinase and to regulate T-cell antigen receptor expression in immature CD4+CD8+ thymocytes. Proc Natl Acad Sci U S A 1993; 90:10534-8. [PMID: 7902564 PMCID: PMC47811 DOI: 10.1073/pnas.90.22.10534] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Thymic selection of the developing T-cell repertoire occurs in immature CD4+CD8+ thymocytes, with the fate of individual thymocytes determined by the specificity of T-cell antigen receptor they express. However, T-cell antigen receptor expression in immature CD4+CD8+ thymocytes is actively down-regulated in CD4+CD8+ thymocytes by CD4-mediated tyrosine kinase signals that are generated in the thymus as a result of CD4 engagement by intrathymic ligands. In the present study we have examined the effect of CD4 overexpression in CD4+CD8+ thymocytes on activation of CD4-associated p56lck tyrosine kinase and regulation of T-cell antigen receptor expression. Augmented CD4 expression in CD4+CD8+ thymocytes did not result in commensurate increases in associated p56lck molecules, so that CD4 expression was quantitatively disproportionate to that of its associated signaling molecule p56lck. Interestingly, we found that CD4 overexpression significantly interfered with the ability of CD4 crosslinking to activate associated p56lck molecules and significantly interfered with the ability of CD4 to regulate T-cell antigen receptor expression. Thus, this study provides an example in which receptor overexpression leads to decreased receptor signaling competence.
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Levin SD, Abraham KM, Anderson SJ, Forbush KA, Perlmutter RM. The protein tyrosine kinase p56lck regulates thymocyte development independently of its interaction with CD4 and CD8 coreceptors [corrected]. J Exp Med 1993; 178:245-55. [PMID: 8391060 PMCID: PMC2191071 DOI: 10.1084/jem.178.1.245] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The lck gene encodes a lymphocyte-specific protein tyrosine kinase of the nonreceptor type that is implicated in signal transduction pathways emanating from the CD4 and CD8 coreceptors. Previous studies also support a role for p56lck in regulating T cell receptor beta gene rearrangements and, more generally, thymocyte development. Here we report that a mutant form of p56lck, which is incapable of interacting with CD4 or CD8, behaves indistinguishably from association-competent p56lck with respect to its ability to affect thymocyte maturation. The effects of p56lck remained specific in that the closely related src-family kinase p59hck was incapable of substituting for p56lck in arresting beta locus gene rearrangements. These data support the view that src-family kinases perform highly specialized and often nonoverlapping functions in hematopoietic cells, and that p56lck acts independently of its association with CD4 and CD8 to regulate thymocyte development.
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Anderson SJ, Abraham KM, Nakayama T, Singer A, Perlmutter RM. Inhibition of T-cell receptor beta-chain gene rearrangement by overexpression of the non-receptor protein tyrosine kinase p56lck. EMBO J 1992; 11:4877-86. [PMID: 1334460 PMCID: PMC556965 DOI: 10.1002/j.1460-2075.1992.tb05594.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The variable region genes of the T cell receptor (TCR) alpha and beta chains are assembled by somatic recombination of separate germline elements. During thymocyte development, gene rearrangements display both an ordered progression, with beta chain formation preceding alpha chain, and allelic exclusion, with each cell containing a single functional beta chain rearrangement. Although considerable evidence supports the view that the individual loci are regulated independently, signaling molecules that may participate in controlling TCR gene recombination remain unidentified. Here we report that the lymphocyte-specific protein tyrosine kinase p56lck, when overexpressed in developing thymocytes, provokes a reduction in V beta--D beta rearrangement while permitting normal juxtaposition of other TCR gene segments. Our data support a model in which p56lck activity impinges upon a signaling process that ordinarily permits allelic exclusion at the beta-chain locus.
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Abraham KM, Levin SD, Marth JD, Forbush KA, Perlmutter RM. Delayed thymocyte development induced by augmented expression of p56lck. J Exp Med 1991; 173:1421-32. [PMID: 1709675 PMCID: PMC2190838 DOI: 10.1084/jem.173.6.1421] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Accumulating evidence supports the contention that CD4 and CD8 receptor molecules play a critical signaling role during thymocyte development. The lymphocyte-specific protein tyrosine kinase (p56lck), by virtue of its physical association with these surface components, provides a likely candidate for the biochemical signal transducing element required for these effects. To investigate the function of p56lck in T lymphocytes, transgenic mice were produced that carry either the wild-type lck gene or a mutated lck gene encoding a constitutively activated form of p56lck (p56lckF505). Both transgenes were expressed in thymocytes under the control of the lck proximal promoter element. A large set of founder animals was obtained in which steady-state accumulation of lck transgene mRNA directly correlated with transgene copy number, suggesting that this transgene contains a dominant control region. Progeny of these founders exhibited a transgene-dependent dose-related decrease in the production of thymocytes bearing functional antigen receptors. This effect was strictly dependent on p56lck activity, in that both wild-type and mutated versions of the genes induced similar effects with differing efficiencies. Remarkably, even a twofold increase in p56lck abundance was sufficient to substantially disrupt the appearance of functional thymocytes. These results indicate that thymocyte maturation is regulated in part by signals derived from p56lck.
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Abraham KM, Levin SD, Marth JD, Forbush KA, Perlmutter RM. Thymic tumorigenesis induced by overexpression of p56lck. Proc Natl Acad Sci U S A 1991; 88:3977-81. [PMID: 1708890 PMCID: PMC51576 DOI: 10.1073/pnas.88.9.3977] [Citation(s) in RCA: 138] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The lck gene encodes a membrane-associated protein tyrosine kinase (p56lck) that is believed to participate in lymphocyte-specific signal transduction pathways. To investigate the function of this molecule, transgenic mice were generated carrying the wild-type lck gene or a mutated lck gene encoding a constitutively activated form of p56lck (p56lckF505). Transgene expression in thymocytes was achieved in each case using the lck proximal promoter element. Mice expressing high levels of either p56lckF505 or p56lckY505 reproducibly developed thymic tumors. The sensitivity of thymocytes to p56lck-induced transformation suggests that disturbances in lck expression may contribute to the pathogenesis of some human neoplastic diseases.
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Cooke MP, Abraham KM, Forbush KA, Perlmutter RM. Regulation of T cell receptor signaling by a src family protein-tyrosine kinase (p59fyn). Cell 1991; 65:281-91. [PMID: 2015626 DOI: 10.1016/0092-8674(91)90162-r] [Citation(s) in RCA: 325] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Engagement of the clonotypic antigen receptor (TCR) on T lymphocytes provokes an activation response leading to cell proliferation and lymphokine secretion. To examine the molecular basis of T cell signaling, we generated transgenic animals in which a lymphocyte-specific nonreceptor protein-tyrosine kinase p59fyn(T) is 20-fold overexpressed in developing T lineage cells. Thymocytes from these mice, analyzed using both cellular and biochemical assays, were remarkably hyperstimulable. Moreover, the responsiveness of normal thymocytes to TCR-derived signals correlated well with the extent to which p59fyn was expressed in these cells. Overexpression of a catalytically inactive form of p59fyn substantially inhibited TCR-mediated activation in otherwise normal thymocytes. These effects are unique to p59fyn; overexpression of a closely related T cell-specific tyrosine kinase, p56lck, elicits dramatically different phenotypes. Our results suggest that p59fyn is a critically important component of the TCR signal transduction apparatus.
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Wildin RS, Garvin AM, Pawar S, Lewis DB, Abraham KM, Forbush KA, Ziegler SF, Allen JM, Perlmutter RM. Developmental regulation of lck gene expression in T lymphocytes. J Exp Med 1991; 173:383-93. [PMID: 1988541 PMCID: PMC2118802 DOI: 10.1084/jem.173.2.383] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In the mouse and human, mRNA transcripts encoding the lymphocyte-specific protein tyrosine kinase p56lck are derived from two separate promoters resulting in heterogeneity in the 5' untranslated region sequence. The proximal promoter lies just 5' to the coding region for the gene and is active only in thymocytes. In contrast, the distal promoter lies 34 kilobases (kb) 5' in the human, and is active both in thymocytes and mature peripheral T cells. As previously reported, transgenic mice bearing functional proximal promoter sequence juxtaposed with the SV40 large T antigen gene invariably develop lymphoid tumors confined to the thymus. In the current work, transgenic mice bearing a 2.6-kb fragment of the human distal promoter fused to the SV40 large T antigen gene express large T antigen in thymocytes and in peripheral lymphoid cells, and develop tumors of both the thymus and the peripheral lymphoid organs. The ability of the human distal promoter to function appropriately in transgenic mice is consistent with the strong similarity observed between the mouse and human distal promoter sequences. With the exception of a single short interval that serves as a target for binding of nuclear factors, significant sequence similarity is not seen when the distal and proximal promoter sequences are compared. Hence, developmentally regulated, lineage-specific transcription of the lck gene is mediated by distinct promoter sequences that appear to be capable of functioning independently.
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Desai BB, Abraham KM, Teale JM. The isotype potential of B cells present in BALB/c mice chronically infected with Mesocestoides corti. Cell Immunol 1990; 130:139-49. [PMID: 1975771 DOI: 10.1016/0008-8749(90)90168-q] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Infection of BALB/c mice with Mesocestoides corti results in a chronic infection with a pronounced splenomegaly and hypergammaglobulinemia. A prominent feature of this infection is that the vast majority of serum immunoglobulin produced is restricted to IgG1 and IgM. As much as 30-fold increases in serum IgG1 levels have been noted. To ascertain whether, as a result of infection, the resident B cell pool is committed to IgG1, B cells from infected animals were tested for their ability to produce various isotypes after stimulation. In one series of experiments, B cells from normal and infected animals were used as donor cells in the splenic fragment assay. The results show that the frequency of 2,4-dinitrophenyl-specific and phosphorylcholine-specific B cells remains unaltered in infected animals compared to controls. Importantly, the hapten-specific B cell clones induced were found to express multiple isotypes. These results demonstrate that the nonactivated B cell pool in spleens of infected mice is not committed to IgG1 and IgM production.
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