40 results on '"Pilkinton M"'
Search Results
2. Comparison of the strength of mesh attachment using barbed and non-barbed sutures: 8
- Author
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Pilkinton, M., Levine, G., Bennett, L., Winkler, H., and Finamore, P.
- Published
- 2017
- Full Text
- View/download PDF
3. ARF-induced downregulation of Mip130/LIN-9 protein levels mediates a positive feedback that leads to increased expression of p16Ink4a and p19Arf
- Author
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Song, J, Sandoval, R, Pilkinton, M A, Tian, X, Raychaudhuri, P, and Colamonici, O R
- Published
- 2010
- Full Text
- View/download PDF
4. Mammalian Mip/LIN-9 interacts with either the p107, p130/E2F4 repressor complex or B-Myb in a cell cycle-phase-dependent context distinct from the Drosophila dREAM complex
- Author
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Pilkinton, M, Sandoval, R, and Colamonici, O R
- Published
- 2007
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5. Deep sequence analysis of HIV adaptation following vertical transmission reveals the impact of immune pressure on the evolution of HIV
- Author
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Currenti, J., Chopra, A., John, M., Leary, S., McKinnon, E., Alves, E., Pilkinton, M., Smith, R., Barnett, L., McDonnell, W.J., Lucas, M., Noel, F., Mallal, S., Conrad, J.A., Kalams, S.A., Gaudieri, S., Currenti, J., Chopra, A., John, M., Leary, S., McKinnon, E., Alves, E., Pilkinton, M., Smith, R., Barnett, L., McDonnell, W.J., Lucas, M., Noel, F., Mallal, S., Conrad, J.A., Kalams, S.A., and Gaudieri, S.
- Abstract
Human immunodeficiency virus (HIV) can adapt to an individual’s T cell immune response via genomic mutations that affect antigen recognition and impact disease outcome. These viral adaptations are specific to the host’s human leucocyte antigen (HLA) alleles, as these molecules determine which peptides are presented to T cells. As HLA molecules are highly polymorphic at the population level, horizontal transmission events are most commonly between HLA-mismatched donor/recipient pairs, representing new immune selection environments for the transmitted virus. In this study, we utilised a deep sequencing approach to determine the HIV quasispecies in 26 mother-to-child transmission pairs where the potential for founder viruses to be pre-adapted is high due to the pairs being haplo-identical at HLA loci. This scenario allowed the assessment of specific HIV adaptations following transmission in either a non-selective immune environment, due to recipient HLA mismatched to original selecting HLA, or a selective immune environment, mediated by matched donor/recipient HLA. We show that the pattern of reversion or fixation of HIV adaptations following transmission provides insight into the replicative cost, and likely compensatory networks, associated with specific adaptations in vivo. Furthermore, although transmitted viruses were commonly heavily pre-adapted to the child’s HLA genotype, we found evidence of de novo post-transmission adaptation, representing new epitopes targeted by the child’s T cell response. High-resolution analysis of HIV adaptation is relevant when considering vaccine and cure strategies for individuals exposed to adapted viruses via transmission or reactivated from reservoirs.
- Published
- 2019
6. 09: Return to baseline functional status in older women undergoing pelvic organ prolapse surgery
- Author
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Lee, D., primary, Wasson, M., additional, Hallock, J.L., additional, Heredia-Melero, G., additional, Kinman, C.L., additional, Maldonado, P.A., additional, Pilkinton, M., additional, Greer, J.A., additional, and Arya, L.A., additional
- Published
- 2019
- Full Text
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7. Population dynamics of tumor-specific CD8 T cell differentiation from plastic to fixed dysfunctional states
- Author
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Philip, M., Pilkinton, M., Ramesh, R., McDonnell, W.J., Gangula, R.D., Camara, S., Chopra, A., Schietinger, A., Mallal, S.A., Philip, M., Pilkinton, M., Ramesh, R., McDonnell, W.J., Gangula, R.D., Camara, S., Chopra, A., Schietinger, A., and Mallal, S.A.
- Abstract
Tumor-specific CD8 T cells (TST) encountering cognate antigen in tumors differentiate to a dysfunctional state characterized by expression of multiple inhibitory receptors and failure to make effector cytokines. We demonstrated that TST differentiate through two discrete chromatin states; TST were initially in a plastic chromatin state and could be functionally rescued but then transitioned to a fixed chromatin state resistant to therapeutic reprogramming. T cells harboring these discrete chromatin states could be identified with distinct, novel membrane protein expression profiles, permitting prospective identification of reprogrammable tumor-specific T cells from bulk tumor-infiltrating T cell populations. Importantly, human tumor-infiltrating PD1-high CD8 T cells were in a similar chromatin accessibility state as murine fixed dysfunctional T cells. Based on our studies, two models could describe TST differentiation: (i) TST progress en-masse from the plastic to fixed state, potentially through a transitional state or (ii) individual TST within a population exist in either the plastic or fixed dysfunctional state; initially, most TST are in the plastic state, however over time plastic T cells fail to proliferate or die while the fixed dysfunctional TST preferentially proliferate and/or survive. To test these models, we carried out single-cell RNA-Sequencing on TST at various time points during tumor progression. Determining the population dynamics of TST differentiation through dysfunctional states in tumors could inform our strategies for TST rescue, for example, by selecting rare plastic TST from bulk populations versus novel strategies to reprogram the epigenome of fixed dysfunctional TST.
- Published
- 2018
8. Evidence of CD4+ T cell-mediated immune pressure on the Hepatitis C virus genome
- Author
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Lucas, M., Deshpande, P., James, I., Rauch, A., Pfafferott, K., Gaylard, E., Merani, S., Plauzolles, A., Lucas, A., McDonnell, W., Kalams, S., Pilkinton, M., Chastain, C., Barnett, L., Prosser, A., Mallal, S., Fitzmaurice, K., Drummer, H., Ansari, M.A., Pedergnana, V., Barnes, E., John, M., Kelleher, D., Klenerman, P., Gaudieri, S., Lucas, M., Deshpande, P., James, I., Rauch, A., Pfafferott, K., Gaylard, E., Merani, S., Plauzolles, A., Lucas, A., McDonnell, W., Kalams, S., Pilkinton, M., Chastain, C., Barnett, L., Prosser, A., Mallal, S., Fitzmaurice, K., Drummer, H., Ansari, M.A., Pedergnana, V., Barnes, E., John, M., Kelleher, D., Klenerman, P., and Gaudieri, S.
- Abstract
Hepatitis C virus (HCV)-specific T cell responses are critical for immune control of infection. Viral adaptation to these responses, via mutations within regions of the virus targeted by CD8+ T cells, is associated with viral persistence. However, identifying viral adaptation to HCV-specific CD4+ T cell responses has been difficult although key to understanding anti-HCV immunity. In this context, HCV sequence and host genotype from a single source HCV genotype 1B cohort (n = 63) were analyzed to identify viral changes associated with specific human leucocyte antigen (HLA) class II alleles, as these variable host molecules determine the set of viral peptides presented to CD4+ T cells. Eight sites across the HCV genome were associated with HLA class II alleles implicated in infection outcome in this cohort (p ≤ 0.01; Fisher’s exact test). We extended this analysis to chronic HCV infection (n = 351) for the common genotypes 1A and 3A. Variation at 38 sites across the HCV genome were associated with specific HLA class II alleles with no overlap between genotypes, suggestive of genotype-specific T cell targets, which has important implications for vaccine design. Here we show evidence of HCV adaptation to HLA class II-restricted CD4+ T cell pressure across the HCV genome in chronic HCV infection without a priori knowledge of CD4+ T cell epitopes.
- Published
- 2018
9. Evidence of CD4(+) T cell-mediated immune pressure on the Hepatitis C virus genome
- Author
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Lucas, M, Deshpande, P, James, I, Rauch, A, Pfafferott, K, Gaylard, E, Merani, S, Plauzolles, A, Lucas, A, McDonnell, W, Kalams, S, Pilkinton, M, Chastain, C, Barnett, L, Prosser, A, Mallal, S, Fitzmaurice, K, Drummer, H, Ansari, MA, Pedergnana, V, Barnes, E, John, M, Kelleher, D, Klenerman, P, Gaudieri, S, Lucas, M, Deshpande, P, James, I, Rauch, A, Pfafferott, K, Gaylard, E, Merani, S, Plauzolles, A, Lucas, A, McDonnell, W, Kalams, S, Pilkinton, M, Chastain, C, Barnett, L, Prosser, A, Mallal, S, Fitzmaurice, K, Drummer, H, Ansari, MA, Pedergnana, V, Barnes, E, John, M, Kelleher, D, Klenerman, P, and Gaudieri, S
- Abstract
Hepatitis C virus (HCV)-specific T cell responses are critical for immune control of infection. Viral adaptation to these responses, via mutations within regions of the virus targeted by CD8+ T cells, is associated with viral persistence. However, identifying viral adaptation to HCV-specific CD4+ T cell responses has been difficult although key to understanding anti-HCV immunity. In this context, HCV sequence and host genotype from a single source HCV genotype 1B cohort (n = 63) were analyzed to identify viral changes associated with specific human leucocyte antigen (HLA) class II alleles, as these variable host molecules determine the set of viral peptides presented to CD4+ T cells. Eight sites across the HCV genome were associated with HLA class II alleles implicated in infection outcome in this cohort (p ≤ 0.01; Fisher's exact test). We extended this analysis to chronic HCV infection (n = 351) for the common genotypes 1A and 3A. Variation at 38 sites across the HCV genome were associated with specific HLA class II alleles with no overlap between genotypes, suggestive of genotype-specific T cell targets, which has important implications for vaccine design. Here we show evidence of HCV adaptation to HLA class II-restricted CD4+ T cell pressure across the HCV genome in chronic HCV infection without a priori knowledge of CD4+ T cell epitopes.
- Published
- 2018
10. 04: Patient knowledge and preferences regarding hysterectomy route: A study from the Fellows' Pelvic Research Network
- Author
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Jacobs, K.M., primary, Hokenstad, E.D., additional, Hamner, J.J., additional, Park, B., additional, Mahal, A., additional, Shannon, M., additional, Zigman, J., additional, Pilkinton, M., additional, Sheyn, D., additional, Elmer, C., additional, Korbly, N., additional, and Sung, V., additional
- Published
- 2018
- Full Text
- View/download PDF
11. Adipose tissue is enriched for activated and Late-differentiated CD8+ T cells, and shows distinct CD8+ receptor usage, compared to blood in HIV-infected persons
- Author
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Koethe, J.R., McDonnell, W., Kennedy, A., Abana, C.O., Pilkinton, M., Setliff, I., Georgiev, I., Barnett, L., Hager, C.C., Smith, R., Kalams, S.A., Hasty, A., Mallal, S., Koethe, J.R., McDonnell, W., Kennedy, A., Abana, C.O., Pilkinton, M., Setliff, I., Georgiev, I., Barnett, L., Hager, C.C., Smith, R., Kalams, S.A., Hasty, A., and Mallal, S.
- Abstract
BACKGROUND: Adverse viral and medication effects on adipose tissue contribute to the development of metabolic disease in HIV-infected persons, but T cells also have a central role modulating local inflammation and adipocyte function. We sought to characterize potentially proinflammatory T-cell populations in adipose tissue among persons on long-term antiretroviral therapy and assess whether adipose tissue CD8 T cells represent an expanded, oligoclonal population. METHODS: We recruited 10 HIV-infected, non-diabetic, overweight or obese adults on efavirenz, tenofovir, and emtricitabine for >4 years with consistent viral suppression. We collected fasting blood and subcutaneous abdominal adipose tissue to measure the percentage of CD4 and CD8 T cells expressing activation, exhaustion, late differentiation/senescence, and memory surface markers. We performed T-cell receptor (TCR) sequencing on sorted CD8 cells. We compared the proportion of each T-cell subset and the TCR repertoire diversity, in blood versus adipose tissue. RESULTS: Adipose tissue had a higher percentage of CD3CD8 T cells compared with blood (61.0% vs. 51.7%, P < 0.01) and was enriched for both activated CD8HLA-DR T cells (5.5% vs. 0.9%, P < 0.01) and late-differentiated CD8CD57 T cells (37.4% vs. 22.7%, P < 0.01). Adipose tissue CD8 T cells displayed distinct TCRβ V and J gene usage, and the Shannon Entropy index, a measure of overall TCRβ repertoire diversity, was lower compared with blood (4.39 vs. 4.46; P = 0.05). CONCLUSIONS: Adipose tissue is enriched for activated and late-differentiated CD8 T cells with distinct TCR usage. These cells may contribute to tissue inflammation and impaired adipocyte fitness in HIV-infected persons.
- Published
- 2017
12. 19: Randomized controlled trial of two voiding trials after midurethral sling with or without colporrhaphy
- Author
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Williams, K.S., primary, Pilkinton, M., additional, Firoozi, F., additional, Shalom, D., additional, and Winkler, H., additional
- Published
- 2017
- Full Text
- View/download PDF
13. 8: Comparison of the strength of mesh attachment using barbed and non-barbed sutures
- Author
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Pilkinton, M., primary, Levine, G., additional, Bennett, L., additional, Winkler, H., additional, and Finamore, P., additional
- Published
- 2017
- Full Text
- View/download PDF
14. Association Between Lower Urinary Tract Symptoms and Endometriosis Before and After Laparoscopy
- Author
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Pilkinton, M, primary, Cohen, L, additional, and Hardart, A, additional
- Published
- 2015
- Full Text
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15. The Use of Inflammatory Cytokine Levels as a Measure of Symptom Distress and Quality of Life in Patients With Overactive Bladder
- Author
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Pilkinton, M, primary, Wolff, B, additional, Pillalamarri, N, additional, Winkler, H, additional, and Shalom, D, additional
- Published
- 2015
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16. Patient Characteristics and the Incidence of Postoperative Venous Thromboembolism in Laparoscopy and Laparotomy
- Author
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Datta, M.S., primary, Bump, C., additional, Peak, G., additional, Pilkinton, M., additional, Roy, P., additional, Moshier, E.L., additional, and Nezhat, F.R., additional
- Published
- 2012
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17. TANF Recipients' Barriers to Employability: Substance Abuse and Domestic Violence.
- Author
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Pilkinton M
- Subjects
- *
PUBLIC welfare laws , *SUBSTANCE abuse treatment , *EMPLOYMENT , *DOMESTIC violence , *MEDICAL needs assessment , *MEDICAL referrals , *PARENTING , *PUBLIC welfare , *SUBSTANCE abuse , *GOVERNMENT policy , *TREATMENT programs - Abstract
Recipients of temporary assistance for needy families (TANF) encounter a variety of expectations and sanctions. Recipients face work requirements, limited resources, and barriers to employability, including the barrier of substance use. This article addresses the sanctions that are applied to clients who do not meet expectations of the policy, barriers to employability, disparities in resources, and factors influencing referrals for substance abuse treatment for TANF clients. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
18. ARF-induced downregulation of Mip130/LIN-9 protein levels mediates a positive feedback that leads to increased expression of p16Ink4a and p19Arf.
- Author
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Song, J., Sandoval, R., Pilkinton, M. A., Tian, X., Raychaudhuri, P., and Colamonici, O. R.
- Subjects
ONCOGENES ,CELLULAR aging ,CELL cycle ,LABORATORY mice ,FIBROBLAST growth factors ,ANIMAL models of carcinogenesis - Abstract
The ARF-MDM2-p53 pathway constitutes one of the most important mechanisms of surveillance against oncogenic transformation, and its inactivation occurs in a large proportion of cancers. Here, we show that ARF regulates Mip130/LIN-9 by inducing its translocation to the nucleolus and decreasing the expression of the Mip130/LIN-9 protein through a post-transcriptional mechanism. The knockdown of Mip130/LIN-9 in p53
−/− and Arf−/− mouse embryonic fibroblasts (MEFs) mimics some effects of ARF, such as the downregulation of B-Myb, impaired induction of G2/M genes, and a decrease in cell proliferation. Importantly, although the knockdown of Mip130/LIN-9 reduced the proliferation of p53 or Arf-null MEFs, only p53−/− MEFs showed a senescence-like state and an increase in the expression of Arf and p16. Interestingly, the increase in p16 and ARF is indirect because the Mip130/LIN-9 knockdown decreased the transcription of negative regulators of the Ink4a/Arf locus, such as BUBR1 and CDC6. Chromatin immunoprecipitation assays also reveal that Mip130/LIN-9 occupies the promoters of the BubR1 and cdc6 genes, suggesting that Mip130/LIN-9 is necessary for the expression of these genes. Altogether, these results indicate that there is a feedback mechanism between ARF and Mip130/LIN-9 in which either the increase of ARF or the decrease in Mip130/LIN-9 causes a further increase in the expression of Arf and p16. [ABSTRACT FROM AUTHOR]- Published
- 2010
- Full Text
- View/download PDF
19. High frequency of shared clonotypes in human T cell receptor repertoires
- Author
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Soto, C, primary, Bombardi, RG, additional, Kozhevnikov, M, additional, Sinkovits, RS, additional, Chen, EC, additional, Branchizio, A, additional, Kose, N, additional, Day, SB, additional, Pilkinton, M, additional, Gujral, M, additional, Mallal, S, additional, and Crowe, JE, additional
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- View/download PDF
20. ARF-induced downregulation of Mip130/LIN-9 protein levels mediates a positive feedback that leads to increased expression of p16Ink4a and p19Arf.
- Author
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Song, J., Sandoval, R., Pilkinton, M. A., Tian, X., Raychaudhuri, P., and Colamonici, O. R.
- Subjects
- *
ONCOGENES , *CELLULAR aging , *CELL cycle , *LABORATORY mice , *FIBROBLAST growth factors , *ANIMAL models of carcinogenesis - Abstract
The ARF-MDM2-p53 pathway constitutes one of the most important mechanisms of surveillance against oncogenic transformation, and its inactivation occurs in a large proportion of cancers. Here, we show that ARF regulates Mip130/LIN-9 by inducing its translocation to the nucleolus and decreasing the expression of the Mip130/LIN-9 protein through a post-transcriptional mechanism. The knockdown of Mip130/LIN-9 in p53−/− and Arf−/− mouse embryonic fibroblasts (MEFs) mimics some effects of ARF, such as the downregulation of B-Myb, impaired induction of G2/M genes, and a decrease in cell proliferation. Importantly, although the knockdown of Mip130/LIN-9 reduced the proliferation of p53 or Arf-null MEFs, only p53−/− MEFs showed a senescence-like state and an increase in the expression of Arf and p16. Interestingly, the increase in p16 and ARF is indirect because the Mip130/LIN-9 knockdown decreased the transcription of negative regulators of the Ink4a/Arf locus, such as BUBR1 and CDC6. Chromatin immunoprecipitation assays also reveal that Mip130/LIN-9 occupies the promoters of the BubR1 and cdc6 genes, suggesting that Mip130/LIN-9 is necessary for the expression of these genes. Altogether, these results indicate that there is a feedback mechanism between ARF and Mip130/LIN-9 in which either the increase of ARF or the decrease in Mip130/LIN-9 causes a further increase in the expression of Arf and p16. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
21. To tell the truth freely: the life of Ida B. Wells.
- Author
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Pilkinton, M. W.
- Subjects
NONFICTION - Published
- 2014
22. Moisture of the earth: Mary Robinson, civil rights and textile union activist: an oral history.
- Author
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Pilkinton, M. W.
- Subjects
AFRICAN American women ,NONFICTION - Abstract
The article reviews the book "Moisture of the earth: Mary Robinson, civil rights and textile union activist: an oral history," by Mary Robinson, edited by Fran Leeper.
- Published
- 2010
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- View/download PDF
23. To tell the truth freely: the life of Ida B. Wells.
- Author
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Pilkinton, M. W.
- Subjects
NONFICTION - Abstract
The article reviews the book "To Tell the Truth Freely: The Life of Ida B. Wells," by Mia Bay.
- Published
- 2009
- Full Text
- View/download PDF
24. Predictors of HIV rebound differ by timing of antiretroviral therapy initiation.
- Author
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Li JZ, Melberg M, Kittilson A, Abdel-Mohsen M, Li Y, Aga E, Bosch RJ, Wonderlich ER, Kinslow J, Giron LB, Di Germanio C, Pilkinton M, MacLaren L, Keefer M, Fox L, Barr L, Acosta E, Ananworanich J, Coombs R, Mellors J, Deeks S, Gandhi RT, Busch M, Landay A, Macatangay B, and Smith DM
- Subjects
- Humans, Proviruses genetics, CD8-Positive T-Lymphocytes, Viral Load, DNA, HIV Infections
- Abstract
BACKGROUNDIdentifying factors that predict the timing of HIV rebound after treatment interruption will be crucial for designing and evaluating interventions for HIV remission.METHODSWe performed a broad evaluation of viral and immune factors that predict viral rebound (AIDS Clinical Trials Group A5345). Participants initiated antiretroviral therapy (ART) during chronic (N = 33) or early (N = 12) HIV infection with ≥ 2 years of suppressive ART and restarted ART if they had 2 viral loads ≥ 1,000 copies/mL after treatment interruption.RESULTSCompared with chronic-treated participants, early-treated individuals had smaller and fewer transcriptionally active HIV reservoirs. A higher percentage of HIV Gag-specific CD8+ T cell cytotoxic response was associated with lower intact proviral DNA. Predictors of HIV rebound timing differed between early- versus chronic-treated participants, as the strongest reservoir predictor of time to HIV rebound was level of residual viremia in early-treated participants and intact DNA level in chronic-treated individuals. We also identified distinct sets of pre-treatment interruption viral, immune, and inflammatory markers that differentiated participants who had rapid versus slow rebound.CONCLUSIONThe results provide an in-depth overview of the complex interplay of viral, immunologic, and inflammatory predictors of viral rebound and demonstrate that the timing of ART initiation modifies the features of rapid and slow viral rebound.TRIAL REGISTRATIONClinicalTrials.gov NCT03001128FUNDINGNIH National Institute of Allergy and Infectious Diseases, Merck.
- Published
- 2024
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25. Scoping review on communication systems used by adults with severe/profound intellectual disability for functional communication.
- Author
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Danker J, Dreyfus S, Strnadová I, and Pilkinton M
- Subjects
- Humans, Adult, Communication, Intellectual Disability
- Abstract
Background: Adults with severe/profound intellectual disability typically face poor communication outcomes as they are often nonverbal and need their supporters to provide for their communication needs. This review aimed to identify studies focused on the communication resources people with severe/profound intellectual disability use for functional communication, and the enablers and barriers to functional communication., Methods: Nine databases were systematically reviewed with keywords pertaining to the functional communication of adults with severe/profound intellectual disability. Out of 3427 identified articles, 12 met the inclusion criteria. Hand searches and ancestral searches identified another 4 articles. Out of the 16 articles, two did not meet the quality assessment criteria and were excluded. Thus, 14 articles were included in this review., Results: The findings revealed that picture exchange communication systems is the most common communication system used to support the development of functional communication. The most common functions enabled by the communication systems were choice-making and making requests. Several barriers (e.g., individual factors related to adults with severe/profound intellectual disability, others' attitudes, behaviour and knowledge) to and enablers (e.g., accessibility and availability of the communication system, training for those supporting adults with severe/profound intellectual disability) of functional communication were identified., Conclusions: Removing the barriers and enabling functional communication is essential to developing the functional communication of adults with severe/profound intellectual disability., (© 2023 The Authors. Journal of Applied Research in Intellectual Disabilities published by John Wiley & Sons Ltd.)
- Published
- 2023
- Full Text
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26. Time to Viral Rebound After Interruption of Modern Antiretroviral Therapies.
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Li JZ, Aga E, Bosch RJ, Pilkinton M, Kroon E, MacLaren L, Keefer M, Fox L, Barr L, Acosta E, Ananworanich J, Coombs R, Mellors JW, Landay AL, Macatangay B, Deeks S, Gandhi RT, and Smith DM
- Subjects
- Anti-Retroviral Agents therapeutic use, Humans, Viral Load, HIV Infections drug therapy
- Abstract
Background: Development of human immunodeficiency virus (HIV) remission strategies requires precise information on time to HIV rebound after treatment interruption, but there is uncertainty regarding whether modern antiretroviral therapy (ART) regimens and timing of ART initiation may affect this outcome., Methods: AIDS Clinical Trials Group (ACTG) A5345 enrolled individuals who initiated ART during chronic or early HIV infection and on suppressive ART for ≥2 years. Participants underwent carefully monitored antiretroviral interruption. ART was restarted upon 2 successive viral loads ≥1000 copies/mL. We compared participants of A5345 with participants of 6 historic ACTG treatment interruption studies., Results: Thirty-three chronic-treated and 12 early-treated participants interrupted ART with evaluable time to viral rebound. Median time to viral rebound ≥1000 HIV RNA copies/mL was 22 days. Acute retroviral rebound syndrome was diagnosed in 9% of the chronic-treated and none of the early-treated individuals. All participants of the historic studies were on older protease inhibitor-based regimens, whereas 97% of A5345 participants were on integrase inhibitor-based ART. There were no differences in the timing of viral rebound comparing A5345 versus historic studies. In a combined analysis, a higher percentage of early-treated participants remained off ART at posttreatment interruption week 12 (chronic vs early: 2% vs 9%, P = .0496). One chronic-treated and one early-treated A5345 participant remained off ART for >24 weeks. All participants resuppressed after ART reinitiation., Conclusions: Early ART initiation, using either older or newer ART regimens, was associated with a significant delay in the time to HIV rebound after ART interruption, lowering the barrier for HIV remission., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2022
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27. The soluble epoxide hydrolase inhibitor GSK2256294 decreases the proportion of adipose pro-inflammatory T cells.
- Author
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Mashayekhi M, Wanjalla CN, Warren CM, Simmons JD, Ghoshal K, Pilkinton M, Bailin SS, Gabriel CL, Pozzi A, Koethe JR, Brown NJ, Kalams SA, and Luther JM
- Subjects
- Adipose Tissue metabolism, Animals, Cyclohexylamines metabolism, Triazines, Epoxide Hydrolases metabolism, T-Lymphocytes metabolism
- Abstract
Adipose tissue contains a complex immune environment and is a central contributor to heightened systemic inflammation in obese persons. Epoxyeicosatrienoic acids (EETs) are lipid signaling molecules that decrease inflammation in obese animals, but their effect on inflammation in humans is unknown. The enzyme soluble epoxide hydrolase (sEH) hydrolyzes EETs to less active diols, and we hypothesized that pharmacologic sEH inhibition would decrease adipose inflammation in obese individuals. We treated obese prediabetic adults with the sEH inhibitor GSK2256294 versus placebo in a crossover design, collected subcutaneous abdominal adipose tissue via lipoaspiration and characterized the tissue T cell profile. Treatment with GSK2256294 decreased the percentage of pro-inflammatory T cells producing interferon-gamma (IFNγ), but not interleukin (IL)-17A, and decreased the amount of secreted tumor necrosis factor-alpha (TNFα). Understanding the contribution of the EET/sEH pathway to inflammation in obesity could lead to new strategies to modulate adipose and systemic inflammation., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2022
- Full Text
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28. The Proximal Airway Is a Reservoir for Adaptive Immunologic Memory in Idiopathic Subglottic Stenosis.
- Author
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Gelbard A, Wanjalla C, Wootten CT, Drake WP, Lowery AS, Wheeler DA, Cardenas MF, Sikora AG, Pathak RR, McDonnell W, Mallal S, and Pilkinton M
- Subjects
- Adult, Aged, Antigens, CD immunology, Antigens, Differentiation, T-Lymphocyte immunology, CD8 Antigens immunology, Constriction, Pathologic, Female, Glottis immunology, Glottis pathology, Humans, Immunohistochemistry, Integrin alpha Chains immunology, Lectins, C-Type immunology, Male, Middle Aged, Airway Obstruction immunology, Cicatrix immunology, Immunologic Memory immunology, Laryngostenosis immunology, T-Lymphocyte Subsets immunology
- Abstract
Objectives/hypothesis: Characterization of the localized adaptive immune response in the airway scar of patients with idiopathic subglottic stenosis (iSGS)., Study Design: Basic Science., Methods: Utilizing 36 patients with subglottic stenosis (25 idiopathic subglottic stenosis [iSGS], 10 iatrogenic post-intubation stenosis [iLTS], and one granulomatosis with polyangiitis [GPA]) we applied immunohistochemical and immunologic techniques coupled with RNA sequencing., Results: iSGS, iLTS, and GPA demonstrate a significant immune infiltrate in the subglottic scar consisting of adaptive cell subsets (T cells along with dendritic cells). Interrogation of T cell subtypes showed significantly more CD69
+ CD103+ CD8+ tissue resident memory T cells (TRM ) in the iSGS airway scar than iLTS specimens (iSGS vs. iLTS; 50% vs. 28%, P = .0065). Additionally, subglottic CD8+ clones possessed T-cell receptor (TCR) sequences with known antigen specificity for viral and intracellular pathogens., Conclusions: The human subglottis is significantly enriched for CD8+ tissue resident memory T cells in iSGS, which possess TCR sequences proven to recognize viral and intracellular pathogens. These results inform our understanding of iSGS, provide a direction for future discovery, and demonstrate immunologic function in the human proximal airway. Laryngoscope, 131:610-617, 2021., (© 2020 The American Laryngological, Rhinological and Otological Society, Inc.)- Published
- 2021
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29. Prevalence of stress urinary incontinence and intrinsic sphincter deficiency in patients with stage IV pelvic organ prolapse.
- Author
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Muñiz KS, Pilkinton M, Winkler HA, and Shalom DF
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- Aged, Female, Humans, Male, Prevalence, Retrospective Studies, Urethra, Urodynamics, Pelvic Organ Prolapse epidemiology, Urinary Incontinence, Stress epidemiology, Urinary Incontinence, Stress etiology
- Abstract
Aim: To determine the prevalence of stress urinary incontinence (SUI) and intrinsic sphincter deficiency (ISD) in women with stage IV pelvic organ prolapse., Methods: Retrospective analysis of women with stage IV prolapse who underwent multichannel urodynamic testing. Abdominal leak point pressures (ALPP) and maximum urethral closure pressures (MUCP) were recorded. ISD was defined as ALPP ≤60 cm of water and/or MUCP ≤20 cm of water. Percentages were used to present the proportion of subjects diagnosed with SUI and ISD., Results: A total of 145 patients met inclusion criteria. Mean age was 69 years; most patients were Caucasian (56%). Eighty-two (56%) patients were found to have SUI on urodynamic testing. Thirty-six (44%) of these were asymptomatic and identified as having occult SUI. Sixteen (19.5%) patients were diagnosed with ISD using ALPP and/or MUCP. Six (37%) of the ISD patients had at least one MUCP value ≤20 cm of water and 12 (75%) had observed leakage with at least one ALPP value ≤60 cm of water. The number of patients with leakage at ALPP ≤60 cm of water increased with increasing bladder volumes. Five ISD patients (31%) had ALPP ≤60 cm of water at 200 mL, six (37.5%) had ALPP ≤60 cm of water at 300 mL and seven (43.8%) had ALPP ≤60 cm of water at 400 mL., Conclusion: Greater than 50% of patients with stage IV pelvic organ prolapse had SUI on urodynamic testing, and 20% were found to have ISD. Of the patients diagnosed with SUI, 40% were asymptomatic. These findings may assist in counseling and preoperative planning for women with stage IV prolapse., (© 2020 Japan Society of Obstetrics and Gynecology.)
- Published
- 2021
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30. High Frequency of Shared Clonotypes in Human T Cell Receptor Repertoires.
- Author
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Soto C, Bombardi RG, Kozhevnikov M, Sinkovits RS, Chen EC, Branchizio A, Kose N, Day SB, Pilkinton M, Gujral M, Mallal S, and Crowe JE Jr
- Subjects
- Adult, Amino Acid Sequence, DNA genetics, Female, Genome, Human, Humans, Lymphocyte Subsets immunology, Male, Middle Aged, RNA, Messenger genetics, RNA, Messenger metabolism, Receptors, Antigen, T-Cell, alpha-beta chemistry, Young Adult, Clone Cells metabolism, Receptors, Antigen, T-Cell, alpha-beta metabolism
- Abstract
The collection of T cell receptors (TCRs) generated by somatic recombination is large but unknown. We generate large TCR repertoire datasets as a resource to facilitate detailed studies of the role of TCR clonotypes and repertoires in health and disease. We estimate the size of individual human recombined and expressed TCRs by sequence analysis and determine the extent of sharing between individual repertoires. Our experiments reveal that each blood sample contains between 5 million and 21 million TCR clonotypes. Three individuals share 8% of TCRβ- or 11% of TCRα-chain clonotypes. Sorting by T cell phenotypes in four individuals shows that 5% of naive CD4+ and 3.5% of naive CD8+ subsets share their TCRβ clonotypes, whereas memory CD4+ and CD8+ subsets share 2.3% and 0.4% of their clonotypes, respectively. We identify the sequences of these shared TCR clonotypes that are of interest for studies of human T cell biology., Competing Interests: Declaration of Interests J.E.C. has served as a consultant for Takeda Vaccines, Sanofi Pasteur, Pfizer, and Novavax; is on the scientific advisory boards of CompuVax and Meissa Vaccines; and is founder of IDBiologics, Inc., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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31. Deep sequence analysis of HIV adaptation following vertical transmission reveals the impact of immune pressure on the evolution of HIV.
- Author
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Currenti J, Chopra A, John M, Leary S, McKinnon E, Alves E, Pilkinton M, Smith R, Barnett L, McDonnell WJ, Lucas M, Noel F, Mallal S, Conrad JA, Kalams SA, and Gaudieri S
- Subjects
- Adaptation, Biological immunology, Adult, Child, Child, Preschool, Evolution, Molecular, Female, HIV Infections immunology, HIV Infections transmission, HIV-1 immunology, High-Throughput Nucleotide Sequencing, Humans, Infant, Male, Middle Aged, Adaptation, Biological genetics, HIV Infections genetics, HIV-1 genetics, Infectious Disease Transmission, Vertical
- Abstract
Human immunodeficiency virus (HIV) can adapt to an individual's T cell immune response via genomic mutations that affect antigen recognition and impact disease outcome. These viral adaptations are specific to the host's human leucocyte antigen (HLA) alleles, as these molecules determine which peptides are presented to T cells. As HLA molecules are highly polymorphic at the population level, horizontal transmission events are most commonly between HLA-mismatched donor/recipient pairs, representing new immune selection environments for the transmitted virus. In this study, we utilised a deep sequencing approach to determine the HIV quasispecies in 26 mother-to-child transmission pairs where the potential for founder viruses to be pre-adapted is high due to the pairs being haplo-identical at HLA loci. This scenario allowed the assessment of specific HIV adaptations following transmission in either a non-selective immune environment, due to recipient HLA mismatched to original selecting HLA, or a selective immune environment, mediated by matched donor/recipient HLA. We show that the pattern of reversion or fixation of HIV adaptations following transmission provides insight into the replicative cost, and likely compensatory networks, associated with specific adaptations in vivo. Furthermore, although transmitted viruses were commonly heavily pre-adapted to the child's HLA genotype, we found evidence of de novo post-transmission adaptation, representing new epitopes targeted by the child's T cell response. High-resolution analysis of HIV adaptation is relevant when considering vaccine and cure strategies for individuals exposed to adapted viruses via transmission or reactivated from reservoirs., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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32. IgG4-related disease: Association with a rare gene variant expressed in cytotoxic T cells.
- Author
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Newman JH, Shaver A, Sheehan JH, Mallal S, Stone JH, Pillai S, Bastarache L, Riebau D, Allard-Chamard H, Stone WM, Perugino C, Pilkinton M, Smith SA, McDonnell WJ, Capra JA, Meiler J, Cogan J, Xing K, Mahajan VS, Mattoo H, Hamid R, and Phillips JA 3rd
- Subjects
- Adolescent, CD4-Positive T-Lymphocytes metabolism, Genetic Variation genetics, Humans, Immunoglobulin G metabolism, Male, Middle Aged, T-Lymphocytes, Cytotoxic physiology, Immunoglobulin G genetics, Immunoglobulin G4-Related Disease genetics
- Abstract
Background: Family screening of a 48-year-old male with recently diagnosed IgG4-related disease (IgG4-RD) revealed unanticipated elevations in plasma IgG4 in his two healthy teenaged sons., Methods: We performed gene sequencing, immune cell studies, HLA typing, and analyses of circulating cytotoxic CD4+ T lymphocytes and plasmablasts to seek clues to pathogenesis. DNA from a separate cohort of 99 patients with known IgG4-RD was also sequenced for the presence of genetic variants in a specific gene, FGFBP2., Results: The three share a previously unreported heterozygous single base deletion in fibroblast growth factor binding protein type 2 (FGFBP2), which causes a frameshift in the coding sequence. The FGFBP2 protein is secreted by cytotoxic T-lymphocytes and binds fibroblast growth factor. The variant sequence in the FGFBP2 protein is predicted to form a disordered random coil rather than a helical-turn-helix structure, unable to adopt a stable conformation. The proband and the two sons had 5-10-fold higher numbers of circulating cytotoxic CD4 + T cells and plasmablasts compared to matched controls. The three members also share a homozygous missense common variant in FGFBP2 found in heterozygous form in ~40% of the population. This common variant was found in 73% of an independent, well characterized IgG4-RD cohort, showing enrichment in idiopathic IgG4-RD., Conclusions: The presence of a shared deleterious variant and homozygous common variant in FGFBP2 in the proband and sons strongly implicates this cytotoxic T cell product in the pathophysiology of IgG4-RD. The high prevalence of a common FGFBP2 variant in sporadic IgG4-RD supports the likelihood of participation in disease., (© 2019 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.)
- Published
- 2019
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33. Evidence of CD4 + T cell-mediated immune pressure on the Hepatitis C virus genome.
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Lucas M, Deshpande P, James I, Rauch A, Pfafferott K, Gaylard E, Merani S, Plauzolles A, Lucas A, McDonnell W, Kalams S, Pilkinton M, Chastain C, Barnett L, Prosser A, Mallal S, Fitzmaurice K, Drummer H, Ansari MA, Pedergnana V, Barnes E, John M, Kelleher D, Klenerman P, and Gaudieri S
- Subjects
- Alleles, CD4-Positive T-Lymphocytes virology, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes virology, Cohort Studies, Epitopes, T-Lymphocyte genetics, Epitopes, T-Lymphocyte immunology, Gene Expression Regulation, Genotype, HLA-DQ beta-Chains genetics, HLA-DQ beta-Chains immunology, HLA-DRB1 Chains genetics, HLA-DRB1 Chains immunology, Hepacivirus immunology, Hepatitis C, Chronic immunology, Hepatitis C, Chronic virology, Host-Pathogen Interactions immunology, Humans, Mutation, Viral Nonstructural Proteins immunology, CD4-Positive T-Lymphocytes immunology, Genome, Viral, Hepacivirus genetics, Hepatitis C, Chronic genetics, Host-Pathogen Interactions genetics, Viral Nonstructural Proteins genetics
- Abstract
Hepatitis C virus (HCV)-specific T cell responses are critical for immune control of infection. Viral adaptation to these responses, via mutations within regions of the virus targeted by CD8
+ T cells, is associated with viral persistence. However, identifying viral adaptation to HCV-specific CD4+ T cell responses has been difficult although key to understanding anti-HCV immunity. In this context, HCV sequence and host genotype from a single source HCV genotype 1B cohort (n = 63) were analyzed to identify viral changes associated with specific human leucocyte antigen (HLA) class II alleles, as these variable host molecules determine the set of viral peptides presented to CD4+ T cells. Eight sites across the HCV genome were associated with HLA class II alleles implicated in infection outcome in this cohort (p ≤ 0.01; Fisher's exact test). We extended this analysis to chronic HCV infection (n = 351) for the common genotypes 1A and 3A. Variation at 38 sites across the HCV genome were associated with specific HLA class II alleles with no overlap between genotypes, suggestive of genotype-specific T cell targets, which has important implications for vaccine design. Here we show evidence of HCV adaptation to HLA class II-restricted CD4+ T cell pressure across the HCV genome in chronic HCV infection without a priori knowledge of CD4+ T cell epitopes.- Published
- 2018
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34. Adipose Tissue is Enriched for Activated and Late-Differentiated CD8+ T Cells and Shows Distinct CD8+ Receptor Usage, Compared With Blood in HIV-Infected Persons.
- Author
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Koethe JR, McDonnell W, Kennedy A, Abana CO, Pilkinton M, Setliff I, Georgiev I, Barnett L, Hager CC, Smith R, Kalams SA, Hasty A, and Mallal S
- Subjects
- Adult, Anti-HIV Agents therapeutic use, CD8-Positive T-Lymphocytes chemistry, Cohort Studies, Female, HIV Infections drug therapy, Humans, Male, Middle Aged, Sequence Analysis, DNA, Sustained Virologic Response, T-Lymphocyte Subsets chemistry, Adipose Tissue pathology, Blood Cells, CD8-Positive T-Lymphocytes immunology, HIV Infections pathology, Receptors, Antigen, T-Cell analysis, T-Lymphocyte Subsets immunology
- Abstract
Background: Adverse viral and medication effects on adipose tissue contribute to the development of metabolic disease in HIV-infected persons, but T cells also have a central role modulating local inflammation and adipocyte function. We sought to characterize potentially proinflammatory T-cell populations in adipose tissue among persons on long-term antiretroviral therapy and assess whether adipose tissue CD8 T cells represent an expanded, oligoclonal population., Methods: We recruited 10 HIV-infected, non-diabetic, overweight or obese adults on efavirenz, tenofovir, and emtricitabine for >4 years with consistent viral suppression. We collected fasting blood and subcutaneous abdominal adipose tissue to measure the percentage of CD4 and CD8 T cells expressing activation, exhaustion, late differentiation/senescence, and memory surface markers. We performed T-cell receptor (TCR) sequencing on sorted CD8 cells. We compared the proportion of each T-cell subset and the TCR repertoire diversity, in blood versus adipose tissue., Results: Adipose tissue had a higher percentage of CD3CD8 T cells compared with blood (61.0% vs. 51.7%, P < 0.01) and was enriched for both activated CD8HLA-DR T cells (5.5% vs. 0.9%, P < 0.01) and late-differentiated CD8CD57 T cells (37.4% vs. 22.7%, P < 0.01). Adipose tissue CD8 T cells displayed distinct TCRβ V and J gene usage, and the Shannon Entropy index, a measure of overall TCRβ repertoire diversity, was lower compared with blood (4.39 vs. 4.46; P = 0.05)., Conclusions: Adipose tissue is enriched for activated and late-differentiated CD8 T cells with distinct TCR usage. These cells may contribute to tissue inflammation and impaired adipocyte fitness in HIV-infected persons.
- Published
- 2018
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35. Deletion of the p107/p130-binding domain of Mip130/LIN-9 bypasses the requirement for CDK4 activity for the dissociation of Mip130/LIN-9 from p107/p130-E2F4 complex.
- Author
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Sandoval R, Pilkinton M, and Colamonici OR
- Subjects
- 3T3 Cells, Animals, Binding Sites, Cell Cycle, Cell Line, Chemokine CCL4 chemistry, Chemokine CCL4 metabolism, Cyclin-Dependent Kinase 4 deficiency, Cyclin-Dependent Kinase 4 genetics, E2F4 Transcription Factor deficiency, E2F4 Transcription Factor genetics, Gene Deletion, Humans, Mice, Reverse Transcriptase Polymerase Chain Reaction, S Phase, Sequence Deletion, Tumor Suppressor Proteins chemistry, Tumor Suppressor Proteins metabolism, Chemokine CCL4 genetics, Cyclin-Dependent Kinase 4 metabolism, E2F4 Transcription Factor metabolism, Tumor Suppressor Proteins genetics
- Abstract
Mip130/LIN-9 is part of a large complex that includes homologs of the Drosophila dREAM (drosophila RB-like, E2F, and Myb) and C. elegans DRM complexes. This complex also includes proteins such as Mip40/LIN-37, Mip120/LIN-54, and LIN-52. In mammalian cells, Mip130/LIN-9 specifically associates with the p107/p130-E2F4 repressor complex in G0/G1 and with B-Myb in S-phase. However, little is known about how the transition occurs and whether Mip130/LIN-9 contributes to the repressor effect of p107/p130. In this report, we demonstrate that Mip130/LIN-9, Mip40/LIN-37, Mip120/LIN-54, and Sin3b form a core complex, the Mip Core Complex or LIN Complex (MCC/LINC), which is detectable in all phases of the cell cycle. This complex specifically recruits transcriptional repressors such as p107, p130, E2F4 and HDAC1 in G0/G1, and B-Myb in S-phase. Importantly, we provide strong evidence that the transition between repressors and activators of transcription is mediated by CDK4, through the phosphorylation of the pocket proteins, p107 and p130. The requirement for CDK4 activity is bypassed by the deletion of the first 84 amino acids (Mip130/LIN-9(Delta84)), since this mutant is unable to interact with p107/p130 in G0/G1, while maintaining its association with B-Myb. Importantly, the Mip130/LIN-9(Delta84) allele rescues the low expression of G1/S genes observed in CDK4(-/-) MEFs demonstrating that Mip130/LIN-9 contributes to the repression of these E2F-regulated genes in G0/G1.
- Published
- 2009
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36. Mip/LIN-9 can inhibit cell proliferation independent of the pocket proteins.
- Author
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Pilkinton M, Sandoval R, Barrett K, Tian X, and Colamonici OR
- Subjects
- Animals, Cell Line, Humans, Mice, Nuclear Proteins chemistry, Cell Proliferation, Cyclin-Dependent Kinase 2 metabolism, Cyclin-Dependent Kinase 4 metabolism, Cyclins metabolism, Nuclear Proteins metabolism, Tumor Suppressor Proteins metabolism
- Abstract
Progression through the G1-phase of the cell cycle requires that cyclin D and CDK4 phosphorylate pRB and the other pocket proteins, p107 and p130. Cyclin E and CDK2 further phosphorylate pRB to complete its inactivation and allow the cell to enter S-phase. These phosphorylation events lead to the inactivation of the antiproliferative effect of the pocket proteins. The pocket proteins are the main targets of CDK4, and its unregulated activity can contribute to carcinogenesis. Mip/LIN9 is a recently described protein with growth suppressor, as well as growth promoting effects due to its ability to stabilize B-Myb and induce genes required for S phase and mitosis. The finding that a mutation that deletes the first 84 amino acids of Mip/LIN-9 corrects the defects of the CDK4 knockout mouse suggests that it should have a growth repressor effect that is blocked by CDK4. However, overexpression of cyclin D only partially blocks the inhibitory effect of Mip/LIN-9 on cell proliferation. Here, we performed experiments to further understand the antiproliferative effect of Mip/LIN-9 within the context of the pocket proteins. Our results suggest that there is a pocket protein-independent mechanism of the Mip/LIN-9 antiproliferative effect since it can be observed in cells with ablation of the three members of the family, and in NIH3T3 cells expressing the adenovirus E1A-12S protein. Altogether, the independence from the pocket proteins and the partial blockade of the antiproliferative effect produced by expression of cyclin D suggest that the role of Mip/LIN-9 downstream of CDK4 may be more closely related to the activation of B-Myb and the induction of S/M genes. Importantly, the regulatory effect of CDK4 is not due to direct phosphorylation of Mip/LIN-9 by this kinase or even CDK2, suggesting an indirect mechanism such as phosphorylation of the pocket proteins.
- Published
- 2007
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37. Mip/LIN-9 regulates the expression of B-Myb and the induction of cyclin A, cyclin B, and CDK1.
- Author
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Pilkinton M, Sandoval R, Song J, Ness SA, and Colamonici OR
- Subjects
- Animals, Base Sequence, Cell Line, Tumor, Humans, Mice, Molecular Sequence Data, NIH 3T3 Cells, Nuclear Proteins, Tumor Suppressor Proteins metabolism, CDC2 Protein Kinase metabolism, Cell Cycle Proteins biosynthesis, Cyclin A physiology, Cyclin B physiology, DNA-Binding Proteins biosynthesis, Gene Expression Regulation, Trans-Activators biosynthesis, Tumor Suppressor Proteins physiology
- Abstract
Members of the novel family of proteins that include Drosophila Mip130, Caenorhabditis elegans LIN-9, and mammalian LIN-9 intervene in different cellular functions such as regulation of transcription, differentiation, transformation, and cell cycle progression. Here we demonstrate that LIN-9, designated as Mip/LIN-9, interacts with B-Myb but not with c-Myb or A-Myb. Mip/LIN-9 regulates the expression of B-Myb in a post-transcriptional manner, and its depletion not only decreases the level of the B-Myb protein but also affects the expression of S phase and mitotic genes (i.e. cyclin A, CDK1, and cyclin B). The critical role of Mip/LIN-9 on the expression of S and G(2)/M genes is further supported by the finding that coexpression of Mip/LIN-9 and B-Myb results in the activation of cyclin A and cyclin B promoter-luciferase reporters, and both proteins are detected on the cyclin A and B promoters. Interestingly, although Mip/LIN-9 promoter occupancy peaks earlier than B-Myb, the highest levels of expression of cyclins A and B correlate with the maximum binding of B-Myb to these promoters. These data support the concept that Mip/LIN-9 is required for the expression of B-Myb, and both proteins collaborate in the control of the cell cycle progression via the regulation of S phase and mitotic cyclins.
- Published
- 2007
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38. A mutant allele of BARA/LIN-9 rescues the cdk4-/- phenotype by releasing the repression on E2F-regulated genes.
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Sandoval R, Xue J, Tian X, Barrett K, Pilkinton M, Ucker DS, Raychaudhuri P, Kineman RD, Luque RM, Baida G, Zou X, Valli VE, Cook JL, Kiyokawa H, and Colamonici OR
- Subjects
- Animals, Cell Cycle, Cyclin-Dependent Kinase 4 genetics, DNA biosynthesis, E2F Transcription Factors metabolism, Embryo, Mammalian embryology, Female, Fertility genetics, Fibroblasts cytology, Gene Deletion, Gene Expression Regulation, Humans, Male, Mice, NIH 3T3 Cells, Nuclear Proteins metabolism, Ovary cytology, Phenotype, Pituitary Gland cytology, Repressor Proteins metabolism, Testis cytology, Tumor Suppressor Proteins metabolism, Alleles, Caenorhabditis elegans Proteins genetics, Caenorhabditis elegans Proteins metabolism, Cyclin-Dependent Kinase 4 deficiency, E2F Transcription Factors antagonists & inhibitors, Mutation genetics, Repressor Proteins antagonists & inhibitors
- Abstract
It has been proposed that C. elegans LIN-9 functions downstream of CDK4 in a pathway that regulates cell proliferation. Here, we report that mammalian BARA/LIN-9 is a predominantly nuclear protein that inhibits cell proliferation. More importantly, we demonstrate that BARA/LIN-9 also acts downstream of cyclin D/CDK4 in mammalian cells since (i) its antiproliferative effect is partially blocked by coexpression of cyclin D1, and (ii) a mutant form that lacks the first 84 amino acids rescues several phenotypic alterations observed in mice null for cdk4. Interestingly, mutation of BARA/LIN-9 restores the expression of E2F target genes in CDK4 null MEFs, indicating that the wild-type protein plays a role in the expression of genes required for the G1/S transition.
- Published
- 2006
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39. Different requirements for the cytostatic and apoptotic effects of type I interferons. Induction of apoptosis requires ARF but not p53 in osteosarcoma cell lines.
- Author
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Sandoval R, Xue J, Pilkinton M, Salvi D, Kiyokawa H, and Colamonici OR
- Subjects
- Animals, Cell Division, Cell Line, Tumor, Dose-Response Relationship, Drug, Fibroblasts metabolism, Genes, Dominant, Genetic Vectors, Humans, Immunoblotting, Interferon-alpha metabolism, Interferon-beta metabolism, Mice, Mice, Inbred C57BL, Mutation, Precipitin Tests, Time Factors, Transgenes, Tubulin metabolism, Tumor Suppressor Protein p14ARF metabolism, Tumor Suppressor Protein p53 metabolism, Apoptosis, Interferons metabolism, Osteosarcoma metabolism, Tumor Suppressor Protein p14ARF physiology, Tumor Suppressor Protein p53 physiology
- Abstract
The regulation of cell growth is one of the most important effects of type I interferons (IFNs). This response may involve a cytostatic effect or the induction of apoptosis depending on the cell context. Often the growth-inhibitory response of type I IFNs is studied in tumor cell lines carrying mutations of tumor suppressor genes, and therefore, the growth-inhibitory effect can be influenced by inactivation of these important regulators of cell proliferation. In this report, we explored the role of the ARF-p53 pathway in the growth-inhibitory effect of type I IFNs. We found that p53 is only induced in cells that express p14(ARF) (p19(ARF) in mouse cells). Surprisingly, mouse embryonal fibroblasts that are null for p19(ARF) or P53, even after transformation with oncogenic RAS, respond as well as wild type to the growth-inhibitory effect of type I IFNs. Similarly, human ARF(-/-) U2OS and P53(-/-) SAOS-2 cells show a significant decrease in cell proliferation. However, only SAOS-2 or U2OS reconstituted with inducible p14(ARF) undergo apoptosis in response to IFN beta treatment, and this effect was not inhibited by expression of dominant negative p53. These data suggest that (i) at least in specific cell types, the induction of apoptosis by type I IFNs requires an ARF pathway that is p53-independent and (ii) the cytostatic and pro-apoptotic effects of type I IFNs employ different pathways.
- Published
- 2004
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40. Comparative analysis of EspF from enteropathogenic and enterohemorrhagic Escherichia coli in alteration of epithelial barrier function.
- Author
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Viswanathan VK, Koutsouris A, Lukic S, Pilkinton M, Simonovic I, Simonovic M, and Hecht G
- Subjects
- Bacterial Adhesion, Caco-2 Cells, Cell Line, Tumor, Epithelial Cells cytology, Escherichia coli classification, Escherichia coli genetics, Escherichia coli Proteins genetics, Gene Expression Regulation, Bacterial, Humans, Intestines cytology, Intestines microbiology, Microscopy, Fluorescence, Molecular Chaperones metabolism, Tight Junctions physiology, Virulence, Epithelial Cells pathology, Escherichia coli pathogenicity, Escherichia coli Proteins metabolism, Intestines pathology, Tight Junctions pathology
- Abstract
Enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) are related intestinal pathogens that harbor highly similar pathogenicity islands known as the locus of enterocyte effacement (LEE). Despite their genetic similarity, these two pathogens disrupt epithelial tight junction barrier function with distinct kinetics. EHEC-induced reduction in transepithelial electrical resistance (TER), a measure of barrier function disruption, is significantly slower and more modest in comparison to that induced by EPEC. The variation in bacterial adherence only partially accounted for these differences. The LEE-encoded effector protein EspF has been shown to be critical for EPEC-induced alterations in TER. EspF from both EPEC and EHEC is expressed and secreted upon growth in tissue culture medium. The mutation of EHEC cesF suggested that the optimal expression and secretion of EHEC EspF required its chaperone CesF, as has been shown for EPEC. In contrast to EPEC espF and cesF, mutation of the corresponding EHEC homologs did not dramatically alter the decrease in TER. These differences could possibly be explained by the presence of additional espF-like sequences (designated U- and M-espF, where the letter designations refer to the specific cryptic prophage sequences on the EHEC chromosome closest to the respective genes) in EHEC. Reverse transcription-PCR analyses revealed coordinate regulation of EHEC U-espF and the LEE-encoded espF, with enhanced expression in bacteria grown in Dulbecco-Vogt modified Eagle's medium compared to bacteria grown in Luria broth. Both EHEC espF and U-espF complemented an EPEC espF deletion strain for barrier function alteration. The overexpression of U-espF, but not espF, in wild-type EHEC potentiated the TER response. These studies reveal further similarities and differences in the pathogenesis of EPEC and EHEC.
- Published
- 2004
- Full Text
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