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Graves KJ, Ghosh AP, Schmidt N, Augostini P, Secor WE, Schwebke JR, Martin DH, Kissinger PJ, Muzny CA. Trichomonas vaginalis Virus Among Women With Trichomoniasis and Associations With Demographics, Clinical Outcomes, and Metronidazole Resistance. Clin Infect Dis 2020; 69:2170-2176. [PMID: 30768180 DOI: 10.1093/cid/ciz146] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 02/12/2019] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Trichomonas vaginalis virus (TVV) is a non-segmented, 4.5-5.5 kilo-base pair (kbp), double-stranded RNA virus infecting T. vaginalis. The objectives of this study were to examine the TVV prevalence in US Trichomonas vaginalis isolates and TVV's associations with patient demographics, clinical outcomes, and metronidazole resistance. METHODS Archived T. vaginalis isolates from the enrollment visits of 355 women participating in a T. vaginalis treatment trial in Birmingham, Alabama, were thawed and grown in culture. Their total RNA was extracted using a Trizol reagent. Contaminating, single-stranded RNA was precipitated using 4.0 M Lithium Chloride and centrifugation. The samples were analyzed by gel electrophoresis to visualize a 4.5 kbp band representative of TVV. In vitro testing for metronidazole resistance was also performed on 25/47 isolates obtained from the women's test of cure visits. RESULTS TVV was detected in 142/355 (40%) isolates at the enrollment visit. Women with TVV-positive (TVV+) isolates were significantly older (P = .01), more likely to smoke (P = .04), and less likely to report a history of gonorrhea (P = .04). There was no association between the presence of clinical symptoms or repeat T. vaginalis infections with TVV+ isolates (P = .14 and P = .44, respectively). Of 25 test of cure isolates tested for metronidazole resistance, 0/10 TVV+ isolates demonstrated resistance, while 2/15 TVV-negative isolates demonstrated mild to moderate resistance (P = .23). CONCLUSIONS Of 355 T. vaginalis isolates tested for TVV, T. vaginalis isolates tested for TVV, the prevalence was 40%. However, there was no association of TVV+ isolates with clinical symptoms, repeat infections, or metronidazole resistance. These results suggest that TVV may be commensal to T. vaginalis.
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Kundu A, Shelar S, Ghosh AP, Ballestas MP, Kirkman RP, Nam HY, Brinkley GJ, Karki S, Mobley JA, Varambally S, Sudarshan S. Dynamic Regulation of TET2 by Phosphorylation and Dephosphorylation at Ser99. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.02033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kundu A, Shelar S, Ghosh AP, Ballestas M, Kirkman R, Nam H, Brinkley GJ, Karki S, Mobley JA, Bae S, Varambally S, Sudarshan S. 14-3-3 proteins protect AMPK-phosphorylated ten-eleven translocation-2 (TET2) from PP2A-mediated dephosphorylation. J Biol Chem 2020; 295:1754-1766. [PMID: 31901078 PMCID: PMC7008385 DOI: 10.1074/jbc.ra119.011089] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/19/2019] [Indexed: 11/06/2022] Open
Abstract
Ten-eleven translocation-2 (TET2) is a member of the methylcytosine dioxygenase family of enzymes and has been implicated in cancer and aging because of its role as a global epigenetic modifier. TET2 has a large N-terminal domain and a catalytic C-terminal region. Previous reports have demonstrated that the TET2 catalytic domain remains active independently of the N-terminal domain. As such, the function of the N terminus of this large protein remains poorly characterized. Here, using yeast two-hybrid screening, co-immunoprecipitation, and several biochemical assays, we found that several isoforms of the 14-3-3 family of proteins bind TET2. 14-3-3 proteins bound TET2 when it was phosphorylated at Ser-99. In particular, we observed that AMP-activated protein kinase-mediated phosphorylation at Ser-99 promotes TET2 stability and increases global DNA 5-hydroxymethylcytosine levels. The interaction of 14-3-3 proteins with TET2 protected the Ser-99 phosphorylation, and disruption of this interaction both reduced TET2 phosphorylation and decreased TET2 stability. Furthermore, we noted that protein phosphatase 2A can interact with TET2 and dephosphorylate Ser-99. Collectively, these results provide detailed insights into the role of the TET2 N-terminal domain in TET2 regulation. Moreover, they reveal the dynamic nature of TET2 protein regulation that could have therapeutic implications for disease states resulting from reduced TET2 levels or activity.
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Graves KJ, Ghosh AP, Kissinger PJ, Muzny CA. Trichomonas vaginalis virus: a review of the literature. Int J STD AIDS 2019; 30:496-504. [PMID: 30626281 DOI: 10.1177/0956462418809767] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Trichomonas vaginalis (TV) is a parasitic protozoan responsible for the sexually transmitted infection trichomoniasis. Trichomonas vaginalis virus (TVV) is a nonsegmented, 4.5-5 kbp, double-stranded RNA virus, from the Totiviridae family, which inhabits TV. A capsid protein consisting of 120 subunits is covered in channels aiding in RNA release. TVV is closely associated with the Golgi complex and is transmitted vertically. TVV has four subspecies, TVV1, TVV2, TVV3, and TVV4. The clinical significance of TVV and its effect on the pathogenicity of TV is not well known. We performed a systematic review of the literature on TVV to better understand its clinical significance and its role in the pathogenesis of TV.
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Ghosh AP, Marshall CB, Coric T, Shim EH, Kirkman R, Ballestas ME, Ikura M, Bjornsti MA, Sudarshan S. Point mutations of the mTOR-RHEB pathway in renal cell carcinoma. Oncotarget 2016; 6:17895-910. [PMID: 26255626 PMCID: PMC4627224 DOI: 10.18632/oncotarget.4963] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 07/03/2015] [Indexed: 01/21/2023] Open
Abstract
Aberrations in the mTOR (mechanistic target of rapamycin) axis are frequently reported in cancer. Using publicly available tumor genome sequencing data, we identified several point mutations in MTOR and its upstream regulator RHEB (Ras homolog enriched in brain) in patients with clear cell renal cell carcinoma (ccRCC), the most common histology of kidney cancer. Interestingly, we found a prominent cluster of hyperactivating mutations in the FAT (FRAP-ATM-TTRAP) domain of mTOR in renal cell carcinoma that led to an increase in both mTORC1 and mTORC2 activities and led to an increased proliferation of cells. Several of the FAT domain mutants demonstrated a decreased binding of DEPTOR (DEP domain containing mTOR-interacting protein), while a subset of these mutations showed altered binding of the negative regulator PRAS40 (proline rich AKT substrate 40). We also identified a recurrent mutation in RHEB in ccRCC patients that leads to an increase in mTORC1 activity. In vitro characterization of this RHEB mutation revealed that this mutant showed considerable resistance to TSC2 (Tuberous Sclerosis 2) GAP (GTPase activating protein) activity, though its interaction with TSC2 remained unaltered. Mutations in the FAT domain of MTOR and in RHEB remained sensitive to rapamycin, though several of these mutations demonstrated residual mTOR kinase activity after treatment with rapamycin at clinically relevant doses. Overall, our data suggests that point mutations in the mTOR pathway may lead to downstream mTOR hyperactivation through multiple different mechanisms to confer a proliferative advantage to a tumor cell.
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Ghosh AP, Sudarshan S. Genetics of renal cancer: focus on MTOR. Aging (Albany NY) 2016; 8:421-2. [PMID: 27017990 PMCID: PMC4833135 DOI: 10.18632/aging.100937] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 03/25/2016] [Indexed: 11/27/2022]
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Shim EH, Livi CB, Rakheja D, Tan J, Benson D, Parekh V, Kho EY, Ghosh AP, Kirkman R, Velu S, Dutta S, Chenna B, Rea SL, Mishur RJ, Li Q, Johnson-Pais TL, Guo L, Bae S, Wei S, Block K, Sudarshan S. L-2-Hydroxyglutarate: an epigenetic modifier and putative oncometabolite in renal cancer. Cancer Discov 2014; 4:1290-8. [PMID: 25182153 DOI: 10.1158/2159-8290.cd-13-0696] [Citation(s) in RCA: 203] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
UNLABELLED Through unbiased metabolomics, we identified elevations of the metabolite 2-hydroxyglutarate (2HG) in renal cell carcinoma (RCC). 2HG can inhibit 2-oxoglutaratre (2-OG)-dependent dioxygenases that mediate epigenetic events, including DNA and histone demethylation. 2HG accumulation, specifically the d enantiomer, can result from gain-of-function mutations of isocitrate dehydrogenase (IDH1, IDH2) found in several different tumors. In contrast, kidney tumors demonstrate elevations of the l enantiomer of 2HG (l-2HG). High-2HG tumors demonstrate reduced DNA levels of 5-hydroxymethylcytosine (5hmC), consistent with 2HG-mediated inhibition of ten-eleven translocation (TET) enzymes, which convert 5-methylcytosine (5mC) to 5hmC. l-2HG elevation is mediated in part by reduced expression of l-2HG dehydrogenase (L2HGDH). L2HGDH reconstitution in RCC cells lowers l-2HG and promotes 5hmC accumulation. In addition, L2HGDH expression in RCC cells reduces histone methylation and suppresses in vitro tumor phenotypes. Our report identifies l-2HG as an epigenetic modifier and putative oncometabolite in kidney cancer. SIGNIFICANCE Here, we report elevations of the putative oncometabolite l-2HG in the most common subtype of kidney cancer and describe a novel mechanism for the regulation of DNA 5hmC levels. Our findings provide new insight into the metabolic basis for the epigenetic landscape of renal cancer.
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Ghosh AP, Klocke BJ, Ballestas ME, Roth KA. CHOP potentially co-operates with FOXO3a in neuronal cells to regulate PUMA and BIM expression in response to ER stress. PLoS One 2012; 7:e39586. [PMID: 22761832 PMCID: PMC3386252 DOI: 10.1371/journal.pone.0039586] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 05/28/2012] [Indexed: 12/23/2022] Open
Abstract
Endoplasmic reticulum (ER) stress-induced apoptosis has been implicated in various neurodegenerative diseases including Parkinson Disease, Alzheimer Disease and Huntington Disease. PUMA (p53 upregulated modulator of apoptosis) and BIM (BCL2 interacting mediator of cell death), pro-apoptotic BH3 domain-only, BCL2 family members, have previously been shown to regulate ER stress-induced cell death, but the upstream signaling pathways that regulate this response in neuronal cells are incompletely defined. Consistent with previous studies, we show that both PUMA and BIM are induced in response to ER stress in neuronal cells and that transcriptional induction of PUMA regulates ER stress-induced cell death, independent of p53. CHOP (C/EBP homologous protein also known as GADD153; gene name Ddit3), a critical initiator of ER stress-induced apoptosis, was found to regulate both PUMA and BIM expression in response to ER stress. We further show that CHOP knockdown prevents perturbations in the AKT (protein kinase B)/FOXO3a (forkhead box, class O, 3a) pathway in response to ER stress. CHOP co-immunoprecipitated with FOXO3a in tunicamycin treated cells, suggesting that CHOP may also regulate other pro-apoptotic signaling cascades culminating in PUMA and BIM activation and cell death. In summary, CHOP regulates the expression of multiple pro-apoptotic BH3-only molecules through multiple mechanisms, making CHOP an important therapeutic target relevant to a number of neurodegenerative conditions.
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Ghosh AP, Cape JD, Klocke BJ, Roth KA. Deficiency of pro-apoptotic Hrk attenuates programmed cell death in the developing murine nervous system but does not affect Bcl-x deficiency-induced neuron apoptosis. J Histochem Cytochem 2011; 59:976-83. [PMID: 22043021 DOI: 10.1369/0022155411424311] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The BCL-2 family includes both pro- and anti-apoptotic proteins, which regulate programmed cell death during development and in response to various apoptotic stimuli. The BH3-only subgroup of pro-apoptotic BCL-2 family members is critical for the induction of apoptotic signaling, by binding to and neutralizing anti-apoptotic BCL-2 family members. During embryonic development, the anti-apoptotic protein BCL-X(L) plays a critical role in the survival of neuronal populations by regulating the multi-BH domain protein BAX. In this study, the authors investigated the role of Harakiri (HRK), a relatively recently characterized BH3-only molecule in disrupting the BAX-BCL-X(L) interaction during nervous system development. Results indicate that HRK deficiency significantly reduces programmed cell death in the nervous system. However, HRK deficiency does not significantly attenuate the widespread apoptosis seen in the Bcl-x (-/-) embryonic nervous system, indicating that other BH3-only molecules, alone or in combination, may regulate BAX activation in immature neurons.
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Walls KC, Ghosh AP, Franklin AV, Klocke BJ, Ballestas M, Shacka JJ, Zhang J, Roth KA. Lysosome dysfunction triggers Atg7-dependent neural apoptosis. J Biol Chem 2010; 285:10497-507. [PMID: 20123985 DOI: 10.1074/jbc.m110.103747] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Macroautophagy (autophagy) is a process wherein bulk cytosolic proteins and damaged organelles are sequestered and degraded via the lysosome. Alterations in autophagy-associated proteins have been shown to cause neural tube closure defects, neurodegeneration, and tumor formation. Normal lysosome function is critical for autophagy completion and when altered may lead to an accumulation of autophagic vacuoles (AVs) and caspase activation. The tumor suppressor p53 is highly expressed in neural precursor cells (NPCs) and has an important role in the regulation of both autophagy and apoptosis. We hypothesized that altered lysosome function would lead to NPC death via an interaction between autophagy- and apoptosis-associated proteins. To test our hypothesis, we utilized FGF2-expanded NPCs and the neural stem cell line, C17.2, in combination with the lysosomotropic agent chloroquine (CQ) and the vacuolar ATPase inhibitor bafilomycin A1 (Baf A1). Both CQ and Baf A1 caused concentration- and time-dependent AV accumulation, p53 phosphorylation, increased damage regulator autophagy modulator levels, caspase-3 activation, and cell death. Short hairpin RNA knockdown of Atg7, but not Beclin1, expression significantly inhibited CQ- and Baf A1-induced cell death, indicating that Atg7 is an upstream mediator of lysosome dysfunction-induced cell death. Cell death and/or caspase-3 activation was also attenuated by protein synthesis inhibition, p53 deficiency, or Bax deficiency, indicating involvement of the intrinsic apoptotic death pathway. In contrast to lysosome dysfunction, starvation-induced AV accumulation was inhibited by either Atg7 or Beclin1 knockdown, and Atg7 knockdown had no effect on starvation-induced death. These findings indicate that Atg7- and Beclin1-induced autophagy plays a cytoprotective role during starvation but that Atg7 has a unique pro-apoptotic function in response to lysosome dysfunction.
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Geng Y, Walls KC, Ghosh AP, Akhtar RS, Klocke BJ, Roth KA. Cytoplasmic p53 and activated Bax regulate p53-dependent, transcription-independent neural precursor cell apoptosis. J Histochem Cytochem 2009; 58:265-75. [PMID: 19901272 DOI: 10.1369/jhc.2009.954024] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The prodeath effects of p53 are typically mediated via its transcriptional upregulation of proapoptotic Bcl-2 family members, including PUMA, Noxa, and/or Bax. We previously reported that staurosporine (STS), a broad-spectrum kinase inhibitor and prototypical apoptosis-inducing agent, produced p53-dependent, Bax-dependent, neural precursor cell (NPC) apoptosis, but that this effect occurred independently of new gene transcription and PUMA expression. To further characterize the mechanism by which p53 regulates NPC death, we used primary cerebellar NPCs derived from wild-type, p53-deficient, and Bax-deficient neonatal mice and the mouse cerebellar neural stem cell line, C17.2. We found that STS rapidly increased p53 cytoplasmic immunoreactivity in neuritic-like processes in C17.2 cells, which preceded Bax activation and caspase-3 cleavage. Confocal microscopy analysis of STS-treated cells revealed partial colocalization of p53 with the mitochondrial marker pyruvate dehydrogenase as well as with conformationally altered "activated" Bax, suggesting an interaction between these proapoptotic molecules in triggering apoptotic death. Nucleophosmin (NPM), a CRM1-dependent nuclear chaperone, also exhibited partial colocalization with both activated Bax and p53 following STS treatment. These observations suggest that cytoplasmic p53 can trigger transcription-independent NPC apoptosis through its potential interaction with NPM and activated Bax.
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Chatterjee S, Ghosh AP, Barbhuiya J, Dey SK. Adverse cutaneous drug reactions: A one year survey at a dermatology outpatient clinic of a tertiary care hospital. Indian J Pharmacol 2006. [DOI: 10.4103/0253-7613.28212] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Banerjee K, Barbhuiya JN, Ghosh AP, Dey SK, Karmakar PR. The efficacy of low-dose oral corticosteroids in the treatment of vitiligo patient. Indian J Dermatol Venereol Leprol 2003; 69:135-7. [PMID: 17642858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Autoimmunity is one of the most probable pathogenesis of vitiligo. Systemic corticosteroids may arrest the progression of vitiligo and lead to repigmentation by suppressing immunity. The clinical efficacy of low-dose oral corticosteroids was assessed to minimize the side-effects in actively spreading vitiligo patients. One hundred (100) patients with vitiligo were evaluated. The patients took daily doses of oral prednisolone (0.3 mg/kg body weight) initially as a single oral dose after breakfast for the first 2 months. The dosage was then reduced to half the initial dose during the 3rd month and was halved again for the 4th and final month. After 4 months of treatment, 76% showed repigmentation while the arrest of progression (both repigmentation and stationary) was noted in 90% of patients. Male sex, and patients under 15 years of age showed pronounced repigmentation with statistical significance. According to this study low-dose oral prednisolone is an effective method in preventing progression and inducing repigmentation of fast-spreading vitiligo without the associated serious side-effects.
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Walkup RE, Avouris P, Ghosh AP. Positive-ion production by electron bombardment of alkali halides. PHYSICAL REVIEW. B, CONDENSED MATTER 1987; 36:4577-4580. [PMID: 9943468 DOI: 10.1103/physrevb.36.4577] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Walkup RE, Avouris P, Ghosh AP. Excited-atom production by electron bombardment of alkali halides. PHYSICAL REVIEW LETTERS 1986; 57:2227-2230. [PMID: 10033668 DOI: 10.1103/physrevlett.57.2227] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Holbrow CH, Ghosh AP, Heinzen D, Zhu X, Quivers WW, Shimkaveg G, Pappas PG, Thomas JE, Feld MS. Complete Doppler coverage in laser optical pumping by wall-induced velocity-changing collisions. PHYSICAL REVIEW. A, GENERAL PHYSICS 1986; 34:2477-2479. [PMID: 9897539 DOI: 10.1103/physreva.34.2477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Thomas JE, Ghosh AP, Attili MA. Isolated multipole echoes for study of anisotropic moment collision kernels. PHYSICAL REVIEW. A, GENERAL PHYSICS 1986; 33:3029-3046. [PMID: 9897011 DOI: 10.1103/physreva.33.3029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Ghosh AP, Nabors CD, Attili MA, Thomas JE. 3P1-orientation velocity-changing collision kernels studied by isolated multipole echoes. PHYSICAL REVIEW LETTERS 1985; 54:1794-1797. [PMID: 10031142 DOI: 10.1103/physrevlett.54.1794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Khan MN, Mirel RD, Ontjes DA, Ghosh AP, Lazarus LH, DiAugustine RP. Adrenocorticotropin radioimmunoassay: properties of antisera against synthetic ACTH(1-24) and its clinical application. HORMONE RESEARCH 1984; 20:129-37. [PMID: 6092254 DOI: 10.1159/000179985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Two antisera against synthetic ACTH(1-24) developed in rabbit showed strikingly different affinities toward the ACTH molecule. Both antisera (A-6 and A-7) were highly specific for the COOH-terminal region of ACTH(1-24). Antisera A-6 recognized ACTH(1-39) poorly. Radioimmunoassays (RIAs) using these antisera permitted the rapid (less than or equal to 18 h) quantitation of ACTH(1-24) (A-6) or ACTH(1-39) (A-7) at picogram levels. ACTH levels were determined on silicic acid extracts of rat and human plasma samples by the RIA specific for mid-region of ACTH(1-39) (A-7) and compared with that obtained by an ACTH(34-39) (C-terminal) RIA. In nearly all cases the C-terminal/mid-region ACTH ratios were less than 1.0, indicating that C-terminus of ACTH is more readily degraded by tissue or blood peptidases than are internal sequences. A solid-phase immunoadsorbent RIA specific for the extreme COOH-terminus of ACTH(1-24) was developed by coupling antiserum (A-6) to Sepharose 4B. This assay exhibited the same specificity as the soluble antiserum, yet tolerated relatively high concentrations of protein. Although the assay was suitable for rapid quantitation of ACTH(1-24), a decrease in sensitivity was observed in comparison to a conventional assay.
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