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Kong H, Dong C, Jing W, Tian Z, Zheng M, Wang C, Hou Q, Cheng Y, Zhang L, Jiang X, Luo L, Zhu S. The Role of Tyramine β-Hydroxylase in Density Dependent Immunityof Oriental Armyworm ( Mythmina separata) Larva. Int J Mol Sci 2019; 20:ijms20071553. [PMID: 30925699 PMCID: PMC6480284 DOI: 10.3390/ijms20071553] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/22/2019] [Accepted: 03/26/2019] [Indexed: 11/16/2022] Open
Abstract
High population density alters insect prophylactic immunity, with density-dependent prophylaxis (DDP) being reported in many polyphonic insects. However, the molecular mechanism for DDP remains unclear. In current study, the role of tyramine β-hydroxylase (Tβh) in the immune response of M. separata larvae that were subject to different rearing densities conditions was investigated. The tyramine β-hydroxylase activity of larvae from high density treatments (10 and 30 larvae per jar) was significantly higher than that of the larvae from low density treatments (one, two, and five larvae/jar). A tyramine β-hydroxylase (designated MsTβh) containing a 1779 bp open reading frame was identified. Multiple sequence alignment and phylogenetic analysis indicated that MsTβh was orthologous to the Tβh that was found in other lepidopterans. Elevated MsTβh expression was observed in larvae under high density (10 larvae per jar). Silencing MsTβh expression by the injection of dsRNA in larvae from the high density treatment produced a 25.1% reduction in octopamine levels, while at the same time, there was a significant decrease in phenoloxidase (PO) and lysozyme activity, total haemocyte counts, and survival against Beauveria infection 56.6%, 88.5%, 82.0%, and 55.8%, respectively, when compared to control larvae. Our findings provide the first insights into how MsTβh mediates the octopamine level, which in turn modulates the immune response of larvae under different population densities.
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Lagos C, Carvajal P, Castro I, Jara D, González S, Aguilera S, Barrera MJ, Quest AFG, Bahamondes V, Molina C, Urzúa U, Hermoso MA, Leyton C, González MJ. Association of high 5-hydroxymethylcytosine levels with Ten Eleven Translocation 2 overexpression and inflammation in Sjögren's syndrome patients. Clin Immunol 2018; 196:85-96. [PMID: 29894742 DOI: 10.1016/j.clim.2018.06.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/07/2018] [Accepted: 06/07/2018] [Indexed: 12/17/2022]
Abstract
Here, we determined the 5-hydroxymethylcytosine (5hmC), 5-methylcytosine (5mC), Ten Eleven Translocation (TETs), and DNA methyltransferases (DNMTs) levels in epithelial and inflammatory cells of labial salivary glands (LSG) from Sjögren's syndrome (SS)-patients and the effect of cytokines on HSG cells. LSG from SS-patients, controls and HSG cells incubated with cytokines were analysed. Levels of 5mC, 5hmC, DNMTs, TET2 and MeCP2 were assessed by immunofluorescence. In epithelial cells from SS-patients, an increase in TET2, 5hmC and a decrease in 5mC and MeCP2 were observed, additionally, high levels of 5mC and DNMTs and low levels of 5hmC were detected in inflammatory cells. Cytokines increased TET2 and 5hmC and decreased 5mC levels. Considering that the TET2 gene.promoter contains response elements for transcription factors activated by cytokines, together to in vitro results suggest that changes in DNA hydroxymethylation, resulting from altered levels of TET2 are likely to be relevant in the Sjögren's syndrome etiopathogenesis.
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Zhang R, Wang Y, Chen L, Wang R, Li C, Li X, Fang B, Ren X, Ruan M, Liu J, Xiong Q, Zhang L, Jin Y, Zhang M, Liu X, Li L, Chen Q, Pan D, Li R, Cooper DKC, Yang H, Dai Y. Reducing immunoreactivity of porcine bioprosthetic heart valves by genetically-deleting three major glycan antigens, GGTA1/β4GalNT2/CMAH. Acta Biomater 2018; 72:196-205. [PMID: 29631050 DOI: 10.1016/j.actbio.2018.03.055] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 03/23/2018] [Accepted: 03/30/2018] [Indexed: 02/07/2023]
Abstract
Bioprosthetic heart valves (BHVs) originating from pigs are extensively used for heart valve replacement in clinics. However, recipient immune responses associated with chronic calcification lead to structural valve deterioration (SVD) of BHVs. Two well-characterized epitopes on porcine BHVs have been implicated in SVD, including galactose-α1,3-galactose (αGal) and N-glycolylneuraminic acid (Neu5Gc) whose synthesis are catalyzed by α(1,3) galactosyltransferase (encoded by the GGTA1 gene) and CMP-Neu5Ac hydroxylase (encoded by the CMAH gene), respectively. It has been reported that BHV from αGal-knockout pigs are associated with a significantly reduced immune response by human serum. Moreover, valves from αGal/Neu5Gc-deficient pigs could further reduce human IgM/IgG binding when compared to BHV from αGal-knockout pigs. Recently, another swine xenoantigen, Sd(a), produced by β-1,4-N-acetyl-galactosaminyl transferase 2 (β4GalNT2), has been identified. To explore whether tissue from GGTA1, CMAH, and β4GalNT2 triple gene-knockout (TKO) pigs would further minimize human antibody binding to porcine pericardium, TKO pigs were successfully produced by CRISPR/Cas9 mediated gene targeting. Our results showed that the expression of αGal, Neu5G and Sd(a) on TKO pigs was negative, and that human IgG/IgM binding to pericardium was minimal. Moreover, the analysis of collagen composition and physical characteristics of porcine pericardium from the TKO pigs indicated that elimination of the three xenoantigens had no significant impact on the physical proprieties of porcine pericardium. Our results demonstrated that TKO pigs would be an ideal source of BHVs. STATEMENT OF SIGNIFICANCE Surgical heart valve replacement is an established lifesaving treatment for diseased heart valve. Bioprosthetic heart valves (BHVs) made from glutaraldehyde-fixed porcine or bovine tissues are widely used in clinics but exhibit age-dependent structural valve degeneration (SVD) which is associated with the immune response against BHVs. Three major xenoantigens present on commercial BHVs, Galactosea α1,3 galactose (αGal), N-glycolylneuraminic acid (Neu5Gc) and glycan products of β-1,4-N-acetyl-galactosaminyl transferase 2 (β4GalNT2) are eliminated through CRISPR/Cas9 mediated gene targeting in the present study. The genetically modified porcine pericardium showed reduced immunogenicity but comparable collagen composition and physical characteristics of the pericardium from wild-type pigs. Our data suggested that BHVs from TKO pigs is a promising alternative for currently available BHVs from wild-type pigs.
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Huyan T, Yin D, Wang W, Song K, Wang Y, Lu H, Yang H, Xue X. [Expression of human aspartyl beta-hydroxylase and preparation of its monoclonal antibody]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2011; 27:659-666. [PMID: 21848003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We investigated the mechanism of human aspartyl beta-hydroxylase (HAAH) in early diagnosis of tumors. The encoding gene of HAAH was cloned from the hepatic carcinoma by RT-PCR and expressed as a fused protein in the prokaryotic vector pBV-IL1. The expressed HAAH was purified by Ni(2+)-NTA purification column and the purified protein was then used to immunize Balb/c mice. Three hybridoma cell lines (respectively designated H3/E10, E4/F12 and G4/D8) stably expressing the monoclonal antibody specific to HAAH fusion protein were obtained. The specificity and sensitivity of the monoclonal antibody were assessed by indirect enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. Finally, the monoclonal antibody expressed by H3/E10 cell line was used to detect the expression of HAAH in several tumor cell lines by indirect immuno-fluorescence, and the specific fluorescence was observed. In conclusion, this study successfully constructed the recombinant prokaryotic vector pBV-IL1-HAAH and prepared HAAH-specific monoclonal antibody for further study of the structure and function of the protein. The result may also lay solid foundation for the research of the molecular mechanism of HAAH in early diagnosis of tumors.
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Wang H, Xue XP, Lei YF, Song K, Hu YT, Wang W, Yang H. [Cloning of the variable region genes from hybridoma against HAAH and then construction and expression of anti-HAAH scFv]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2010; 26:467-470. [PMID: 20423655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
AIM Construction and expression of anti-HAAH single chain variable fragment (scFv) by cloning of the variable region genes from anti-HAAH hybridoma cells G3/F11. METHODS Total RNA was extracted from hybridoma cells G3/F11. By RT-PCR, murine V(H) and V(L) genes of mAb were amplified respectively. Then, They were assembled into V(H)-linker-V(L) scFv template by SOE-PCR and anti-HAAH scFv was express in E.coli by constructed pHEN 1-anti-HAAH vector. The expression of anti-HAAH scFv were detected by SDS-PAGE and Western blotting and the binding activity were demonstrated by ELISA. RESULTS The analysis of DNA sequencing shown that the full-length of constructed scFv gene was 744 bp, encoding 248 amino acids. Moreover, the V(H) and V(L) genes were functional antibody variable region genes, as there were four FRs and three CDRs in both of them. By SDS-PAGE and Western blotting, the expression level of anti-HAAH scFv were detected. The expression level of pHEN 1-anti-HAAH scFv, which was expressed in E.coli HB2151, was 7.8% in total E.coli protein and were existed in soluble protein mainly. By indirect ELISA detection with HAAH protein, the binding activity of soluble anti-HAAH scFv was very well. CONCLUSION The murine V(H) and V(L) genes of mAb against HAAH have been cloned successfully and anti-HAAH scFv have been constructed and expressed. Besides, the scFv could be further studied about their biological activity and application, due to their high affinity shown in preliminary detection.
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Tseĭlikman VE, Kozochkin DA, Markel' AL, Tseĭlikman OB, Sibiriak SV, Sinitskiĭ AI, Sysakov DA, Simbitrsev AS. [Influence repeated stress on immune responciveness and monooxigenase activity of normotensive and hypertensive rats]. ROSSIISKII FIZIOLOGICHESKII ZHURNAL IMENI I.M. SECHENOVA 2008; 94:574-580. [PMID: 18669362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Repeated stress led to antipodal directions in immune system and cytochrome P450 activities of normotensive and hypertensive rats. Enhancement of the Reaction of Delayed Hypersensitivity, suppression of cytochrome P450-mediated monooxigenase activities were observed in Wistar rats. On the contrary, in the NISAG decrease of the Reaction Delayed Hypersensitivity, elevation of cytochrome P450-mediated monooxigenase activities were observed, as comparison with Wistar rats.
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Stoffels K, Overbergh L, Bouillon R, Mathieu C. Immune regulation of 1alpha-hydroxylase in murine peritoneal macrophages: unravelling the IFNgamma pathway. J Steroid Biochem Mol Biol 2007; 103:567-71. [PMID: 17267208 DOI: 10.1016/j.jsbmb.2006.12.091] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The activated form of vitamin D(3), 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), plays an important role in the immune system. Indeed, receptors for 1,25(OH)(2)D(3) are found on most immune cells, and 1alpha-hydroxylase, the enzyme responsible for final activation of vitamin D(3), is expressed by monocytes/macrophages, resulting in secretion of 1,25(OH)(2)D(3) after immune stimulation. We have previously shown that in murine peritoneal macrophages 1alpha-hydroxylase is highly regulated by immune signals such as IFNgamma and LPS. In the present study we made use of two different knock-out mouse models with disruptions in two key transcription factors in the IFNgamma-signalling cascade (STAT1alpha and IRF1), to evaluate their role in the regulation of 1alpha-hydroxylase. This was performed by culturing peritoneal macrophages from these knock-out mice in the presence of IFNgamma and LPS, and evaluating the impact of the absence of the respective transcription factors on 1alpha-hydroxylase mRNA expression by real-time RT-PCR. In addition also the mRNA expression profiles of the essential transcription factors STAT1alpha, IRF1 and C/EBPbeta were investigated. The data confirm a crucial role for STAT1alpha as well as for C/EBPbeta in the regulation of 1alpha-hydroxylase in monocytes.
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Yeung YA, Finney AH, Koyrakh IA, Lebowitz MS, Ghanbari HA, Wands JR, Wittrup KD. Isolation and characterization of human antibodies targeting human aspartyl (asparaginyl) beta-hydroxylase. Hum Antibodies 2007; 16:163-176. [PMID: 18334751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Over-expression of the enzyme human aspartyl (asparaginyl) beta-hydroxylase (HAAH) has been detected in a variety of cancers. It is proposed that upon cellular transformation, HAAH is overexpressed and translocated to the tumor cell surface, rendering it a specific surface antigen for tumor cells. In this work, twelve human single-chain Fv fragments (scFv) against HAAH were isolated from a human non-immune scFv library displayed on the surface of yeast. Five of the twelve were reformatted as human IgG1. Two of the five IgGs, 6-22 and 6-23, showed significant binding to recombinant HAAH in ELISA, tumor cell lines, and tumor tissues. The apparent dissociation constants of 6-22 and 6-23 IgG were 1.0 +/- 0.2 nM and 20 +/- 10 nM respectively. These two antibodies were shown to target different domains of HAAH, with 6-22 targeting the catalytic domain of HAAH and 6-23 targeting the N-terminal non-catalytic domain of HAAH. 6-22 IgG was further characterized, as it had high affinity and targeted the catalytic domain. 6-22 IgG alone does not exhibit significant cytotoxicity toward the tumor cells. However, 6-22 internalizes into tumor cells and can therefore be employed to deliver cytotoxic moieties. A goat anti-human IgG-saporin conjugate was delivered into tumor cells by 6-22 IgG and hence elicited cytotoxicity toward the tumor cells in vitro. These tumor-binding human antibodies can potentially be used in both diagnosis and immunotherapy targeting HAAH-expressing tumor cells.
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Wang J, de la Monte SM, Sabo E, Kethu S, Tavares R, Branda M, Simao L, Wands JR, Resnick MB. Prognostic value of humbug gene overexpression in stage II colon cancer. Hum Pathol 2006; 38:17-25. [PMID: 17020779 DOI: 10.1016/j.humpath.2006.07.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/11/2006] [Accepted: 07/12/2006] [Indexed: 01/03/2023]
Abstract
Overexpression of aspartyl (asparaginyl) beta-hydroxylase (AAH) has been demonstrated in hepatocellular carcinoma, cholangiocarcinoma, and pancreatic carcinoma. AAH has an important role in regulating cell motility and invasiveness. Humbug is a truncated homolog of AAH, with a role in calcium regulation. The present study examines the prognostic use of AAH and humbug gene expression in stage II colon cancer. One hundred thirty cases of TNM stage II colon carcinoma were retrieved from the Rhode Island Hospital pathology archives. Tissue microarrays were immunostained with the FB50 and 15C7 monoclonal antibodies generated to recombinant AAH. However, FB50 also recognizes humbug. In addition, AAH and humbug expression was analyzed in samples of colon cancer and adjacent normal mucosa by real-time quantitative reverse transcriptase-polymerase chain reaction. Humbug (FB50) expression was localized to the tumor cytoplasm, whereas normal colonic epithelium did not exhibit significant immunoreactivity. Humbug staining was detected in 85% of the neoplasms, 23% of which stained strongly. Strong humbug immunoreactivity positively correlated with nuclear grade (P = .006) and inversely with survival (P = .027). In contrast to humbug, AAH (15C7) immunoreactivity was seen in normal and neoplastic epithelium. There was no correlation between AAH immunoreactivity and tumor grade, or survival. Correspondingly, reverse transcriptase-polymerase chain reaction studies demonstrated up-regulation of humbug but not AAH in 95% of colon carcinomas relative to adjacent colon cancer-free mucosa (P < .0001). This study demonstrates that high levels of humbug immunoreactivity in colon carcinomas correlate with histologic grade and tumor behavior, suggesting that humbug can serve as a prognostic biomarker of TNM stage II colon cancers. In addition, molecular studies demonstrated that the increased levels of FB50 detected were due to humbug, as opposed to AAH overexpression.
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Guo J, Nikolic D, Chadwick LR, Pauli GF, van Breemen RB. IDENTIFICATION OF HUMAN HEPATIC CYTOCHROME P450 ENZYMES INVOLVED IN THE METABOLISM OF 8-PRENYLNARINGENIN AND ISOXANTHOHUMOL FROM HOPS (HUMULUS LUPULUS L.). Drug Metab Dispos 2006; 34:1152-9. [PMID: 16611861 DOI: 10.1124/dmd.105.008250] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The female flowers of hops (Humulus lupulus L.) are used in the brewing of beer and are under investigation for use in dietary supplements for the management of menopausal symptoms in women. Hop extracts contain the weakly estrogenic compound isoxanthohumol (IX), proestrogenic xanthohumol, and the potent estrogen 8-prenylnaringenin (8PN). Because IX can be metabolized in the human liver to form 8PN, the specific cytochrome P450 (P450) enzymes responsible for this O-demethylation reaction were identified. In addition, the enzymes that convert IX and 8PN to their most abundant metabolites were identified because these metabolic pathways might also affect the estrogenicity of hop preparations. Specifically, the P450 enzymes that catalyze the oxidation of the prenyl side chains of IX and 8PN into trans- or cis-alcohols were investigated. Human liver microsomes and monoclonal antibodies that inhibit specific P450 enzymes were used in combination with liquid chromatography/mass spectrometry to identify the enzymes responsible for these transformations. CYP2C19 was found to catalyze the formation of both cis- and trans-alcohols of the prenyl side chain of 8PN with K(m) values of 14.8 +/- 3.2 and 16.6 +/- 4.6 microM, respectively. CYP2C8 converted 8PN regioselectively to the trans-alcohol of the prenyl group with a K(m) of 3.7 +/- 0.9 microM. Finally, CYP1A2 was found to catalyze the O-demethylation of IX to generate 8PN, with a K(m) value of 17.8 +/- 3.7 microM. These results suggest that the estrogenicity of hop constituents in vivo will depend in part on metabolic conversion that may show individual variation.
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Uttamsingh V, Lu C, Miwa G, Gan LS. RELATIVE CONTRIBUTIONS OF THE FIVE MAJOR HUMAN CYTOCHROMES P450, 1A2, 2C9, 2C19, 2D6, AND 3A4, TO THE HEPATIC METABOLISM OF THE PROTEASOME INHIBITOR BORTEZOMIB. Drug Metab Dispos 2005; 33:1723-8. [PMID: 16103134 DOI: 10.1124/dmd.105.005710] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
VELCADE (bortezomib, PS-341), reversibly inhibits the 20S proteasome and exhibits cytotoxic and antitumor activities. Pretreatment of cancer cells with bortezomib increases the chemosensitivity of these cells, suggesting that bortezomib may be used in combination chemotherapy. The relative contributions of the five major human cytochromes P450 (P450s), 1A2, 2C9, 2C19, 2D6, and 3A4 (the focus of the present study), to the metabolism of bortezomib are an important aspect of potential drug interactions. Relative activity factor (RAF), chemical inhibition, and immunoinhibition using monoclonal antibodies were three approaches employed to determine the relative contributions of the major human P450s to the net hepatic metabolism of bortezomib. RAFs for the P450 isoform-selective substrates were determined; the ratio of the rate of metabolism of bortezomib with cDNA-expressed P450s versus rate of metabolism with human liver microsomes was normalized with respect to the RAF for each P450 isoform to determine the percentage contributions of the P450s to the net hepatic metabolism of bortezomib. CYP3A4 followed by CYP2C19 were determined to be the major contributors to the metabolism of bortezomib. Chemical inhibition and immunoinhibition confirmed that CYP3A4 and CYP2C19 were the major P450s responsible for the hepatic metabolism of bortezomib. The studies were conducted with 2 muM bortezomib, and the disappearance of bortezomib, rather than appearance of a specific metabolite, was quantified to determine the contributions of the P450s to the overall hepatic metabolism of bortezomib in humans.
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Shinoda M, Tanaka Y, Kuno T, Matsufuji T, Matsufuji S, Murakami Y, Mizutani T. High levels of autoantibodies against drug-metabolizing enzymes in SLA/LP-positive AIH-1 sera. Autoimmunity 2005; 37:473-80. [PMID: 15621574 DOI: 10.1080/08916930400001891] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Autoimmune hepatitis type 1 (AIH-1) is characterized by the detection of smooth muscle autoantibodies, antinuclear antibodies and antineutrophil cytoplasmic autoantibodies, and AIH-2 is characterized by the presence of autoantibodies against LKM, which contain drug-metabolizing enzymes. In this study, we measured the levels of drug-metabolizing enzymes in AIH-1 patients (ANA-positive). We exhaustively investigated the level of autoantibodies against major CYPs and UDP-glucuronosyltransferases of typical phase II drug-metabolizing enzymes, a transporter (MDR1), and NADPH-cytochrome P450 reductase in 4 patients with AIH-1 and 6 controls, as a case report. Two (Patients 3 and 4) of the AIH patients exhibited high levels of autoantibodies, while two (Patients 1 and 2) of the patients and the controls did not. The levels of autoantibodies against CYP2C19, CYP2D6, CYP2E1, UGT1A6 and human liver microsomes in Patients 3 and 4 sera were over 2(3) times the levels in Patient 1, Patient 2 and the control sera. Meanwhile, the levels of autoantibodies against CYP1A2, CYP2A6, CYP2C9, UGT2B7, MDR1 and NADPH-cytochrome P450 reductase were 2-2(2) higher in Patients 3 and 4 than in the other subjects. We found that the pattern of elevation in the Patient 3 serum was not parallel with that in Patient 4. Thus, we found high levels of autoantibodies against drug-metabolizing enzymes in AIH-1 patients.
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Abstract
An in vivo expression technology (IVET) system was previously developed and used to identify Pasteurella multocida genes, which are upregulated during infection of the host. Of the many genes identified, two encoded products which showed similarity to the Haemophilus influenzae lipoproteins, protein D and PCP, which have been shown to stimulate heterologous immunity against infection with H. influenzae. Therefore, the lipoprotein homologues in P. multocida, designated GlpQ and PCP, were investigated. GlpQ and PCP were shown to be lipoproteins by demonstrating that post-translational processing of the proteins was inhibited by globomycin. The P. multocida GlpQ homologue showed glycerophosphodiester phosphodiesterase enzyme activity, indicating that it is a functional homologue of other characterized GlpQ enzymes. Using surface immunoprecipitation, PCP was found to be surface exposed, but GlpQ was not. Non-lipidated forms of GlpQ and PCP were expressed and purified from Escherichia coli and used to vaccinate mice. However, mice were not protected from challenge with live P. multocida. The lipoproteins were then expressed in E. coli in the lipidated form and used to vaccinate mice and chickens. Protection against challenge with live P. multocida was not observed.
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Canto-Canché BB, Meijer AH, Collu G, Verpoorte R, Loyola-Vargas VM. Characterization of a polyclonal antiserum against the monoterpene monooxygenase, geraniol 10-hydroxylase from Catharanthus roseus. JOURNAL OF PLANT PHYSIOLOGY 2005; 162:393-402. [PMID: 15900881 DOI: 10.1016/j.jplph.2004.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Geraniol 10-hydroxylase (G10H) is a P450 containing enzyme which is the first committed step in the biosynthesis of monoterpene indole alkaloids (MIAs), including the Catharanthus roseus-anticancer drugs vinblastine and vincristine. It is thought that G10H has a regulatory role in MIA production. In the present paper, we report the characterization of a polyclonal serum raised against the purified G10H polypeptide. Anti-G10H IgG was able to inhibit the G10H activity and also recognized the G10H polypeptide from C. roseus and other plants producing MIAs. These results establish the usefulness of this antiserum as a biochemical tool for the study of G10H regulation.
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Hirani VN, Raucy JL, Lasker JM. Conversion of the HIV protease inhibitor nelfinavir to a bioactive metabolite by human liver CYP2C19. Drug Metab Dispos 2004; 32:1462-7. [PMID: 15448116 DOI: 10.1124/dmd.104.001743] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Antiretroviral therapy for human immunodeficiency virus (HIV) infection includes treatment with both reverse transcriptase inhibitors and protease inhibitors, which markedly suppress viral replication and circulating HIV RNA levels. Cytochrome P450 (P450) enzymes in human liver, chiefly CYP3A4, play a pivotal role in protease inhibitor biotransformation, converting these agents to largely inactive metabolites. However, the protease inhibitor nelfinavir (Viracept) is metabolized mainly to nelfinavir hydroxy-t-butylamide (M8), which exhibits potent antiviral activity, and to other minor products (termed M1 and M3) that are inactive. Since indirect evidence suggests that CYP2C19 underlies M8 formation, we examined the role of this inducible, polymorphic P450 enzyme in nelfinavir t-butylamide hydroxylation by human liver. Rates of microsomal M8 formation were 50.6 +/- 28.3 pmol of product formed/min/nmol P450 (n = 5 subjects), whereas kinetic analysis of the reaction revealed a KM of 21.6 microM and a Vmax of 24.6 pmol/min/nmol P450. In reconstituted systems, CYP2C19 catalyzed nelfinavir t-butylamide hydroxylation at a turnover rate of 2.2 min(-1), whereas CYP2C9, CYP2C8, and CYP3A4 were inactive toward nelfinavir. Polyclonal anti-CYP2C9 (cross-reactive with CYP2C19) and monoclonal anti-CYP2C19 completely inhibited microsomal M8 production, whereas monoclonal CYP2C9 and polyclonal CYP3A4 antibodies were without effect. Similarly, the CYP2C19 substrate omeprazole strongly inhibited (75%) hepatic nelfinavir t-butylamide hydroxylation at a concentration of only 12.5 microM. Our study shows that CYP2C19 underlies formation in human liver of M8, a bioactive nelfinavir metabolite. The inducibility of CYP2C19 by agents (e.g., rifampicin) often taken concurrently with nelfinavir, together with this P450's known polymorphic nature, may thus be important determinants of nelfinavir's antiviral potency.
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Humphreys JM, Chapple C. Immunodetection and quantification of cytochromes P450 using epitope tagging: immunological, spectroscopic, and kinetic analysis of cinnamate 4-hydroxylase. J Immunol Methods 2004; 292:97-107. [PMID: 15350515 DOI: 10.1016/j.jim.2004.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2003] [Revised: 06/02/2004] [Accepted: 06/08/2004] [Indexed: 10/26/2022]
Abstract
Cytochrome P450-dependent monooxygenases (P450s) are integral membrane proteins typically expressed at low levels both in vivo and by heterologous expression systems, often making quantification of these enzymes challenging. Since the time of their discovery, P450s have typically been quantified by their carbon monoxide (CO) difference spectra. Although this technique is reliable, it requires quantities of enzyme that are sometimes difficult to obtain, and spectroscopic instruments and expertise frequently unavailable in laboratories whose primary focus is genetics or molecular biology. We have developed a method for quantifying recombinant FLAG epitope-tagged proteins using fluorescence detection of a chromophore-labeled anti-FLAG monoclonal antibody and well-established immunoblot technology. The utility of this technique was tested using cinnamate 4-hydroxylase (C4H), one of the best-studied plant P450s. No substantial differences in the stability or kinetic properties were observed between the native and FLAG-tagged enzymes. Immunochemical quantification of epitope-tagged C4H reported slightly lower P450 concentrations than conventional methods but has a limit of quantification 400-fold lower than carbon monoxide difference spectroscopy.
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Dalekos GN, Obermayer-Straub P, Bartels M, Maeda T, Kayser A, Braun S, Loges S, Schmidt E, Gershwin ME, Manns MP. Cytochrome P450 2A6: a new hepatic autoantigen in patients with chronic hepatitis C virus infection. J Hepatol 2003; 39:800-6. [PMID: 14568264 DOI: 10.1016/s0168-8278(03)00356-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND/AIMS Cytochromes P4502A6 (CYP2A6) and P4501A2 (CYP1A2) were described as hepatic autoantigens in the autoimmune polyglandular syndrome type-1 (APS-1). We evaluated the significance of anti-CYP2A6 and anti-CYP1A2 in several hepatic diseases in the absence of APS-1. METHODS A radioligand assay (RLA) based on immunoprecipitation of [(35)S]-methionine-labeled CYP2A6 and CYP1A2 was used. Four hundred and thirty subjects with chronic viral hepatitis (n=185), autoimmune liver diseases (n=181), autoimmune rheumatic diseases (ARD, n=31) and healthy (n=33) were tested. RESULTS Seven out of 366 patients with liver diseases were anti-CYP2A6 positive. Neither healthy nor ARD patients showed anti-CYP2A6. One out of 181 patients with autoimmune liver diseases tested anti-CYP2A6 positive. A significantly higher prevalence of anti-CYP2A6 (P<0.05) was detected with six out of seven patients positive in the viral hepatitis group. The latter were infected by flaviviruses (1 HGV/GBVC, 5 HCV). 4/5 HCV/anti-CYP2A6 positive sera were positive for anti-LKM-1 by immunofluorescence and for anti-CYP2D6 by RLA. None of the 430 sera recognized CYP1A2. CONCLUSIONS For the first time CYP2A6 is reported as a hepatic autoantigen in patients with viral hepatitis caused by flaviviruses and in particular in HCV/anti-LKM-1 positive patients. Multicenter studies are needed in order to investigate the clinical importance of this novel finding. This study further supports that anti-CYP2A6 in the absence of flavivirus is rather limited to APS-1.
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Kita T, Sakaeda T, Baba T, Aoyama N, Kakumoto M, Kurimoto Y, Kawahara Y, Okamura N, Kirita S, Kasuga M, Okumura K. Different contribution of CYP2C19 in the in vitro metabolism of three proton pump inhibitors. Biol Pharm Bull 2003; 26:386-90. [PMID: 12612455 DOI: 10.1248/bpb.26.386] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A series of clinical studies on the cytochrome P450 2C19 (CYP2C19) genotype and the pharmacokinetics and pharmacodynamics of three proton pump inhibitors (PPIs), omeprazole, lansoprazole and rabeprazole, have been conducted to establish the individualized pharmacotherapy based on the CYP2C19 genotyping, and in the present study, the CYP2C19 genotype-dependency was more pronounced for omeprazole than the other two. Herein, to validate further the difference among 3 PPIs in CYP2C19 genotype-dependency on the phenotype, a comparative in vitro study was conducted using the human liver microsomes and newly developed anti-human CYP antibodies. The residual concentrations of omeprazole and lansoprazole in 5 lots of human liver microsomes were dependent on the CYP2C19 activities, however, for rabeprazole, there was no correlation. The hydroxylation of omeprazole was more inhibited by anti-CYP2C19 antibody than lansoprazole, whereas anti-CYP3A4 antibody showed similar inhibition. In conclusion, the relative contribution of CYP2C19 on total metabolism of 3 PPIs elucidated herein coincided with the CYP2C19 genotype-dependent pharmacokinetics.
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Malykh YN, King TP, Logan E, Kelly D, Schauer R, Shaw L. Regulation of N-glycolylneuraminic acid biosynthesis in developing pig small intestine. Biochem J 2003; 370:601-7. [PMID: 12444926 PMCID: PMC1223197 DOI: 10.1042/bj20021049] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2002] [Revised: 11/13/2002] [Accepted: 11/22/2002] [Indexed: 11/17/2022]
Abstract
N -Glycolylneuraminic acid (Neu5Gc), an abundant sialic acid in animal glycoconjugates, is formed by the enzyme CMP-N-acetylneuraminic acid (CMP-Neu5Ac) hydroxylase. The amount of Neu5Gc relative to other sialic acids is highly dependent on the species, tissue and developmental stage. Although the activity of the hydroxylase is a key factor in controlling Neu5Gc incorporation in adult animals, little is known about the regulation of hydroxylase expression and the role of this enzyme in determining changes in Neu5Gc during development. Using pig small intestine as a model system, the appearance of total sialic acid and the regulation of Neu5Gc biosynthesis during development were studied in various regions of this tissue. The amount of total sialic acid and Neu5Gc declined markedly in 2 weeks after birth. Although in subsequent developmental phases there were no positional differences in total sialic acid, a significant proximal-to-distal increase in Neu5Gc was detected. In all cases, a good correlation between the amount of Neu5Gc, the activity of the hydroxylase and the level of hydroxylase mRNA was observed. However, Western-blot analysis revealed considerable accumulation of less active enzyme in the post partum period, which persisted until adulthood. No evidence for cytosolic factors influencing the hydroxylase activity or for the formation of truncated enzyme was found, raising the possibility that other regulatory mechanisms are involved. The relevance of these results in the formation of Neu5Gc as a receptor for certain pig enteric pathogens is also discussed.
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Wang H, Marjomäki V, Ovod V, Kulomaa MS. Subcellular localization of pentachlorophenol 4-monooxygenase in Sphingobium chlorophenolicum ATCC 39723. Biochem Biophys Res Commun 2002; 299:703-9. [PMID: 12470635 DOI: 10.1016/s0006-291x(02)02719-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the subcellular localization of pentachlorophenol 4-monooxygenase (PCP4MO) in Sphingobium chlorophenolicum ATCC 39723 during induction by pentachlorophenol (PCP). Using a monoclonal antibody CL6 specific to the native and recombinant PCP4MO, the enzyme was primarily found soluble as determined by immunoblot and ELISA analyses of cellular fractions. However, the enzyme was observed both in the soluble and membrane-bound forms during induction for 2-4 h, suggesting its translocation out from the cytoplasm. Electron microscopy confirmed that PCP4MO was predominantly present in the cytoplasm at 1 h, whereas at 4 h significant amount was detected also in the membrane and periplasm. After 6 h, the majority of PCP4MO was in the periplasm and only small amount was bound to the inner membrane or present in the cytoplasm. The results indicate that after biosynthesis PCP4MO in S. chlorophenolicum is exported via the inner membrane to the final location in the periplasm.
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Palumbo KS, Wands JR, Safran H, King T, Carlson RI, de la Monte SM. Human aspartyl (asparaginyl) beta-hydroxylase monoclonal antibodies: potential biomarkers for pancreatic carcinoma. Pancreas 2002; 25:39-44. [PMID: 12131769 DOI: 10.1097/00006676-200207000-00010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Pancreatic adenocarcinoma is among the top 10 leading causes of death due to cancer in the United States. The lack of reliable and sensitive biomarkers for this disease makes it difficult to render an early diagnosis. AIMS To evaluate carcinoma-associated monoclonal antibodies (MoAbs), including AF-20, SF-25, and FB-50, for their binding specificity to pancreatic adenocarcinoma relative to normal pancreatic tissue. In addition, binding of the Th9 MoAb to human Reg 1 protein was studied because of its potential role in cell growth. METHODOLOGY Adjacent histologic sections were immunostained with each of the MoAbs and graded on a scale of 0 to 4+, corresponding to the relative distribution and intensity of immunoreactivity within the tumor and normal adjacent tissue. RESULTS Intense levels (grade 3 or 4) of FB50 immunoreactivity were detected in 19 of 19 tumors but not in normal adjacent pancreatic tissue. In addition, increased levels of FB50 immunoreactivity were detected in at least 75% of the tumor cells in 18 of the 19 cases. SF-25 immunoreactivity similarly distinguished pancreatic adenocarcinoma from normal pancreas in 14 of 19 cases. In contrast, AF20 immunoreactivity was detected in 6 of 19 pancreatic adenocarcinomas, and for the most part, the labeling was focal and of a low level. TH9 immunoreactivity was detected in 5 of 19 tumors but also in normal as well as inflamed adjacent pancreatic tissue. CONCLUSION These results suggest that the FB50 and SF25 MoAbs represent excellent potential biomarkers of pancreatic adenocarcinoma and could be configured in an immunoassay for detecting pancreatic adenocarcinoma cells in biologic fluids.
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Lytton SD, Berg U, Nemeth A, Ingelman-Sundberg M. Autoantibodies against cytochrome P450s in sera of children treated with immunosuppressive drugs. Clin Exp Immunol 2002; 127:293-302. [PMID: 11876753 PMCID: PMC1906342 DOI: 10.1046/j.1365-2249.2002.01754.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Treatment with the immunosuppressive drugs cyclosporin and tacrolimus, the mainstays of anti-graft rejection and autoimmune disease therapy, is limited by their hepato- and nephrotoxicity. The metabolic conversion of these compounds to more easily excretable products is catalysed mainly by hepatic cytochrome P4503A4 (CYP3A4) but also involves extrahepatic CYP3A5 and other P450 forms. We set out to study whether or not exposure to cyclosporin and FK506 in children undergoing organ transplantation leads to formation of autoantibodies against P450s. Immunoblotting analysis revealed anti-CYP reactivity in 16% of children on CyA for anti-graft rejection or treatment of nephrosis (n = 67), 31% of kidney transplant patients switched from CyA to FK506 (n = 16), and 21% of kidney and or liver transplant patients on FK506 (n = 14). In contrast, the frequency of reactive immunoblots was only 8.5% among the normal paediatric controls (n = 25) and 7% among adult kidney transplant patients on CyA or FK506 (n = 30). The CYP2C9+ sera were able to immunoprecipitate in vitro translated CYP2C9 and the immunoblot reactivity showed striking correlation to peaks in the age at onset of drug exposure. Sera were isoform selective as evidenced from Western blotting using human liver microsomes and heterologously expressed human P450s. These findings suggest that anti-cytochrome P450 autoantibodies, identified on the basis of their specific binding in immunoblots, are significantly increased among children on immunosuppressive drugs and in some cases are associated with drug toxicity and organ rejection.
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Dalekos GN, Makri E, Loges S, Obermayer-Straub P, Zachou K, Tsikrikas T, Schmidt E, Papadamou G, Manns MP. Increased incidence of anti-LKM autoantibodies in a consecutive cohort of hepatitis C patients from central Greece. Eur J Gastroenterol Hepatol 2002; 14:35-42. [PMID: 11782573 DOI: 10.1097/00042737-200201000-00007] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVES In Greece, there are insufficient data regarding the presence of non-organ and liver-related autoantibodies in hepatitis C patients. This study in a consecutive cohort of 39 such patients from central Greece investigates (1) the prevalence of non-organ and liver-related autoantibodies, and (2) the reactivity of anti-liver-kidney microsomal type 1 antibodies (in the case of positivity with at least one of the methods used) against their molecularly defined antigens. DESIGN All serum samples were tested by standard and molecular assays for the presence of anti-nuclear antibodies, smooth muscle antibodies, anti-liver-kidney microsomal type 1 antibodies, antibodies against parietal cells, anti-CYP2A6, anti-CYP1A2 and anti-CYP2D6 autoantibodies. METHODS Indirect immunofluorescence, competitive enzyme-linked immunosorbent assays, immunoblotting and novel radioligand assays based on immunoprecipitation of [35S]-methionine labelled recombinant CYP2A6, CYP1A2 and CYP2D6 His-taq fusion proteins produced by in vitro transcription/translation were used. RESULTS Seven out of 39 patients (17.9%) tested positive for smooth muscle antibodies, 2/39 (5.1%) tested positive for anti-nuclear antibodies, 1/39 (2.5%) tested positive for parietal cell antibodies, and 4/39 (10.3%) were found to be anti-liver-kidney microsomal positive (with at least one of the methods used). All sera were negative for anti-CYP2A6 and anti-CYP1A2 autoantibodies. Three out of four anti-liver-kidney microsomal positive samples had the typical liver-kidney microsomal staining pattern shown by indirect immunofluorescence. However, none tested positive for anti-CYP2D6 autoantibodies using the competitive CYP2D6 enzyme-linked immunosorbent assay, the specific CYP2D6 radioligand assay, and western blot using either human microsomes or recombinant CYP2D6. The fourth patient tested negative for anti-liver-kidney autoantibodies by either indirect immunofluorescence or the competitive enzyme-linked immunosorbent assay, but was repeatedly positive for anti-CYP2D6 autoantibodies by the sensitive and specific radioligand assay. Western blot experiments using human microsomes in this patient serum revealed two bands of 50 kDa and 55 kDa that documented as anti-CYP2D6 and anti-uridine triphosphate glucuronosyltransferase autoantibodies when recombinant CYP2D6 and recombinant uridine triphosphate glucuronosyltransferase autoantigens were used for immunoblot, respectively. CONCLUSIONS A relatively high incidence of anti-liver-kidney microsomal autoantibodies (10.3%) was found in a consecutive sample of Greek patients with hepatitis C. The expanded panel of assays, however, failed to document CYP2D6 as the target autoantigen of anti-liver-kidney microsomal autoantibodies in most patients. We report for the first time the detection of parietal cell antibodies and both anti-CYP2D6 (anti-liver-kidney microsomal type 1) and anti-uridine triphosphate glucuronosyltransferase (anti-liver-kidney microsomal type 3) autoantibodies in patients who were hepatitis C positive/hepatitis D negative. Further studies are needed to confirm our findings and to determine whether these preliminary results have a clinical importance or not.
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Krausz KW, Goldfarb I, Buters JT, Yang TJ, Gonzalez FJ, Gelboin HV. Monoclonal antibodies specific and inhibitory to human cytochromes P450 2C8, 2C9, and 2C19. Drug Metab Dispos 2001; 29:1410-23. [PMID: 11602516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Hybridomas were isolated that produce 13 monoclonal antibodies (mAbs) that are specific and highly inhibitory to members of the human P450 2C subfamily, 2C8, 2C9, 2C9*2, and 2C19. Many of the mAbs to P450 2C8, 2C9, and 2C19 are specific and exhibit potent inhibitory activity (85-95%). mAb 281-1-1 specifically binds, immunoblots, and strongly inhibits the activity of P450 2C8. mAb 763-15-5 specifically binds and strongly inhibits the activity of P450 2C9. mAb 1-7-4-8 specifically binds and strongly inhibits the activity of P450 2C19. The other mAbs bind and inhibit sets and subsets of the P450 2C family. The single and the combinatorial use of the mAbs can "reaction phenotype", i.e., determine the metabolic contribution and interindividual variation of a P450 isoform for the metabolism of a drug or nondrug xenobiotic in human liver microsomes. The utility of the mAb-based analytic system was examined with the model substrates Taxol (paclitaxel), diazepam, tolbutamide, diclofenac, mephenytoin, and imipramine. The mAb system can identify drugs metabolized by a common P450 or several P450s and polymorphic P450s. The mAb system identifies drugs or drug metabolic pathways that are catalyzed by a single P450 and thus may be used for in vivo phenotyping. The mAb system can identify whether a particular drug is metabolized by a single P450 that may exhibit polymorphic expression in humans. The mAb system offers large potential for studies of cytochrome P450 function useful in drug discovery and reduces the possibility of adverse drug reactions due to polymorphisms and drug interactions.
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