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1.
Bull Exp Biol Med ; 170(2): 241-245, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33263849

RESUMO

The proportion of CD44+CD24low cancer stem cells (CSC) was determined in cervical scrapings of 41 patients with squamous cell carcinoma of the uterine cervix before treatment and after irradiation in a total focal dose of 10 Gy. The relationship of quantitative changes in the CSC population with such parameters of papillomavirus infection as genotype, viral load, and physical status of HPV DNA (the absence or presence of HPV DNA integration into the cell genome and the degree of integration) was studied. Single- and multi-factor analysis revealed 2 independent indicators affecting the radiation response of CSC: initial number of these cells before treatment and physical status of HPV DNA. The increase in the CSC proportion after radiation exposure was observed 4.5-fold more often in patients with an initially low proportion of CSC (<3%) than that in other patients (p=0.001). The CSC proportion increased by on average 3% after irradiation in patients with complete integration of HPV 16/18 DNA and decreased by 3.8 % in patients with partial integration or no integration (p=0.03).


Assuntos
Carcinoma de Células Escamosas/radioterapia , Células-Tronco Neoplásicas/efeitos da radiação , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Alphapapillomavirus , Antígeno CD24/biossíntese , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia , Colo do Útero/virologia , DNA Viral/metabolismo , Feminino , Genótipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Receptores de Hialuronatos/biossíntese , Pessoa de Meia-Idade , Biologia Molecular , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Tolerância a Radiação , Resultado do Tratamento , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Carga Viral , Integração Viral , Adulto Jovem
2.
Bull Exp Biol Med ; 168(1): 87-91, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31768781

RESUMO

The presence of virus DNA integration into the cell genome was studied for 47 primary HPV16-positive patients with morphologically verified stage III cervical cancer. By using ROC analysis, the patients were divided into two groups: with and without HPV DNA integration into the host cell genome. The differences between the groups by the histological type, degree of tumor differentiation, and primary response to therapy were statistically insignificant. Virus DNA integration more than 7-fold reduced 5-year relapse-free survival and 1.7-fold reduced overall survival rate in comparison with patients without HPV DNA integration (p=0.0002 and p=0.05, respectively). The relative risk of adverse outcome of the disease in patients with the presence of HPV16 DNA integration increases by 4 times over a period of less than 3 years (р=0.0006) at high AUC level. The probability of earlier progression of the disease in patients with of HPV DNA integration calculated according to the Cox proportional hazards model was 85.5% (hazard ratio 5.96; p=0.002). Thus, the results suggest that the presence of HPV16 DNA integration into the cell genome is an independent factor in predicting clinical outcome of advanced cervical cancer and can serve as an effective criterion for the individual choice of treatment tactics for the patients.


Assuntos
DNA Viral/genética , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/patologia , Feminino , Humanos , Recidiva Local de Neoplasia/genética , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Integração Viral/genética , Integração Viral/fisiologia
3.
Prikl Biokhim Mikrobiol ; 51(4): 417-23, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26353407

RESUMO

Clove bud essential oil, extracts from ginger, pimento and black pepper, or ascorbyl palmytate were studied as natural antioxidants for the inhibition of autooxidation of polyunsaturated fatty acids in linseed oil. Different methods were used to estimate antioxidant efficiency. These methods are based on the following parameters: peroxide values; peroxide concentration; content of degradation products of unsaturated fatty acid peroxides, which acted with thiobarbituric acid; diene conjugate content; the content of volatile compounds that formed as products of unsaturated fatty acid peroxide degradation; and the composition of methyl esters of fatty acids in samples of oxidized linseed oil.


Assuntos
Antioxidantes/química , Óleo de Semente do Linho/química , Óleos Voláteis/farmacologia , Syzygium/química , Zingiber officinale/química , Óleos Voláteis/química , Oxirredução/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia
4.
Vopr Onkol ; 60(3): 348-51, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25033689

RESUMO

There was performed a comparative analysis of quantitative load and physical status of human papillomavirus (HPV) type 16 in groups of patients with cervical intraepithelial neoplasia (CIN)--25 people and cervical cancer (CC)--85 people. According to the analysis there were selected criteria appropriate to a combination of adverse factors that characterized HPV- infection and at the same time estimated both quantitative load and physical status of the virus: high viral load (> 6,5 lg copies of HPV DNA per 100000 cells) in episomal form or low load (< 6,5 lg copies of HPV DNA per 100000 cells) in integrated form of the virus. According to calculations a relative chance of appearing of CC in CIN patients with unfavorable combination of factors was 7,5 times higher than in other patients.


Assuntos
Transformação Celular Neoplásica , Colo do Útero/patologia , Colo do Útero/virologia , Papillomavirus Humano 16/isolamento & purificação , Infecções por Papillomavirus/complicações , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , DNA Viral/isolamento & purificação , Feminino , Papillomavirus Humano 16/genética , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Infecções por Papillomavirus/virologia , Prognóstico , Risco , Neoplasias do Colo do Útero/patologia , Carga Viral
5.
Vopr Onkol ; 59(6): 756-60, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24624787

RESUMO

For the 83 patients with HPV 16-cancer of the cervix (cervical cancer) I-III stages it was performed a comparative analysis of primary tumor response to therapy, the clinical outcome of the disease for 3-5 years after radical treatment and an evaluation of the possible contribution in these rates of the physical status of the virus. It was shown that total tumors regression in the early stages of the observation predominate in patients with "high-integrated" virus DNA (the degree of integration > 50%) of compared with a group of patients with episomal and "low-integrated" form of the virus, but in a distant periods (3-5 years) in the first group predominate an adverse outcome of disease. This pattern is true for tumors of stage I-III, and for less common--I-II stages. It is assumed that the integration of HPV16 DNA into the cellular genome may serve as an independent predictor of clinical outcome of cervical cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Genoma Humano , Papillomavirus Humano 16/patogenicidade , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Pesquisa Comparativa da Efetividade , DNA Viral/análise , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Papillomavirus Humano 16/genética , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Infecções por Papillomavirus/virologia , Compostos de Platina/administração & dosagem , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Prognóstico , Resultado do Tratamento , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia
6.
Vopr Onkol ; 56(2): 185-90, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20552895

RESUMO

Real-time polymerase chain reaction procedure was used to evaluate bioptic tumor samples from patients suffering cervical carcinoma (CC) stages I-IV. Out of 110 patients, high-risk human papillomavirus (HPV) infection was identified in 98 (89.1%), HPV type 16--63, HPV type 18--10 and HPV type 45--5. One of genotypes 31.33, 35, 39, 52, 58, 59 was established in 8 and a combination of several genotypes of the virus--12 patients. Frequency of remission in CC patients associated with HPV type 16 who had survived 3 years was significantly higher than in the same category associated with HPV type 18 (p=0.03). Relapse frequency and mortality rates in patients with tumors associated with one of viruses 31.33, 35, 39, 52, 58 or 59 were higher as compared with HPV type 16--associated cases 2 years (p=0.03) or 3 years on (p=0.11), respectively. A similar trend was established for squamous-cell tumors stages 1 and 2 (p=0.07) (p=0.12), respectively. No difference was observed in efficacy of therapy for infection with one or a combination of several genotypes of high-risk HPV. Hence, the genotype of virus is believed to be a factor of prognosis in CC early cancers. However, a definitive conclusion cannot be reached until results of a larger body of evidence and longer follow-up are available.


Assuntos
Alphapapillomavirus/isolamento & purificação , Infecções por Papillomavirus/complicações , Infecções Tumorais por Vírus/complicações , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Alphapapillomavirus/genética , DNA Viral/isolamento & purificação , Feminino , Genótipo , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco , Infecções Tumorais por Vírus/virologia
7.
Biochim Biophys Acta ; 1478(1): 69-77, 2000 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-10719176

RESUMO

Intrinsic lysozyme-like activity was demonstrated for destabilase from the medicinal leech supported by (1) high specific lysozyme activity of the highly purified destabilase, (2) specific inhibition of the lysozyme-like activity by anti-destabilase antibodies, and (3) appreciable lysozyme-like activity in insect cells infected with recombinant baculoviruses carrying cDNAs encoding different isoforms of destabilase. Several isoforms of destabilase constitute a protein family at least two members of which are characterized by lysozyme activity. The corresponding gene family implies an ancient evolutionary history of the genes although the function(s) of various lysozymes in the leech remains unclear. Differences in primary structures of the destabilase family members and members of known lysozyme families allow one to assign the former to a new family of lysozymes. New proteins homologous to destabilase were recently described for Caenorhabditis elegans and bivalve mollusks suggesting that the new lysozyme family can be widely distributed among invertebrates. It remains to be investigated whether the two enzymatic activities (isopeptidase and lysozyme-like) are attributes of one and the same protein.


Assuntos
Endopeptidases/metabolismo , Sanguessugas/enzimologia , Muramidase/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Baculoviridae/genética , Carbono-Nitrogênio Liases/metabolismo , Linhagem Celular , DNA Complementar/genética , Endopeptidases/genética , Endopeptidases/imunologia , Escherichia coli/metabolismo , Expressão Gênica , Isoenzimas/química , Dados de Sequência Molecular , Muramidase/química , Muramidase/genética , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Especificidade por Substrato
8.
FEBS Lett ; 413(2): 231-5, 1997 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-9280287

RESUMO

Both free and hidden natural antibodies to DNA or cardiolipin were obtained from immunoglobulins of a normal donor. The free antibodies reacting with DNA or cardiolipin were isolated by means of affinity chromatography. Antibodies occurring in an hidden state were disengaged from the depleted immunoglobulins by ion-exchange chromatography and were then affinity-isolated on DNA or cardiolipin sorbents. We used flow cytometry to study the ability of free and hidden antibodies to bind to rat thymocytes. Simultaneously, plasma membrane integrity was tested by propidium iodide (PI) exclusion. The hidden antibodies reacted with 65.2 +/- 10.9% of the thymocytes and caused a fast plasma membrane disruption. Cells (28.7 +/- 7.1%) were stained with PI after incubation with the hidden antibodies for 1 h. The free antibodies bound to a very small fraction of the thymocytes and did not evoke death as compared to control without antibodies. The possible reason for the observed effects is difference in reactivity of the free and hidden antibodies to phospholipids. While free antibodies reacted preferentially with phosphotidylcholine, hidden antibodies reacted with cardiolipin and phosphotidylserine.


Assuntos
Anticorpos/sangue , Cardiolipinas/imunologia , DNA/imunologia , Linfócitos T/imunologia , Animais , Anticorpos/isolamento & purificação , Especificidade de Anticorpos , Morte Celular/imunologia , Células Cultivadas , Fragmentação do DNA , Citometria de Fluxo/métodos , Humanos , Imunidade Inata/imunologia , Fosfolipídeos/imunologia , Ratos , Timo/imunologia
11.
Biokhimiia ; 60(5): 783-90, 1995 May.
Artigo em Russo | MEDLINE | ID: mdl-7662803

RESUMO

A simple method for detecting pathogenic microorganisms in clinical samples has been developed. This method is based on identification of specific nucleotide sequences by Pt[(dien)Cl] Cl-labelled DNA probes and simultaneous immunochemical control of total DNA content in each clinical sample. Such control is provided by a simple semiquantitative enzyme-linked immunoassay using antibodies to denatured DNA; its implementation requires the same procedures, materials and solutions used in the hybridization analysis. The information about the DNA content in the sample is necessary for adequate interpretation of results of hybridization analysis. Pt[(dien)Cl]Cl for the probe and affinity antibodies to DNA-Pt[(dien)Cl] Cl and rabbit immunoglobulin antibodies conjugated to phosphatase for DNA hybrid detection were used. The results of hybridization analysis show a good correlation with those of the PCR-test. The method is simple, relatively inexpensive and fit for population monitoring.


Assuntos
Chlamydia trachomatis/isolamento & purificação , Cisplatino/análogos & derivados , Sondas de DNA , Ureaplasma urealyticum/isolamento & purificação , Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/genética , Cisplatino/química , DNA Bacteriano/isolamento & purificação , Feminino , Humanos , Masculino , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Infecções por Ureaplasma/diagnóstico , Ureaplasma urealyticum/genética
12.
Eur J Biochem ; 228(3): 616-24, 1995 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-7737155

RESUMO

Modifications of natural DNA and synthetic double-stranded oligodeoxyribonucleotides by cis-diamminedichloro-trans-dihydroxyplatinum(IV) (oxoplatin) were studied by means of ELISA, Maxam-Gilbert footprinting techniques, HPLC of enzymically digested DNA, and transcription assay. It was found that oxoplatin can bind DNA directly without addition of a reducing agent. In addition, the antibodies elicited against DNA modified by cisplatin were not competitively inhibited by DNA modified by oxoplatin. However, DNA containing the adducts of oxoplatin became a strong inhibitor of these antibodies, if it was subsequently treated with ascorbic acid, which is a reducing agent. These results were interpreted to mean that oxoplatin can form DNA adducts containing the platinum moiety in the quadrivalent state. The direct irreversible binding of the platinum(IV) drug is, however, slow as compared to the reaction of its platinum(II) counterpart. It was also found that oxoplatin preferentially binds to guanine residues and can form DNA intrastrand and interstrand cross-links containing platinum(IV). The DNA adducts containing platinum(IV) can inhibit in vitro transcription by a prokaryotic DNA-dependent RNA polymerase. We find that the platinum(IV) complex binds to DNA at similar sites as its platinum(II) counterpart. On the other hand, the DNA adducts containing the platinum(II) or platinum(IV) analogues differ in the number of ligands and the formal charge on their platinum center. We suggest that these differences could be responsible for distinct conformational features and stability of DNA modified by platinum(II) or platinum(IV) complexes.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/análogos & derivados , DNA/efeitos dos fármacos , Animais , Sequência de Bases , Bovinos , Cromatografia Líquida de Alta Pressão , Cisplatino/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , DNA/metabolismo , Imunoquímica , Dados de Sequência Molecular , Transcrição Gênica
13.
Mol Biol (Mosk) ; 28(4): 768-77, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7990804

RESUMO

A very strong electroosmotic counterflow was produced on nitrocellulose membranes during isotachophoresis in a system of 0.06 M Tris-HCl (pH 6.7) as the leading electrolyte and 0.012 M Tris-beta-alanine (pII 8.6) as the terminating one. This counterflow was equal in rate and opposite in direction to the migration of the Cl-/beta-alanine boundary. The rate of counterflow was much higher than the rate of migration of any organic anions, including different proteins. Double-stranded and single-stranded DNA or its adducts were fixed on the nitrocellulose membrane, and the membrane was blocked with unrelated proteins. DNA-binding proteins, namely antibodies to DNA, followed by peroxidase-conjugated anti-IgG, were introduced into the counterflow, which transferred them one after another to the DNA spots. Thus, sequential binding and washing was performed automatically. In this way, antibodies were detected to ds- and ss-DNA, to BrdU-DNA, to Z-DNA, to biotinylated DNA and DNA modified with trans-Pt, as well as development of biotinylated DNA dots by steptavidin-peroxidase.


Assuntos
Anticorpos Antinucleares , Adutos de DNA , Proteínas de Ligação a DNA/análise , DNA/imunologia , Western Blotting/instrumentação , Colódio , Contraimunoeletroforese , Eletroforese/métodos
14.
Immunol Lett ; 40(2): 133-8, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7522218

RESUMO

Electrochromatography (ECHR) exploits a very high electro-osmotic counterflow developed in porous membranes at discontinuous electrophoresis. This counterflow exceeds considerably the anodic migration of any negatively charged protein and is used as a 'conveyer belt' for sequential transfer of immunoreagents to the specific adsorbents (antigens or antibodies) fixed on the nitrocellulose membrane. This approach was applied for simultaneous detection of two antigens (alpha-fetoprotein and carcino-embryonic antigen) in one sample, for determination of subfractions of alpha-fetoprotein, different in their epitope specificity, and for detection of L chains with certain idiotype on the background of heterogeneous L fraction. ECHR was used also for the partition of different antibodies to DNA adducts, demonstrating the possibility of applying this method to the study of DNA-binding proteins.


Assuntos
Antígeno Carcinoembrionário/análise , Cromatografia de Afinidade/métodos , Membranas Artificiais , alfa-Fetoproteínas/análise , Anticorpos Monoclonais , Automação , Antígeno Carcinoembrionário/imunologia , DNA/imunologia , Dano ao DNA , Proteínas de Ligação a DNA/análise , Eletroquímica , Epitopos/análise , Epitopos/imunologia , Humanos , alfa-Fetoproteínas/imunologia
15.
Bioorg Khim ; 20(1): 14-20, 1994 Jan.
Artigo em Russo | MEDLINE | ID: mdl-8161359

RESUMO

Monofunctional platinum compound [Pt(dien)Cl] Cl and high-affinity antibodies against DNA-[Pt(dien)Cl]Cl were suggested for non-radioactive hybridisation analysis of DNA. The simple labelling procedure was based on mixing the reagents followed by the incubation for 2 h at 60 degrees C. The sensitivity and specificity of the technique were sufficient to detect 10 fg DNA in dot-hybridisation without cross-reaction with 10-fold excess of a heterologous DNA. This technique permits genome libraries screening.


Assuntos
Cisplatino/análogos & derivados , DNA/química , Compostos Organoplatínicos/química , Análise de Sequência de DNA , Afinidade de Anticorpos , Cisplatino/química , Hibridização de Ácido Nucleico , Compostos Organoplatínicos/imunologia , Sensibilidade e Especificidade
17.
Anal Biochem ; 206(1): 43-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1456440

RESUMO

A novel simple nonradioactive method for detection of specific nucleotide sequences has been developed. This method consists of the hybridization of a target DNA with a DNA probe modified with trans-diamminedichlorplatinum(II) (trans-DDP) followed by detection of DNA/DNA hybrids with affinity-isolated anti-DNA-trans-DDP antibodies and poly-horseradish peroxidase-protein A conjugate. Major advantages of this approach are the low cost and the extreme simplicity of the labeling procedure, which involves only mixing of the reagents. The sensitivity of the proposed technique is sufficient to detect 0.8 pg of DNA in Southern blot hybridization and 25 fg in dot hybridization and permits colony screening.


Assuntos
Cisplatino , Sondas de DNA , DNA/análise , Microquímica/métodos , Anticorpos , Bacteriófago lambda , Southern Blotting , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Recombinante/análise , DNA Recombinante/genética , DNA Viral/análise , DNA Viral/genética , Estabilidade de Medicamentos , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Haptenos , Técnicas Imunoenzimáticas , Hibridização de Ácido Nucleico/métodos , Radioisótopos de Fósforo , Sensibilidade e Especificidade
18.
Eur J Pharmacol ; 226(1): 5-13, 1992 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-1397055

RESUMO

Polyclonal antibodies that bind selectively to DNA modified by antitumour cisplatin and its analogues were isolated. The reactivity of the antibodies with the epitope was enhanced by thermal denaturation of DNA that had been modified by cisplatin before its denaturation. On the other hand, denaturation of DNA before its modification resulted in considerably less reaction of the antibodies. The conversion of monofunctional cisplatin-DNA adducts to bifunctional lesions increased the capability of the modified DNA to competitively inhibit the antibodies. The double-helical oligonucleotides containing a unique bifunctional adduct formed by cisplatin at the d(GG) site cross-reacted with the antibodies in contrast to the oligonucleotide containing a single monofunctional adduct formed at the d(G) site. In addition, poly(dG-dC) . poly(dG-dC) modified by cisplatin did not react with the antibodies. It was concluded that the antibodies recognized monodentate lesions, intrastrand cross-links between two purine nucleosides separated by one or more nucleosides and interstrand cross-links negligibly. The antibodies apparently recognized a chemical nature of the bifunctional adduct formed between two adjacent purines and not an unusual conformational feature of DNA resulting from the formation of this adduct. The antibodies were used to analyse the adducts formed by cisplatin on DNA of cultured cells exposed to this drug. During the subsequent incubation of the already exposed cells in the drug-free medium, a part of the bifunctional adducts of cisplatin was completely removed from DNA or transformed to the adducts not recognized by the antibodies.


Assuntos
Cisplatino/química , Dano ao DNA , DNA de Neoplasias/química , Animais , Anticorpos/imunologia , Sequência de Bases , Ligação Competitiva , Cisplatino/imunologia , Cisplatino/metabolismo , DNA de Neoplasias/imunologia , DNA de Neoplasias/metabolismo , Ensaio de Imunoadsorção Enzimática , Glioma , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/imunologia , Oligodesoxirribonucleotídeos/metabolismo , Ratos , Células Tumorais Cultivadas
19.
Probl Tuberk ; (3-4): 6-8, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1528840

RESUMO

High tuberculosis prevalence found among the convicts of penitentiary-labour establishments 20 times exceeds that found among the adult population of the Sverdlovsk region. Constant migration of patients exists between the antituberculosis institutions of the region and penitentiary-labour establishments located on its territory. Considering the fact that adequate treatment of patients with antisocial behaviour cannot be organized in tuberculosis hospitals the problem must be solved at places of confinement.


Assuntos
Prisioneiros , Tuberculose/epidemiologia , Adolescente , Adulto , Hospitalização , Humanos , Sibéria , Tuberculose/terapia
20.
Eur J Biochem ; 201(3): 723-30, 1991 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1935966

RESUMO

Polyclonal antibodies that bind selectively to adducts formed with DNA by chemotherapeutically inactive trans-diamminedichloroplatinum (II) [trans-[Pt(NH3)2Cl2]) were produced by immunization with calf-thymus double-helical DNA modified by trans-[Pt(NH3)2Cl2] at a ratio of bound platinum/nucleotide (rb) of 0.1. High selectivity was obtained by separation of the antibodies from the antiserum with the aid of affinity chromatography on a Sepharose column. The antibodies were competitively inhibited in an ELISA assay by 25 pM trans-[Pt(NH3)2Cl2] bound to double-helical DNA and 2.5 pM trans-[Pt(NH3)2Cl2] bound to denatured DNA (rb = 0.1). The conversion of monofunctional adducts, formed on DNA at the early stage of its interaction with trans-[Pt(NH3)2Cl2], to bifunctional lesions, decreased the ability of the modified DNA to competitively inhibit these antibodies. They did not cross-react with unmodified, denatured DNA, but they reacted with diethylenetriamine-chloroplatinum(II)-chloride-modified double-helical DNA and with double-helical DNA treated with cis-diamminedichloroplatinum(II) for a short time (10 min). The results of this work best fit a model in which one of the major antigenic determinants of double-helical DNA modified by trans-[Pt(NH3)2Cl2] is the platinum atom coordinated in a monodentate or bidentate manner with non-paired nucleotide residues or perhaps a short segment of single-stranded DNA which occurs around the platination site. Nucleic acids modified by trans-[Pt(NH3)2Cl2] can be used as immuno-probes in hybridization experiments.


Assuntos
Cisplatino/imunologia , DNA/imunologia , Animais , Formação de Anticorpos , Ligação Competitiva , Cisplatino/metabolismo , DNA/metabolismo , Ensaio de Imunoadsorção Enzimática , Desnaturação de Ácido Nucleico , Hibridização de Ácido Nucleico , Polarografia/métodos , Coelhos
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