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The development of highly sensitive diagnostic systems for the early revelation of diseases in humans is one of the most important tasks of modern biomedical research, and the detection of the core antigen of the hepatitis C virus (HCVcoreAg)—a protein marker of the hepatitis C virus—is just the case. Our study is aimed at testing the performance of the nanoribbon biosensor in the case of the use of two different types of molecular probes: the antibodies and the aptamers against HCVcoreAg. The nanoribbon sensor chips employed are based on "silicon-on-insulator structures" (SOI-NR). Two different HCVcoreAg preparations are tested: recombinant β-galactosidase-conjugated HCVcoreAg ("Virogen", Watertown, MA, USA) and recombinant HCVcoreAg ("Vector-Best", Novosibirsk, Russia). Upon the detection of either type of antigen preparation, the lowest concentration of the antigen detectable in buffer with pH 5.1 was found to be approximately equal, amounting to ~10−15 M. This value was similar upon the use of either type of molecular probes. [ABSTRACT FROM AUTHOR]

The development of highly sensitive diagnostic systems for the early revelation of diseases in humans is one of the most important tasks of modern biomedical research, and the detection of the core antigen of the hepatitis C virus (HCVcoreAg)—a protein marker of the hepatitis C virus—is just the case. Our study is aimed at testing the performance of the nanoribbon biosensor in the case of the use of two different types of molecular probes: the antibodies and the aptamers against HCVcoreAg. The nanoribbon sensor chips employed are based on “silicon-on-insulator structures” (SOI-NR). Two different HCVcoreAg preparations are tested: recombinant β-galactosidase-conjugated HCVcoreAg (“Virogen”, Watertown, MA, USA) and recombinant HCVcoreAg (“Vector-Best”, Novosibirsk, Russia). Upon the detection of either type of antigen preparation, the lowest concentration of the antigen detectable in buffer with pH 5.1 was found to be approximately equal, amounting to ~10−15 M. This value was similar upon the use of either type of molecular probes.

Background and objective HCV is transmitted mainly by parenteral routes. However, unprotected anal intercourse has also been identified as a risk factor for HCV infection. HCV RNA can be detected in blood, saliva, and bile, but the presence of HCV in stool has not been investigated yet. Study design Therefore, stool samples of 98 patients were collected prospectively. Specific HCV primers were used to identify samples positive for HCV RNA. HCV RNA-positive samples were tested for HCVcoreAg with the Architect HCVAg assay (Abbott). Presence of occult blood was investigated by the hemoCARE guajak test. Viral stability and infectivity of recombinant HCV particles was investigated in vitro by incubation of genotype 2a chimeric virus Jc1 with bile and stool suspensions. Results HCV RNA could be detected in 68 out of 98 stool samples from patients with chronic hepatitis C and 16 samples also tested positive for HCVcoreAg. Presence of HCV RNA in stool was more frequent in male than in female and in patients with low platelet counts but was not associated with the detection of occult blood. Stool suspensions and to a lesser extent bile reduced the in vitro infectivity of genotype 2a chimeric Jc1 virus even though infection of Huh7 cells was not completely abrogated. Conclusions In summary, this study shows for the first time that HCV can frequently be detected in stool samples of chronically infected patients irrespective of occult bleeding. We suggest that stool can be a potential source for HCV infection and thus unprotected anal intercourse should be avoided. [ABSTRACT FROM AUTHOR]

Background. Hepatitis C virus (HCV) and hepatitis B virus (HBV) infections are common in haemodialysis units. Moreover, some studies reported seronegative cases of viral hepatitis. We and others have previously shown an HCV RNA decline during haemodialysis; however, limited data on HBV viraemia during haemodialysis are available.Methods. A total of 142 haemodialysis patients participated in this study, 11 were anti-HCV positive and 7 were HBsAg positive. HCV RNA and HBV DNA were determined in all patients irrespective of hepatitis serology. HBV DNA, HCV RNA, HBsAg and HCV core antigen (HCVcoreAg) were quantified repeatedly in anti-HCV- and HBsAg-positive patients before and after haemodialysis.Results. No case of seronegative viral hepatitis could be identified. HCV RNA was detected in 9 of the 11 anti-HCV-positive patients, while HBV DNA tested positive in all 7 HBsAg-positive patients. A decrease of HCVcoreAg was observed during four dialysis sessions in 8/9 patients (−24.4 ± 22.7%, P < 0.001) parallelled by HCV RNA decline in most individuals (−10.1 ± 48.6%, P = 0.22). In contrast, HBV DNA and HBsAg declined only in 1/7 patients during all four independent measurements. The remaining six patients showed heterogeneous patterns of HBV DNA and HBsAg before and after haemodialysis without a significant change in mean HBV DNA and HBsAg levels (+14 ± 60.6% and −0.2 ± 25.3%, P > 0.05, respectively). HCVcoreAg correlated strongly with HCV RNA (r = 0.937; P < 0.001, n = 72), while there was no correlation between HBV DNA and HBsAg (r = −0.234; P = 0.131, n = 43).Conclusions. Seronegative viral hepatitis is rare in German maintenance haemodialysis patients. HCV RNA and HCVcoreAg decline during haemodialysis indicating a potential beneficial effect of haemodialysis during antiviral therapy of hepatitis C, which does not apply to HBV infection. [ABSTRACT FROM AUTHOR]

Herein, we have demonstrated highly sensitive real-time biospecific detection of a protein marker of hepatitis C—the core antigen of hepatitis C virus (HCVcoreAg)—using a nanowire (NW) biosensor. The primary element of the NW-biosensor is a chip with p-type conductance, bearing silicon-on-insulator (SOI) nanowire structures on its surface. The nanowire structures are fabricated by gas-plasma treatment and electron beam lithography. The detection specificity was provided by sensitization of the sensor surface with aptamers against HCVcoreAg. The influence of buffer pH on the sensor response signal was studied. The effect of reverse polarity of the biosensor response signal with change from the acidic buffer pH to the neutral one was found. The lowest detectable HCVcoreAg concentration was determined to be 2.0 × 10−15 M in both acidic (pH 5.1) and neutral (pH 7.4) buffer solution. The proposed aptamer-sensitized sensor was also successfully applied to detect HCVcoreAg in serum samples of hepatitis C patients. [ABSTRACT FROM AUTHOR]

Complicated and large-scale challenge the contemporary biomedical community faces are development of highly-sensitive analytical methods for detection of protein markers associated with development of pathogenic mechanisms [2]. The atomic force microscopy (AFM) method in combination with specific fishing is unique among other analytical protein detection approaches; it allows visualization and counting of single protein molecules [3-6]. The present dataset focus on mass spectrometry method for detection of human hepatitis C virus core antigen (HCV core Ag) taking into account the potential modification with cations in blood serum samples, using mica chips for the atomic force microscopy (AFM-chips). To conduct specific protein fishing, we used flat AFM-chips preliminary sensibilized with molecular probes - aptamers, which are single-stranded DNA sequences. In our study we used four types of aptamers up to 85 nucleotides specific against the target protein - HCVcoreAg [3,4]. Working (n = 19) and control (n = 11) AFM-chips with aptamers were preliminarily immobilized on the surface in four zones and incubated in blood serum samples (See Supplementary fig. 1). Analysis of MS data regarding modification of marker protein peptides with Na+, K+, K2Cl+, and Na2Cl + ions enables to enhance the reliability of target proteins detection in the serum thereby demonstrating a high diagnostic potential.