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Dive into the research topics where Ashraf Tabll is active.

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Featured researches published by Ashraf Tabll.


Journal of Immunoassay & Immunochemistry | 2007

Camel Lactoferrin Markedly Inhibits Hepatitis C Virus Genotype 4 Infection of Human Peripheral Blood Leukocytes

Elrashdy M. Redwan; Ashraf Tabll

Abstract Hepatitis C virus (HCV) is a serious worldwide health risk and, to date, no effective treatments to prevent progression to chronic infection have been discovered. To combat the disease, Egyptian patients often use traditional medicines, for instance, camel milk, which contains lactoferrin. Currently, lactoferrin is one of the primary biopharmaceutical drug candidates against HCV infection. Camel lactoferrin (cLf) purification and biochemical and immunological characterization have shown its similarity to human and bovine lactoferrin, and crossreacts with the anti‐human lactoferrin antibody. Incubation of human leukocytes with cLf then infected with HCV did not prevent the HCV entry into the cells, while the direct interaction between the HCV and cLf leads to a complete virus entry inhibition after seven days incubation. Our results suggest that the cLf may be one of the camel milk components having antiviral activity. In conclusion, we have demonstrated the potential for cLf to inhibit HCV entry into human leukocytes with more efficiency than human or bovine lactoferrin.


Hepatitis Monthly | 2012

Association of IL28B SNP With Progression of Egyptian HCV Genotype 4 Patients to End Stage Liver Disease

Mostafa K. El-Awady; Lotiaf Mostafa; Ashraf Tabll; Tawfeek H. Abdelhafez; Noha G. Bader El Din; Naglaa Zayed; Reem El Shenawy; Yasmin El Abd; Reham M. Hasan; Hosam Zaghlol; Hesham El Khayat; Ashraf O. Abdel Aziz

Background IL28B single nucleotide polymorphisms (SNPs) play important roles in the management of hepatitis C virus (HCV) infections and are strongly associated with spontaneous and treatment-induced HCV clearance. Objectives In the present study, the association between IL28B variants and the progression of HCV infection in Egyptian patients infected with type 4a virus will be examined. Patients and Methods Frequencies of the protective genotype C/C of SNP, rs12979860 were determined in healthy subjects, spontaneous resolvers, and chronic HCV type 4 patients with low F scores and in patients with end stage liver disease (ESLD). This study included a total of 404 subjects. Patients infected with HCV type 4a (n = 304) were divided into; chronic hepatitis C (CHC) with low F scores (CHC, n = 110), end stage liver disease (n = 110), liver cirrhosis (LC) (n = 35) and hepatocellular carcinoma (HCC) patients (n = 75), spontaneous resolvers of HCV infection (n = 84) were also included. A healthy group representing the Egyptian population (n = 100) was also included in the genotyping of IL28B. The later was typed via a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay analysis on purified genomic DNA extracted from all individuals. Results A significant increase (P < 0.0005) was observed in frequencies of IL-28B rs12979860 C/C genotypes in the healthy population, than in the CHC, LC and HCC groups (C/C = 48%, 13%, 0%.and 0% respectively). On the other hand the C/C genotype was significantly higher (P < 0.0005) in spontaneous resolvers than in healthy subjects. A comparable significant increase in the frequency of C/T allele accompanied by mild elevation of T/T allele frequency, were detected along the progression towards ESLD. Conclusions Genotype C/C is associated with viral clearance during acute infection. The sharp decline in the C/C genotype from healthy to CHC subjects and the total absence of the C/C genotype in ESLD suggests a central role of this genotype against HCV disease progression.


Cancer Detection and Prevention | 2003

Detection of serum p53 protein in patients with different gastrointestinal cancers.

Abdelfattah M. Attallah; Mohamed M. Abdel-Aziz; Amina Mohamed El-Sayed; Ashraf Tabll

Overexpression of p53 has been found in many types of human malignancy. The present study aimed to detect preoperative serum p53 among 158 patients with different gastrointestinal cancers using ELISA technique based on mouse anti-p53 DO-7 monoclonal antibody and anti-p53 rabbit polyclonal antibody. A single band of 53kDa was detected in nuclear protein tissue extracts of selected cancer patients and in 96% of the corresponding sera using Western blot assay. The ELISA technique revealed that the serum p53 was detected in 100% of patients with cholangiocarcinoma, 76% of pancreatic carcinoma, 75% of hepatocellular carcinoma, 70% of colon cancer, 60% of esophagus carcinoma, and 35% of gastric carcinoma. The serum p53 concentrations of the positive patients were highly elevated (P<0.001) compared with healthy individuals. These results suggest that immunodetection of serum p53 could be valuable for post-operative monitoring during follow up in preoperatively positive patients with gastrointestinal cancers.


Journal of Gastroenterology and Hepatology | 2011

Single nucleotide polymorphism at exon 7 splice acceptor site of OAS1 gene determines response of hepatitis C virus patients to interferon therapy

Mostafa K El Awady; Mohamed A Anany; Gamal Esmat; Naglaa Zayed; Ashraf Tabll; Amr Helmy; Abdel Rahman El Zayady; Mohga S Abdalla; Hayat M. Sharada; Maissa El Raziky; Wafaa El Akel; Shadia Abdalla; Noha G. Bader El Din

Background and Aim:  Response to interferon therapy and disease progression in hepatitis C virus (HCV) infected patients differs among individuals, suggesting a possibility of a contribution of host genetic factors. 2′‐5′‐oligoadenylate synthetase 1 (OAS1), an important component of the innate immune system with a proven antiviral function, may therefore have a relationship with the response to interferon therapy and clinical course of HCV disease. Our aim was to determine the frequency of single nucleotide polymorphism (SNP) at exon 7 splice acceptor site (SAS) of the OAS1 gene in relation to the interferon response and status of HCV infection.


BMC Infectious Diseases | 2006

Soluble egg antigen of Schistosoma Haematobium induces HCV replication in PBMC from patients with chronic HCV infection

Mostafa K. El-Awady; Samar S Youssef; Moataza H Omran; Ashraf Tabll; Wael T El Garf; Ahmed M. Salem

BackgroundThis study was conducted to examine, in vitro , the effect of soluble egg antigen (SEA) of S. haematobium on intracellular HCV RNA load in peripheral mononuclear cells (PBMC) as well as on cell proliferation in patients with chronic HCV infection.MethodsPBMC from 26 patients with chronic HCV infection were cultured for 72 hours in presence and absence of 50 μg SEA/ml medium. Intracellular HCV RNA quantification of plus and minus strands was assessed before and after stimulation. PBMC from five healthy subjects were cultured for 7 days, flow cytometric analysis of DNA content was used to assess the mitogenic effect of SEA on PBMC proliferation compared to phytoheamaglutinine (PHA).ResultsQuantification of the intracellular viral load showed increased copy number/cell of both or either viral strands after induction with SEA in 18 of 26 patients (69.2%) thus indicating stimulation of viral replication. Flow cytometric analysis showed that mean ± S.D. of percent values of cell proliferation was induced from 3.2 ± 1.5% in un-stimulated cells to 16.7 ± 2.5 % and 16.84 ± 1.7 % in cells stimulated with PHA and SEA respectively.Conclusionthe present study supports earlier reports on SEA proliferative activity on PBMC and provides a strong evidence that the higher morbidity observed in patients co-infected with schistosomiasis and HCV is related, at least in part, to direct stimulation of viral replication by SEA.


Journal of Gastroenterology and Hepatology | 2011

Human cytomegalovirus infection inhibits response of chronic hepatitis-C-virus-infected patients to interferon-based therapy

Noha G. Bader El Din; Mai Abd El Meguid; Ashraf Tabll; Mohamed A Anany; Gamal Esmat; Naglaa Zayed; Amr Helmy; Abdel Rahman El Zayady; Ahmed Barakat; Mostafa K El Awady

Background and Aim:  Cytomegalovirus (CMV) is a ubiquitous pathogen that infects the majority of humans. Co‐infection of CMV and hepatitis C virus (HCV) may deteriorate the prognosis of HCV‐infected patients. This study was conducted to examine the role of CMV reactivation in determining the response rate to treatment with interferon and ribavirin therapy in chronic HCV patients.


World Journal of Gastroenterology | 2013

IL28B polymorphism and cytomegalovirus predict response to treatment in Egyptian HCV type 4 patients.

Mostafa K El Awady; Noha G. Bader El Din; Ashraf Tabll; Yaser El Hosary; Ashraf O. Abdel Aziz; Hesham El Khayat; Mohsen Salama; Tawfeek H. Abdelhafez

AIM To test whether the status of positive cytomegalovirus (CMV) DNA detection adds to the predictive value of IL28B and to further categorize C/T allele carriers. METHODS This study included 166 chronic hepatitis C (CHC) patients who received combined interferon and ribavirin therapy for 48 wk, 84 spontaneous hepatitis C virus (HCV) resolvers who were positive for IgG anti-HCV antibody and negative for HCV RNA, and 100 healthy subjects who were negative for both HCV antibodies and RNA as controls. Genomic DNA from peripheral blood was used for IL28B rs.12979860 single nucleotide polymorphism (SNP) and CMV DNA detection. A 139 bp fragment containing IL28B SNP was amplified in all subjects by polymerase chain reaction using a specifically designed primer. Then the IL28B rs.12979860 SNP was detected by restriction fragment length polymorphism (RFLP) genotyping. The presence of CMV DNA was tested by amplification of the gB1 gene using nested polymerase chain reaction. The role of CMV and IL28B rs.12979860 SNP genotypes in determining the response rate to combined interferon therapy and clinical status of patients were statistically analyzed. RESULTS Current data showed that 67% of patients carrying the IL28B 12979860 C/C allele had a sustained viral response (SVR) while the genotypes C/T and TT were associated with lower SVR rates, 50% and 48%, respectively. SVR rates for the C/C allele were lower than other HCV genotypes and/or other populations. Genotype CC was associated with the response to interferon (P = 0.025). Genotype C/C was reduced from 48% in controls to 14% in CHC patients suggesting its protective role against progression to chronicity. The majority of spontaneously cleared subjects (86%) were C/C, confirming its protective role. The C/T allele was present in 71% of CHC patients compared with 38% of controls, so the use of IL28B SNP genotyping only in these patients may be of little value as a predictor of response. CMV reactivation occurred in 40% of CHC patients. Co-infection with CMV seriously diminished the response to interferon (IFN) therapy, with SVR rates in C/C genotypes 87.5% in CMV-negative patients and 12.5% in CMV-positive patients (P < 0.0001). SVR rates among C/T carriers were reduced to < 50% in patients with positive CMV DNA while the non-response rate doubled. These data indicate that a supplemental assay for CMV viremia adds to the prognostic value of IL28B genotyping. CONCLUSION The results suggest that both genetic (i.e., spontaneous) and therapeutic (IFN-based therapy) arms are complementary in the battle against HCV. CMV DNA testing may be of value to better predict the response to IFN, particularly in IL28B C/T carriers.


Cancer Letters | 1999

DNA ploidy of liver biopsies from patients with liver cirrhosis and hepatocellular carcinoma: a flow cytometric analysis

Abdelfattah M. Attallah; Ashraf Tabll; Samia Salem; Mohamed El-Sadany; Talaat A Ibrahim; Sanaa Osman; Ibrahem M El-Dosoky

Flow cytometric DNA analysis was used to assess cellular kinetics of needle liver biopsies from patients with liver cirrhosis and hepatocellular carcinoma (HCC). An abnormal DNA content was shown in 44.5% of liver cirrhosis cases and in 78.6% of tumor sites. The number of proliferating cells (S + G2M%) was significantly increased in cirrhotic liver (P < 0.05). Dysplasia was found in 66% of cirrhotic specimens. All negative dysplasia specimens showed a diploid pattern while 69% of positive dysplastic specimens were aneuploid (P < 0.001). In conclusion, cell proliferation, aneuploidy and liver cell dysplasia are important indicators in liver cirrhosis for the development of HCC.


Journal of Immunoassay & Immunochemistry | 2003

A novel antigen detection immunoassay for field diagnosis of hepatitis C virus infection.

Abdelfattah M. Attallah; Hisham Ismail; Ashraf Tabll; Gamal Shiha; Ibrahim El-Dosoky

Abstract The limitations of dominant methods-based on the detection of anti-HCV antibodies or HCV viremia currently used for the diagnosis of HCV infection enhance efforts to have a rapid, simple, sensitive, and specific alternative diagnostic approach to detect viral antigens. A highly reactive IgG antibody was raised to HCV-NS4 recombinant antigen. The produced antibody showed no cross-reactivity with the other HCV structural and nonstructural recombinant antigens (C1 + 2, C3 + 4, E2/NS1, NS3, NS5). The well established ELISA technique was adapted to detect the new target HCV-NS4 antigen in serum samples. Extremely high agreement was found between the results of ELISA and qualitative detection of HCV-RNA, using a RT-PCR test as a gold standard for the diagnosis of HCV infection. Based on these encouraging results, a novel enzyme immunoassay; dot-ELISA was developed for rapid (˜5 min) and simple qualitative detection of the target HCV antigen in serum. The developed method detected the HCV target antigen in 95% of serum samples from HCV infected individuals, with a specificity of 97% using sera of noninfected individuals in comparison with PCR test. The antigen detection method showed high predictive values of positive (99%) and negative (90%). Moreover, the dot-ELISA could detect the HCV target antigen in sera negative for anti-HCV Abs, but positive for HCV-RNA, and in sera of HCV infected individuals with low viremia, as well as those with high viremia, using quantitative RT-PCR. Accordingly, the developed highly sensitive and specific HCV antigen detection method could be applied for mass screening of HCV infection.


Journal of Immunoassay & Immunochemistry | 2003

Rapid and simple detection of a Mycobacterium tuberculosis circulating antigen in serum using dot-ELISA for field diagnosis of pulmonary tuberculosis.

Abdelfattah M. Attallah; Camelia A. Abdel Malak; Hisham Ismail; Abeer H. El-Saggan; Mohamed M. Omran; Ashraf Tabll

Abstract Tuberculosis (TB) has re-emerged as a major health problem worldwide. Developing an easy, inexpensive immunodiagnostic test is extremely important for TB diagnosis, especially in developing countries. A target mycobacterial circulating antigen of 55-kDa molecular weight was identified in sera from confirmed Mycobacterium tuberculosis infected individuals by using Western blotting based on a specific mouse IgG anti-M. tuberculosis monoclonal antibody (TB-55 mAb). No bands were identified in sera of healthy individuals. The target TB antigen was isolated and characterized as a protein. It consists of 15 amino acids; 24.6% of the amino acids are hydrophobic and 46.4% are hydrophilic. A dot-ELISA format, based on TB-55 mAb, was developed for the direct demonstration of the 55-kDa TB antigen in serum samples of pulmonary TB patients. The technical aspects of the developed dot-ELISA are simple, rapid (5 min), and reproducible, as well as sensitive (87%) and specific (93%). Using the more sensitive immunoassay; Western blot, the 55-kDa TB antigen was detected in all (100%) sera that have been shown false negative by dot-ELISA, as well as in true positive sera. In conclusion, we have developed a simple and rapid immunoassay for the direct detection of a circulating mycobacterial antigen in sera of TB infected individuals and, therefore, the developed assay can be applied for laboratory and field diagnosis of TB infection in developing countries.

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Mostafa K El Awady

Theodor Bilharz Research Institute

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