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El-Aal M.A.A.,National Organization for Research and Control of Biologicals | Al-Ghobashy M.A.,Cairo University | Fathalla F.A.A.,National Organization for Research and Control of Biologicals | El-Saharty Y.S.,Cairo University
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2017

In this work pH-responsive neutral and cationic polyacrylamide molecularly imprinted polymers (nMIP and cMIP, respectively) were prepared for separation of recombinant and wild type human serum albumin (HSA, pI 4.7) using mixture of polymerization initiators. The effect of pH during preparation and adsorption stages at pI(HSA) ± 2.0 on binding capacity and selectivity; imprinting factor (IF) was thoroughly investigated. SE-HPLC and RP-HPLC were employed for thorough evaluation of the stability of HSA at the studied experimental conditions and for simultaneous determination of HSA and erythropoietin (EPO) in their mixtures, respectively. Results showed that nMIP were generally superior to cMIP, where nMIP prepared at pH 2.7 and tested at pH 6.7 showed superior binding characteristics (IF 42.91). The pH at the preparation stage imposed minimal effect on the stability of HSA owing to entrapment of HSA within the polymer network. Adsorption experiments carried out at pH 2.7, regardless of polymer type and pH of preparation revealed poor selectivity. Adsorption of HSA onto MIP followed Sips model with pseudo second-order kinetics. Scanning electron microscopy (SEM) revealed a rough surface for MIP and a smooth one with wider pore diameter for non-imprinted polymer (NIP). Successful separation of recombinant HSA from its binary mixture with EPO and wild type HSA from crude plasma was demonstrated using RP-HPLC. This suggested that MIP should be applicable for downstream purification of therapeutic grade HSA at scale either from plasma or recombinant sources and isolation of HSA from plasma for diagnostic purposes. © 2017 Elsevier B.V.


Mohareb R.M.,Cairo University | MegallyAbdo N.Y.,Alexandria University | Mohamed A.A.,National Organization for Research and Control of Biologicals
Anti-Cancer Agents in Medicinal Chemistry | Year: 2016

The following study explored the cytotoxic effect on human cancer cells of a series of novel progesterone derivatives through the synthesis of heterocyclic compounds incorporating progesterone moiety. The reaction of progesterone (1) with cyanoacetanilide derivatives gave the condensation products 3a,b. Either of compound 3a or 3b reacted with elemental sulfur affording the thiophene derivatives 4a and 4b, respectively. In addition, progesterone (1) underwent some multi-component reactions with aromatic aldehydes and cyanomethylene reagents in triethylamine to give the pyran derivatives 10a-f. Carrying the same reactions but using ammonium acetate afforded the pyridine derivatives 11a-f. The anti-tumor evaluations of the newly synthesized products were tested against six human cancer and normal cell lines. The results showed that nine compounds (3b, 7c, 10b, 10d, 10f, 11d, 13a, 13b and 14b) revealed optimal cytotoxic effect against cancer cell lines with IC50 < 550 nM and their cytotoxicity’s were higher than that of progesterone. Moreover, the toxicity of the most active compounds was measured against shrimp larvae. In addition, the anti-proliferative evaluations of these potent compounds were measured. © 2016 Bentham Science Publishers.


Mostafa M.M.,National Organization for Research and Control of Biologicals | Al-Ghobashy M.A.,Cairo University | Fathalla F.A.,National Organization for Research and Control of Biologicals | Salem M.Y.,Cairo University
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2016

Quadrivalent human papillomavirus (HPV) vaccine is formulated of four types of non-infectious recombinant virus like particles (VLPs) that are structurally and immunologically similar to the corresponding infectious HPV virus types 6, 11, 16 and 18. With almost identical physical, chemical and structural properties of the four types of VLPs, ELISA remains the only approved in vitro potency testing assay. In this study, an alternative industry-friendly, stability- and potency-indicating assay protocol was developed and validated for the determination of HPV vaccine. Vacuum-driven immunoaffinity extraction (IAE) was employed using type-specific, conformation-dependent antibodies against each type of HPV VLPs. ELISA assay was employed to evaluate the ability of IAE columns to specifically separate each of the four types of VLPs from their quadrivalent mixture. Mean percentage recoveries of 76.76. ±. 2.69, 69.12. ±. 5.79, 84.86. ±. 5.25 and 71.14. ±. 4.50% were obtained for VLPs types 6, 11, 16 and 18, respectively with no significant interference in each case. Antigen content was then determined using SE-HPLC over a concentration range of 5.00-20.00. μg/mL (r. >. 0.998) for VLPs type 6, 11, 16 and 18, respectively. The SE-HPLC assay was found accurate and precise (RSD. <. 10.00%) with LOD ranging from 1.23-3.85. μg/mL. The assay protocol was found superior to conventional ELISA assay with respect to simplicity, total analysis time and cost. Good correlation between the results of analysis obtained using IAE-SE-HPLC and ELISA demonstrated the suitability of the suggested assay protocol for stability and potency assessment with a good potential for implementation for batch release. This approach should be applicable for quality assessment of other vaccine preparations based on VLPs. © 2016 Elsevier B.V.


Shaltout E.L.,National Organization for Research and Control of Biologicals | Al-Ghobashy M.A.,Cairo University | Fathalla F.A.,National Organization for Research and Control of Biologicals | Salem M.Y.,Cairo University
Journal of Pharmaceutical and Biomedical Analysis | Year: 2014

An orthogonal testing protocol was developed and validated to assess the quality of Filgrastim biosimilars. Results were compared to those obtained from the innovator product. Initial screening was carried out using reducing and non-reducing gel electrophoresis. RP-LC was employed for the determination of Filgrastim in the presence of its oxidative degradation products. SEC and CIEF were used under non-denaturing conditions to reveal high molecular weight and charged impurities, respectively. RP-LC assay was found accurate (99.78. ±. 0.89) and precise over a linear concentration range of 9.38-300.00. μg/ml with a LOD of 8.26. μg/ml (0.44. mM). SEC was carried out over a molecular weight range of 5.0-150.0. kDa. CIEF was optimized using neutrally coated capillaries over a wide-range pH gradient (pH 3.0-10.0). Differences between the studied products were revealed using all these techniques. Impurities above the acceptable limits were detected in both biosimilar products. CIEF revealed heterogeneity in the active ingredient that has not been investigated by the manufacturers. Correlation of the obtained results indicated the presence of not only product-related impurities, but also process-related impurities. Results confirmed the need for in-house validated orthogonal testing protocols to be developed by local regulatory authorities. This should prevent access of substandard biosimilars to price-sensitive markets. © 2014 Elsevier B.V..


Mohareb R.M.,Cairo University | Mohamed A.A.,National Organization for Research and Control of Biologicals | Abdallah A.E.M.,Helwan University
Acta Chimica Slovenica | Year: 2016

The reaction of ethyl cyanoacetate with o-phenylenediamine gave the 2-cyanomethylbenzo[c]imidazole (1). The latter compound was used as the key starting material to synthesise biologically active heterocyclic derivatives. Thus, the reaction of 1 with cyclohexanone and either of benzaldehyde, 4-methoxybenzaldehyde or 4-chlorobenzaldehyde gave the annulated derivatives 2a-c, respectively. The antitumor evaluations of the newly synthesized products against the three cancer cell lines MCF-7 (breast adeno-carcinoma), NCI-H460 (non-small cell lung cancer) and SF-268 (CNS cancer) showed that compounds 2b, 6, 11b, 11c, 12b, 16a, 16b and 18a exhibited optimal cytotoxic effect against cancer cell lines, with IC50 values in the nM range. Bioactive compounds are often toxic to shrimp larvae. Thus, in order to monitor these chemicals in vivo lethality to shrimp larvae (Artemia salina), Brine-Shrimp Lethality Assay was used. Compounds 11b, 12b and 16b showed no toxicity against the tested organisms. © 2016, Slovensko Kemijsko Drustvo. All rights reserved.


Ibrahim E.H.,National Organization for Research and Control of Biologicals
The Egyptian journal of immunology / Egyptian Association of Immunologists | Year: 2011

Hepatitis E virus (HEV) is a common cause of acute viral hepatitis (AVH) in developing countries. In Egypt; where up to 80% of the inhabitants of rural villages have anti-HEV antibodies denoting past infection, most of these infections are asymptomatic with little evidence that the infection causes AVH. There are accumulating reports which suggest potential risk of HEV transmission by blood transfusion. However, detection of serological markers for HEV infection or HEV RNA in Egyptian blood banks is not routinely performed. 760 blood samples from apparently healthy donors at the National blood bank were tested for markers of acute HEV infection to estimate the seroprevalence of acute HEV infection, and potential risk of infection by blood transfusion. They included 124 females (16.82%) and 636 males (83.68%), with a mean age of 23.8 +/- 5.3 years and mean ALT value of 23.3 +/- 13.2 IU/ml. Samples were tested as pools of 10 subjects. Pools with highest reactivity were retested individually to determine the frequency of positive subjects. Out of the 760 samples, three (0.45%) samples were positive for anti-HEV IgM and two of them had HEV RNA as determined by RT-PCR. In conclusion, this study suggests that the tested blood donors have low prevalence of ongoing subclinical infection with HEV and that the potential risk of transfusion may be low.


PubMed | National Organization for Research and Control of Biologicals and Cairo University
Type: | Journal: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences | Year: 2016

Quadrivalent human papillomavirus (HPV) vaccine is formulated of four types of non-infectious recombinant virus like particles (VLPs) that are structurally and immunologically similar to the corresponding infectious HPV virus types 6, 11, 16 and 18. With almost identical physical, chemical and structural properties of the four types of VLPs, ELISA remains the only approved in vitro potency testing assay. In this study, an alternative industry-friendly, stability- and potency-indicating assay protocol was developed and validated for the determination of HPV vaccine. Vacuum-driven immunoaffinity extraction (IAE) was employed using type-specific, conformation-dependent antibodies against each type of HPV VLPs. ELISA assay was employed to evaluate the ability of IAE columns to specifically separate each of the four types of VLPs from their quadrivalent mixture. Mean percentage recoveries of 76.762.69, 69.125.79, 84.865.25 and 71.144.50% were obtained for VLPs types 6, 11, 16 and 18, respectively with no significant interference in each case. Antigen content was then determined using SE-HPLC over a concentration range of 5.00-20.00g/mL (r>0.998) for VLPs type 6, 11, 16 and 18, respectively. The SE-HPLC assay was found accurate and precise (RSD<10.00%) with LOD ranging from 1.23-3.85g/mL. The assay protocol was found superior to conventional ELISA assay with respect to simplicity, total analysis time and cost. Good correlation between the results of analysis obtained using IAE-SE-HPLC and ELISA demonstrated the suitability of the suggested assay protocol for stability and potency assessment with a good potential for implementation for batch release. This approach should be applicable for quality assessment of other vaccine preparations based on VLPs.


PubMed | National Organization for Research and Control of Biologicals and Cairo University
Type: | Journal: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences | Year: 2017

In this work pH-responsive neutral and cationic polyacrylamide molecularly imprinted polymers (nMIP and cMIP, respectively) were prepared for separation of recombinant and wild type human serum albumin (HSA, pI 4.7) using mixture of polymerization initiators. The effect of pH during preparation and adsorption stages at pI


PubMed | National Organization for Research and Control of Biologicals and Cairo University
Type: Journal Article | Journal: Journal of AOAC International | Year: 2016

A selective, rapid size-exclusion chromatographic method was developed and validated for the separation of the human growth hormone (hGH) somatropin from its high-molecular-weight aggregates. Separation was achieved using a nontoxic mobile phase compared with the official method of the European Pharmacopoeia that uses 2-propanol in a mobile phase. The developed method used a YMC-Pack Diol (YMC Karasuma, Kyoto, Japan; 300 8.0 mm, 5 m) analytical column. The mobile phase was formed with a pH 7phosphate buffer that was pumped at a flow rate of 1 mL/min with UV detection at 214 nm. The overall run time was 20 min and the average retention times were found to be 10.21 min for the monomer peak, 9.52 min for the dimer peak, and 9.14 min for the higher aggregate. This method was validated in terms of selectivity, linearity, and intra- and interday variations according to the International Conference on Harmonization guidelines. The developed method was applied as a rapid tool for evaluating the stability of stressed samples of hGH subjected to different temperature, agitation, and repeated freeze-thaw cycles. The developed method was successfully applied for the assessment of the quality and quantity of hGH during downstream processing, formulation, and storage.


PubMed | National Organization for Research and Control of Biologicals and Cairo University
Type: Journal Article | Journal: Biologicals : journal of the International Association of Biological Standardization | Year: 2016

A sandwich-type ELISA was optimized and validated to determine the in-vitro relative potency of the four-component prophylactic Human papillomavirus (HPV) vaccine. The vaccine contains the non-infectious virus like particles (VLP) corresponding to HPV Types 6, 11, 16 and 18. A modification of the desorption step required to release the VLPs from the aluminum adjuvant was carried out. Samples were incubated with citrate buffer for two hours at 37C instead of overnight incubation at room temperature. Assay validation was then carried out according to ICH guidelines. The assay was linear over a concentration range of 0.30-2000.00ng/mL for the four HPV types. The assay was accurate and precise with a LOD of 0.092, 0.081, 0.086 and 0.068ng/mL for type 6, 11, 16 and 18 respectively. Results were also statistically compared to those obtained using the reported ELISA assay and no significant difference was noted. In contrary to the reported ELISA protocol, this optimized immunoassay was superior with respect to analysis time, without affecting the accuracy and precision (RSD<5%). This assay has proven to be useful for evaluating the efficacy of the quadrivalent HPV vaccine and is applicable for quality control and batch release purposes.

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