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Hepatitis C virus is a major public health problem leading to cirrhosis and increased risk for development of hepatocellular carcinoma, both leading indications for liver transplantation. Egypt has the highest prevalence of hepatitis C of worldwide. Anti-HCV antibody is usually detected by enzyme immunoassay (EIA). Microarray analysis of 8 Anti-HCV antibody isotypes and 5 HCV peptides considered separately on 5 different matrixes was carried out on 50 hepatitis C Egyptian patients. The optimal substrate kind was chosen based on the greatest amount of antibody bonded with the minimal background. Mercaptosilane activated slides, agarose-slides and polyvinylidene difluoride membranes were the best substrates, while polyacrylamide and nitrocellulose membrane were less sensitive. IgM isotype gave the weakest signals in all patients whatever the substrate type used for antibody immobilization while IgG (total) and its subtypes IgG2, IgG3 and IgG(4) gave the strongest signals with most of the substrates follows by IgA(1), IgG(1) and total IgA, respectively. The results demonstrate that IgG2, IgG3 and IgG(4) are the dominant IgG subtypes, which may indicate that HCV patient immune response shift toward Th-2 immunity. The microarrays permitted the simultaneous serodetection of hepatitis C virus core and envelope peptides by using corresponding rabbit anti-peptides. Hepatitis C virus core and envelope peptides 1, 2, 3, 4 and 5 showed strong signals on all the used substrates except for polyacrylamide slides and nitrocellulose membranes.

By definition, biopharmaceuticals includes the recombinant therapeutics proteins, monoclonal antibody and nucleic acid based-products used for medical purposes, which produce through the biotechnology. It has grown enormously during last 25 years, even that each four pharmaceuticals product contains one biopharmaceutical product. This class of therapeutical generates in excess of $50 billion in sales annually. About 150 biopharmaceuticals have now received the medical approval. Actually, this white dimension is supported with strong RD. The cost-estimated of total RD per single biopharmaceutical approved molecule will reach $1318 million. The majority of these materials are development and producing in mammalian cell line (70%), prokaryotic systems (15%), and yeast (5%), respectively. Few products are animal-derived, however the rest are completely from human-genes or humanized.

Polymeric immunoglobulin (dimeric IgA and pentameric IgM) molecules can assembly by using the immunoglobulin J (joining) chain and across the epithelial cell layers. Based on its amino acid and gene sequences data, disulfide bond (2 bonds) assignment secondary structure predictions, and chemical properties, a model for J-chain folding has been proposed. However, the crystal structure of the J-chain protein is still far from obtained, because the J-chain expression and its protein downstream has a permanent aggregation problems, due to its two free thiol groups. Our work focused on the chemical blocking of free cysteines-SH or to mutate these cysteines into serine residues. The chemical blocking yielded partially soluble proteins with new structures (carboxyamidomethyl cysteine and carboxyamidomethyl methionine) at cysteine and methionine residues. While mutate the cysteines into serine has been yielded a complete soluble (11.5 mg/l) J-chain protein which migrate (SDS-PAGE) at 27 KDa. We were used pET22b expression vector and E. coli BL21 (DE3) to produce the J-chain protein. For maximization the production yield of j-chain foreign protein, the batch culture was developed. We described the scaling-up production in term of kinetic behavior to the recombinant E.coli and optimization of cultivation parameters in 3-L bench-top bioreactor. The process was automated through a computer aided data bioprocessing system AFS-BioCommand multi-process management program to regulate the cell growth rate, temperature, pH and agitation speed based on dissolved oxygen. The results showed an obvious increasing in biomass by 5.98 g/L after about 27 h [corrected]

To establish a cell culture system with long-term replication of hepatitis C virus (HCV) genome and expression of viral antigens in vitro.HepG2 cell line was tested for its susceptibility to HCV by incubation with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various time points during the culture. Culture supernatant was tested for its ability to infect naive cells. The presence of minus (antisense) RNA strand, and the detection of core and E1 antigens in cells were examined by RT-PCR and immunological techniques (flow cytometry and Western blot) respectively.The intracellular HCV RNA was first detected on d 3 after infection and then could be consistently detected in both cells and supernatant over a period of at least three months. The fresh cells could be infected with supernatant from cultured infected cells. Flow cytometric analysis showed surface and intracellular HCV antigen expression using in house made polyclonal antibodies (anti-core, and anti-E1). Western blot analysis showed the expression of a cluster of immunogenic peptides at molecular weights extended between 31 and 45 kDa in an one month old culture of infected cells whereas this cluster was undetectable in uninfected HepG2 cells.HepG2 cell line is not only susceptible to HCV infection but also supports its replication in vitro. Expression of HCV structural proteins can be detected in infected HepG2 cells. These cells are also capable of shedding viral particles into culture media which in turn become infectious to uninfected cells.

In Egypt, the incidence of invasive Haemophilus influenzae type b (Hib) disease is not common and the vaccine is still not included into the national immunization program. The aim of this study was to evaluate the natural immunity to Hib in healthy children at Egyptian capitol (Cairo). One hundred and two children were enrolled in our study of age one month to 15 year. Anti-capsular polysaccharide (PRP) of Hib specific IgM and IgG antibody concentrations were estimated using enzyme immunoassay. The majority (64.7%, 75.5%) of children had a protective levelsor=15 microg/ml of specific antibodies (IgM and IgG). Fortunately, a total of 95.5% of the children under 5 years old had a protective level. Our result will provide evidence that in Egypt capitol, the natural immunity against Hib can be acquired at an early age.

We designed two synthetic-core-specific peptides core 1 (C1) and core 2 (C2), and an E1-specific peptide (E1). We produced specific polyclonal antibodies against these peptides and used the antibodies for detection of HCV antigens on surface and within infected peripheral blood leukocytes.Peripheral blood from a healthy individual who tested negative for HCV RNA was incubated with HCV type 4 infected serum for 1 h and 24 h at 37 degrees C. Cells were stained by direct and indirect immunofluorescence and measured by flow cytometry.After 1 h of incubation, antibodies against C1, C2, and E1 detected HCV antigens on the surface of 27%, 26% and 73% of monocytes respectively, while 10%, 5% and 9% of lymphocytes were positive with anti-C1, anti-C2 and anti-E1 respectively. Only 1-3% of granulocytes showed positive staining with anti-C1, anti-C2 and anti E1 antibodies. After 24 h of incubation, we found no surface staining with anti-C1, anti-C2 or anti-E1. Direct immunostaining using anti-C2 could not detect intracellular HCV antigens, after 1 h of incubation with the virus, while after 24 h of incubation, 28% of infected cells showed positive staining. Only plus strand RNA was detectable intracellularly as early as 1 h after incubation, and remained detectable throughout 48 h post-infection. Interestingly, minus RNA strand could not be detected after 1 h, but became strongly detectable intracellularly after 24 h post-infection.Monocytes and lymphocytes are the preferred target cells for HCV infection in peripheral blood leukocytes. Our specific anti-core and anti-E1 antibodies are valuable reagents for demonstration of HCV cell cycle. Also, HCV is capable of infecting and replicating in peripheral blood mononuclear cells as confirmed by detection of minus strand HCV RNA as well as intracellular staining of core HCV antigen.

Our aim was to determine the level of tetanus immunity in the general Egyptian population. The surveyed population consisted of 709 healthy subjects from five regions of Egypt, 2 month to 105 years of age. We used an ELISA assay to determine titers of anti-tetanus IgG. According to the widely used criteria, 31.7% was susceptible to tetanus (IgG level0.15 IU/ml), 15.7% protection (0.15-1.0 IU/ml), and 52.6%or = 1.0 IU/ml). The results revealed that the majority (68.3%) population from 2 months to 50 years had a protective level of IgG against tetanus. The level of susceptibility increases with age until it reaches 90.3% Significantly, more males (23.7%) unprotected against tetanus. Our results suggest that monitoring immunization status and administering the tetanus vaccine as required are essential to insure adequate and long-lasting antibody levels.