Effect of thimerosal on vaccine antigen activity and its mechanism / 中国生物制品学杂志

@#Abstract： Thimerosal is commonly used as a preservative in biological products，especially in vaccines. Although it has been removed from single ⁃ dose vaccines in most countries，thimerosal is still widely used in multi ⁃ dose vaccines at present. Thimerosal，as a component in vaccine preparation，should be compatible with other components，especially should not damage the activity of antigen. However，in recent years，many studies have reported that thiomersal can reduce the antigenicity and immunogenicity of vaccine antigens，especially protein antigens containing or rich in cysteine（Cys）， suggesting that the effect of thimerosal on vaccine antigen activity should be fully evaluated when it is used as a vaccine preservative. In this paper，the effects of thimerosal on antigenicity and immunogenicity of two inactivated vaccines and three recombinant protein vaccines and the possible mechanisms were reviewed，in order to provide reference for rational selection of vaccine preservatives.

The Inductive Effect of Purified Streptococcal M-protein on Immunity against Streptococcus pyogenes in Rabbit Model.

Aims: The study aimed to know the effects of the purified M-protein on immune system to produce protection against Streptococcus pyogenes in rabbits. Study Design: Case-control study. Place and Duration of Study: In this study, collection samples and bacterial identification were carried out in two hospitals; Child Protection Hospital and Central Child Hospital in Baghdad city, and experimental work was done in Department of Medical Microbiology, College of Medicine-Babylon university, Iraq. The study was done during the period between January to July 2014. Methodology: A total of 260 samples were collected from tonsillitis and pharyngitis cases. Three main parts involved in this study: the first part is bacterial diagnosis based on relied diagnostic procedures. The second part is detection of serogroup of GAS and antistreptolysin O (ASO) antibodies by using latex agglutination test, and the third part is experimental study conducted on the protective immune response against the group A streptococci using rabbit model. M-protein was purified by using Ion exchange chromatography. The rabbit models were immunized with purified M protein according to standard method. The immune response generated against the M protein was checked in an rabbit population. Results: From a total of 260 samples of tonsillitis and pharyngitis cases among children, only 8 (3.07%) isolates were identified as Streptococcus pyogenes. High amount of M-protein was detected in two isolates by indirect bacterial test. The concentration of purified M-protein ranged from 20-24.68 µg/ml. The purified M protein has important role in an induction of the immune response in experimental model. It leads to increased phagocytosis, stimulation of T-cell, and high level of antibody in serum of an immunized rabbits. Conclusion: The purified streptococcal M protein has strong antigenicity, and it has important role in an induction the strong protective immune response in experimental rabbit model. It may be used in future studies as vaccine against streptococcal infection among humans.

Early dengue diagnosis by nonstructural protein 1 antigen detection: Rapid immunochromotography versus two the enzyme-linked immunosorbent assay kits.

Dengue is known for its serious life-threatening complications. New rapid kits available recently in India target circulating non-structural protein (NS1) antigen from day one onwards. The sensitivity and specifi city of a newly introduced rapid combo kit against two conventional ELISA kits is assessed. The performance of this kit is quite satisfactory since excellent agreement of 94.26% was observed with particular reference to NS1 antigen detection among all three kits namely Rapid SD Bioline dengue Duo (SD Korea), InBios DENV Detect NS1 ELISA, USA and dengue Early ELISA, Panbio, Australia. The false positivity of the rapid kit is very low since its specifi city as for as NS1 antigen detection is concerned is 98.33%. The use of combination kit helps to detect additional cases of dengue, which are negative for NS1 antigen but positive for IgM and/or IgG antibodies, thus facilitating early diagnosis in remote areas and small laboratories.

Screening of human phage single chain antibody against the recombinant surface protein of Streptococcus mutans and identification of its biological activities / 中国人兽共患病学报

To isolate human phage single chain antibody against surface protein of Streptococcus mutans,the recombinant surface protein of S.mutans(rAP) was used to coat the immune tubes and the phage single chain antibody was prepared through pDAN5 phage antibody library after 5 rounds of panning.The eluted phage was enriched nearly 30 times.In these ways,13 positive clones were obtained and found to be able to bind with rAP in ELISA assay.Then one of the 13 positive clone phage plasmid was used to infect E.coli HB2151 to induce the expression of the non-fusion single chain antibody (ScFv) with IPTG induction.As demonstrated by SDS-PAGE,the molecular mass of this single chain antibody was proved to be 30 kDa and the amount of expression constituted to 30% of the total bacterial proteins.Apparently,the human phage single chain antibody against surface protein of S.mutans with biological activity was successfully screened.

An experimental study of BALB/c mice immunized by vaccine gene pcDNA3- PAc against dental caries through different routes / 实用口腔医学杂志

Objective:To observe the anticaries effects of the vaccine gene pcDNA3- PAc against dental caries in BALB/c mice by different routes. Methods: BALB/c mice were immunized with the recombinant plasmid pcDNA3- PAc by the submandibular gland- target injection,the quadriceps femoris injection and the intranasal irrigation respectively. All the mice were immunized two times. The immune interval was two weeks. Saliva and serum samples were collected respectively at 0, 1, 2, 4 weeks after immunization. The specific antibodies were detected by ELISA. Results:The specific antibodies were up at one week after immunization in different routes. The peak time of the antibodies level appeared at 4 weeks.The level of salivary specific anti- PAc IgA induced by submandibular gland- target injection and that of serum IgG induced by thigh bone muscle injection was the highest, respectively. The differences of antibodies level between in experiment groups and negative control group or vacant comparison group were significant(P<0.01). Conclusion: The vaccine gene pcDNA3- PAc effectively induce local mucosal immune response and systemic immune response.

Purification of Native Ag85 Complex, 38-kDa and MTB12 Protein Antigens from the Culture Filtrate of Mycobacterium tuberculosis

The purification of immunodominant native protein antigens from the culture filtrates of Mycobacterium tuberculosis is needed for the development of new vaccines and immunodiagnostic reagents against tuberculosis. In the present study, we conducted large scale purification of well-known secreted antigens, Ag85 complex, 38-kDa, and MTB12, from the culture filtrate proteins (CFPs) prepared from M. tuberculosis H37Rv grown as a surface pellicle on synthetic Sauton medium. The protein and antigen concentrations of culture filtrates were sufficiently increased after 6 week of culture. The MTB12 antigen was detected as early as 1 week of culture, and Ag85 complex and 38-kDa antigen were detected after 2 and 3 week of culture, respectively, by immunodiffusion with specific antiserum against 100-fold concentrated culture filtrates. For large-scale purification, the six-week-culture filtrates of M. tuberculosis H37Rv diluted 2.5-fold with 20 mM Tris-HCl, (P)H 8.3 were subjected to anion-exchange chromatography. The CFPs were eluted with 100 mM NaCl-20 mM Tris-HCl, pH 8.3 and concentrated by ultrafiltration. The concentrated CFPs were fractionated with ammonium sulfate, and followed by hydrophobic interaction chromatography and anion-exchange chromatography (FPLC). Eventually, 10 mg of Ag85 complex, 0.56 mg of 38-kDa, and 1.81 mg of MTB12 antigens were purified from 1 liter of the six-week-culture filtrates of M. tuberculosis H37Rv which contained 307.81 mg of protein of culture filtrate.

An Analysis of p53, bcl-2 and Ki-67 Expressions, and Apoptosis in Rectal Cancer: Their Correlation with the Tumor Response after Preoperative Radiochemotherapy

Background : Preoperative radiochemotherapy (RCT) has been administered for locally advanced rectal cancer to increase the therapeutic benefits, and to preserve the sphincter in low-lying tumors, however, tumor responses after RCT are variable. Methods : Apoptotic index (AI), and expressions of Ki-67, p53 and bcl-2 were analyzed in pretreatment biopsies from 69 patients with rectal cancer by immunohistochemistry. Tumor response was graded in surgically resected specimens by using a three-scale grading system: no response (NR), partial remission (PR) and complete remission (CR). Results : CR was identified in 19 cases (28%), PR in 24 cases (35%), and NR in 26 cases (38%) of 69 cases. p53 protein was expressed in 49 cases (71%), whereas bcl-2 was in 42 cases (61%). The pretreatment Ki-67 labeling index was 65.4+/-3.4%. The tumor response was not associated with any of these markers. Tumors with CR/PR showed a higher AI (0.84+/-.84%/0.66+/-.52%) than that of tumors with NR (0.58+/-0.54%). There was a significant correlation between tumor response and the histologic differentiation (p=0.008) or recurrence (p=0.039). Conclusions : The AI revealed a tendency to increase in tumors with CR/PR, while expressions of p53 and bcl-2, and Ki-67 labeling index had little direct association with tumor response.

Characterization of antigenicity of the outer membrane protein from Edwardsiella tarda / 中国免疫学杂志

Objective:To study the antigenicity of OMP extracted from Edwardsiella tarda.Methods:ELISA, Bactericidal test, Agglutinating test and Western blotting were used for testing the antigenic titers and immunogenicity of OMP.Results:In immunoblotting, by using ATCC15947 OMP antibody, the non pathgenic strains were negative, while all pathogenic strains except Et 122 gave positive results and had OMP bands of 33k, 35k, 38k, and 45k. OMPs of both ATCC 15947 and JEL4 could induce high antibody titers. Further more, the antibodies evoked by OMPs of ATCC 15947 of 33k or 35k could also protected mice to some degree when diluted.Conclusion:The 33k, 35k, 38k, and 45k of OMPs may be protective antigens, and the OMPs of Et could be a candidative component for vaccine.