Yamakagashi, Rhabdophis tigrinus, is a natricine snake widely distributed in eastern Asia. Severe bite cases, some with fatal outcomes, occur regularly in Japan. Because previous production of R.
View Article and Find Full Text PDFTo develop an efficient nasal influenza vaccine, influenza A and B virus HA with rCTB as a mucosal adjuvant were administered to mice intranasally. Serum anti-HA IgG and IgA antibody responses for both HA vaccines were significantly increased in the presence of rCTB. Higher HI and neutralizing antibody titers and higher mucosal IgA antibody responses in the respiratory tract were detected when rCTB was added than without rCTB.
View Article and Find Full Text PDFThe mamushi (Gloydius blomhoffii) snakes that inhabit Japan, Korea, and China produce venoms with similar serological characters to each other. Individual domestic standard mamushi antivenoms have been used for national quality control (potency testing) of mamushi antivenom products in these countries, because of the lack of an international standard material authorized by the World Health Organization. This precludes comparison of the results of product potency testing among countries.
View Article and Find Full Text PDFRecombinant cholera toxin B subunit (rCTB) which is produced by Bacillus brevis carrying pNU212-CTB acts as a mucosal adjuvant capable of enhancing host immune responses specific to unrelated, mucosally co-administered vaccine antigens. When mice were administered intranasally with diphtheria-pertussis-tetanus (DPT) combination vaccine consisting of diphtheria toxoid (DTd), tetanus toxoid (TTd), pertussis toxoid (PTd), and formalin-treated filamentous hemagglutinin (fFHA), the presence of rCTB elevated constantly high values of DTd- and TTd-specific serum ELISA IgG antibody titres, and protective levels of diphtheria and tetanus toxin-neutralizing antibodies but the absence of rCTB did not. Moreover, the addition of rCTB protected all mice against tetanic symptoms and deaths.
View Article and Find Full Text PDFRecombinant cholera toxin B subunit (rCTB) is a safe and potent mucosal adjuvant. To gain insight into the mechanism underlying the adjuvant effect of rCTB, the effects of rCTB on cell-mediated immune responses of mice and guinea pigs were examined after intranasal administration of Mycobacterium bovis -bacillus Calmette-Guérin (BCG) with and without rCTB. Delayed-type hypersensitivity, for skin reactions in guinea pigs and for footpad swelling reactions in mice, to purified protein derivative (PPD) were enhanced by intranasal co-administration of BCG and rCTB, as compared to giving BCG alone to these animals.
View Article and Find Full Text PDFVaccination via a mucosal route is a very attractive means for immunization, because both local and systemic immune responses are inducible and vaccines can be administered easily and safely from infants to elderly persons. For developing widely applicable mucosal vaccines using recombinant cholera toxin B subunit (rCTB) as a safe adjuvant, we examined whether frequent nasal administrations of rCTB-containing same and different vaccines could induce antigen-specific immune responses without induction of systemic tolerance and suppression by pre-existing anti-rCTB immunity. Ten repetitive nasal administrations to mice of tetanus toxoid (TT) + rCTB or diphtheria toxoid (DT) + rCTB raised and maintained high levels of antigen- and rCTB-specific serum IgG including high levels of tetanus/diphtheria antitoxin titres and raised nasal, salivary, lung, vaginal and fecal secreted IgA, suggesting that the regimen did not induce systemic tolerance to TT/DT and rCTB.
View Article and Find Full Text PDFTo investigate the possibility of intranasal immunization with an acellular pertussis vaccine, groups of mice were administered intranasally with aluminium-non-adsorbed pertussis toxoid (PTd; 0.5 or 5 microg) and formalin-treated filamentous hemagglutinin (fFHA; 5 microg) with and without recombinant cholera toxin B subunit (rCTB; 10 microg) as a mucosal adjuvant. At a low concentration of PTd, the following things became clear: (1) earlier and higher elevation of serum anti-PTd and anti-FHA IgG antibody titres in the presence of rCTB than in its absence, (2) higher serum anti-PTd and anti-FHA IgG antibody titres than 200 and 100 ELISA units ml(-1) (EU ml(-1)) in all mice, respectively, in the presence of rCTB, which were obtained by calibration against a reference anti-pertussis mouse serum, and (3) in an intranasal challenge experiment with Bordetella pertussis, slightly more rapid elimination of the bacteria from the lungs of mice intranasally immunized in the presence of rCTB, suggesting the effectiveness of rCTB as a mucosal adjuvant.
View Article and Find Full Text PDFBackground: We have previously reported that intraperitoneal injection with OVA-liposome conjugates induces OVA-specific and IgE-selective unresponsiveness in mice.
Methods: In the present study, the effects of oral pre-treatment with OVA-liposome conjugates or with plain OVA solution on anti-OVA IgG antibody production were investigated in mice after subsequent immunization with alum-adsorbed OVA. Control mice received only the immunization.
Recombinant cholera toxin B subunit (rCTB) is a safe and potent mucosal adjuvant. As a clue to the mechanism of the adjuvant effect of rCTB, the profile of cytokines secreted in vitro by the mouse peritoneal macrophage (Mphi) treated with rCTB was examined. IL-1beta secretion, intracellular production, and expression of its mRNA of LPS-stimulated Mphi was greatly enhanced by treatment with rCTB.
View Article and Find Full Text PDF