ABSTRACT
We constructed a recombinant Bacillus Calmette‐Guerin(BCG)‐TSOL18 vaccine of Taenia solium and observed the expression of the TSOL18 gene in BCG .The TSOL18 gene of Taenia solium was obtained from the recombinant plasmid pGEX‐TSOL18 by digestion method and cloned into Escherichia coli (E .coli)‐mycobacterium shuttle plasmid pMV261 to con‐struct the recombinant plasmid pMV261‐TSOL18 of Taenia solium ,and the recombinant plasmid was identified by restriction enzyme digestion ,PCR and DNA sequencing .Then ,the recombinant plasmid was transformed into BCG by electroporation to construct the recombinant BCG‐TSOL18 vaccine of Taenia solium ,and the vaccine was identified by PCR .The expression of the TSOL18 gene in BCG was identified by SDS‐PAGE and Western blot .The 393 bp TSOL18 gene fragment was successfully obtained by restriction enzyme digestion .Restriction enzyme digestion ,PCR and DNA sequencing suggested that the recombi‐nant plasmid pMV261‐TSOL18 of Taenia solium was successfully constructed .PCR confirmed that the recombinant plasmid pMV261‐TSOL18 of Taenia solium was successfully transformed into BCG ,suggesting that the recombinant BCG‐TSOL18 vaccine of Taenia solium was successfully constructed .SDS‐PAGE showed that the relative molecular mass (Mr) of TSOL18 target protein was approximately 14 .7 kD .Results of western blot showed the TSOL18 target protein could be recognized by rabbit antiserum or cysticercosis swine serum .The recombinant BCG‐TSOL18 vaccine of Taenia solium was successfully con‐structed .The TSOL18 gene of Taeniasolium was successfully expressed in BCG and the expressed TSOL18 recombinant pro‐tein had specific antigenicity .This result would lay a foundation for further study of the vaccine .
ABSTRACT
Objective To dynamically observe humoral and cellular immune responses induced in mice by immunization with a recombinant BCG-TSOL18 vaccine of Taenia solium.Methods Totally 80 Kunming mice were divided into 4 groups by using random number table according to body mass, 20 mice in each group: rBCG-TSOL18 intraperitoneal injection group [mice were vaccinated with 5 × 106 colony forming units (CFU) recombinant BCG-TSOL18 vaccine of Taenia solium through intraperitoneal injection], rBCG-TSOL18 intragastric administration group(mice were vaccinated with 4 × 108 CFU recombinant BCG-TSOL18 vaccine of Taenia solium through intragastric administration), BCG control (mice were vaccinated with 5 × 106 CFU BCG through intraperitoneal injection), PBS control (mice were vaccinated with PBS through intraperitoneal injection).Zero, 2, 4, 6 and 8 weeks after immunization, eye blood was collected and serum w as separated.Levels of specific IgG and IgG2a were detected by enzyme linked immunosorbent assay (ELISA).Proliferation level of spleen lymphocytes was detected by CCK-8.Levels of interleukin-2 (IL-2) and IL-4 were determined by ELISA.Results The level of specific IgG in rBCG-TSOL18 intraperitoneal injection group and rBCG-TSOL18 intragastric administration group increased from 2 to 8 weeks, and reached the highest level by the 6th week (0.310 ± 0.022, 0.356 ± 0.026).Compared with 0 week in the same group, BCG and PBS control group of the same time periods (0.054 ± 0.005, 0.057 ± 0.006, 0.093 ± 0.014, 0.085 ± 0.010), there were statistically significant differences (all P ＜ 0.05).The level of specific IgG2a increased from 2 to 8 weeks, and reached the highest level by the 6th week (0.965 ± 0.031, 1.144 ± 0.049).Compared with 0 week in the same group, BCG and PBS control group of the same time periods (0.102 ± 0.014, 0.093 ± 0.012, 0.115 ± 0.012, 0.103 ± 0.013), there were statistically significant differences (all P ＜ 0.05).The proliferation level of spleen lymphocytes increased from 2 to 8 weeks, and reached the highest level by the 6th week (0.524 ± 0.032, 0.755 ± 0.016).Compared with 0 week in the same group, BCG and PBS control group of the same time periods (0.301 ± 0.018, 0.305 ± 0.020, 0.362 ± 0.033, 0.334 ± 0.027), there were statistically significant differences (all P ＜ 0.05).The levels of IL-2 and IL--4 in spleen lymphocyte culture supernatant increased from 2 to 8 weeks and from 4 to 6 weeks, respectively, reached the highest level by the 6th and 4th weeks, respectively [(1 665.41 ± 33.93), (1 785.11 ± 42.39)ng/L and (281.62 ± 23.79), (357.95 ± 42.57)ng/L].Compared with 0 week in the same group, BCG and PBS control group of the same time periods [(1 411.63 ± 20.54), (1 405.12 ± 21.42),(1 455.20 ± 25.03), (1 434.47 ± 17.47)ng/L and (190.17 ± 11.01), (196.96 ± 14.00), (200.51 ± 30.79), (189.64 ±40.90)ng/L], there were statistically significant differences (all P ＜ 0.05).These indexes mentioned above were statistically significantly different (all P ＜ 0.05) between rBCG-TSOL18 intragastric administration group and rBCG-TSOL18 intraperitoneal injection group.Conclusion The recombinant BCG-TSOL18 vaccine of Taenia solium might induce mice to produce humoral and cellular immune responses, and the effect of intragastric administration is better than that of intraperitoneal injection.