This study constructed a porcine reproductive and respiratory syndrome virus(PRRSV)NADC30-like strain GP3 recombinant adenovirus vector vaccine through in vitro homologous re-combination to explore its immunological efficacy evaluation at the mouse level.Using type 5 ade-novirus as a vector,a recombinant adenovirus expressing PRRSV GP3 protein was prepared and i-dentified in vitro by fluorescence observation,PCR,and Western blot analysis.Immunize mice with recombinant adenovirus and detect humoral and cellular immune responses induced by recombi-nant adenovirus using indirect ELISA and ELISpot methods.The recombinant adenovirus rAdGP3 was identified by enzyme digestion,PCR,fluorescence and Western blot,indicating that the recom-binant adenovirus rAdGP3 was successfully constructed and packaged.After immunizing mice,spe-cific antibodies and neutralizing antibodies were produced,indicating that the recombinant adenovi-rus could elicit strong humoral immunity.ELISpot and lymphocyte proliferation assays showed that the recombinant adenovirus vaccine could stimulate the secretion of IFN-γ-specific T lymphocytes and induce the proliferation of lymphocytes,indicating that the recombinant adenovi-rus could enhance the level of cellular immune response.In this study,rAdGP3 recombinant adeno-virus was successfully constructed and had good immunogenicity at the mouse level,which provid-ed a reference for the development of novel PRRSV vaccines.

This study constructed a porcine reproductive and respiratory syndrome virus(PRRSV)NADC30-like strain GP3 recombinant adenovirus vector vaccine through in vitro homologous re-combination to explore its immunological efficacy evaluation at the mouse level.Using type 5 ade-novirus as a vector,a recombinant adenovirus expressing PRRSV GP3 protein was prepared and i-dentified in vitro by fluorescence observation,PCR,and Western blot analysis.Immunize mice with recombinant adenovirus and detect humoral and cellular immune responses induced by recombi-nant adenovirus using indirect ELISA and ELISpot methods.The recombinant adenovirus rAdGP3 was identified by enzyme digestion,PCR,fluorescence and Western blot,indicating that the recom-binant adenovirus rAdGP3 was successfully constructed and packaged.After immunizing mice,spe-cific antibodies and neutralizing antibodies were produced,indicating that the recombinant adenovi-rus could elicit strong humoral immunity.ELISpot and lymphocyte proliferation assays showed that the recombinant adenovirus vaccine could stimulate the secretion of IFN-γ-specific T lymphocytes and induce the proliferation of lymphocytes,indicating that the recombinant adenovi-rus could enhance the level of cellular immune response.In this study,rAdGP3 recombinant adeno-virus was successfully constructed and had good immunogenicity at the mouse level,which provid-ed a reference for the development of novel PRRSV vaccines.

OBJECTIVETo observe the ultrastructures of rat alveolar type II cells and change of composition of phospholipid(PL) and content of protein in pulmonary surfactant(PS), to investigate the relation between change in composition of PL and activity of alveolar type II cells.

METHODSThe rats lung injury models were made by intratracheally instilling bleomycin(BLM) (4 mg/ml, 5 mg/kg). 28 rats were divided into four groups: 3-day group, 7-day group, 14-day group and 28-day group. Preparations of each group were stained histochemically and examined by electron microscope, content of PL in BALF, composition of PL and content of protein of each group were determined respectively.

RESULTS(1) Rats lungs in experimental groups were found that PS lost continuously, appeared homogenous and chorionic, dropped in the pulmonary alveolies. 3-day group was more apparent. Ruthenium red attaching on pulmonary surfactant was thicker in 3-day group, and the colour deeper, no difference in 7-day group and 14-day group, thinner in 28-day group. Content of PL in PS of BALF was increasing. Content of phosphatidylglycerol(PG) increased in 3-day group, decreased in 7-day, 14-day and 28-day group. The change of content of phosphatidylinositol(PI) was reversed. (2) Alveolar type II cells degenerated, necrotized, even disintegrated in 3-day group and 7-day group. 3-day group was more apparent. Proliferations of alveolar type II cells were found in each group, 7-day group was more apparent. We found that type II cells transformed to type I cells in 14-day group, extended and attached on bare basement membrane. Content of protein in PS was the highest in 3-day group, almost equal to the content of the control group in 28-day group.

CONCLUSIONMorphologic change and alternation of quality and quantity of PS after bleomycin-induced pulmonary injures specifically reflect the activity of alveolar type II cells. Measuring content of PL in BALF is one of simple and feasible method judging activity of alveolar type II cells when lungs of the rats are injured early by bleomycin.

Animals ; Antibiotics, Antineoplastic ; toxicity ; Bleomycin ; toxicity ; Bronchoalveolar Lavage Fluid ; chemistry ; Lung ; drug effects ; pathology ; ultrastructure ; Pulmonary Alveoli ; chemistry ; Pulmonary Surfactants ; analysis ; Rats