Bordetella bronchiseptica antigen enhances the production of Mycoplasma hyopneumoniae antigen-specific immunoglobulin G in mice

We previously demonstrated that Bordetella (B.) bronchiseptica antigen (Ag) showed high immunostimulatory effects on mouse bone marrow cells (BMs) while Mycoplasma (M.) hyopneumoniae Ag showed low effects. The focus of this study was to determine if B. bronchiseptica Ag can enhance the M. hyopneumoniae Ag-specific immune response and whether the host's immune system can recognize both Ags. MTT assay results revealed that each or both Ags did not significantly change BM metabolic activity. Flow cytometry analysis using carboxyfluorescein succinimidyl ester showed that B. bronchiseptica Ag can promote the division of BMs. In cytokine and nitric oxide (NO) assays, B. bronchiseptica Ag boosted production of tumor necrosis factor-alpha in M. hyopneumoniae Ag-treated BMs, and combined treatment with both Ags elevated the level of NO in BMs compared to that from treatment of M. hyopneumoniae Ag alone. Immunoglobulin (Ig)G enzyme-linked immunosorbent assay using the sera of Ag-injected mice clearly indicated that B. bronchiseptica Ag can increase the production of M. hyopneumoniae Ag-specific IgG. This study provided information valuable in the development of M. hyopneumoniae vaccines and showed that B. bronchiseptica Ag can be used both as a vaccine adjuvant and as a vaccine Ag.

Immunogenecity of cytomegalovirus-infected fibroblasts / 细胞与分子免疫学杂志

AIM: To analyze the capability of cytomegaIovirus (CMV)-infected human embryonic lung fibroblasts (HELFs) to induce immune response. METHODS: HELFs were infected with cytomegalovirus and stained with antibody against HLA-A2 molecular, the expression of HLA-A2 was detected by FCM. The infected HELFs were incubated with individual pp65 peptide NLVPMVATV. While the uninfected and unloaded infected HELFs served as control respectively. After PBMC was added to the differently treated HELFs and incubated, the immune response was measured with IFN-γ release as readout. RESULTS: The expression of HLA-A molecular on infected fibroblasts diminished markedly compared with that on the uninfected. The peptides expressed on the infected HELFs together with those pulsed externally induced a stronger response than the infected HELFs alone. CONCLUSION: Although CMV can downregulate the expression of MHC Ⅰ on the infected cells, it can not decrease the capacity of cells to present peptides loaded externally, and therefore still induce immune response to some extent.

Establishment of an in vitro system for testing cytomegalovirus-specific immune response / 中华微生物学和免疫学杂志

Ohiective To establish an in vitro test system for testing CMV specific immune response. Methods Human embryonic lung fibroblasts(HELF)infected with CMV-AD169 and a mutant strain RV-TB40E-4, respectively, were stained with anti-HLA-A * 0201-PE and then measured for the expression of HLA-A * 0201. The infected HELF were incubated with individual pp65 peptide NLVPMVATV and cultured together with PBMC,then intracellular IFN-γ was tested by flow cytometry(FCM). Results The expression of HLA-A * 0201 was markedly suppressed on AD169-infected fibroblasts, while it was not affected on RV-TB40E-4-infected cells. PBMC showing no response to AD169-infected cells responded significantly to RV-TB40E-4-infected cells. The HELF infected with AD169 and loaded with external peptides induced a significantly stronger response which was the sum of the induced response ratios of the infected HELF and the uninfected HELF loaded with peptides. Conclusion CMV-AD169 downregulates the expression of MHC Ⅰ, while it does not decrease the capacity of cells to present external peptides. RV-TB40E-4,a CMV mutant in which the gene of US2-6/US11 has been deleted, does not affect MHC Ⅰ expression, and therefore represents a more suitable tool to explore CMV-specific immune response.