Animals ; Asthma ; immunology ; BCG Vaccine ; immunology ; Humans ; Mycobacterium bovis ; immunology ; T-Lymphocyte Subsets ; immunology

OBJECTIVETo construct a recombinant bacillus Calmette-Guérin vaccine (rBCG) secreting human interferon-alpha 2b (IFN alpha-2b).

METHODSBCG Ag85B signal sequence and IFN alpha-2b gene were amplified from the genome of BCG and of human peripheral blood by polymerase chain reaction (PCR), respectively. IFN alpha-2b gene was cloned in E. coli-BCG shuttle-vector pMV261 to get pMV261-IFN alpha-2b. A new recombinant plasmid pMV261-IFN alpha-2b was constructed by inserting BCG Ag85B signal sequence into pMV261-Ag85B-IFN alpha-2b. Then, BCG was transformed with this recombinant plasmid by electroporation, and designated as rBCG-IFN alpha-2b. The DNA and protein expressions of IFN alpha-2b gene in rBCG were determined by PCR and Western blot respectively. Also the quantity of IFN alpha-2b protein secreted by rBCG in culture supernatants was determined by enzyme linked immunosorbent assay (ELISA).

RESULTSBy partial nucleotide sequencing, the DNA sequences of human IFN alpha-2b and BCG Ag85B were consistent with that in the Gene Bank, and were correctly inserted into the shuttle expression vector pMV261 to construct recombinant plasmid pMV261-Ag85B-IFN alpha-2b. BCG was successfully transformed with this recombinant plasmid by electroporation and the recombinant BCG (rBCG-IFN alpha-2b) was capable of synthesizing and secreting cytokine IFN alpha-2b. The concentration of IFN alpha-2b in culture supernatants was quantified by ELISA and calculated to be approximately 301.45 pg/ml.

CONCLUSIONSRecombinant BCG secreting human IFN alpha-2b (rBCG-IFN alpha-2b) was constructed successfully and the specific IFN alpha-2b protein can be expressed highly and steadily by rBCG vaccine.

BCG Vaccine ; genetics ; immunology ; metabolism ; Gene Expression ; Genetic Vectors ; Humans ; Interferon-alpha ; genetics ; metabolism ; Plasmids ; genetics ; Recombinant Proteins ; Transformation, Bacterial

OBJECTIVEThe impact of dendritic cells (DCs) and regulatory T cells (Tr) on the pathogenesis of asthma have been investigated over the past decades. As the professional antigen presenting cells, DCs not only prime immune response directing Th0 cells toward different T subtypes but also induce immune tolerance. As an immunoregulator, Bacillus Calmette-Guerin (BCG) has potential to be applied in allergic diseases such as asthma for prevention. Previous study showed that neonatal BCG vaccination could induce Th1/Tr1 development in mice in vivo. To further identify the mechanism of neonatal BCG vaccination on T cell subsets differentiation, the present study was designed to investigate the impact of BCG vaccination on splenic DCs development in neonatal mice.

METHODSNeonatal specific pathogen free (SPF) BALB/c mice (2-3 days) were divided into intraperitoneal BCG-treated group, subcutaneous BCG-treated group and control group; simultaneously adult SPF BALB/c mice (6-8 weeks) were divided into intraperitoneal BCG-treated and control group. The BCG-treated mice were inoculated with 1 x 10(5) CFU BCG, the mice in control group were not inoculated with any vaccine. Four weeks post BCG vaccination, spleen cells were isolated. With flow cytometry, subtype and maturity of splenic DCs were analysed. Moreover, cells were further separated into mononuclear cell by Ficoll solution. The mononuclear cells were stimulated by 1 microg/ml lipopolysaccharide (LPS) for 18 or 10(5) CFU /ml BCG for 48 hours at 37 degrees C in a humidified atmosphere containing 5% CO2 and cytokines concentration was detected by ELISA.

RESULTS(1) CD11c(+) CD8alpha(+) and CD11c(+) CD8alpha(-) DCs were found in spleen cells of the BALB/c mice. In comparison with the control group, the percent of CD11c(+) CD8alpha(-) DCs in intraperitoneal BCG group significantly declined (P < 0.01) and that of CD11c(+) CD8alpha(+) DCs significantly increased (P < 0.01), there were no significant difference in DC subtypes between intraperitoneal and subcutaneous BCG-vaccinated mice. In contrast, the percent of CD11c(+) CD8alpha(-)DCs markedly increased (P < 0.01) and that of CD11c(+) CD8alpha(+)DCs noticeably reduced (P < 0.01) in adult BCG-vaccinated mice. The percent of CD11c(+)CD8alpha(-)DC was significantly higher and that of CD11c(+) CD8alpha(+)DC was significantly lower in adult-vaccinated BALB/c mice than that of neonatal-vaccinated ones. (2) The expression of costimulatory molecules CD40 on CD11c(+) CD8alpha(-) DCs and CD86 on CD11c(+) CD8alpha(+) DCs in neonatal BCG-treated BALB/c mice was higher than the controls. There were no significant difference in expression of costimulatory molecules on DC between neonatal BCG-vaccinated mice. Compared with the control group, expression of CD40 and MHC-II molecules on CD11c(+) CD8alpha(-) and CD11c(+) CD8alpha(+)DC was significantly higher and that of CD86 was significantly lower in adult BCG-vaccinated mice. The expression of costimulatory molecules on DC had no significant difference between neonatal and adult BCG vaccinated BALB/c mice. (3) As compared with the control mice, concentration of IL-12p70 induced by LPS and IL-10 induced by BCG in vitro from spleen cells culture supernatant was noticeably elevated (P < 0.05) in neonatal BCG-treated BALB/c mice, but that of IL-6 did not change by LPS or BCG stimulation.

CONCLUSION(1) By up-regulating splenic CD8alpha(+)DCs and inducing IL-12p70 and IL-10 production in BALB/c mice, neonatal BCG vaccination promoted Th1/Tr1 development. (2) The effect of BCG vaccination on DC was different between neonates and adult BALB/c mice.

Animals ; Animals, Newborn ; BCG Vaccine ; immunology ; Cell Differentiation ; Cells, Cultured ; Dendritic Cells ; cytology ; immunology ; metabolism ; Immunophenotyping ; Mice ; Mice, Inbred BALB C ; Spleen ; cytology ; immunology ; metabolism

OBJECTIVEAlmost every neonate receives Bacillus Calmette-Guerin (BCG) vaccination in China. The authors' previous study showed that BCG promoted cord blood monocyte-derived dendritic cells maturation and induced high level of interleukin (IL)-10, medium level of interferon (IFN)-gamma, but low level of IL-4 production by cord naive T cells. The experiments in the present study were designed to explore the effects of neonatal BCG vaccination on immune functional development of splenic T cells in mice in vivo.

METHODSNeonatal BALB/c mice were inoculated with BCG intraperiotoneally. Four weeks later, spleen cells of mice were isolated and surface molecular markers of CD4, CD25 and CD44 and intracellular IFN-gamma, IL-10, and IL-4 in CD3(+) T cells were detected by flow cytometry. Furthermore, mRNA expression of transcription factor T-bet, Foxp3 and GATA-3 were analyzed by RT-PCR.

RESULTSThe percentage of total CD4(+) T cells decreased [(23.50 +/- 2.59)% vs. (47.38 +/- 10.41)%, P < 0.01] but the percentage of CD25(+) [(24.92 +/- 2.74)% vs. (20.27 +/- 2.85)%, P < 0.05] and CD44(+) [(89.29 +/- 2.56)% vs. (82.98 +/- 5.51)%, P < 0.05] T cells in CD4(+) T cells was higher in BCG-vaccinated mice than that in controls. Meanwhile, the percentage of IFN-gamma positive [(6.52 +/- 2.40)% vs. (3.13 +/- 2.03)%, P < 0.05] and IL-10 positive [(14.81 +/- 3.65)% vs. (10.90 +/- 1.61)%, P < 0.05] but not IL-4 positive [(1.17 +/- 0.46)% vs (1.51 +/- 0.75)%, P > 0.05] cells in CD3(+) T cells of BCG-vaccinated mice was significantly higher than that of non-BCG-vaccinated mice. In comparison with BCG-naive mice, T-bet was significantly high in BCG-vaccinated mice [T-bet/beta-actin 0.44 +/- 0.11 vs. 0.28 +/- 0.06, P < 0.05], but there was no significant difference in GATA-3 [GATA-3/beta-actin 0.46 +/- 0.08 vs. 0.50 +/- 0.10,P > 0.05] and Foxp3 [Foxp3/beta-actin vs. 0.27 +/- 0.11 and 0.30 +/- 0.16, P > 0.05] mRNA expression between the two groups.

CONCLUSIONNeonatal BCG vaccination could induce strong Th1 but weak Th2 response as reported previously. Though neonatal BCG vaccination was not capable of inducing CD4(+)CD25(+) regulatory T cell response with Foxp3 expression, it caused increase of IL-10(+) CD3(+) cells which might represent some regulatory T cells producing IL-10.

Animals ; Animals, Newborn ; BCG Vaccine ; immunology ; GATA3 Transcription Factor ; genetics ; Interferon-gamma ; biosynthesis ; Interleukin-10 ; biosynthesis ; Mice ; Mice, Inbred BALB C ; Spleen ; immunology ; T-Lymphocytes ; immunology ; Vaccination

This study was purposed to investigate the effect of bacillus calmette-guerin (BCG) on the expansion of human dendritic cells (DC) from peripheral blood of pediatric patients with leukemia in vitro. The experiment was divi-ded into two groups: the control and the test group, and the latter group was divided into 3 subgroups: BCG (only BCG), GTI (GM-CSF, TNF-α, IL-4) and GTIB (GM-CSF, TNF-α, IL-4 plus BCG). On day 9 of culture the DCs were counted in each groups, the phenotypes of DC were determined by flow cytometry and these DC were stained with Wright-Giemsa for observation and photography under microscopy. The results showed that the test groups all obtained a certain amount of typical DC; the number of DC in the BCG subgroup is lower than that in the GTI and GTIB subgroups (t=4.20; 6.36, p<0.01); there was no significant difference between the GTI and the GTIB subgroups (t=2.25; p>0.05). The rate of CD1a+ in the BCG subgroup was obviously higher than that in the control group (t=3.04, p<0.05), but was lower than that in the GTI and the GTIB subgroups (t=2.79, 6.41, p<0.05), there was no significant difference between the GTI and the GTIB subgroups (t=0.65, p>0.05). The rate of HLA-DR+, CD83+ in the BCG group was higher than that in the control group (t=4.77, 4.15; p<0.05), but lower than that in the GTI and the GTIB subgroups (t=6.65, 3.19; p<0.05). The rate of HLA-DR+, CD83+ in the GTI subgroup was lower than that in the GTIB subgroup (t=5.64, 2.98; p<0.05). It is concluded that BCG not only promotes the proliferation of DC derived from human peripheral blood of leukemia patients in vitro, but also cooperates with rhGM-CSF, rhTNF-α and rhIL-4 in promoting the maturation of DCs.
BCG Vaccine ; immunology ; pharmacology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Child ; Dendritic Cells ; cytology ; drug effects ; Humans ; Leukemia ; immunology ; Mycobacterium bovis ; immunology

Disseminated mycobacterial infection after bacillus Calmette-Guerin (BCG)vaccination is a very rare disorder, occurring mostly in patients with immunologic deficiency. We report a case of disseminated BCG infection in a 16-month-old girl with severe combined immunodeficiency. Plain radiographs showed multiple osteolytic lesions in the femora, tibiae, humerus, and phalanges. Abdominal sonography and CT scanning revealed multiple nodules in the spleen, and porto-caval lymphadenopathy.
*BCG Vaccine ; Case Report ; Female ; Human ; Infant ; Mycobacterium bovis ; Severe Combined Immunodeficiency/*immunology ; Tomography, X-Ray Computed ; Tuberculosis/*immunology/radiography/ultrasonography

Disseminated mycobacterial infection after bacillus Calmette-Guerin (BCG)vaccination is a very rare disorder, occurring mostly in patients with immunologic deficiency. We report a case of disseminated BCG infection in a 16-month-old girl with severe combined immunodeficiency. Plain radiographs showed multiple osteolytic lesions in the femora, tibiae, humerus, and phalanges. Abdominal sonography and CT scanning revealed multiple nodules in the spleen, and porto-caval lymphadenopathy.
*BCG Vaccine ; Case Report ; Female ; Human ; Infant ; Mycobacterium bovis ; Severe Combined Immunodeficiency/*immunology ; Tomography, X-Ray Computed ; Tuberculosis/*immunology/radiography/ultrasonography

OBJECTIVETo study the prevalence of skin positivity to purified protein derivative (PPD) in human immunodeficiency virus (HIV)-infected patients in Hong Kong.

METHODSConsecutive clients of an HIV clinic were administered the PPD test and 2 units of PPD-RT23 were used. The area of induration was then measured in 48 to 72 h. Results were related to patient characteristics and HIV-related parameters.

RESULTSEight (17.0%) out of 47 clients tested positive to the administration of 2 units of PPD-RT23. If the cutoff were raised to 10 mm according to current practice, only two (4.3%) would test positive.

CONCLUSIONThe prevalence of PPD positivity in HIV-infected patients in Hong Kong is 17%, when a cutoff of 5 mm is used. This figure may form the basis for further studies on the utility of isoniazid preventive therapy in this group of patients.

Adult ; Aged ; BCG Vaccine ; immunology ; Female ; HIV Infections ; complications ; immunology ; Humans ; Isoniazid ; therapeutic use ; Male ; Middle Aged ; Prevalence ; Tuberculin Test ; Tuberculosis ; prevention & control

OBJECTIVEPrevious studies have shown that bacillus calmette-guerin (BCG) can deviate TH2 response toward TH1 response, resulting in a suppressive effect on the development of asthma/atopy. This study examined the effect of BCG treatment on regulatory T cells in asthmatic mice to investigate the possible mechanism.

METHODSKunming mice were sensitized and challenged with ovalbumin (OVA) to establish asthmatic models. Asthmatic mice were injected intradermally with BCG five days before and after sensitization. After 24 hrs of last challenge, bronchoaveolar lavage fluid (BALF) and peripheral blood were collected . The total cells and eosinophils were counted in the BALF. The percentage of CD4(+) CD25(+) in peripheral blood was detected with flow cytometry. Single spleen cell suspension was prepared and cultured in 1640 medium for 48 hrs and then the cytokine IL-10 level in the supernatant was determined using ELISA. The mice which were challenged with normal saline were used as the Normal control group.

RESULTSThe number of total cells and eosinophils in BALF in asthmatic mice [(27.27 +/- 5.36) x 10(7)/L and (6.59 +/- 1.32) x 10(7)/L respectively] were more than in the Normal control group [(1.52 +/- 0.36) x 10(7)/L and zero respectively] (P < 0.01). The number of total cells and eosinophils in BALF in asthmatic mice were reduced after BCG treatment [(13.71 +/- 3.17) x 10(7)/L and (1.43 +/- 0.37) x 10(7)/L respectively] (P < 0.01). The percentage of CD4(+) CD25(+) in peripheral blood of asthmatic mice [(11.59 +/- 1.33)%] was noticeably lower than that of the Control group [(13.66 +/- 1.68)%] (P < 0.01), but increased significantly in asthmatic mice after BCG treatment [(14.40 +/- 2.70)%] (P < 0.05). The IL-10 level in spleen cell supernatant in the BCG-treated group (7.79 +/- 1.34 pg/mL) also increased compared with that in the untreated asthmatic mice (5.54 +/- 0.66 pg/mL) (P < 0.01).

CONCLUSIONSBCG can markedly inhibit the airway inflammation in asthmatic mice possibly by promoting the production of regulatory T cells.

Animals ; Asthma ; immunology ; therapy ; BCG Vaccine ; therapeutic use ; Bronchoalveolar Lavage Fluid ; cytology ; Interleukin-10 ; analysis ; physiology ; Male ; Mice ; T-Lymphocytes, Regulatory ; immunology ; Toll-Like Receptor 2 ; physiology

OBJECTIVETo evaluate the clinical significance of using T cell responses to three RD1-encoded gene products for diagnosis of mycobacterium tuberculosis (MTB) infection.

METHODSWe used ex vivo gamma-interferon enzyme-linked immunospot assays to test T cell responses to three novel gene products encoded by RD1 (Rv3873, Rv3878, and Rv3879c) in 49 patients (TB group) who were bacteriologically confirmed by positive cultures for MTB and 38 healthy BCG-vaccinated donors (control group). Forty-nine overlapping peptides were tested in all participants.

RESULTSThe T cell response rates to Rv3873, Rv3878, and Rv3879c were 53% (95% CI: 39%-67%), 35% (95% CI: 22%-48%), and 45% (95% CI: 31%-57%), respectively, in the TB group and were 7.9%, 2.6%, and 2.6%, respectively, in the control group.

CONCLUSIONRv3879c peptides can be candidates for inclusion in new T cell-based tests for MTB infection.

Adult ; Antigens, Bacterial ; immunology ; BCG Vaccine ; immunology ; Bacterial Proteins ; immunology ; Female ; Humans ; Immunoassay ; Interferon-gamma ; immunology ; Male ; Middle Aged ; Mycobacterium tuberculosis ; immunology ; T-Lymphocytes ; immunology ; Tuberculosis ; diagnosis ; immunology ; Young Adult