Aerogenic vaccination of mice with Mycobacterium bovis BCG

The course of infection with Mycobacterium bovis BCG Pasteur was followed against time in groups of mice vaccinated by either the aerogenic or subcutaneous route. The generation of acquired protective immunity and immunological memory was determined in each group by adoptive immunisation procedures. In addition, subcutaneously vaccinated mice were tested for their ability to resist an aerogenic challenge with a lethal dose of M. tuberculosis. No overall qualitative differences in the magnitude or longevity of antituberculosis immunity in mice vaccinated by the two procedures were observed. It is concluded that aerogenic vaccination offers no immunological advantage over vaccination by the subcutaneous route.     

Lymphadenitis as a late complication of BCG vaccination

Lymphadenitis is a relatively common complication following intradermal BCG vaccination, and usually occurs 6 to 9 months after injection. However, lymphadenitis following BCG given by the scarification method is rare. We report a case of BCG lymphadenitis occurring 11 and 18 years after vaccination by the scarification method.     

Disseminated Mycobacterium bovis infection after BCG vaccination

The Calmette-Güerin vaccine (BCG) is administered to all the newborns in Iran in order to prevent tuberculosis. Complications of this vaccine are uncommon. We report disseminated BCG disease in 17 patients less than 10 years old. This is a retrospective study of total of 17 cases who were admitted in Children Medical Center Hospital with systemic syndrome compatible with Mycobacterium disease with evidence of histopathologic demonstration of acid-fast bacilli during 1995-2004. Fourteen cases occurred in children younger than 1 year old. Nine patients were female. Ten of the 17 total cases were associated with an immune deficiency including severe combined immunodeficiency, chronic granulomatous disease and cell mediated immune defect. Response to therapy was ineffective and 10 of them (58.8%) died. Disseminated BCG disease is an uncommon but devastating complication of vaccination that should be considered in the appropriate clinical setting. Immune-compromised infants are at greatest risk and they respond poorly to standard therapies.     

Protective efficacy of intranasal vaccination with Mycobacterium bovis BCG against airway Mycobacterium tuberculosis challenge in mice

The effect of route of immunization on the protective efficacy of BCG against tuberculosis has been investigated. Immunoprotection was monitored by evaluating the bacterial burden in the lungs and spleen of mice challenged with Mycobacterium tuberculosis H(37)Rv after BCG immunization by intranasal (i.n.) and subcutaneous (s.c.) routes. Our results showed that as compared to s.c. BCG immunization, intranasal BCG vaccination induces significantly higher immune responses at local level (mediastinal lymph nodes, cervical lymph nodes and lung). Further, i.n. BCG vaccination induced significantly higher reduction in bacterial load in the lungs over s.c. BCG vaccination, whereas, the bacilli load in the spleen was comparable in both the groups. Hence, intranasal vaccination with BCG holds promise for pulmonary tuberculosis.     

Infection of human monocytes with Mycobacterium bovis BCG induces production of CC-chemokines

DESIGN: CC-chemokines are potent leukocyte activators and chemoattractants, which have an important role in granuloma formation, function critical for the immune responses to mycobacterial infection. This study investigated whether infection of human monocytes with Mycobacterium bovis bacillus Calmette-Guérin (BCG) elicits secretion of RANTES, macrophage inflammatory protein (MIP)-1alpha and MIP-1beta. METHODS: RANTES, MIP-1alpha and MIP-1beta synthesis was measured by the presence of protein secretion in the cell culture supernatant as determined by enzyme-linked immunosorbent assay. To investigate the mechanism of M. bovis BCG stimulation of RANTES, we carried out inhibition assays with antibodies to CD40 and we used an intracellular calcium chelator BAPTA-AM. RESULTS: Infection of human monocytes with M. bovis BCG induced RANTES, MIP-1alpha and MIP-1beta secretion in a dose-dependent manner. This stimulation of CC-chemokines production was not attributed to LPS contamination. M. bovis-induced RANTES secretion was dependent upon bacterial uptake and on tumor necrosis factor (TNF)-alpha. Interestingly, the production of RANTES by M. bovis BCG-infected monocytes occurs through a mechanism that requires intracellular calcium and was significantly inhibited (P<0.05) with antibodies to CD40. CONCLUSIONS: These results suggest that the ability of M. bovis BCG to produce CC-chemokines might lead to protection in the acquired immune response of mycobacterial infection and at the same time indicate that M. bovis BCG-induced RANTES secretion is mediated by CD40 and dependent on the intracellular calcium influx.     

Mycobacterium bovis BCG vaccination modulates TNF-alpha production after pulmonary challenge with virulent Mycobacterium tuberculosis in guinea pigs

Tumor necrosis factor-alpha (TNF-alpha) plays critical and opposing roles in the pathogenesis of tuberculosis (TB). We examined the effects of Mycobacterium bovis BCG vaccination on TNF-alpha production in three distinct guinea pig leukocyte populations before and after pulmonary infection with M. tuberculosis H37Rv. Following BCG vaccination alone, and following challenge, bronchoalveolar lavage cells (BALC), resident peritoneal cells (PC), and splenocytes (SPC) were stimulated with purified protein derivative (PPD). Before virulent challenge, BCG vaccination clearly enhanced the ability of BALC, PC and SPC to produce TNF-alpha in response to PPD stimulation ex vivo. Following challenge, the TNF-alpha production of all three leukocyte populations from BCG-vaccinated animals remained relatively constant at pre-challenged levels. In sharp contrast, 5 weeks post-challenge, all three leukocyte populations from unvaccinated animals produced very high amounts of TNF-alpha in response to PPD. Three weeks post-challenge, SPC from one of the unvaccinated animals produced higher levels of TNF-alpha but the others produced lower levels of TNF-alpha than BCG-vaccinated animals. As expected, BCG vaccination reduced the levels of virulent mycobacteria in both the lungs and spleens. Thus, BCG vaccination allows guinea pigs to modulate TNF-alpha levels in conjunction with a reduction in bacillary loads in their tissues.     

Molecular characterization of Mycobacterium bovis BCG: Romanian sub-strain.

The Romanian sub-strain used for BCG vaccine production was characterized by polymorphic GC-rich repetitive sequence (PGRS) restriction profile and IS6110 detection. For comparison, the Pasteur and Moscow Mycobacterium bovis BCG sub-strains, M. bovis AN5, and M. tuberculosis H37Rv were analyzed. The BCG sub-strains showed the same restriction profile for PGRS after Pvu II, BamH I and Sal I digestion. They could be distinguished from the strains M. bovis AN5 and M. tuberculosis H37Rv after Pvu II and Sal I digestion. Sal I can also distinguish between M. bovis AN5 and M. tuberculosis H37Rv. Digestion with Pvu II, Sal I, Sca I, Mlu I and BamH I gave identical profiles of IS6110 hybridization for the Romanian and Pasteur BCG substrains.     

Establishment of a host-vector system in Mycobacterium bovis BCG

The recombinant plasmids, pYT72 and pYT92, were generated from a mycobacterial plasmid, pMSC262, and a Escherichia coli plasmid, pACYC177. These plasmids were capable of replication, and of stable maintainance in Mycobacterium bovis BCG when introduced by electroporation technique. Efficiency of transformation was about 10(4) transformants/micrograms DNA, and was the highest in the phage sensitive mutants (S-10, S-20) isolated from BCG Tokyo strain. We have also isolated transformable mutants from rapidly growing bacterium, M. smegmatis strains Jucho and TMC1533. By isolating deletion mutants from pYT72/92, we could determine the location of replication region of pMSC262 within a 2.3 kb Pst I-Hind III fragment. Using this fragment, we constructed "mini" shuttle plasmid pYT937 (5.9 kb in size) which possesses kanamycin and ampicillin resistance markers and replicates in both E. coli and Mycobacterium. Nucleotide sequence analysis of the replication region revealed that there are 2 potential coding regions which contain more than 200 amino acids. The largest one (ORF1) which codes 311 amino acids, however, lacks Shine-Dalgarno like sequence in the upstream and therefore may not be functional. The other coding region (ORF2) contains 260 amino acids and was preceded by Shine-Dalgarno like sequence. Upstream of the ORF2, there were several repeat sequences which may be important in the plasmid replication. GC content of the 2.3 kb fragment was 69.8%.     

A complication of BCG vaccine: A case of localized cutaneous abscess due to Mycobacterium bovis

The attenuated bacille Calmette-Guérin (BCG) vaccine is administered to prevent tuberculosis. Complications of vaccination are uncommon. A case of cutaneous abscess due to BCG is presented in a 24-year-old woman. The abscess developed at the inoculation site four weeks after vaccination. Routine Gram stain and bacterial cultures of the pus were negative. The auramine stain was positive. Mycobacterial cultures were positive after 14 and 18 days, using the BACTEC 12B bottle and L?wenstein-Jensen media, respectively. The mycobacteria were identified as Mycobacterium bovis, vaccinal strain by high-performance liquid chromatography and DNA probe assays.     

Partial protection against oral challenge with Mycobacterium bovis in ferrets (Mustela furo) following oral vaccination with BCG.

SETTING: Ferrets (Mustela furo) are important wildlife vectors of bovine tuberculosis (TB) in New Zealand. Protective vaccination of ferrets may limit the potential of transmission to livestock. OBJECTIVE: To determine whether orally-delivered Mycobacterium bovis BCG can confer protection against oral challenge with virulent M. bovis. DESIGN: Ten ferrets were vaccinated by feeding measured doses of live BCG, and subsequently challenged with virulent M. bovis via the oral route. Ten non-vaccinated (control) ferrets were similarly challenged. Live body weights and lymphocyte reactivity were monitored longitudinally, and ferrets were killed 20 weeks following challenge. Necropsy, histological examination and bacterial culture of alimentary tract lymphatic tissues were undertaken. RESULTS: There was a significant reduction in the incidence of gross tuberculous lesions among vaccinated ferrets compared to control animals, and fewer vaccinated ferrets had histologically-detectable acid-fast organisms in mesenteric lymph node (LN) tissues. There were significantly fewer vaccinated ferrets with culture-positive retropharyngeal LNs, and the mean bacterial burden was significantly lower for retropharyngeal LNs isolated from vaccinated animals than from controls. CONCLUSION: These results demonstrate that oral BCG vaccination of ferrets can confer partial protection against M. bovis, and suggest that systemic immune responses may be less important in mediating this degree of protection than local immunity.     

Mycobacterium haemophilum infection in a patient with AIDS.

We report the isolation of a nutritionally fastidious mycobacterial species, Mycobacterium haemophilum, from the skin of a patient with AIDS. The diagnosis of the mycobacterial nature of the patient's lesions was complicated by extensive Kaposi's sarcoma. It is recommended that slowly growing fastidious mycobacteria be sought in any patients with unusual skin lesions.     

Immunization of mice with Mycobacterium leprae/Mycobacterium bovis BCG admixtures: modulation of the acquired response to BCG

The generation of acquired immunity to BCG in mice was compared to that in animals receiving an admixture of BCG and killed Mycobacterium leprae. No significant qualitative differences were observed between the two groups in terms of their generation of delayed sensitivity, of protective T cells, and of immunological memory. In addition, the admixture was as effective as BCG in conferring protective immunity against certain nontuberculous mycobacteria, and in one case, that of M. avium 706, significantly augmented protection.     

MPB70, a unique antigen of Mycobacterium bovis BCG

MPB70 is a constituent of Mycobacterium bovis BCG, which accounts for about 10% of the total protein content in the nutrient fluid after culture on Sauton medium. Previous studies of cell-mediated immune reactions have shown that MPB70 is a highly BCG-specific antigen occurring in markedly different concentrations in different substrains of BCG. The present studies were based on the reactivity of MPB70 with antibodies. The precipitate caused by MPB70 was identified in the crossed immunoelectrophoresis pattern of sonicates and concentrated culture fluids of BCG Tokyo. The antigen was quantified by radioimmunoassay inhibition tests on culture fluids standardized on the basis of identical total protein content. It was present in high concentrations in BCG substrains Tokyo, Moreau, Russia, and Sweden, and in M. bovis strain Ravenel. It was also detected in BCG substrains Glaxo, Copenhagen, Tice, and Pasteur, and in M. tuberculosis H37Rv, but in the latter 4 in only 1% or less of the concentration in BCG Tokyo. Six different species of slow- and rapid-growing mycobacteria showed no evidence of cross-reactivity, but a cross-reacting antigen was demonstrated in Nocardia asteroides. The antibody response after immunization of rabbits with BCG Tokyo and BCG Copenhagen was very similar in a polyvalent assay for antibodies reacting with various components of BCG. By contrast, there was a striking difference in anti-MPB70 antibodies, which were rapidly formed in large amounts after immunization with BCG Tokyo and only in very small amounts after immunization with BCG Copenhagen.     

Back pain following instillations of BCG for superficial bladder cancer is not a reactive complication: review of 30 Mycobacterium bovis BCG vertebral osteomyelitis cases

Clinical Rheumatology - Mycobacterium bovis Bacillus Calmette-Guérin (BCG) instillations are used in bladder cancer treatment. Adverse effects can occur. Osteoarticular complications are...