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Fulltext Survival and Intra-Nuclear Trafficking of Burkholderia pseudomallei: Strategies of Evasion from Immune Surveillance?

Vadivelu J, Vellasamy KM, Thimma J, Mariappan V, Kang WT, Choh LC, et al.

PLoS Negl Trop Dis, 2017 01;11(1):e0005241.
PMID: 28045926 DOI: 10.1371/journal.pntd.0005241

BACKGROUND: During infection, successful bacterial clearance is achieved via the host immune system acting in conjunction with appropriate antibiotic therapy. However, it still remains a tip of the iceberg as to where persistent pathogens namely, Burkholderia pseudomallei (B. pseudomallei) reside/hide to escape from host immune sensors and antimicrobial pressure.
METHODS: We used transmission electron microscopy (TEM) to investigate post-mortem tissue sections of patients with clinical melioidosis to identify the localisation of a recently identified gut microbiome, B. pseudomallei within host cells. The intranuclear presence of B. pseudomallei was confirmed using transmission electron microscopy (TEM) of experimentally infected guinea pig spleen tissues and Live Z-stack, and ImageJ analysis of fluorescence microscopy analysis of in vitro infection of A549 human lung epithelial cells.
RESULTS: TEM investigations revealed intranuclear localization of B. pseudomallei in cells of infected human lung and guinea pig spleen tissues. We also found that B. pseudomallei induced actin polymerization following infection of A549 human lung epithelial cells. Infected A549 lung epithelial cells using 3D-Laser scanning confocal microscopy (LSCM) and immunofluorescence microscopy confirmed the intranuclear localization of B. pseudomallei.
CONCLUSION: B. pseudomallei was found within the nuclear compartment of host cells. The nucleus may play a role as an occult or transient niche for persistence of intracellular pathogens, potentially leading to recurrrent episodes or recrudescence of infection.

Matched MeSH terms: Spleen/microbiology
[Results of examining wild monkeys for the presence of smallpox antibodies and smallpox group viruses]

Marennikova SS, Shelukhina EM, Shenkman LS, Mal'tseva NN, Matsevich GR

Vopr. Virusol., 1975 May-Jun.
PMID: 169629

The results of examinations of sera, blood and organs of different species of monkeys from some Asian and African countries for the presence of antibody to smallpox and viruses of the smallpox group. Significant titers of smallpox antibodies (antihemagglutinins virus-neutralizing and, in some cases, precipitating antibody) were found in a considerable number of monkeys shot near foci with human cases (Equatorial province of Zair Republic). In the same monkeys kidney tissues yielded 3 isolates of smallpox virus group two of which were indistinguishable in the laboratory tests from variola virus. On the basis of these data it is concluded that smallpox viruses circulate among wildlife monkeys in some areas of Equatorial Africa. Further studies along these lines are necessary.

Matched MeSH terms: Spleen/microbiology
Melioidosis mimicking miliary tuberculosis

Tan RZ, Mohd Nor F, Shafie S, Tan LJ

Forensic Sci Med Pathol, 2019 03;15(1):151-154.
PMID: 30293222 DOI: 10.1007/s12024-018-0026-3

Melioidosis is an infectious disease caused by Burkholderia pseudomallei, a gram-negative intracellular bacillus. Tuberculosis, also an infectious disease, is caused by Mycobacterium tuberculosis, an acid fast bacillus. In both diseases, patients commonly present with fever and respiratory symptoms due to sepsis which might lead to respiratory failure or sudden death if left untreated. Not only are these two entities similar in clinical presentation, but the autopsy findings may mimic each other, giving rise to difficulties in determining the cause of death. We report a case of melioidosis and compare it to a typical case of miliary tuberculosis. Similarities between the cases on gross and histopathological examinations are discussed. In such circumstances, microbiological culture of bodily fluids and internal organs should be performed to ascertain the correct cause of death.

Matched MeSH terms: Spleen/microbiology
Recent advances in experimental leprosy

Rees RJ

Bibl Tuberc, 1970;26:189-232.
PMID: 4244234
Matched MeSH terms: Spleen/microbiology
Fulltext Isolation and molecular characterization of Brucella melitensis from seropositive goats in Peninsula Malaysia

Bamaiyi PH, Hassan L, Khairani-Bejo S, Zainal Abidin M, Ramlan M, Krishnan N, et al.

Trop Biomed, 2012 Dec;29(4):513-8.
PMID: 23202595

A study was carried out to isolate Brucella melitensis using established bacteriological and PCR techniques in Brucella seropositive goats in farms in Selangor, Negeri Sembilan, Melaka and Pulau Pinang. Brucella melitensis was isolated from 7 of 134 reactors with the highest isolation from the vaginal swabs (57.14%) followed by the spleen (28.57%), uterine fluid (14.29%). No Brucella was isolated from the lymph nodes. PCR confirmed all the seven isolates as B. melitensis and isolates were phylogenetically related to other isolates from India, Iran, and Israel but most closely related to isolates from Singapore.

Matched MeSH terms: Spleen/microbiology
Fulltext Experimental Phage Therapy for Burkholderia pseudomallei Infection

Guang-Han O, Leang-Chung C, Vellasamy KM, Mariappan V, Li-Yen C, Vadivelu J

PLoS One, 2016;11(7):e0158213.
PMID: 27387381 DOI: 10.1371/journal.pone.0158213

Burkholderia pseudomallei is an intracellular Gram-negative bacterial pathogen intrinsically resistant to a variety of antibiotics. Phages have been developed for use as an alternative treatment therapy, particularly for bacterial infections that do not respond to conventional antibiotics. In this study, we investigated the use of phages to treat cells infected with B. pseudomallei. Phage C34 isolated from seawater was purified and characterised on the basis of its host range and morphology using transmission electron microscopy (TEM). Phage C34 was able to lyse 39.5% of B. pseudomallei clinical strains. Due to the presence of contractile tail, phage C34 is classified as a member of the family Myoviridae, a tailed double-stranded DNA virus. When 2 × 105 A549 cells were exposed to 2 × 107 PFU of phage C34, 24 hours prior to infection with 2 × 106 CFU of B. pseudomallei, it was found that the survivability of the cells increased to 41.6 ± 6.8% as compared to 22.8 ± 6.0% in untreated control. Additionally, application of phage successfully rescued 33.3% of mice infected with B. pseudomallei and significantly reduced the bacterial load in the spleen of the phage-treated mice. These findings indicate that phage can be a potential antimicrobial agent for B. pseudomallei infections.

Matched MeSH terms: Spleen/microbiology
Fulltext Computed tomography of focal splenic lesions in patients presenting with fever

Joazlina ZY, Wastie ML, Ariffin N

Singapore Med J, 2006 Jan;47(1):37-41.
PMID: 16397719

INTRODUCTION: There is an awareness of the increased incidence of splenic abscess in Southeast Asia giving rise to unexplained fever. This study looks at the role of computed tomography (CT) in evaluating focal splenic lesions in patients presenting with fever.
METHODS: 37 patients presenting with fever of unknown origin underwent CT and this study retrospectively analyses the findings in these patients. 13 patients also had associated abdominal pain. Patients with conditions at high risk for splenic infection include: diabetes mellitus in ten patients, leukaemia in seven patients, human immunodeficiency virus infection in five patients, intravenous drug abuse in six patients, and steroid therapy in two patients. No risk factors could be identified in seven patients.
RESULTS: Splenic abscess was diagnosed in 28 patients. A range of infecting organisms was isolated but the most frequent were Staphylococcus aureus (eight), tuberculosis (four), Streptococcus (four), fungal (four) and melioidosis (four). No infecting organism could be identified in ten cases though in patients with leukaemia with multiple low attenuation areas, the cause was presumed to be fungal. Six patients were diagnosed to have splenic infarcts though differentiation from splenic abscess could be difficult; these patients were treated for an abscess and all had endocarditis. Three patients were subsequently diagnosed with lymphoma. Percutaneous abscess drainage was performed in five patients and splenectomy was carried out in six patients.
CONCLUSION: CT proved to be very useful as it not only revealed the size and extent of any splenic abnormality but it assisted with guidance for percutaneous drainage, determined the site for biopsy, and provided follow-up after treatment.

Matched MeSH terms: Spleen/microbiology
Fulltext Delayed activation of host innate immune pathways in streptozotocin-induced diabetic hosts leads to more severe disease during infection with Burkholderia pseudomallei

Chin CY, Monack DM, Nathan S

Immunology, 2012 Apr;135(4):312-32.
PMID: 22136109 DOI: 10.1111/j.1365-2567.2011.03544.x

Diabetes mellitus is a predisposing factor of melioidosis, contributing to higher mortality rates in diabetics infected with Burkholderia pseudomallei. To investigate how diabetes alters the inflammatory response, we established a streptozotocin (STZ) -induced diabetic murine acute-phase melioidosis model. Viable B. pseudomallei cells were consistently detected in the blood, liver and spleen during the 42-hr course of infection but the hyperglycaemic environment did not increase the bacterial burden. However, after 24 hr, granulocyte counts increased in response to infection, whereas blood glucose concentrations decreased over the course of infection. A genome-wide expression analysis of the STZ-diabetic murine acute melioidosis liver identified ~1000 genes whose expression was altered in the STZ-diabetic mice. The STZ-diabetic host transcriptional response was compared with the normoglycaemic host transcriptional response recently reported by our group. The microarray data suggest that the presence of elevated glucose levels impairs the host innate immune system by delaying the identification and recognition of B. pseudomallei surface structures. Consequently, the host is unable to activate the appropriate innate immune response over time, which may explain the increased susceptibility to melioidosis in the STZ-diabetic host. Nevertheless, a general 'alarm signal' of infection as well as defence programmes are still triggered by the STZ-diabetic host, although only 24 hr after infection. In summary, this study demonstrates that in the face of a B. pseudomallei acute infection, poor glycaemic control impaired innate responses during the early stages of B. pseudomallei infection, contributing to the increased susceptibility of STZ-induced diabetics to this fatal disease.

Matched MeSH terms: Spleen/microbiology
Induced expression of the antimicrobial peptide melittin inhibits experimental infection by Mycoplasma gallisepticum in chickens

Lazarev VN, Stipkovits L, Biro J, Miklodi D, Shkarupeta MM, Titova GA, et al.

Microbes Infect., 2004 May;6(6):536-41.
PMID: 15158186

The in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with Mycoplasma gallisepticum was studied. The plasmid vector pBI/mel2/rtTA includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtTA. Aerosol administration of the vector, followed by infecting the chickens with M. gallisepticum 1226, is shown to inhibit development of infection. The inhibitory action was confirmed by a complex of clinical, pathomorphological, histological and serological studies, and also by comparing the M. gallisepticum reisolation frequency from the respiratory tract and internal organs. The data suggest that plasmid vectors expressing genes of antimicrobial peptides can be considered as potential agents for the prevention and treatment of mycoplasma infections in poultry farming.

Matched MeSH terms: Spleen/microbiology
The silvered leaf-monkey of Malaysia, Presbytis cristatus: disease model for human scrub typhus

Walker JS, Cadigan FC, Vosdingh RA, Chye CT

J Infect Dis, 1973 Aug;128(2):223-6.
PMID: 4198721
Matched MeSH terms: Spleen/microbiology
Fulltext Efficacy of a bacteriophage isolated from chickens as a therapeutic agent for colibacillosis in broiler chickens

Lau GL, Sieo CC, Tan WS, Hair-Bejo M, Jalila A, Ho YW

Poult Sci, 2010 Dec;89(12):2589-96.
PMID: 21076096 DOI: 10.3382/ps.2010-00904

The efficacy of bacteriophage EC1, a lytic bacteriophage, against Escherichia coli O78:K80, which causes colibacillosis in poultry, was determined in the present study. A total of 480 one-day-old birds were randomly assigned to 4 treatments groups, each with 4 pens of 30 birds. Birds from the control groups (groups I and II) received PBS (pH 7.4) or 10(10) pfu of bacteriophage EC1, respectively. Group III consisted of birds challenged with 10(8) cfu of E. coli O78:K80 and treated with 10(10) pfu of bacteriophage EC1 at 2 h postinfection, whereas birds from group IV were challenged with 10(8) cfu of E. coli O78:K80 only. All the materials were introduced into the birds by intratracheal inoculation. Based on the results of the present study, the infection was found to be less severe in the treated E. coli-challenged group. Mean total viable cell counts of E. coli identified on eosin methylene blue agar (designated EMB + E. coli) in the lungs were significantly lower in treated, E. coli-challenged birds than in untreated, E. coli-challenged birds on d 1 and 2 postinfection. The EMB + E. coli isolation frequency was also lower in treated birds; no E. coli was detectable in blood samples on any sampling day, and E. coli were isolated only in the liver, heart, and spleen of treated chickens at a ratio of 2/6, 1/6, and 3/6, respectively, at d 1 postinfection. The BW of birds from the E. coli-challenged group treated with bacteriophage EC1 were not significantly different from those of birds from both control groups but were 15.4% higher than those of the untreated, E. coli-challenged group on d 21 postinfection. The total mortality rate of birds during the 3-wk experimental period decreased from 83.3% in the untreated, E. coli-challenged birds (group IV) to 13.3% in birds treated with bacteriophage EC1 (group III). These results suggest that bacteriophage EC1 is effective in vivo and could be used to treat colibacillosis in chickens.

Matched MeSH terms: Spleen/microbiology
Burkholderia pseudomallei animal and human isolates from Malaysia exhibit different phenotypic characteristics

Lee SH, Chong CE, Lim BS, Chai SJ, Sam KK, Mohamed R, et al.

Diagn Microbiol Infect Dis, 2007 Jul;58(3):263-70.
PMID: 17350202

Burkholderia pseudomallei is a Gram-negative saprophytic soil bacterium, which is the etiologic agent of melioidosis, a severe and fatal infectious disease occurring in human and animals. Distinct clinical and animal isolates have been shown to exhibit differences in phenotypic trait such as growth rate, colony morphology, antimicrobial resistance, and virulence. This study was carried out to gain insight into the intrinsic differences between 4 clinical and 6 animal B. pseudomallei isolates from Malaysia. The 16S rRNA-encoding genes from these 10 isolates of B. pseudomallei were sequenced to confirm the identity of these isolates along with the avirulent Burkholderia thailandensis. The nucleotide sequences indicated that the 16S rRNA-encoding genes among the 10 B. pseudomallei isolates were identical to each other. However, the nucleotide sequence differences in the 16S rRNA-encoding genes appeared to be B. pseudomallei and B. thailandensis specific. The growth rate of all B. pseudomallei isolates was determined by generating growth curves at 37 degrees C for 72 h. The isolates were found to differ in growth rates with doubling time varying from 1.5 to 2.3 h. In addition, the B. pseudomallei isolates exhibited considerable variation in colony morphology when grown on Ashdown media, brain-heart infusion agar, and Luria-Bertani agar over 9 days of observation. Antimicrobial susceptibility tests indicated that 80% of the isolates examined were Amp(R) Cb(R) Kn(R) Gm(R) Chl(S) Te(S). Virulence of the B. pseudomallei clinical and animal isolates was evaluated in B. pseudomallei-susceptible BALB/c mice. Most of the clinical isolates were highly virulent. However, virulence did not correlate with isolate origin since 2 of the animal isolates were also highly virulent.

Matched MeSH terms: Spleen/microbiology
The effects of polymorphisms in IL-2, IFN-γ, TGF-β2, IgL, TLR-4, MD-2, and iNOS genes on resistance to Salmonella enteritidis in indigenous chickens

Tohidi R, Idris IB, Panandam JM, Bejo MH

Avian Pathol, 2012 Dec;41(6):605-12.
PMID: 23237374 DOI: 10.1080/03079457.2012.739680

Salmonella Enteritidis is a major cause of food poisoning worldwide, and poultry products are the main source of S. Enteritidis contamination for humans. Among the numerous strategies for disease control, improving genetic resistance to S. Enteritidis has been the most effective approach. We investigated the association between S. Enteritidis burden in the caecum, spleen, and liver of young indigenous chickens and seven candidate genes, selected on the basis of their critical roles in immunological functions. The genes included those encoding interleukin 2 (IL-2), interferon-γ (IFN-γ), transforming growth factor β2 (TGF-β2), immunoglobulin light chain (IgL), toll-like receptor 4 (TLR-4), myeloid differentiation protein 2 (MD-2), and inducible nitric oxide synthase (iNOS). Two Malaysian indigenous chicken breeds were used as sustainable genetic sources of alleles that are resistant to salmonellosis. The polymerase chain reaction restriction fragment-length polymorphism technique was used to genotype the candidate genes. Three different genotypes were observed in all of the candidate genes, except for MD-2. All of the candidate genes showed the Hardy-Weinberg equilibrium for the two populations. The IL-2-MnlI polymorphism was associated with S. Enteritidis burden in the caecum and spleen. The TGF-β2-RsaI, TLR-4-Sau 96I, and iNOS-AluI polymorphisms were associated with the caecum S. Enteritidis load. The other candidate genes were not associated with S. Enteritidis load in any organ. The results indicate that the IL-2, TGF-β2, TLR-4, and iNOS genes are potential candidates for use in selection programmes for increasing genetic resistance against S. Enteritidis in Malaysian indigenous chickens.

Matched MeSH terms: Spleen/microbiology
Fulltext Glycogen synthase kinase-3β inhibition improved survivability of mice infected with Burkholderia pseudomallei

Tay TF, Maheran M, Too SL, Hasidah MS, Ismail G, Embi N

Trop Biomed, 2012 Dec;29(4):551-67.
PMID: 23202600

The disease melioidosis, caused by the soil bacteria Burkholderia pseudomallei, often manifests as acute septicemia with high fatality. Glycogen synthase kinase-3β (GSK3β) plays a key role during the inflammatory response induced by bacteria. We used a murine model of acute melioidosis to investigate the effects of LiCl, a GSK3 inhibitor on experimental animal survivability as well as TNF-α, IL-1β, IFN-γ, IL-10 and IL-1Ra cytokine levels in blood, lung, liver and spleen of B. pseudomallei-infected mice. Our results showed that administration of 100 μg/g LiCl improved survivability of mice infected with 5 X LD50 of B. pseudomallei. Bacterial counts in spleen, liver and lungs of infected mice administered with LiCl were lower than non-treated controls. Our data also revealed that GSK3β is phosphorylated in the spleen, liver and lung of animals infected with B. pseudomallei. However in infected animals administered with LiCl, higher levels of pGSK3 were detected in the organs. Levels of proinflammatory cytokines (TNF-α, IL-1β and IFN-γ) and anti-inflammatory cytokines (IL-10 and IL-1Ra) in sera and organs tested were elevated significantly following B. pseudomallei infection. With GSK3β inhibition, pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β) were significantly decreased in all the samples tested whilst the levels of anti-inflammatory cytokines, IL-10 (spleen and lung) and IL-1Ra (spleen, liver and sera) were further elevated. This study represents the first report implicating GSK3β in the modulation of cytokine production during B. pseudomallei infection thus reiterating the important role of GSK3β in the inflammatory response caused by bacterial pathogens.

Matched MeSH terms: Spleen/microbiology

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