Induction of CD8 T Cells against a Novel Epitope in TB10.4: Correlation with Mycobacterial Virulence and the Presence of a Functional Region of Difference-1

Billeskov, Rolf; Vingsbo‐Lundberg, Carina; Andersen, Peter; Dietrich, Jes

doi:10.4049/jimmunol.179.6.3973

Cited by 92 publications

(97 citation statements)

References 46 publications

(175 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…administration of BCG at high doses ($1 Â 10 6 CFU/mouse), which does give a significant CD8 response specific for TB10.4) (Fig. 2) [15,24,25]. The recombinant BCG::RD1-strain expressing the ESAT-6 secretion system showed similar TB10.4 epitope recognition patterns as virulent M.tb, both recognizing the MHC-I restricted epitopes in P1 and P2 and the MHC-II restricted epitope in P8 (data not shown), corresponding to earlier described epitopes [24,26,27].…”

Section: Discussionmentioning

confidence: 99%

“…2) [15,24,25]. The recombinant BCG::RD1-strain expressing the ESAT-6 secretion system showed similar TB10.4 epitope recognition patterns as virulent M.tb, both recognizing the MHC-I restricted epitopes in P1 and P2 and the MHC-II restricted epitope in P8 (data not shown), corresponding to earlier described epitopes [24,26,27]. As it has been suggested that the RD1 region enables M.tb to escape the phagosome [28], it could be speculated that altered intracellular trafficking of BCG might lead to a different epitope pattern and/ or to new protective epitopes.…”

Section: Discussionmentioning

confidence: 99%

“…Experiments were conducted in accordance with the regulations set forward by the Danish Ministry of Justice and animal protection committees by Danish Animal Experiments Inspectorate Permit 2004-561-868 (of January 7, 2004, and in compliance with European Community Directive 86/609. Antigens rTB10.4 was produced in E. coli as described earlier [24]. Native TB10.4 and the native complex of TB10.4/TB9.8 (Rv0288/ Rv0287) was homologously overexpressed in M. smegmatis using the pMyNT vector (Arie Geerlof, EMBL-HH) and purified using a NiNTA column.…”

Section: Animal Handlingmentioning

confidence: 99%

“…Intracellular cytokine staining of T cells was done as described previously [24]. Briefly, cells were stimulated for 1 h with 2 mg/ mL Ag and subsequently incubated for 5 h with 10 mg/mL brefeldin A (Sigma-Aldrich) at 371C and then stained for surface markers, permeabilized and subsequently stained for intracellular cytokine expression.…”

Section: Flow Cytometric Analysismentioning

confidence: 99%

See 3 more Smart Citations

Difference in TB10.4 T‐cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis

et al. 2010

Self Cite

View full text Add to dashboard Cite

Most novel vaccines against infectious diseases are based on recombinant Ag; however, only few studies have compared Ag-specific immune responses induced by natural infection with that induced by the same Ag in a recombinant form. Here, we studied the epitope recognition pattern of the tuberculosis vaccine Ag, TB10.4, in a recombinant form, or when expressed by the pathogen Mycobacterium tuberculosis (M.tb), or by the current anti-tuberculosis vaccine, Mycobacterium bovis BCG. We showed that BCG and M.tb induced a similar CD4 1 T-cell specific TB10.4 epitope-pattern, which differed completely from that induced by recombinant TB10.4. This difference was not due to post-translational modifications of TB10.4 or because TB10.4 is secreted from BCG and M.tb as a complex with Rv0287. In addition, BCG and TB10.4/CAF01 were both taken up by DC and macrophages in vivo, and in vitro uptake experiments revealed that both TB10.4 and BCG were transported to Lamp 1 -compartments. BCG and TB10.4 however, were directed to different types of Lamp 1 -compartments in the same APC, which may lead to different epitope recognition patterns. In conclusion, we show that different vectors can induce completely different recognition of the same protein.Key words: Epitopes . Intracellular localization . Subdominant . T cells . Vaccine uptake IntroductionThe size, shape and nature of a synthetic recombinant vaccine and its target pathogen differ significantly. For instance, bacteria are typically in the range of 0.5-10 mm in diameter, which exceed the size of most viruses by 10 to 100-fold, and protein based adjuvanted vaccines are even smaller. In addition, compared with vaccines based on recombinant proteins and an adjuvant, pathogens are often taken up by different mechanisms by the cells of the immune system [1]. The different uptake mechanisms could lead to different intracellular processing of Ag, giving rise to different epitopes [1]. Furthermore, live pathogens express a wide range of specific lipids 1342and proteins that bind a variety of pattern-recognition receptors on phagocytes and induce signaling through these receptors, whereas recent evidence suggests subunit vaccines more specifically tend to target DC through activation of toll-like receptors [2]. These differences are likely to lead to different responses with regard to the priming of the early immune response [3]. For instance, the main host cell of the intracellular pathogen Mycobacterium tuberculosis (M.tb), the causative agent of tuberculosis in humans, is thought to be macrophages [4]; however, although mycobacteria are mainly taken up by macrophages, mycobacteria can infect a wide range of cells including neutrophils, epithelial cells and other cell types [5,6]. On the other hand, viral vaccine vectors have been shown to be ingested largely by immature DC [1], and soluble Ag formulated in cationic adjuvants such as CAF01 or IC31 are also believed to target DC [7,8]. Different types of APC have different mechanisms of Ag uptake, different pH levels in lysosomal co...

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Animal Handlingmentioning

confidence: 99%

Section: Flow Cytometric Analysismentioning

confidence: 99%

See 2 more Smart Citations

Difference in TB10.4 T‐cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the last years, flow cytometry evaluation of cytokine secretion profiles and cell surface phenotypes of peripheral blood T cells have been employed in the attempt to differentiate active and latent TB infection [ 5,11,12 ]. A large body of evidence suggests the important contribution of CD8 T cells in the MTB-specific immune response [6][7][8]13 ]. The latter display specific effector functions performed upon recognition of mycobacterial antigens -production of IFN-γ, lysis of infected host cells, and direct killing of MT bacteria [ 14 ].…”

mentioning

confidence: 99%

Peripheral Blood CD8 T Cell Response in Different Phases of MTB Infection

Nikolova¹,

Muhtarova²,

Drenska³

et al. 2013

Proceeding BAS

View full text Add to dashboard Cite

A reliable approach differentiating between active and latent TB infection (LTBI) is yet unavailable. Recent data suggest the involvement of CD8 T cells in protective response to mycobacterium tuberculosis (MTB). We compared the antigen-specific responses and subset composition of peripheral blood CD8 T cells in patients with active infection (ATB), recent household contacts (RC), highly-exposed health-care workers (HW), and BCG-vaccinated healthy controls (HC). Study groups included 20 ATB, 21 RH, 21 HW and 15 HC. Active TB was diagnosed according to microbiological and clinical criteria. RD1-specific CD4 and CD8 T cells were determined by intracellular cytokine staining (ICS). CD8 T subsets were defined as naïve (CD45RA+CD27+), memory (M, CD45RA-CD27+), effector (E, CD27-CD45RA-), and terminal effector (TE, CD27-CD45RA+), and analyzed by flow cytometry. The levels of RD-1-specific CD4 T cells were highest in ATB but not significantly different from LTBI groups. A significant RD-1-specific CD8 T cell IFNγ response (0.289%) differentiated RC from ATB, HE and HC subjects (0.053, 0.027 and 0.011, p < 0.05) and was associated with decreased M/TE ratio. Finally, an increased M/E CD8 T ratio distinguished HW from RC and ATB subjects (7.6 vs. 2.4 and 2.6, p < 0.05). The study of MTB-specific CD8 T-cell response in combination with CD8 T subset composition adds to the differentiation between active and latent TB.Key words: CD8 T-cell response, RD-1-specific T cells, ICS, MTB infection 587 Introduction. Mycobacterium tuberculosis (MTB) is one of the most frequent causes of infectious morbidity worldwide [ 1 ]. A large majority of M. tuberculosis-infected individuals remains asymptomatic while unable to clear the bacterium, with a lifelong probability to develop active TB of about 5-10% [ 2 ]. This probability is highest within the first two years after infection, and in subjects with recently-established LTBI preventive therapy can be effective. Thus the distinction between the different forms and stages of MTB infection is fundamental for the effective control of TB transmission.The correct diagnosis of LTBI remains a challenge. Until recently, tuberculin skin test (TST) has been the most frequently used screening method, leading to a high rate of false positive results in M. bovis BCG-vaccinated individuals, and false negative tests in immunosuppressed persons. The new interferon gamma release assays (IGRAs) employing RD-1 antigens specific for virulent mycobacteria have excellent specificity unaffected by BCG vaccination and increased sensitivity While CD4 Th1 cells are the well-known effectors of MTB-specific immune response, a lot of evidence from humans and from animal models indicate a critical role of CD8 T cells for MTB control as well [ 6-8 ]. However, data about the characteristics of CD8 T cell responses in individuals with LTBI and in patients with active tuberculosis are still scarce.In this study, using intracellular cytokine staining (ICS) and flow cytometry, we compared the CD8 T cell responses ...

show abstract

Mycobacterium chelonae sensitisation induces CD4⁺‐mediated cytotoxicity against BCG

Wei

Seah

2009

Eur J Immunol

View full text Add to dashboard Cite

Significant variability in efficacy of live Mycobacterium bovis BCG as a tuberculosis vaccine is observed globally. Effects of pre-vaccination sensitisation to non-tuberculous environmental mycobacteria (Env) are suspected to underlie this phenomenon, but the mechanisms remain unclear. We postulated that it could be due to Env-specific T cells exerting cytotoxicity against BCG-infected host cells. After murine sensitisation with heat-killed antigens of different Env species, splenocytes from M. chelonae (CHE)-sensitised mice exerted the strongest cytotoxicity against autologous BCG-infected macrophages. This cytotoxicity was correlated with reduced BCG viability. The cytotoxicity was reduced by the depletion of CD4 1 , but not CD8 1 or CD56 1 cells, and CD4 1 cells showed higher percentage of cytotoxicity than CD4 À cells, supporting a role for CD4 1 cells in CHEinduced, BCG-specific cytotoxicity. Additionally, this cytotoxicity was IFN-c, perforin and FasL dependent. After CHE-sensitisation and subsequent BCG intranasal infection, there was significant expansion of lung CD4 1 cells, the main cell type producing IFN-c. This was associated with 2-and 6-fold reductions in lung BCG counts 1 and 3 wk, respectively postinfection, relative to non-sensitised mice. This is the first report describing cytotoxicity against BCG-infected cells as a mechanism underlying the influence of Env sensitisation on subsequent BCG responses.Key words: Bacterial infections . CD4 T cells . Cytotoxicity . Host-pathogen interactions .Immune responses Supporting Information available online IntroductionThe protective efficacy of Mycobacterium bovis BCG against tuberculosis (TB) varies in clinical trials from 0 to 80% [1]. Several trials showing no protection were conducted in developing countries with high TB incidence; among these are many tropical regions where environmental mycobacteria (Env) are prevalent [2] and human immune exposure to Env is high [3]. Among hypotheses proposed for the variability in BCG efficacy [4,5], those invoking the influence of Env exposure on immune modulation of the BCG response are most widely studied and supported [3,[6][7][8]. Env are free-living members of the Mycobacterium genus, dwelling in the soil and open waters, and many species are genetically closely related to BCG (average495% similarity) [9,10]. Palmer first observed in guinea pigs [11] that Env exposure may confer some immune protection against TB, masking the effects of subsequent BCG vaccination. This was later also [6,13]. This may be due to cross-reactive memory responses to shared antigens, but the nature of Env-induced effector cells and how they interact subsequently with BCG-infected cells, were not described in those studies.There is evidence for human T cells with mycobacteriumspecific cytotoxic activity [14] and that mycobacteria can be killed via cytotoxicity mechanisms [15,16]. Cytotoxicity against mycobacterium-infected cells may be influenced by . Therefore, we hypothesised that the curtailment of BCG survival after Env exposu...

show abstract

Induction of CD8 T Cells against a Novel Epitope in TB10.4: Correlation with Mycobacterial Virulence and the Presence of a Functional Region of Difference-1

Cited by 92 publications

References 46 publications

Difference in TB10.4 T‐cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis

Difference in TB10.4 T‐cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis

Peripheral Blood CD8 T Cell Response in Different Phases of MTB Infection

Mycobacterium chelonae sensitisation induces CD4⁺‐mediated cytotoxicity against BCG

Contact Info

Product

Resources

About

Induction of CD8 T Cells against a Novel Epitope in TB10.4: Correlation with Mycobacterial Virulence and the Presence of a Functional Region of Difference-1

Cited by 92 publications

References 46 publications

Difference in TB10.4 T‐cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis

Difference in TB10.4 T‐cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis

Peripheral Blood CD8 T Cell Response in Different Phases of MTB Infection

Mycobacterium chelonae sensitisation induces CD4+‐mediated cytotoxicity against BCG

Contact Info

Product

Resources

About

Mycobacterium chelonae sensitisation induces CD4⁺‐mediated cytotoxicity against BCG