Previous Article | Next Article 
Infection and Immunity, March 2002, p. 1645-1647, Vol. 70, No. 3
0019-9567/02/$04.00+0 DOI: 10.1128/IAI.70.3.1645-1647.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.
Selective T-Cell Recognition of the N-Terminal Peptide of GroES in Tuberculosis
Boosbun Chua-Intra,1,
Robert J. Wilkinson,2 and Juraj Ivanyi1*
MRC Clinical Sciences Centre, Hammersmith Hospital, London W12 0NN,1
Wellcome Centre for Clinical Tropical Medicine, Imperial College School of Medicine, Northwick Park Hospital, Harrow HA1 3UJ, United Kingdom2
Received 16 July 2001/
Returned for modification 14 September 2001/
Accepted 19 December 2001

ABSTRACT
Peptides derived from the whole sequence of mycobacterial GroES
heat shock proteins were tested for the ability to induce the
proliferation of blood mononuclear cells from tuberculosis patients
and sensitized healthy subjects. The response to the N-terminal
peptide (residues 1 to 16) was found to be more frequent and
stronger in tuberculosis patients. This finding is exceptional,
considering that recognition of all other GroES peptides by
patients was either diminished or not different from that of
controls.

TEXT
Active tuberculosis (TB) is commonly associated with depressed
delayed-type skin hypersensitivity and in vitro proliferation
of blood lymphocytes (
5). T-cell anergy in leprosy is closely
linked to the pathology and clinical manifestations of the disease,
but the implications for TB are less clear. One mechanism involved
is the sequestration of CD4 T cells from the blood circulation
to the site of the disease, e.g., pleural fluid (
3,
12,
13),
associated with a pronounced change from Th1 to Th0 cytokine
secretion (
4). There are no obvious grounds for expecting the
depression in the blood T-cell response in TB to be antigen
or epitope specific. Nevertheless, the proliferation of T cells
in TB patients compared with that in sensitized healthy subjects
showed at least certain peptide-specific differences (
11). These
could have been related to the extent of recovery of blood T-cell
responses following chemotherapy (
12), but the frequency of
gamma interferon-secreting lymphocytes specific for ESAT-6 was
shown actually to fall rather than rise during antituberculosis
chemotherapy (
9).
The GroES (cpn10) heat shock protein of Mycobacterium tuberculosis is strongly recognized by T cells from healthy tuberculin reactors and patients with pleural TB (1). GroES is conserved between species, and its homologues are present in both prokaryotic and eukaryotic cells. It has been used as an experimental vaccine both against bacterial, e.g., Helicobacter pylori (6), infection and against autoimmune diseases, e.g., adjuvant arthritis (10). As the repertoire of T-cell responses to GroES revealed a distinct peptide-related specificity in leprosy (2), it seemed of interest to investigate if patients with active TB have similar or different hierarchies of peptide recognition. We tested pairs of peptides of very similar GroES sequences from M. tuberculosis and M. leprae, the latter being relevant to potentially reflect environmental sensitization with organisms of the M. avium complex. Peptide 16-mers overlapping by eight residues covering the entire protein sequence were produced on the Milligen 9050 Peptide Synthesiser using 9-fluorenylmethoxy carbonyl technology and purified on Sephadex G-15. Sequence integrity was verified by mass spectrometry, and homogeneity was verified by reverse-phase high-performance liquid chromatography (2).
The patients (TBP) and healthy donors (HS) were diagnosed in the United Kingdom. Ethnic origins were not matched between the groups: Caucasian (4 TBP, 12 HS), Indian (12 TBP, 4 HS), or African (9 TBP, 1 HS). The diagnosis of TB was confirmed in 20 of 25 patients by culture or histology and in the remaining 5 by clinical criteria. Of the 20 patients with pulmonary TB, 3 had pleural effusions and of the 5 with extrapulmonary cases, 3 had lymphatic disease and 2 had peritoneal disease. There was no evidence of human immunodeficiency virus infection in any of the patients tested. Blood was drawn before the onset of chemotherapy from all except one patient. All 17 healthy donors (14 males and three females with an average age of 36 years) were BCG vaccinated and had no history of TB. Both TBP and HS reacted to 1 tuberculin unit with a skin induration of greater than 5 mm, and blood samples were obtained with informed consent.
Peripheral blood mononuclear cells (PBMC) and peptide (50 µg/ml) in quadruplicate wells were incubated for 7 days. [3H]thymidine incorporation in cultures with antigen, if greater than 2.5-fold that achieved with medium alone (stimulation index,
2.5) was considered positive. PBMC from all TBP and HS responded positively to at least one peptide and also to purified protein derivative (results not shown). The total number of peptides recognized showed a significant difference (Fisher exact test) between the groups tested. Considering mean values for M. tuberculosis- and M. leprae-derived peptides, subjects in the HS group recognized a larger number of peptides (71% recognized more than five, and 29% recognized five or fewer) whereas those in the TBP group recognized fewer peptides (28% recognized more than five, and 72% recognized five or fewer). Similar results have been reported with respect to acr/16-kDa peptides in TB (8) and GroES peptides in leprosy (2).
The frequencies of response to the M. tuberculosis (T)- and M. leprae (L)-derived peptides by PBMC from subjects in the HS and TBP groups are presented in Fig. 1. The responsiveness to both the 1-16T and 1-16L peptides was higher in the TBP group than in the HS group. In contrast, responses to the all of the other peptides tested were either similar between the HS and TBP groups (p9-24, p17-32, and p25-40) or diminished in the TBP group (all in the carboxy-terminal section from p41-56). Responsiveness to the T and L series of peptides was similar in most instances, with a few exceptions. The observed lower responsiveness to p33-48T, 49-64L, and p65-80T is difficult to explain, and the possibility that these peptide preparations were of poorer quality cannot be excluded.
As our interest in disease association was greater than our
interest in fine specificity, we decided to evaluate the patterns
of antipeptide responses with respect to the more stimulatory
one from each T-L peptide pair. Stimulation indices of >2.5
to 6 were classified as moderately positive, and those of >6.0
were classified as strongly positive. We classified the stimulation
with individual peptides into five categories (A to E) on the
basis of TBP responsiveness in relation to HS responsiveness
(Fig.
2). Category A represents a pronounced increase in the
frequency and intensity of stimulation in the TBP group, which
was observed only with respect to the N-terminal peptide p1-16.
In contrast, no significant difference between the TBP and HS
groups was found with either the strongly stimulatory peptide
p9-24 (category B) or the weakly stimulatory peptides p17-32
and p25-40 (category C). By contrast, we observed a diminished
response of PBMC from TBP to four peptides classified in category
D and a marked decrease in responsiveness to the three peptides
of category E (p33-48, p57-72, and p81-100). Combining categories
D and E thus accounts for the overall narrowing of the peptide
repertoire in TBP.
The isolated case of an enhanced proliferative T-cell response
of TBP to the amino-terminal peptide p1-16 is thus unusual and
needs confirmation in a larger cohort of patients and controls.
Notably, the responsiveness to p1-16 was most prominent in the
9 African patients tested, but the mean value was not statistically
significantly different from that of the 12 Indian patients
tested. We also searched for a possible association with HLA-DR
alleles (comprehensively tested as described in reference
2),
but considering the small size of the groups and that the patient
and control populations were not ethnically matched, we could
not draw any meaningful conclusions (results not shown). The
enhanced response in active TB to only one peptide (p1-16) represents
a special situation, considering that out of the 11 peptides
of GroES tested, responses to 7 were diminished and responses
to 3 were similar in patients and controls. The reasons for
and mechanisms of this striking peptide specificity have not
been investigated but could be related to the structural motif
in residues 6 to 15, which have a pivotal role in the aggregation
of GroES into tetramers or heptamers (
7). It is a matter of
speculation whether this structural feature plays a role in
our empirical observation or whether the association is merely
coincidental. The mechanisms may involve an abrogation of the
sequestration of CD4 T cells from the blood to the site of disease.
Therefore, comparison of T-cell responses between blood and
pleural fluid, including their different cytokine profiles (
4),
would be of interest for further study. Considering the highly
conserved structure and common occurrence of GroES, our finding
could also be relevant to the immunogenicity and, by inference,
to the vaccinal capacity of GroES in other infectious and autoimmune
diseases.

ACKNOWLEDGMENTS
We thank Adrian Hills for the synthesis of peptides and the
clinical staff of Northwick Park Hospital for assistance in
diagnosing TB.

FOOTNOTES
* Corresponding author. Mailing address: Department of Oral Medicine & Pathology, 28th Floor Guy's Tower, Guy's Campus of King's College, London SE1 9RT, United Kingdom. Phone: 4420-7950 4568. Fax: 4420-7955 4455. E-mail:
juraj.ivanyi{at}kcl.ac.uk.

Present address: Leprosy Division, Department of Communicable Disease Control, Ministry of Public Health, Bangkok, Thailand. 

REFERENCES
1
- Barnes, P. F., V. Mehra, B. Rivoire, S. J. Fong, P. J. Brennan, M. S. Voegtline, P. Minden, R. A. Houghten, B. R. Bloom, and R. L. Modlin. 1992. Immunoreactivity of a 10-kDa antigen of Mycobacterium tuberculosis. J. Immunol. 148:1835-1840.
2
- Chua-Intra, B., S. Peerapakorn, N. Davey, S. Jurcevic, M. Busson, H. M. Vordermeier, C. Pirayavaraporn, and J. Ivanyi. 1998. T-cell recognition of mycobacterial GroES peptides in Thai leprosy patients and contacts. Infect. Immun. 66:4903-4909.[Abstract/Free Full Text]
3
- Dieli, F., G. Friscia, C. Di Sano, J. Ivanyi, M. Singh, R. Spallek, G. Sireci, L. Titone, and A. Salerno. 1999. Sequestration of T lymphocytes to body fluids in tuberculosis: reversal of anergy following chemotherapy. J. Infect. Dis. 180:225-228.[CrossRef][Medline]
4
- Dieli, F., M. Singh, R. Spallek, A. Romano, L. Titone, G. Sireci, G. Friscia, C. Di Sano, D. Santini, A. Salerno, and J. Ivanyi. 2000. Change of Th0 to Th1 cell-cytokine profile following tuberculosis chemotherapy. Scand. J. Immunol. 52:96-102.[CrossRef][Medline]
5
- Ellner, J. J. 1978. Pleural fluid and peripheral blood lymphocyte function in tuberculosis. Ann. Intern. Med. 89:932-933.
6
- Ferrero, R. L., J. M. Thiberge, I. Kansau, N. Wuscher, M. Huerre, and A. Labigne. 1995. The GroES homolog of Helicobacter pylori confers protective immunity against mucosal infection in mice. Proc. Natl. Acad. Sci. USA 92:6499-6503.[Abstract/Free Full Text]
7
- Fossati, G., P. Lucietto, P. Giuliani, A. R. Coates, S. Harding, H. Colfen, G. Legname, E. Chan, A. Zaliani, and P. Mascagni. 1995. Mycobacterium tuberculosis chaperonin 10 forms stable tetrameric and heptameric structures. Implications for its diverse biological activities. J. Biol. Chem. 270:26159-26167.[Abstract/Free Full Text]
8
- Friscia, G., H. M. Vordermeier, G. Pasvol, D. P. Harris, C. Moreno, and J. Ivanyi. 1995. Human T cell responses to peptide epitopes of the 16-kD antigen in tuberculosis. Clin. Exp Immunol. 102:53-57.[Medline]
9
- Lalvani, A., P. Nagvenkar, Z. Udwadia, A. A. Pathan, K. A. Wilkinson, J. S. Shastri, K. Ewer, A. V. Hill, A. Mehta, and C. Rodrigues. 2001. Enumeration of T cells specific for RD1-encoded antigens suggests a high prevalence of latent Mycobacterium tuberculosis infection in healthy urban Indians. J. Infect. Dis. 183:469-477.[CrossRef][Medline]
10
- Ragno, S., V. R. Winrow, P. Mascagni, P. Lucietto, F. Di Pierro, C. J. Morris, and D. R. Blake. 1996. A synthetic 10-kD heat shock protein (hsp10) from Mycobacterium tuberculosis modulates adjuvant arthritis. Clin. Exp. Immunol. 103:384-390.[CrossRef][Medline]
11
- Vordermeier, H. M., D. P. Harris, G. Friscia, E. Roman, H. M. Surcel, C. Moreno, G. Pasvol, and J. Ivanyi. 1992. T cell repertoire in tuberculosis: selective anergy to an immunodominant epitope of the 38-kDa antigen in patients with active disease. Eur. J. Immunol. 22:2631-2637.[Medline]
12
- Wilkinson, R. J., H. M. Vordermeier, K. A. Wilkinson, A. Sjolund, C. Moreno, G. Pasvol, and J. Ivanyi. 1998. Peptide-specific T cell response to Mycobacterium tuberculosis: clinical spectrum, compartmentalization, and effect of chemotherapy. J. Infect. Dis. 178:760-768.[Medline]
13
- Zhang, M., M. K. Gately, E. Wang, J. Gong, S. F. Wolf, S. Lu, R. L. Modlin, and P. F. Barnes. 1994. Interleukin 12 at the site of disease in tuberculosis. J. Clin. Investig. 93:1733-1739.
Infection and Immunity, March 2002, p. 1645-1647, Vol. 70, No. 3
0019-9567/02/$04.00+0 DOI: 10.1128/IAI.70.3.1645-1647.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Sung, N., Takayama, K., Collins, M. T.
(2004). Possible Association of GroES and Antigen 85 Proteins with Heat Resistance of Mycobacterium paratuberculosis. Appl. Environ. Microbiol.
70: 1688-1697
[Abstract]
[Full Text]