HLA-DQ molecules and the control ofMycobacterium leprae-specific T cell nonresponsiveness in lepromatous leprosy patients

1990 ◽  
Vol 20 (10) ◽  
pp. 2347-2350 ◽  
Author(s):  
Tom H. M. Ottenhoff ◽  
Charlotte Walford ◽  
Yasuharu Nishimura ◽  
N. B. B. Reddy ◽  
Takehiko Sasazuki
2011 ◽  
Vol 80 (2) ◽  
pp. 742-752 ◽  
Author(s):  
Mehervani Chaduvula ◽  
A. Murtaza ◽  
Namita Misra ◽  
N. P. Shankar Narayan ◽  
V. Ramesh ◽  
...  

ABSTRACTLsr2 protein ofMycobacterium lepraewas shown earlier to elicit B and T cell responses in leprosy patients (20, 28). Lymphoproliferation toM. lepraeand Lsr2 antigens was observed in >70% of tuberculoid (T) patients and in 16 and 34% of lepromatous (L) patients, respectively. We focused on theM. lepraenonresponders in the lepromatous group using 22 synthetic Lsr2 peptides (end-to-end peptides A to F and overlapping peptides p1 to p16) inin vitroT cell responses. A total of 125 leprosy and 13 tuberculosis patients and 19 healthy controls from the area of endemicity (here, healthy controls, or HC) were investigated. The highest responses were observed (67 to 100%) in HC for all peptides except p1 to p3, and the lowest was observed in tuberculosis patients. Significant differences in lymphoproliferation were observed in T, L, and HC groups (analysis of variance [ANOVA],P= 0.000 to 0.015) for all end-to-end peptides except B and for p5 and p7 to p10. Hierarchical recognition between lepromatous and tuberculoid leprosy was noted for p8 (P< 0.05) and between the HC and L groups for p7 to p10, p15, and p16 (P< 0.005 toP< 0.02). Significant lymphoproliferation was observed to peptides A to F and p1 to p9, p11, p12, p15, p16 (P= 0.000 to 0.001) with 40% responding to peptides C and p16 in L patients. Lepromatous patients also showed significantly higher levels of a gamma interferon (IFN-γ) response to peptide C than to other peptides (P< 0.05). Major histocompatibility complex (MHC) class II bias for peptide recognition was not observed. These studies indicate that Lsr2 has multiple T cell epitopes that inducein vitroT cell responses in the highly infective lepromatous leprosy patients.


PLoS ONE ◽  
2016 ◽  
Vol 11 (10) ◽  
pp. e0164543 ◽  
Author(s):  
Luciana Nahar dos Santos ◽  
Pedro Henrique Lopes da Silva ◽  
Iris Maria Peixoto Alvim ◽  
José Augusto da Costa Nery ◽  
Flávio Alves Lara ◽  
...  

1990 ◽  
Vol 61 (1) ◽  
Author(s):  
H. K. GILL ◽  
D. S. RIDLEY ◽  
J. GANESAN ◽  
A. S. MUSTAFA ◽  
R. J. W. REES ◽  
...  

1998 ◽  
Vol 66 (10) ◽  
pp. 4903-4909 ◽  
Author(s):  
Boosbun Chua-Intra ◽  
Somchai Peerapakorn ◽  
Nick Davey ◽  
Stipo Jurcevic ◽  
Marc Busson ◽  
...  

ABSTRACT We report here the mapping of T-cell-stimulatory determinants of the GroES 10-kDa heat shock protein homologues from Mycobacterium leprae and Mycobacterium tuberculosis, which are known as major immunogens in mycobacterial infections. Peripheral blood mononuclear cells (PBMC) from treated tuberculoid leprosy or lepromatous leprosy patients and from healthy household or hospital staff contacts of the patients were cultured with 20 16-mer peptides covering the entire sequences of both M. leprae andM. tuberculosis GroES. The total number of recognized peptides was found to be the largest in family contacts, while responder frequencies to the individual tested peptides varied (5 to 80%) with specificity between the patient and contact groups. Proliferative responses to some peptides showed positive or negative associations of low statistical significance with DR and DQ alleles, though responses to most GroES peptides were genetically permissive. Notably, the sequence of the 25–40 peptide of M. leprae, but not that of M. tuberculosis, was more frequently stimulatory in tuberculoid leprosy patients than in either group of sensitized healthy contacts. This peptide bound to a number of HLA-DR molecules, of which HLA-DRB5*0101 had the strongest affinity. The epitope core binding to this allele was localized to the 29-to-37 sequence, and its key residue was localized to the M. leprae-specific glutamic acid at position 32. This epitope may be of interest for the development of a blood test- or skin test-based diagnostic reagent for tuberculoid leprosy, subject to further clinical evaluation in untreated patients.


1985 ◽  
Vol 162 (3) ◽  
pp. 917-929 ◽  
Author(s):  
G Kaplan ◽  
D E Weinstein ◽  
R M Steinman ◽  
W R Levis ◽  
U Elvers ◽  
...  

In lepromatous leprosy, there is extensive replication of Mycobacterium leprae (M. leprae) within dermal macrophages. This lack of microbial resistance has been attributed to a defective cell-mediated immune response to M. leprae antigens. We have examined the in vitro response of T cells to M. leprae to determine if hyporesponsiveness could be reversed. The study included 40 unselected patients from New York and from Colombia, most with the severe lepromatous form of the disease. We first noted that lepromatous leprosy patients were of two types: those unable to respond, as assessed by T cell proliferation and immune (gamma) interferon (IFN-gamma) release, and a second group, exhibiting low but detectable responses relative to tuberculoid controls. When the effect of exogenous recombinant interleukin-2 (IL-2) on the response to M. leprae antigens was compared in the two groups, many of the low responders, but not the nonresponders, showed enhanced proliferation and IFN-gamma release. To evaluate a possible suppressive effect of monocytes, these cells were eliminated with a cell-specific monoclonal antibody and complement. Depletion of monocytes often expanded preexisting weak responses but did not reverse the anergy of the M. leprae nonresponders. The enhancement was not M. leprae-specific, since it was also observed when bacillus Calmette-Guerin was the antigenic stimulus for proliferation and IFN-gamma production. Removal of the suppressor T cell subset, with OKT8 antibody and complement, also did not restore responses in nonresponder patients. We conclude that a sizable number of lepromatous leprosy patients exhibit a low degree of responsiveness to M. leprae and that the responses can be enhanced in vitro with IL-2 or with monocyte depletion. Nonresponsiveness, however, cannot be reversed. Since currently available assays measure the function of previously sensitized T cells, suppressor mechanisms may yet contribute to defective cell-mediated immunity by impairing the initial sensitization to M. leprae antigens.


2021 ◽  
pp. 004947552199849
Author(s):  
Prakriti Shukla ◽  
Kiran Preet Malhotra ◽  
Parul Verma ◽  
Swastika Suvirya ◽  
Abir Saraswat ◽  
...  

Non-neuropathic ulcers in leprosy patients are infrequently seen, and atypical presentations are prone to misdiagnosis. We evaluated diagnosed cases of leprosy between January 2017 and January 2020 for the presence of cutaneous ulceration, Ridley–Jopling subtype of leprosy, reactions and histologic features of these ulcerations. Treatment was given as WHO recommended multi-bacillary multi-drug therapy. We found 17/386 leprosy patients with non-neuropathic ulcers. We describe three causes – spontaneous cutaneous ulceration in lepromatous leprosy (one nodular and one diffuse), lepra reactions (five patients with type 1; nine with type 2, further categorised into ulcerated Sweet syndrome-like who also had pseudoepitheliomatous hyperplasia, pustulo-necrotic and necrotic erythema nodosum leprosum) and Lucio phenomenon (one patient). Our series draws attention towards the different faces of non-neuropathic ulcers in leprosy, including some atypical and novel presentations.


1996 ◽  
Vol 183 (3) ◽  
pp. 1253-1258 ◽  
Author(s):  
W W Kwok ◽  
M E Domeier ◽  
M L Johnson ◽  
G T Nepom ◽  
D M Koelle

The association of specific HLA-DQ alleles with autoimmunity is correlated with discrete polymorphisms in the HLA-DQ sequence that are localized within sites suitable for peptide recognition. The polymorphism at residue 57 of the DQB1 polypeptide is of particular interest since it may play a major structural role in the formation of a salt bridge structure at one end of the peptide-binding cleft of the DQ molecules. This polymorphism at residue 57 is a recurrent feature of HLA-DQ evolution, occurring in multiple distinct allelic families, which implies a functional selection for maintaining variation at this position in the class II molecule. We directly tested the amino acid polymorphism at this site as a determinant for peptide binding and for antigen-specific T cell stimulation. We found that a single Ala--&gt;Asp amino acid 57 substitution in an HLA-DQ3.2 molecule regulated binding of an HSV-2 VP-16-derived peptide. A complementary single-residue substitution in the peptide abolished its binding to DQ3.2 and converted it to a peptide that can bind to DQ3.1 and DQ3.3 Asp-57-positive MHC molecules. These binding studies were paralleled by specific T cell recognition of the class II-peptide complex, in which the substituted peptide abolished T cell reactivity, which was directed to the DQ3.2-peptide complex, whereas the same T cell clone recognized the substituted peptide presented by DQ3.3, a class II restriction element differing from DQ3.2 only at residue 57. This structural and functional complementarity for residue 57 and a specific peptide residue identifies this interaction as a key controlling determinant of restricted recognition in HLA-DQ-specific immune response.


2008 ◽  
Vol 77 (2) ◽  
pp. 896-903 ◽  
Author(s):  
Rachel M. Stenger ◽  
Martien C. M. Poelen ◽  
Ed E. Moret ◽  
Betsy Kuipers ◽  
Sven C. M. Bruijns ◽  
...  

ABSTRACT P.69 pertactin (P.69 Prn), an adhesion molecule from the causative agent of pertussis, Bordetella pertussis, is present in cellular and most acellular vaccines that are currently used worldwide. Although both humoral immunity and cellular immunity directed against P.69 Prn have been implicated in protective immune mechanisms, the identities of CD4+ T-cell epitopes on the P.69 Prn protein remain unknown. Here, a single I-Ad-restricted B. pertussis conserved CD4+ T-cell epitope at the N terminus of P.69 Prn was identified by using a BALB/c T-cell hybridoma. The epitope appeared immunodominant among four other minor strain-conserved P.69 Prn epitopes recognized after vaccination and B. pertussis infection, and it was capable of evoking a Th1/Th17-type cytokine response. B. pertussis P.69 Prn immune splenocytes did not cross-react with natural variants of the epitope as present in Bordetella parapertussis and Bordetella bronchiseptica. Finally, it was found that the immunodominant P.69 Prn epitope is broadly recognized in the human population by CD4+ T cells in an HLA-DQ-restricted manner. During B. pertussis infection, the epitope was associated with a Th1-type CD4+ T-cell response. Hence, this novel P.69 Prn epitope is involved in CD4+ T-cell immunity after B. pertussis vaccination and infection in mice and, more importantly, in humans. Thus, it may provide a useful tool for the evaluation of the type, magnitude, and maintenance of B. pertussis-specific CD4+ T-cell mechanisms in preclinical and clinical vaccine studies.


Sign in / Sign up

Export Citation Format

Share Document