PDF eBook
Sample Preview
Size 131k
Free
Download a sample of the first 25 pages
Download Preview

Entire PDF eBook
1185k
$17
Get instant access to an entire eBook
Buy PDF Password Download Complete PDF
eBook editions

Molecular Mechanism of Chagas' Disease

Lymphocyte activation by the Trypanosoma cruzi trans-sialidase

by Wenda Gao
 Paperback   small ebook icon   eBook PDF
Publisher:  Dissertation
Pub date:  2002
Pages:  205
ISBN-10:  1581121423
ISBN-13:  9781581121421
Categories:  Health Sciences  Medicine  Health & Fitness

Abstract

Polyclonal lymphocyte activation and hypergammaglobulinemia characterize the acute phase of Chagas' disease, a debilitating condition caused by Trypanosoma cruzi. Such pathogenic hyper-reactivities not only compromise specific host defense against the pathogen, but may also contribute to infection-induced chronic autoimmune responses. Characterizing parasite-derived factors driving non-specific immune responses will provide insights for parasite evasion of host specific immunity. This study shows that T. cruzi trans-sialidase (TS) is one such polyclonal activator for normal murine lymphoid and non-lymphoid cells in at least three aspects. First, TS induces aggregation of immune cells and secretion of cytokines, such as IL-6. Second, TS is a T-independent B cell mitogen, directly stimulating polyclonal B cell proliferation independent of IL-6, CD40, CD43, Toll-like receptor-4 (TLR-4), and mIg crosslinking. While TS is mitogenic to wild-type B cells, mostly CD5- B2 cells, it fails to induce any proliferation of B cells from Bruton's tyrosine kinase (Btk)-defective X-linked immune deficient (xid) mice, suggesting that Btk is involved in TS signaling. Furthermore, in vivo administration of TS is followed by polyclonal Ig secretion that peaks 4-6 days after injection, before detectable TS-specific antibodies. Third, although TS does not directly stimulate T cells, it potentiates antigen specific and nonspecific T cell responses through the activation of APC, such as macrophages and B cells. TS potentiation is observed in splenocytes deficient of CD28, ICAM-1, CD40L or CD43. However, optimal TS-potentiation requires IL-6 and Btk, as it is significantly reduced in splenocytes from IL-6 -/- and xid mice.

The C-terminal tandem repeat domain (LTR), but not the N-terminal catalytic domain (CD) of TS, is the active moiety that mediates TS-induced cell aggregation, IL-6 secretion, B cell and macrophage activation. At non-mitogenic concentrations, however, LTR inhibits mouse T cell activation and blocks TS-potentiated T cell response. A working model for the actions of TS, its domains and TS receptor is proposed.

The results indicate that TS is a parasite-derived factor that directly and indirectly activates both APC and T cells, disturbing host lymphocyte homeostasis and cytokine regulation. Thus, TS may drive polyclonal lymphocyte activation in acute infection, potentially contributing to the immune evasion of the parasite, as well as the autoimmune abnormality in chronic Chagas' disease.




PDF eBook
Sample Preview
Size 131k
Free
Download a sample of the first 25 pages
Download Preview

Entire PDF eBook
1185k
$17
Get instant access to an entire eBook
Buy PDF Password Download Complete PDF
eBook editions
Share this book



Relevant events
OCT
20
SIOP 2025
International Society of Paediatric oncology SIOP 2025 Congress Secretariat WELCOME TO SIOP 2025! It is with great honor and privilege that we extend a heartfelt invitation to you to join us for the 57th Annual SIOP Congress. We are thrilled to once again come together, this time in the char...
International Society of Paediatric oncology SIOP 2025 Congress Secretariat WELCOME TO SIOP 2025! It is with great honor and privilege that we extend a heartfelt invitation to you to join us for the 57th Annual SIOP Cong...
International Society of Paediatric oncology SIOP 2025 Congress Secretariat WELCOME TO SIOP 2025! It is with great honor and privilege that we ext...
International Society of Paediatric oncology SIOP 2025 Congress Secretariat WELCOME TO SIOP 2025! It is with great honor ...
20 - 23 Oct 2025
Amsterdam, Netherlands
OCT
27
EUROREPRO24
Euro Reproduction, Fertility and Gynecology Conference Euro Reproduction, Fertility and Gynecology Conference 2025 will feature the most recent scientific advances from across the spectrum of reproductive biology, to include obstetrics, fertility, PCOS, pregnancy, gynecologic ...
Euro Reproduction, Fertility and Gynecology Conference Euro Reproduction, Fertility and Gynecology Conference 2025 will feature the most recent scientific advances from across the spectrum of reproducti...
Euro Reproduction, Fertility and Gynecology Conference Euro Reproduction, Fertility and Gynecology Conference 2025 will feature ...
Euro Reproduction, Fertility and Gynecology Conference Euro Reproduction, Fertility and Gynecology Conf...
27 - 28 Oct 2025
Rome, Italy
NOV
6
ICDB 2025
2nd International Conference on Dementia and Brain Disorders Scitechseries introducing with great excitement about "2nd International Conference on Dementia and Brain Disorders" (ICDB 2025) invites all the participants across the globe to attend from November 06-07, 2025, London, UK...
2nd International Conference on Dementia and Brain Disorders Scitechseries introducing with great excitement about "2nd International Conference on Dementia and Brain Disorders" (ICDB 2025) invites all the pa...
2nd International Conference on Dementia and Brain Disorders Scitechseries introducing with great excitement about "2nd International ...
2nd International Conference on Dementia and Brain Disorders Scitechseries introducing with great excitement ...
06 - 07 Nov 2025
Online Event | United Kingdom
JAN
14
ICONAN 2026
International Conference on Nanomedicine and Nanobiotechnology Celebrating its 10th year, ICONAN 2026 will reflect on the remarkable advancements in nanomedicine while looking toward its future potential. The conference will emphasize a deeper understanding of the nano-bio interaction...
International Conference on Nanomedicine and Nanobiotechnology Celebrating its 10th year, ICONAN 2026 will reflect on the remarkable advancements in nanomedicine while looking toward its future potential. The c...
International Conference on Nanomedicine and Nanobiotechnology Celebrating its 10th year, ICONAN 2026 will reflect on the remarkable adv...
International Conference on Nanomedicine and Nanobiotechnology Celebrating its 10th year, ICONAN 2026 will refl...
14 - 16 Jan 2026
Rome, Italy
MAR
19
DENTAL 2026
11th Edition of International Conference on Dental Innovations and Technologies We are excited to welcome you to Dental 2026 – 11th Edition of International Conference on Dental Innovations and Technologies, taking place from March 19-21, 2026, in Singapore, with virtual access available. Aligned with...
11th Edition of International Conference on Dental Innovations and Technologies We are excited to welcome you to Dental 2026 – 11th Edition of International Conference on Dental Innovations and Technologies, taking place from M...
11th Edition of International Conference on Dental Innovations and Technologies We are excited to welcome you to Dental 2026 – 11th Edition of Internatio...
11th Edition of International Conference on Dental Innovations and Technologies We are excited to welcome you to Dental 2026 – 1...
19 - 21 Mar 2026
, Singapore
MAR
23
IOC 2026
4th Edition of International Ophthalmology Conference Shaping the future of ophthalmology, the 4th Edition of International Ophthalmology Conference (IOC 2026) will take place from March 23-25, 2026, in Singapore and Virtually. With a focus on “Unlocking New Frontiers in Visi...
4th Edition of International Ophthalmology Conference Shaping the future of ophthalmology, the 4th Edition of International Ophthalmology Conference (IOC 2026) will take place from March 23-25, 2026, i...
4th Edition of International Ophthalmology Conference Shaping the future of ophthalmology, the 4th Edition of International Oph...
4th Edition of International Ophthalmology Conference Shaping the future of ophthalmology, the 4th Edi...
23 - 25 Mar 2026
, Singapore
MAY
7
ICPCH
2nd International Conference on Pediatrics and Child Health We are cordially welcome you to join the 2nd International Conference on Pediatrics and Child Health, scheduled for May 07–08, 2026, in Kuala Lumpur, Malaysia under the theme “From Prevention to Precision: Global Advances ...
2nd International Conference on Pediatrics and Child Health We are cordially welcome you to join the 2nd International Conference on Pediatrics and Child Health, scheduled for May 07–08, 2026, in Kuala Lumpu...
2nd International Conference on Pediatrics and Child Health We are cordially welcome you to join the 2nd International Conference on ...
2nd International Conference on Pediatrics and Child Health We are cordially welcome you to join the 2nd Int...
07 - 08 May 2026
Kuala Lumpur, Malaysia
JUN
18
ENVSCIRES 2026
International Conference on Environmental Science and Research We warmly invite you to join EnviWorld 2026 – the International Conference on Environmental Science and Research, taking place from June 18–20, 2026, in Barcelona, Spain, and accessible worldwide through an online platform...
International Conference on Environmental Science and Research We warmly invite you to join EnviWorld 2026 – the International Conference on Environmental Science and Research, taking place from June 18–20, 202...
International Conference on Environmental Science and Research We warmly invite you to join EnviWorld 2026 – the International Conferenc...
International Conference on Environmental Science and Research We warmly invite you to join EnviWorld 2026 – th...
18 - 20 Jun 2026
Barcelona, Spain
JUN
25
International Conference on Advanced Pulmonology, Respiratory Medicine & Lung Health- ICPRL 2026 Join global thought leaders at the International Conference on Advanced Pulmonology, Respiratory Medicine & Lung Health (ICPRL 2026), scheduled for June 25–27, 2026, in Barcelona, Spain and virtually. With the theme “Shapi...
International Conference on Advanced Pulmonology, Respiratory Medicine & Lung Health- ICPRL 2026 Join global thought leaders at the International Conference on Advanced Pulmonology, Respiratory Medicine & Lung Health (ICPRL 2026), scheduled for...
International Conference on Advanced Pulmonology, Respiratory Medicine & Lung Health- ICPRL 2026 Join global thought leaders at the International Conference on Advanced P...
25 - 27 Jun 2026
Barcelona, Spain
OCT
2
DAC2025
Diabetes Asia 2025 Conference "Diabetes Asia 2025" Conference aims to help improve the management of diabetes with emphasis on recent advances and practical aspects of diabetes care. The conference covers the wide-ranging issues in diabetes mellitus as...
Diabetes Asia 2025 Conference "Diabetes Asia 2025" Conference aims to help improve the management of diabetes with emphasis on recent advances and practical aspects of diabetes ...
Diabetes Asia 2025 Conference "Diabetes Asia 2025" Conference aims to help improve the management of di...
Diabetes Asia 2025 Conference "Diabetes Asia 2025" Conference aims to help imp...
02 - 04 Oct 2025
Kuala Lumpur, Malaysia