| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Akuffo, H, et al.
(författare)
-
Ivermectin-induced immunopotentiation in onchocerciasis: recognition of selected antigens following a single dose of ivermectin
- 1996
-
Ingår i: Clinical and experimental immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 103:2, s. 244-252
-
Tidskriftsartikel (refereegranskat)abstract
- Onchocerciasis is associated with blindness and gross skin changes, believed to be a consequence of the immune response to antigens released from the offspring of the female worm of Onchocerca volvulus, the microfilariae (mf). An effective microfilaricidal drug is now available which quickly reduces the mf burden without affecting the adult worm. There exist foci in onchocerciasis endemic areas where some of the patients have many mf in their skin but relatively few clinical symptoms. This state of hyposensitivity is believed to be due to immunosuppression. The aim of this study was to address the question of the basis of, and the effect of ivermectin treatment on this immunosuppression. Female adult worms of O. volvulus were used as whole or fractionated antigens to stimulate peripheral blood mononuclear cells. Microfilariae are found in the reproduction tract of the female worms, and thus an antigen preparation of the female adult O. volvulus contains both exclusive adult antigens as well as antigens from microfilariae. Cells were obtained from onchocerciasis patients, individuals of similar socio-economic status living in the same Ghanaian village, but who showed no parasitological or clinical evidence of onchocerciasis (exposed endemic controls), healthy Ghanaians living in areas where transmission of onchocerciasis does not seem to occur (non-exposed endemic controls) and unexposed healthy Swedish donors. As a group, cells from onchocerciasis patients proliferated to a lesser degree than cells from the exposed endemic control and the non-exposed endemic control groups to the whole worm antigen, whereas the phytohaemagglutinin (PHA) response was strongest in the patients. Proliferative responses of above 1000 ct/min to fractions of the worm extract were only evident in the cells from a few individuals in each of the various groups. However, 28 days following ivermectin treatment, cells from all onchocerciasis patients were able to mount significantly enhanced proliferation to a fraction of approximately 96 kD (fraction 3), while only four of nine of this group showed an increased response to the whole worm antigen. The proportional increase in the response to the whole organism in these individuals was of a much lower magnitude than the increased response to fraction 3. The O. volvulus antigen-specific immunosuppression observed in these onchocerciasis patients appears to be due to suppressive antigens which have the capacity to mask the potential response to selected antigens of O. volvulus, and ivermectin treatment possibly modulates the immune response, allowing for stepwise recognition of such antigens. Since ivermectin treatment kills only the microfilariae and not the adult worm, the putative suppressive antigens would be expected to be from the microfilariae.
|
|
| 8. |
|
|
| 9. |
- Akuffo, H, et al.
(författare)
-
Natural killer cells in cross-regulation of IL-12 by IL-10 in Leishmania antigen-stimulated blood donor cells
- 1999
-
Ingår i: Clinical and experimental immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 117:3, s. 529-534
-
Tidskriftsartikel (refereegranskat)abstract
- We have previously shown that natural killer (NK) cells play a role in protection against leishmaniasis. Furthermore, we have shown that NK cells in mononuclear cells derived from unexposed donors are induced to proliferate in vitro in response to leishmanial antigens. Since interleukin (IL)-12, a strong inducer of NK cells, acts on the early events in NK cells and T-cells, and is considered as an adjuvant for use in a potential antileishmaniasis antigen, we wished to investigate how this cytokine influences the in vitro Leishmania induced proliferative and cytokine response in healthy donors. We demonstrate that in an innate response to Leishmania antigen involving NK cells, a critical level of IL-12 is required to induce interferon (IFN)-γ secretion below which, IL-10 is released in amounts which apparently inhibit IFN-γ secretion and cellular proliferation. However, at higher IL-12 levels, there is simultaneous secretion of IFN-γ and IL-10 as well as proliferation of cells. In a similar vein, exogenous IL-10 in turn inhibited IFN-γ secretion as well as proliferation when used at low/medium concentrations, but at high concentrations this effect was abolished and replaced by the simultaneous detection of IFN-γ, IL-10 and proliferation. The contribution of NK cells in cross regulation of these two very important immuneregulatory cytokines and the effect of exogenous IL-12 in a Leishmania driven response are discussed.
|
|
| 10. |
|
|
| 11. |
- Akuffo, H, et al.
(författare)
-
Worms and Humans: A Happy Divorce?
- 2015
-
Ingår i: Forum on immunopathological diseases and therapeutics. - 2151-8017. ; 6:1-2, s. 27-32
-
Tidskriftsartikel (refereegranskat)
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
|
|
| 20. |
- Elias, D., et al.
(författare)
-
Schistosoma mansoni infection reduces the protective efficacy of BCG vaccination against virulent Mycobacterium tuberculosis
- 2005
-
Ingår i: Vaccine. - : Elsevier BV. - 0264-410X .- 1873-2518. ; 23:11, s. 1326-1334
-
Tidskriftsartikel (refereegranskat)abstract
- We hypothesized that the ability of BCG vaccination to protect against Mycobacterium tuberculosis is less in hosts exposed to chronic helminthes infection compared to unexposed individuals. To test this hypothesis we evaluated the efficacy of BCG vaccination in protecting against M. tuberculosis challenge in Schistosoma mansoni pre-infected mice by analyzing their ability to limit the replication of TB bacilli in the lung and liver and the histology of lung sections. The results show that BCG vaccinated mice with prior S. mansoni infection show significantly higher number of colony forming units of TB bacilli as well as significant reduction in air exchange area in the lung compared to controls. In addition, spleen cells from S. mansoni infected mice were found to produce significantly less IFN-? and nitric oxide when stimulated in vitro with PPD and several fold higher soluble egg antigen (SEA) and Concanavalin A induced IL-4 and IL-5 secretion. Taken together, our data show that S. mansoni infection reduces the protective efficacy of BCG vaccination against M. tuberculosis possibly by attenuation of protective immune responses to mycobacterial antigens and/or by polarizing the general immune responses to the Th2 profile. © 2004 Published by Elsevier Ltd.
|
|
| 21. |
|
|
| 22. |
|
|
| 23. |
|
|
| 24. |
|
|
| 25. |
|
|
| 26. |
|
|
| 27. |
- Montelius, S, et al.
(författare)
-
Skin rash for 15 years
- 1998
-
Ingår i: Lancet (London, England). - 0140-6736. ; 352:9138, s. 1438-1438
-
Tidskriftsartikel (refereegranskat)
|
|
| 28. |
|
|
| 29. |
|
|
| 30. |
- Nylen, S, et al.
(författare)
-
Tracing immunity to human leishmaniasis
- 2009
-
Ingår i: Future microbiology. - : Future Medicine Ltd. - 1746-0921 .- 1746-0913. ; 4:2, s. 241-254
-
Tidskriftsartikel (refereegranskat)abstract
- People who have recovered from leishmaniasis are believed to have long-lasting protection against subsequent infection. Understanding the immunological changes that are associated with protection from cure of and susceptibility to the disease are fundamental to both designing and evaluating vaccine candidates against the leishmaniases. In the quest for a vaccine against leishmaniasis, appropriate surrogate markers of immunity would be valuable and cost effective. Biomarkers would ease screening and selection of potentially efficient vaccine candidates. Moreover, biomarkers of disease may be used to monitor disease and aid therapeutic prognosis. This would be useful in the evaluation of both existing and new drugs, making invasive post-treatment evaluation redundant. Biomarkers may also be indicative of the severity of the disease and may be able to predict the outcome of an infection and indicate whether the patient will spontaneously recover, exhibit mild symptoms or if the disease is disseminating and will be severe. In this article we discuss the immunological changes associated with different forms of human leishmaniasis and the value of appropriate immunological biomarkers in finding an effective vaccine and an evaluation of therapies against leishmanial disease will be given.
|
|
| 31. |
|
|
| 32. |
|
|
| 33. |
|
|
| 34. |
|
|
| 35. |
- Wolday, D, et al.
(författare)
-
Emerging Leishmania/HIV co-infection in Africa
- 2001
-
Ingår i: Medical microbiology and immunology. - : Springer Science and Business Media LLC. - 0300-8584 .- 1432-1831. ; 190:1-2, s. 65-67
-
Tidskriftsartikel (refereegranskat)
|
|
| 36. |
|
|
| 37. |
|
|
| 38. |
|
|
| 39. |
|
|
