ORCID Profile
0000-0002-4477-3932
Current Organisations
Swedish International Development Cooperation Agency
,
Karolinska Institutet
,
University of North Carolina at Chapel Hill
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Public Library of Science (PLoS)
Date: 12-10-2010
Publisher: Informa UK Limited
Date: 22-10-2009
Publisher: Cambridge University Press (CUP)
Date: 09-09-2011
DOI: 10.1017/S0031182011001363
Abstract: NK cells represent one of the first lines of defence in the immune reaction after invasion of Leishmania parasites. Depletion of mouse natural killer (NK) cells dramatically enhances susceptibility of normally resistant mice. In this study we evaluated the fate of NK cells and parasites after contact formation. The hydrophilic fluorescent dye CMFDA (chloro-methylfluorescin diacetate) that allows analysis of cytotoxicity in flow cytometry and microscopy was used. Furthermore, these findings were confirmed with scanning and transmission electron microscopy. Direct contact points were found between Leishmania promastigotes and naïve human NK cells. These contacts were associated with transfer of cytosol by membrane bridges and cytotoxicity of NK cells against Leishmania . However, in contrast to other target cells which allow repeated exocytosis of lytic granules, contact with Leishmania causes immediate destruction of NK cells in a non-apoptotic way. Our results give a reasonable explanation for ex vivo observations of reduced NK cell numbers and impaired NK response in patients with acute cutaneous leishmaniasis. Animal models have clearly shown that NK cells play a key role in the induction and direction of the immune response. Thus inhibition of NK cells at the onset of infection would be advantageous for the survival of the parasite.
Publisher: Oxford University Press (OUP)
Date: 11-07-2008
DOI: 10.1111/J.1365-2249.2008.03687.X
Abstract: Natural killer (NK) cells contribute to immunity as the first line of defence in numerous infections by early cytokine secretion and cytotoxicity. In Leishmania infection, NK cells contribute with interferon-γ and may assist in directing the immune response towards T helper type 1, which is essential for successful control of the parasites. Thus, NK cells may play an important role in both resistance and control of the infection. However, during Leishmania infection NK cells show signs of suppression. To explore the reason for this suppression, we exposed naive and interleukin (IL)-2 activated NK cells directly to promastigotes of Leishmania major in vitro. As a rapid consequence of contact between naive NK cells and promastigotes, expression of NK cell receptors show significant changes. We identify one of the major surface molecules of promastigotes, glycoprotein (gp) 63, as an important agent for these suppressive effects by using promastigotes of a gp63ko strain of L. major. Furthermore, proliferation of IL-2-activated purified NK cells is suppressed after exposure to the wild-type but not to gp63ko promastigotes. However, gp63ko L. major induced no NK cell proliferation when NK cells were co-cultured with peripheral blood mononuclear cells populations such as CD14+ monocytes or T cells.
Publisher: Elsevier BV
Date: 2007
Publisher: Elsevier BV
Date: 11-2006
DOI: 10.1016/J.VACCINE.2006.05.016
Abstract: In the screening of vaccine candidates it is important to select candidates that evoke immune responses associated with protection. Valid surrogate markers against human leishmaniasis are still lacking. A controlled injection of live Leishmania known as leishmanization, (LZ), was used to evaluate vaccine (alum-precipitated autoclaved Leishmania major with BCG) efficacy and more accurately define surrogate markers of immunity to leishmaniasis in humans. Cellular immune responses to this artificial infection were monitored in the volunteers prior to and 9 months post infection. Comparisons were made between those who developed a lesion after infection and those who did not. In the volunteers monitored there was no significant difference in LST, IFNgamma production, or source of IFNgamma between those who developed a lesion and those who did not after LZ, with the exception that ulcer development was associated with an enhanced number of IFNgamma secreting CD4(+) CD45RA(-) (memory) T cells. Ulcer development following LZ was lower than anticipated by a pilot study (47% versus 78%) using the same stabilate several years earlier. While this may be an effect of low viability/virulence of the LZ inocula, alternative explanations are also possible. The IFNgamma responses in the study subjects were significantly lower compared to volunteers with previous history of cutaneous leishmaniasis. The findings raise the possibility that the selection of LST-negative volunteers in an endemic area may bias the study towards potentially non/low L. major-reactive volunteers.
Publisher: Elsevier BV
Date: 06-2015
DOI: 10.1016/J.AJOG.2015.02.017
Abstract: The purpose of this study was to report the rates and types of pelvic organ prolapse (POP) and female continence surgery performed in member countries of the Organization for Economic Co-operation and Development (OECD) in 2012. The published health outcome data sources of the 34 OECD countries were contacted for data on POP and female continence interventions from 2010-2012. In nonresponding countries, data were sought from national or insurer databases. Extracted data were entered into an age-specific International Classification of Disease, edition 10 (ICD-10)-compliant Excel spreadsheet by 2 authors independently in English-speaking countries and a single author in non-English-speaking countries. Data were collated centrally and discrepancies were resolved by mutual agreement. We report on 684,250 POP and 410,352 continence procedures that were performed in 15 OECD countries in 2012. POP procedures (median rate, 1.38/1000 women range, 0.51-2.55 prolapse procedures/1000 women) were performed 1.8 times more frequently than continence procedures (median rate, 0.75/1000 women range, 0.46-1.65 continence procedures/1000 women). Repairs of the anterior vaginal compartment represented 54% of POP procedures posterior repairs represented 43% of the procedures, and apical compartment repairs represented 20% of POP procedures. Median rate of graft usage was 15.7% of anterior vaginal repairs (range, 3.3-25.6%) and 8.5% (range, 3.2-17%) of posterior vaginal repairs. Apical compartment repairs were repaired vaginally at a median rate of 70% (range, 35-95%). Sacral colpopexy represented a median rate of 17% (range, 5-65%) of apical repairs 61% of sacral colpopexies were performed minimally invasively. Between 2010 and 2012, there was a 3.7% median reduction in transvaginal grafts, a 4.0% reduction in midurethral slings, and a 25% increase in sacral colpopexies that were performed per 1000 women. Midurethral slings represented 82% of female continence surgeries. The 5-fold variation in the rate of prolapse interventions within OECD countries needs further evaluation. The significant heterogeneity (>10 times) in the rates at which in idual POP procedures are performed indicates a lack of uniformity in the delivery of care to women with POP and demands the development of uniform guidelines for the surgical management of prolapse. In contrast, the midurethral slings were the standard female continence surgery performed throughout OECD countries in 2012.
Publisher: Elsevier BV
Date: 04-2005
Location: United States of America
Location: Sweden
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: United States of America
No related grants have been discovered for Jennifer Wu.