Navigation Links
Natural (born) killers: What do they really do?

Our immune systems contain three fundamentally different types of cell: B-cells, T-cells and the mysteriously named Natural Killer cells (NK cells), which are known to be involved in killing tumour cells and other infected cells. Experiments to investigate the function of NK cells have proven difficult to interpret because the interactions between the various components of the immune system make it almost impossible to isolate effects of individual cell types. This has changed with the development of a mouse in which individual genes can be knocked out (eliminated) only in NK cells, thereby providing scientists with a tool to study the importance of NK cells and indeed of individual pathways in these cells. The mouse was generated in the group of Veronika Sexl, who has recently moved from the Medical University of Vienna to the University of Veterinary Medicine, Vienna. An initial characterization is presented in the current issue of the journal Blood.

The development of a tool alone would not normally generate headlines but this case is different: the new mouse can be used to knock out any gene completely and exclusively in NK cells. It thus permits researchers to examine the functions of NK cells in the entire organism or even to investigate the importance of individual genes in this particular cell-type.

Sexl herself has naturally used the tool already. She has been able to show that a particular transcription factor known as Stat5 is essential for the correct development of NK cells when this factor is eliminated, the cells fail to develop properly. The upshot is a mouse with an immune system that lacks NK cells but is otherwise fully intact. This is the first time it has proven possible to remove this particular cell type without affecting the rest of the animal. Finally, then, it is possible to learn what NK cells actually do in the intact organism.

Sexl and her collaborators have shown that mice lacking NK cells have normal T-cell responses to tumours, although their NK cell-mediated responses are naturally dramatically reduced. This experiment proves conclusively that the mouse can be used to untangle the web of interactions among the various cells of the immune system.

Sexl's work has immediate implications for the treatment of cancer in humans. As an example, leukemia is sometimes treated by inhibiting the STAT5 protein. Sexl's findings make it clear that this approach has a real drawback: inhibition of STAT5 will lead to a drop in the number of NK cells and so interfere with one of the body's own mechanisms for fighting the cancer. It will be important to assess whether NK cells normally play a part in fighting diseases before inhibiting STAT5. For the first time, the newly developed mouse provides a tool to do so. Not surprisingly, it is already attracting a great deal of interest as Sexl says, "They've been going like hot cakes ever since the word got out."


Contact: Prof. Veronika Sexl
University of Veterinary Medicine -- Vienna

Related biology news :

1. Discovery of natural compounds that could slow blood vessel growth
2. Design of a compound that stabilizes the main natural suppressor of tumors
3. International Council for Science launches major research program on natural disasters
4. Natural and social sciences: ICSU embraces the need to work more closely together
5. Ecologists say metabolism accounts for why natural selection favors only some species
6. Natural Capital Project to develop conservation software
7. Honey adds health benefits, is natural preservative and sweetener in salad dressings
8. New research shows how gene function drives natural selection in important class of genetic elements
9. Apolipoprotein(a): A natural regulator of inflammation
10. Grape-seed extract kills laboratory leukemia cells, proving value of natural compounds
11. Particulate emission from natural gas burning home appliances
Post Your Comments:
(Date:11/12/2015)... Nov. 12, 2015  A golden retriever that stayed ... dystrophy (DMD) has provided a new lead for treating ... the Broad Institute of MIT and Harvard and the ... . Cell, pinpoints a protective ... the disease,s effects. The Boston Children,s lab of ...
(Date:11/10/2015)... , Nov. 10, 2015  In this ... the basis of product, type, application, disease ... in this report are consumables, services, software. ... are safety biomarkers, efficacy biomarkers, and validation ... report are diagnostics development, drug discovery and ...
(Date:11/4/2015)... York , November 4, 2015 ... a new market report published by Transparency Market Research "Home ... Growth, Trends and Forecast 2015 - 2022", the global home ... US$ 30.3 bn by 2022. The market is estimated ... forecast period from 2015 to 2022. Rising security needs ...
Breaking Biology News(10 mins):
(Date:11/24/2015)...  PDL BioPharma, Inc. (PDL) (NASDAQ: PDLI ) today ... and chief executive officer, will present at the 27 th ... New York City . The presentation will be ... at 9:30 a.m. EST. and go ... least 15 minutes prior to the presentation to allow for ...
(Date:11/24/2015)... (PRWEB) , ... November 24, 2015 , ... Whitehouse Laboratories ... Laboratory. The new stand-alone facility will be strictly dedicated to basic USP 61, ... and existing clients the chance to have complete chemistry and micro testing performed by ...
(Date:11/23/2015)... with a certain type of lung nodule visible on lung ... cancer than men with similar nodules, according to a new ... the Radiological Society of North America ... Lung nodules are small masses of tissue in the lungs ... appearance on CT. Solid nodules are dense, and they obscure ...
(Date:11/23/2015)... Nov. 23, 2015 China Cord Blood Corporation ... leading provider of cord blood collection, laboratory testing, hematopoietic ... announced its preliminary unaudited financial results for the second ... September 30, 2015. --> ... , Revenues for the second quarter of fiscal 2016 ...
Breaking Biology Technology: