Re: DAVID (allergies, autoimmune disease and hygeine)

[Guest guest]

Thanks athan. Researchers know now how to turn Tregs into Th17

cells:

J Immunother. 2009 February/March;32(2):101-108.

Interleukin 2-mediated Conversion of Ovarian Cancer-associated CD4+

Regulatory T Cells Into Proinflammatory Interleukin 17-producing

Helper T Cells.

Leveque L, Deknuydt F, Bioley G, Old LJ, Matsuzaki J, Odunsi K,

Ayyoub M, Valmori D

*Institut National de la Santé et de la Recherche Médicale, CLCC René

Gauducheau, Saint Herblain section signFaculty of Medicine,

University of Nantes, Nantes, France daggerLudwig Institute for

Cancer Research, New York Branch at Memorial Sloan Kettering Cancer

Center double daggerDepartment of Gynecologic Oncology and

Immunology, Roswell Park Cancer Institute, Buffalo, NY.

Epithelial ovarian cancer (EOC) is a highly inflammatory malignancy,

characterized by the presence, at the tumor site, of regulatory T

cells (Treg) that suppress antitumor immunity. Recently, a new

lineage of CD4 T cells producing the proinflammatory cytokine

interleukin (IL)-17 [T helper (TH) 17] has been identified as a major

player in some autoimmune diseases. The role of TH17 cells in cancer,

however, and their relationship with coexisting Treg populations,

whose differentiation is partially controlled by the same mediators

(ie, transforming growth factor-beta), are yet unclear. Here, we show

that EOC-associated/infiltrating lymphocytes derived by culturing

tumor samples in the presence of IL-2 contain significant frequencies

of TH17 cells, coproducing interferon-gamma (IFN)-gamma and tumor

necrosis factor (TNF)-alpha, which represent, in some cases, up to

40% of total CD4 T cells. TH17 cells were also detected ex vivo, but

at lower proportions than in cultured tumor-infiltrating

lymphocytes/tumor-associated lymphocytes, and were confined to the

CD4CD25 fraction. Remarkably, analysis of EOC-associated conventional

CD4CD25 T cell and Treg populations isolated ex vivo from tumor

samples by cell sorting and cultured with tumor-associated CD3 cells

in the presence of IL-2 revealed that EOC Treg stimulated under these

conditions were rapidly converted into TH17 cells, down-regulated

FOXP3 expression, and lost their suppressive capacity. Thus, although

the impact of TH17 cells on the evolution of EOC remains to be

established, our data suggest that local IL-2 treatment in ovarian

cancer may result in the conversion of tumor-associated Treg into

TH17 cells, relieve Treg-mediated suppression, and contribute to

enhance antitumor immunity. PMID: 19238008.

and so, I don't think it will be too long before they figure out how

to do the reverse.

Best regards,

Dave R.

> It occurred to me that if we could figure out how the cancer

cells manage to do this, then maybe we could restore the balance in

these other diseases and allergies by converting some of the T cells

to Treg cells.