LDHA-Associated Lactic Acid Production Blunts Tumor Immunosurveillance by T and NK Cells.

Elevated lactate dehydrogenase A (LDHA) expression is associated with poor outcome in tumor patients. Here we show that LDHA-associated lactic acid accumulation in melanomas inhibits tumor surveillance by T and NK cells. In immunocompetent C57BL/6 mice, tumors with reduced lactic acid production (Ldha) developed significantly slower than control tumors and showed increased infiltration with IFN-γ-producing T and NK cells.

The complement receptors CD46, CD55 and CD59 are regulated by the tumour microenvironment of head and neck cancer to facilitate escape of complement attack.

Background: Membrane-bound complement restriction proteins (mCRPs) CD46, CD55 and CD59 enable tumour cells to evade complement dependent cytotoxicity and antibody-dependent killing mechanisms. But less is known about the role of these mCRPs in head and neck cancer.

Methods: In this study we determined the expression of the mCRPs on head and neck squamous cell carcinoma (HNSCC) cell lines, on tumour tissue and TDLNs (tumour-draining lymph nodes) as well as on lymphocytes from HNSCC patients.

Enhanced iodine supplementation alters the immune process in a transgenic mouse model for autoimmune thyroiditis.

Background: The impact of excessive iodine intake on the development of autoimmune thyroiditis (AIT) is still under debate. Transgenic, antibody-devoid TAZ10 mice spontaneously develop AIT due to autoreactive thyroperoxidase-specific T cells. In this model, development of AIT is determined by a T cell infiltration of the thyroid gland leading to an elevation of serum thyrotropin (TSH) levels and significant weight gain.

Immunoregulatory natural killer cells suppress autoimmunity by down-regulating antigen-specific CD8+ T cells in mice.

Natural killer (NK) cells belong to the innate immune system. Besides their role in antitumor immunity, NK cells also regulate the activity of other cells of the immune system, including dendritic cells, macrophages, and T cells, and may, therefore, be involved in autoimmune processes. The aim of the present study was to clarify the role of NK cells within this context.

Thalidomide has anti-inflammatory properties in neonatal immune cells.

Neonates demonstrate functional immaturity and dysregulation of immune responses leading to systemic inflammation and enhanced apoptosis of immune cells. Thalidomide has already been proven to differentially regulate immune responses and support anti-apoptosis in immunodeficiency syndromes. Thus, it was the aim of this study to evaluate the effects of thalidomide on the cytokine response and apoptosis of neonatal immune cells.

Evidence of a combined cytotoxic thyroglobulin and thyroperoxidase epitope-specific cellular immunity in Hashimoto's thyroiditis.

Context: Hashimoto's thyroiditis (HT) is a common autoimmune disease leading to thyroid destruction due to lymphocytic infiltration. Only rare data are available regarding the recognition of specific cellular antigens, e.g.

Plasmacytoid dendritic cell subpopulations in head and neck squamous cell carcinoma.

Human plasmacytoid dendritic cells (PDCs) are present in solid tumor tissue and metastatic cervical lymph nodes (CLN) in head and neck squamous cell carcinoma (HNSCC). We recently showed that classical PDC functions are heavily disturbed in the tumor microenvironment. In this study we present a new approach to the subject by introducing 3 PDC subsets in HNSCC, characterized by the surface markers CD25, CD56 and CD203c.

The number of CD161 positive Th17 cells are decreased in head and neck cancer patients.

Background: Despite lots of research efforts, the pathology of head and neck cancer remains elusive. Accumulating evidence suggests that the innate and adaptive immunity plays an important role in HNSCC (Head and Neck Squamous Cell Carcinoma) development. Recently, a new T helper cell subset additional to the classical Th1 and Th2 cells was identified called Th17 cells, due to their secretion of IL-17.

Expression of the T cell receptor αβ on a CD123+ BDCA2+ HLA-DR+ subpopulation in head and neck squamous cell carcinoma.

Human Plasmacytoid Dendritic Cells (PDCs) infiltrating solid tumor tissues and draining lymph nodes of Head and Neck Squamous Cell Carcinoma (HNSCC) show an impaired immune response. In addition to an attenuated secretion of IFN-α little is known about other HNSCC-induced functional alterations in PDCs. Particular objectives in this project were to gain new insights regarding tumor-induced phenotypical and functional alterations in the PDC population.

Effect of head and neck cancer supernatant and CpG-oligonucleotides on migration and IFN-alpha production of plasmacytoid dendritic cells.

Background: Plasmacytoid dendritic cells (PDCs) infiltrating solid tumor tissues and draining lymph nodes of head and neck squamous cell carcinoma (HNSCC) show an impaired immune response. Immunosuppressive cytokines secreted by HNSCC have been recognized to account for reduced interferon-alpha (IFN-alpha) production, whereas the influence on PDC migration has not yet been investigated.

Materials And Methods: PDCs were isolated from human peripheral blood by magnetic bead separation.

Secretion of tumor-promoting and immune suppressive cytokines by cell lines of head and neck squamous cell carcinoma.

Background: Cytokine profiles of permanent cell lines of head and neck squamous cell carcinoma (HNSCC) were analyzed to define the cytokine levels secreted in the absence of immune cells.

Materials And Methods: Cytokine profiles of IL-4, IL-6, IL-8 and IL-10 were analyzed in the supematants of 4 different permanent HNSCC cell lines using the Bio-Plex human cytokine assay system.

Results: In HNSCC, IL-6 and IL-8 are involved in oncogenic processes, while IL-4 and IL-10 suppress proper immune responses in the tumor microenvironment.