Humidity-regulated CLCA2 protects the epidermis from hyperosmotic stress

ISSN:1946-6234ISSN:1946-624

Humidity-regulated CLCA2 protects the epidermis from hyperosmotic stress

Low environmental humidity aggravates symptoms of the inflammatory skin disease atopic dermatitis (AD). Using mice that develop AD-like signs, we show that an increase in environmental humidity rescues their cutaneous inflammation and associated epidermal abnormalities. Quantitative proteomics analysis of epidermal lysates of mice kept at low or high humidity identified humidity-regulated proteins, including chloride channel accessory 3A2 (CLCA3A2), a protein with previously unknown function in the skin. The epidermis of patients with AD, organotypic skin cultures under dry conditions, and cultured keratinocytes exposed to hyperosmotic stress showed up-regulation of the nonorthologous human homolog CLCA2. Hyperosmolarity-induced CLCA2 expression occurred via p38/c-Jun N-terminal kinase–activating transcription factor 2 signaling. CLCA2 knockdown promoted keratinocyte apoptosis induced by hyperosmotic stress through impairment of cell-cell adhesion. These findings provide a mechanistic explanation for the beneficial effect of high environmental humidity for AD patients and identify CLCA3A2/CLCA2 up-regulation as a mechanism to protect keratinocytes from damage induced by low humidity

A novel three-dimensional heterotypic spheroid model for the assessment of the activity of cancer immunotherapy agents

The complexity of the tumor microenvironment is difficult to mimic in vitro, particularly regarding tumor–host interactions. To enable better assessment of cancer immunotherapy agents in vitro, we developed a three-dimensional (3D) heterotypic spheroid model composed of tumor cells, fibroblasts, and immune cells. Drug targeting, efficient stimulation of immune cell infiltration, and specific elimination of tumor or fibroblast spheroid areas were demonstrated following treatment with a novel immunocytokine (interleukin-2 variant; IgG-IL2v) and tumor- or fibroblast-targeted T cell bispecific antibody (TCB). Following treatment with IgG-IL2v, activation of T cells, NK cells, and NKT cells was demonstrated by increased expression of the activation marker CD69 and enhanced cytokine secretion. The combination of TCBs with IgG-IL2v molecules was more effective than monotherapy, as shown by enhanced effects on immune cell infiltration; activation; increased cytokine secretion; and faster, more efficient elimination of targeted cells. This study demonstrates that the 3D heterotypic spheroid model provides a novel and versatile tool for in vitro evaluation of cancer immunotherapy agents and allows for assessment of additional aspects of the activity of cancer immunotherapy agents, including analysis of immune cell infiltration and drug targeting.ISSN:0340-7004ISSN:1432-085

A novel three-dimensional heterotypic spheroid model for the assessment of the activity of cancer immunotherapy agents

The complexity of the tumor microenvironment is difficult to mimic in vitro, particularly regarding tumor–host interactions. To enable better assessment of cancer immunotherapy agents in vitro, we developed a three-dimensional (3D) heterotypic spheroid model composed of tumor cells, fibroblasts, and immune cells. Drug targeting, efficient stimulation of immune cell infiltration, and specific elimination of tumor or fibroblast spheroid areas were demonstrated following treatment with a novel immunocytokine (interleukin-2 variant; IgG-IL2v) and tumor- or fibroblast-targeted T cell bispecific antibody (TCB). Following treatment with IgG-IL2v, activation of T cells, NK cells, and NKT cells was demonstrated by increased expression of the activation marker CD69 and enhanced cytokine secretion. The combination of TCBs with IgG-IL2v molecules was more effective than monotherapy, as shown by enhanced effects on immune cell infiltration; activation; increased cytokine secretion; and faster, more efficient elimination of targeted cells. This study demonstrates that the 3D heterotypic spheroid model provides a novel and versatile tool for in vitro evaluation of cancer immunotherapy agents and allows for assessment of additional aspects of the activity of cancer immunotherapy agents, including analysis of immune cell infiltration and drug targeting. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00262-016-1927-1) contains supplementary material, which is available to authorized users