Search

Indoor climate control is a central topic in modern buildings. Especially office spaces have to provide a high comfort for the occupants while at the same time the building operation should require as little energy as possible. Moreover, an upcoming topic in building automation is a fast reaction to user feedback. The traditional design of a room temperature controller focuses solely on a good rejection of input disturbances such as variations of occupancy and solar radiation. Since the transfer functions of the user feedback and the input disturbances to the room temperature differ, a fast reaction to user feedback requires rethinking the design of a room temperature controller. Altogether, there is a desire to use modern controllers for room temperature control.

TH17 cells are major drivers of inflammation and involved in several autoimmune diseases. Tissue inflammation is a beneficial host response to infection, but it can also contribute to autoimmunity. The crosstalk between a tissue and the immune system during an inflammatory response is key for preserving tissue integrity and restoring physiological processes. However, how the inflamed tissue regulates the magnitude of an immune response by controlling pro-inflammatory T cells is not well characterized so far. Here we show that TH17 cells accumulating in the small intestine upon inflammation express the IL-33 receptor (ST2) and intestinal epithelial cells (IEC) are the main source of the alarmin interleukin-33 (IL-33). We show that pro-inflammatory TH17 cells acquire a regulatory phenotype with immunosuppressive properties in response to IL-33. Absence of ST2 signaling promotes the secretion of pro-inflammatory cytokines by TH17 cells and dampens the secretion of IL-10. Our results provide new insights into the mechanisms by which IEC, via IL-33/ST2 axis, may control pro-inflammatory TH17 cells in the small intestine to sustain homeostasis.

TH17 cells are major drivers of inflammation and involved in several autoimmune diseases. Tissue inflammation is a beneficial host response to infection, but it can also contribute to autoimmunity. The crosstalk between a tissue and the immune system during an inflammatory response is key for preserving tissue integrity and restoring physiological processes. However, how the inflamed tissue regulates the magnitude of an immune response by controlling pro-inflammatory T cells is not well characterized so far. Here we show that TH17 cells accumulating in the small intestine upon inflammation express the IL-33 receptor (ST2) and intestinal epithelial cells (IEC) are the main source of the alarmin interleukin-33 (IL-33). We show that pro-inflammatory TH17 cells acquire a regulatory phenotype with immunosuppressive properties in response to IL-33. Absence of ST2 signaling promotes the secretion of pro-inflammatory cytokines by TH17 cells and dampens the secretion of IL-10. Our results provide new insights into the mechanisms by which IEC, via IL-33/ST2 axis, may control pro-inflammatory TH17 cells in the small intestine to sustain homeostasis.

The transcription factor T-bet is highly expressed by Th cells isolated from the inflamed intestine of Crohn’s disease patients, and has been regarded a critical driver of murine T cell-induced colitis. However, we show here that T-bet expression by Th cells is not required for the manifestation of T-cell-induced colitis in the presence of segmented filamentous bacteria and Helicobacter hepaticus. T-bet expression by Th cells controls their survival and localization, their repertoire of chemokine and chemokine receptor expression, the accumulation of monocytes and macrophages in the inflamed colon, and their differentiation to the M1 type, i.e., type 1 inflammation. Nevertheless, T-bet-deficient Th cells efficiently induce colitis, as reflected by weight loss, diarrhea, and colon histopathology. T-bet-deficient Th cells differentiate into Th1/17 cells, able to express IFN-γ and IL-17A upon restimulation. While neutralization of IL-17A exacerbated colitis induced by wild-type or T-bet-deficient Th cells, neutralization of IFN-γ completely abolished colitis.

The transcription factor T-bet is highly expressed by Th cells isolated from the inflamed intestine of Crohn's disease patients, and has been regarded a critical driver of murine T cell-induced colitis. However, we show here that T-bet expression by Th cells is not required for the manifestation of T-cell-induced colitis in the presence of segmented filamentous bacteria and Helicobacter hepaticus. T-bet expression by Th cells controls their survival and localization, their repertoire of chemokine and chemokine receptor expression, the accumulation of monocytes and macrophages in the inflamed colon, and their differentiation to the M1 type, i.e., type 1 inflammation. Nevertheless, T-bet-deficient Th cells efficiently induce colitis, as reflected by weight loss, diarrhea, and colon histopathology. T-bet-deficient Th cells differentiate into Th1/17 cells, able to express IFN-γ and IL-17A upon restimulation. While neutralization of IL-17A exacerbated colitis induced by wild-type or T-bet-deficient Th cells, neutralization of IFN-γ completely abolished colitis.

Recent studies have shown that persistent specific antibody titer is provided by long-lived plasma cells (PC) which constitute a new kind of 'memory-providing cells'. In the present study, we examine the role of antigen for the long-term survival of PC and the maintenance of specific serum antibody titers. Using a novel cytometric technology, to identify and isolate antigen-specific PC, we analyzed long-lived PC of BALB/c mice, during their development (between day 1 and 10) after secondary immunization with ovalbumin (OVA) and in the phase of the established immune reaction. Most if not all OVA-specific PC were generated within a few days after immunization. Within 3 weeks, they matured, as indicated by down-regulation of expression of MHC class II. These PC are long lived and located in spleen and bone marrow. Upon adoptive transfer, OVA-specific PC from bone marrow, but not memory B cells, conferred specific and long-lasting antibody titers to antigen-free IgH syngeneic recipients. In response to antigenic challenge, new OVA-specific antibody-secreting cells were generated from transferred memory B cells. Antibody secretion by long-lived PC was not affected. Our results confirm that persistent antibody titers are provided by long-lived PC, independent of memory B cells and demonstrate that this humoral memory is inert to antigen.
Keywords:antibody-secreting cell, cellular-affinity matrix, humoral memory, serum antibody titer

Recent studies have shown that persistent specific antibody titer is provided by long-lived plasma cells (PC) which constitute a new kind of 'memory-providing cells'. In the present study, we examine the role of antigen for the long-term survival of PC and the maintenance of specific serum antibody titers. Using a novel cytometric technology, to identify and isolate antigen-specific PC, we analyzed long-lived PC of BALB/c mice, during their development (between day 1 and 10) after secondary immunization with ovalbumin (OVA) and in the phase of the established immune reaction. Most if not all OVA-specific PC were generated within a few days after immunization. Within approximately 3 weeks, they matured, as indicated by down-regulation of expression of MHC class II. These PC are long lived and located in spleen and bone marrow. Upon adoptive transfer, OVA-specific PC from bone marrow, but not memory B cells, conferred specific and long-lasting antibody titers to antigen-free IgH syngeneic recipients. In response to antigenic challenge, new OVA-specific antibody-secreting cells were generated from transferred memory B cells. Antibody secretion by long-lived PC was not affected. Our results confirm that persistent antibody titers are provided by long-lived PC, independent of memory B cells and demonstrate that this humoral memory is inert to antigen.