scholarly journals Characterization of the B Lymphocyte Populations in Lyn-Deficient Mice and the Role of Lyn in Signal Initiation and Down-Regulation

Immunity ◽  
1997 ◽  
Vol 7 (1) ◽  
pp. 69-81 ◽  
Author(s):  
Vivien W.F Chan ◽  
Fanying Meng ◽  
Philippe Soriano ◽  
Anthony L DeFranco ◽  
Clifford A Lowell
Keyword(s):  
B Lymphocyte ◽  
Down Regulation ◽  
Lymphocyte Populations ◽  
Deficient Mice

scholarly journals Characterization of Incidentally Identified Minute Clonal B-Lymphocyte Populations in Peripheral Blood and Bone Marrow

2004 ◽  
Vol 122 (4) ◽  
pp. 588-595 ◽  
Author(s):  
Weina Chen ◽  
Sheryl L. Asplund ◽  
Robert W. McKenna ◽  
Steven H. Kroft
Keyword(s):  
Bone Marrow ◽  
Peripheral Blood ◽  
B Lymphocyte ◽  
Lymphocyte Populations

Characterization of connexin30.3-deficient mice suggests a possible role of connexin30.3 in olfaction

2007 ◽  
Vol 86 (11-12) ◽  
pp. 683-700 ◽  
Author(s):  
Qingyi Zheng-Fischhöfer ◽  
Marc Schnichels ◽  
Ekrem Dere ◽  
Jörg Strotmann ◽  
Nadine Loscher ◽  
...  
Keyword(s):  
Deficient Mice

Human homologues of Delta-1 and Delta-4 function as mitogenic regulators of primitive human hematopoietic cells

Blood ◽  
2001 ◽  
Vol 97 (7) ◽  
pp. 1960-1967 ◽  
Author(s):  
Francis N. Karanu ◽  
Barbara Murdoch ◽  
Tomoyuki Miyabayashi ◽  
Mitsuhara Ohno ◽  
Masahide Koremoto ◽  
...  
Keyword(s):  
Cell Fate ◽  
Hematopoietic Cells ◽  
Functional Roles ◽  
Cell Fate Decisions ◽  
Wide Range ◽  
Deficient Mice

Delta-mediated Notch signaling controls cell fate decisions during invertebrate and murine development. However, in the human, functional roles for Delta have yet to be described. This study reports the characterization of Delta-1 and Delta-4 in the human. Human Delta-4 was found to be expressed in a wide range of adult and fetal tissues, including sites of hematopoiesis. Subsets of immature hematopoietic cells, along with stromal and endothelial cells that support hematopoiesis, were shown to express Notch and both Delta-1 and Delta-4. Soluble forms of human Delta-1 (hDelta-1) and hDelta-4 proteins were able to augment the proliferation of primitive human hematopoietic progenitors in vitro. Intravenous transplantation of treated cultures into immune-deficient mice revealed that hDelta-1 is capable of expanding pluripotent human hematopoietic repopulating cells detected in vivo. This study provides the first evidence for a role of Delta ligands as a mitogenic regulator of primitive hematopoietic cells in the human.

scholarly journals Myeloid cells, BAFF, and IFN-γ establish an inflammatory loop that exacerbates autoimmunity in Lyn-deficient mice

2010 ◽  
Vol 207 (8) ◽  
pp. 1757-1773 ◽  
Author(s):  
Patrizia Scapini ◽  
Yongmei Hu ◽  
Ching-Liang Chu ◽  
Thi-Sau Migone ◽  
Anthony L. DeFranco ◽  
...  
Keyword(s):  
T Cells ◽  
B Cell ◽  
B Lymphocyte ◽  
Myeloid Cells ◽  
Myeloid Cell ◽  
Cell Clones ◽  
B Lymphocyte Stimulator ◽  
Ifn Γ ◽  
Deficient Mice

Autoimmunity is traditionally attributed to altered lymphoid cell selection and/or tolerance, whereas the contribution of innate immune cells is less well understood. Autoimmunity is also associated with increased levels of B cell–activating factor of the TNF family (BAFF; also known as B lymphocyte stimulator), a cytokine that promotes survival of self-reactive B cell clones. We describe an important role for myeloid cells in autoimmune disease progression. Using Lyn-deficient mice, we show that overproduction of BAFF by hyperactive myeloid cells contributes to inflammation and autoimmunity in part by acting directly on T cells to induce the release of IFN-γ. Genetic deletion of IFN-γ or reduction of BAFF activity, achieved by either reducing myeloid cell hyperproduction or by treating with an anti-BAFF monoclonal antibody, reduced disease development in lyn−/− mice. The increased production of IFN-γ in lyn−/− mice feeds back on the myeloid cells to further stimulate BAFF release. Expression of BAFF receptor on T cells was required for their full activation and IFN-γ release. Overall, our data suggest that the reciprocal production of BAFF and IFN-γ establishes an inflammatory loop between myeloid cells and T cells that exacerbates autoimmunity in this model. Our findings uncover an important pathological role of BAFF in autoimmune disorders.

scholarly journals B Lymphocyte-Deficiency in Mice Causes Vascular Dysfunction by Inducing Neutrophilia

Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1686
Author(s):  
Ning Xia ◽  
Solveig Hasselwander ◽  
Gisela Reifenberg ◽  
Alice Habermeier ◽  
Ellen I. Closs ◽  
...  
Keyword(s):  
B Cell ◽  
B Lymphocytes ◽  
Vascular Function ◽  
B Lymphocyte ◽  
Vascular Dysfunction ◽  
Vascular Pathology ◽  
Neutrophil Depletion ◽  
B Cell Deficiency ◽  
Deficient Mice

B lymphocytes have been implicated in the development of insulin resistance, atherosclerosis and certain types of hypertension. In contrast to these studies, which were performed under pathological conditions, the present study provides evidence for the protective effect of B lymphocytes in maintaining vascular homeostasis under physiological conditions. In young mice not exposed to any known risk factors, the lack of B cells led to massive endothelial dysfunction. The vascular dysfunction in B cell-deficient mice was associated with an increased number of neutrophils in the circulating blood. Neutrophil depletion in B cell-deficient mice resulted in the complete normalization of vascular function, indicating a causal role of neutrophilia. Moreover, vascular function in B cell-deficient mice could be restored by adoptive transfer of naive B-1 cells isolated from wild-type mice. Interestingly, B-1 cell transfer also reduced the number of neutrophils in the recipient mice, further supporting the involvement of neutrophils in the vascular pathology caused by B cell-deficiency. In conclusion, we report in the present study the hitherto undescribed role of B lymphocytes in regulating vascular function. B cell dysregulation may represent a crucial mechanism in vascular pathology.

scholarly journals Immunomodulation of Homeopathic Thymulin 5CH in a BCG-Induced Granuloma Model

2013 ◽  
Vol 2013 ◽  
pp. 1-15 ◽  
Author(s):  
Leoni Villano Bonamin ◽  
Cesar Sato ◽  
Ruggero Zalla Neto ◽  
Graziela Morante ◽  
Thayná Neves Cardoso ◽  
...  
Keyword(s):  
Lymph Node ◽  
Immune Modulation ◽  
B Lymphocyte ◽  
Treg Cells ◽  
Vehicle Control ◽  
Phenotypic Characterization ◽  
Male Adult ◽  
Local Lymph Node ◽  
Lymphocyte Populations

The present study analyzed the immune modulation mechanisms of thymulin 5CH in a granuloma experimental model. Male adult Balb/c mice were inoculated with BCG into the footpad to induce granuloma, which was quantitatively evaluated. The phenotypic characterization of phagocyte, T- and B-lymphocyte populations in the peritoneum, and local lymph node was done by flow cytometry. During all experimental periods, thymulin 5CH and vehicle (control) were givenad libitumto mice, diluted into the drinking water (1.6×10−17 M). After 7 days from inoculation, thymulin-treated mice presented reduction in the number of epithelioid cytokeratine-positive cells (P=0.0001) in the lesion, in relation to young phagocytes. After 21 days, the differentiation of B1 peritoneal stem cells into phagocytes reached the peak, being higher in thymulin-treated mice (P=0.0001). Simultaneously, the score of infected phagocytes in the lesion decreased (P=0.001), and the number of B1-derived phagocytes, CD4+ and CD8+ T lymphocytes in the local lymph node increased in relation to control (P=0.0001). No difference was seen on the CD25+ Treg cells. The results show that thymulin 5CH treatment is able to improve the granuloma inflammatory process and the infection remission, by modulating local and systemic phagocyte differentiation.

Human homologues of Delta-1 and Delta-4 function as mitogenic regulators of primitive human hematopoietic cells

Blood ◽  
2001 ◽  
Vol 97 (7) ◽  
pp. 1960-1967 ◽  
Author(s):  
Francis N. Karanu ◽  
Barbara Murdoch ◽  
Tomoyuki Miyabayashi ◽  
Mitsuhara Ohno ◽  
Masahide Koremoto ◽  
...  
Keyword(s):  
Cell Fate ◽  
Hematopoietic Cells ◽  
Functional Roles ◽  
Cell Fate Decisions ◽  
Wide Range ◽  
Deficient Mice

Abstract Delta-mediated Notch signaling controls cell fate decisions during invertebrate and murine development. However, in the human, functional roles for Delta have yet to be described. This study reports the characterization of Delta-1 and Delta-4 in the human. Human Delta-4 was found to be expressed in a wide range of adult and fetal tissues, including sites of hematopoiesis. Subsets of immature hematopoietic cells, along with stromal and endothelial cells that support hematopoiesis, were shown to express Notch and both Delta-1 and Delta-4. Soluble forms of human Delta-1 (hDelta-1) and hDelta-4 proteins were able to augment the proliferation of primitive human hematopoietic progenitors in vitro. Intravenous transplantation of treated cultures into immune-deficient mice revealed that hDelta-1 is capable of expanding pluripotent human hematopoietic repopulating cells detected in vivo. This study provides the first evidence for a role of Delta ligands as a mitogenic regulator of primitive hematopoietic cells in the human.

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