Uptake of Intravenously Administered Soluble Immune Complexes by Type I Alveolar Cells and Macrophages in Mice

1985 ◽  
Vol 78 (1) ◽  
pp. 108-111
Author(s):  
Y. Kanayama ◽  
K. Amatsu ◽  
N. Negoro ◽  
T. Takeda ◽  
T. Inoue
2006 ◽  
Vol 26 (3) ◽  
pp. 1109-1123 ◽  
Author(s):  
Daniela S. Bassères ◽  
Elena Levantini ◽  
Hongbin Ji ◽  
Stefano Monti ◽  
Shannon Elf ◽  
...  

ABSTRACT The leucine zipper family transcription factor CCAAT enhancer binding protein alpha (C/EBPα) inhibits proliferation and promotes differentiation in various cell types. In this study, we show, using a lung-specific conditional mouse model of C/EBPα deletion, that loss of C/EBPα in the respiratory epithelium leads to respiratory failure at birth due to an arrest in the type II alveolar cell differentiation program. This differentiation arrest results in the lack of type I alveolar cells and differentiated surfactant-secreting type II alveolar cells. In addition to showing a block in type II cell differentiation, the neonatal lungs display increased numbers of proliferating cells and decreased numbers of apoptotic cells, leading to epithelial expansion and loss of airspace. Consistent with the phenotype observed, genes associated with alveolar maturation, survival, and proliferation were differentially expressed. Taken together, these results identify C/EBPα as a master regulator of airway epithelial maturation and suggest that the loss of C/EBPα could also be an important event in the multistep process of lung tumorigenesis. Furthermore, this study indicates that exploring the C/EBPα pathway might have therapeutic benefits for patients with respiratory distress syndromes.


1981 ◽  
Vol 111 (2) ◽  
pp. 336-342 ◽  
Author(s):  
Bert W. Maidment ◽  
Lawrence D. Papsidero ◽  
Marie Gamarra ◽  
Takuma Nemoto ◽  
T.Ming Chu

Blood ◽  
1993 ◽  
Vol 82 (10) ◽  
pp. 3045-3051
Author(s):  
M Schattner ◽  
M Lazzari ◽  
AS Trevani ◽  
E Malchiodi ◽  
AC Kempfer ◽  
...  

The present study shows that the ability of soluble immune complexes (IC), prepared with human IgG and rabbit IgG antibodies against human IgG, to trigger platelet activation was markedly higher for IC prepared with cationized human IgG (catIC) compared with those prepared with untreated human IgG (cIC). CatIC induced platelet aggregation and adenosine triphosphate release in washed platelets (WP), gel-filtered platelets (GFP), or platelet-rich plasma (PRP) at physiologic concentrations of platelets (3 x 10(8)/mL) and at low concentrations of catIC (1 to 30 micrograms/mL). On the contrary, under similar experimental conditions, cIC did not induce aggregation in PRP, WP, or GFP. Low aggregation responses were only observed using high concentrations of both WP (9 x 10(8)/mL) and cIC (500 micrograms/mL). Interestingly, catIC were also able to induce platelet activation under nonaggregating conditions, as evidenced by P-selectin expression. Cationized human IgG alone did not induce platelet aggregation in PRP but triggered either WP or GFP aggregation. However, the concentration needed to induce these responses, was about eightfold higher than those required for catIC. The responses induced either by catIC or cationized human IgG were completely inhibited by treatment with heparin, dextran sulphate, EDTA, prostaglandin E1, or IV3, a monoclonal antibody against the receptor II for the Fc portion of IgG (Fc gamma RII). The data presented in this study suggest that IgG charge constitutes a critical property that conditions the ability of IC to trigger platelet activation.


2015 ◽  
Vol 75 (9) ◽  
pp. 1728-1734 ◽  
Author(s):  
Dag Leonard ◽  
Maija-Leena Eloranta ◽  
Niklas Hagberg ◽  
Olof Berggren ◽  
Karolina Tandre ◽  
...  

ObjectivesPatients with systemic lupus erythematosus (SLE) have an ongoing interferon-α (IFN-α) production by plasmacytoid dendritic cells (pDCs). We investigated whether T cells can promote IFN-α production by pDCs.MethodsHuman pDCs were stimulated with immune complexes (ICs) containing U1 small nuclear ribonucleic proteins particles and SLE-IgG (RNA-IC) in the presence of T cells or T cell supernatants. T cells were activated by anti-CD3/CD28 antibodies or in a mixed leucocyte reaction. IFN-α and other cytokines were determined in culture supernatants or patient sera with immunoassays. The effect of interleukin (IL) 3 and granulocyte-macrophage-colony-stimulating factor (GM-CSF) on pDCs was examined by the use of antibodies, and the expression of CD80/CD86 was determined using flow cytometry.ResultsActivated T cells and supernatants from activated T cells increased IFN-α production by >20-fold. The stimulatory effect of T cell supernatants was reduced after depletion of GM-CSF (81%) or by blocking the GM-CSF receptor (55%–81%). Supernatant from activated T cells, furthermore, increased the frequency of CD80 and CD86 expressing pDCs stimulated with RNA-IC from 6% to 35% (p<0.05) and from 10% to 26% (p<0.01), respectively. Activated SLE T cells enhanced IFN-α production to the same extent as T cells from healthy individuals and a subset of patients with SLE had increased serum levels of GM-CSF.ConclusionsActivated T cells enhance IFN-α production by RNA-IC stimulated pDCs via GM-CSF and induce pDC maturation. Given the increased serum levels of GM-CSF in a subset of patients with SLE, these findings suggest that activated T cells may upregulate type I IFN production in SLE.


1977 ◽  
Vol 25 (4) ◽  
pp. 252-258 ◽  
Author(s):  
G Itoh ◽  
S Miura ◽  
I Suzuki

The mouse mesenteric lymph node cells (in the cell suspension and frozen sections) were incubated in the soluble immune complexes of peroxidase-antiperoxidase immunoglobulin G. After being washed, they were reacted with diaminobenzidine tetrahydrochloride. Light microscopically brown-colored granules were observed on the cell surface of a proportion of small lymphocytes. In frozen sections, a proportion of small lymphocytes were stained dark brown on the cell surface. Characterization and control experiments suggest that the binding of peroxidase-antiperoxidase immunoglobulin G to the cell surface is mediated by Fc receptor. Peroxidase-antiperoxidase immunoglobulin G, therefore, can be used as in indicator of Fc receptor.


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