Unterwegs im Universum der Deutungen: Dorothea Langes Fotozyklus "Migrant Mother"

Der Beitrag verfolgt die Karriere eines Bildes der amerikanischen Fotografin Dorothea Lange, das im März 1936 als Presseaufnahme in Umlauf kam und in der Folge unter dem Titel "Migrant Mother" zu einer Ikone der Großen Depression in den USA wurde. Das Foto wird hier erstmals im Zusammenhang der gesamten Serie von sieben Aufnahmen analysiert, der es entnommen ist. Ausgehend vom politisch-sozialen Kontext des New Deal leistet der Autor eine ikonographische Analyse; er arbeitet die semantischen Überschreibungen und Adaptionen des Bildes im Verlauf seiner Rezeptionsgeschichte heraus und ordnet das Foto schließlich vier verschiedenen Diskursen zu, die die Semantik der "Migrant Mother" maßgeblich bestimmt haben. Die historische Bedeutung von Dokumentarfotografie erweist sich dabei im Wesentlichen als eine Funktion der sozialen und diskursiven Praxis ihrer Verwendung.This article analyses Dorothea Lange's famous photograph 'Migrant Mother', which was first published in March 1936, in relation to its social and iconographic contexts. The photograph has become not only a pictorial symbol of America’s Great Depression but also an 'all inclusive icon' representing different narratives. This is the first time in which this picture has been interpreted on the basis of its original sequence of seven exposures. The author begins by looking at the political and social contexts of New Deal propaganda as a framework for an iconographic interpretation of the picture. He then shows that four different discourses have been used to construct the ‘meaning’ of this image over time. In light of this argument, the historical meaning of documentary photography proves to be a function of its social/political utility and of the discourses in which it is embedded

ATZ11 Recognizes Not Only Z-α₁-Antitrypsin-Polymers and Complexed Forms of Non-Z-α₁-Antitrypsin but Also the von Willebrand Factor

<div><p>Aims</p><p>The ATZ11 antibody has been well established for the identification of α₁-anti-trypsin (AAT) molecule type PiZ (Z-AAT) in blood samples and liver tissue. In this study, we systematically analyzed the antibody for additional binding sites in human tissue.</p><p>Methods and Results</p><p>Ultrastructural ATZ11 binding was investigated immunoelectron microscopically in human umbilical vein endothelial cells (HUVECs) and in platelets of a healthy individual. Human embryonic kidney (HEK293) cells were transiently transfected with Von Willebrand factor (VWF) and analyzed immunocytochemically using confocal microscopy and SDS-PAGE electrophoresis followed by western blotting (WB). Platelets and serum samples of VWF-competent and VWF-deficient patients were investigated using native PAGE and SDS-PAGE electrophoresis followed by WB. The specificity of the ATZ11 reaction was tested immunohistochemically by extensive antibody-mediated blocking of AAT- and VWF-antigens.</p><p>ATZ11-positive epitopes could be detected in Weibel-Palade bodies (WPBs) of HUVECs and α-granules of platelets. ATZ11 stains pseudo-WBP containing recombinant wild-type VWF (rVWF-WT) in HEK293 cells. In SDS-PAGE electrophoresis followed by WB, anti-VWF and ATZ11 both identified rVWF-WT. However, neither rVWF-WT-multimers, human VWF-multimers, nor serum proteins of VWF-deficient patients were detected using ATZ11 by WB, whereas anti-VWF antibody (anti-VWF) detected rVWF-WT-multimers as well as human VWF-multimers. In human tissue specimens, AAT-antigen blockade using anti-AAT antibody abolished ATZ11 staining of Z-AAT in a heterozygous AAT-deficient patient, whereas VWF-antigen blockade using anti-VWF abolished ATZ11 staining of endothelial cells and megakaryocytes.</p><p>Conclusions</p><p>ATZ11 reacts with cellular bound and denatured rVWF-WT and human VWF as shown using immunocytochemistry and subsequent confocal imaging, immunoelectron microscopy, SDS-PAGE and WB, and immunohistology. These immunoreactions are independent of the binding of Z-AAT-molecules and non-Z-AAT complexes.</p></div

Confocal imaging of VWF-transfected HEK293 cells: Pseudo-Weibel-Palade-Body (pseudo-WPB) granules formed after transfection of HEK293 cells using recombinant wild-type VWF (rVWF-WT) constructs: (A, B) Pseudo-WPB granules are shown in green (anti-VWF staining).

<p>(C) The same intracellular structures are stained with ATZ11 (red). (D) Small dot-like signals of less than .25 µm were found in very few HEK293 cells stained with anti-AAT (arrow). (E) Merged images of anti-VWF and ATZ11 stains highlight the co-localization of the antibody-binding sites. At a single cell level, small dot-like positive signals were found in the ATZ11 reaction, which were not co-localized with VWF staining (arrow). (F) Merged images of anti-VWF staining and anti-AAT signals demonstrated that the dot-like anti-AAT positive signals were not associated with pseudo-WPBs (arrow). Scale bar = 10 µm.</p

Comparative immunostaining of temporary artery specimens.

<p>(A) Localization of AAT in the temporal artery. Specimen stained with polyclonal anti-AAT (1∶5000) showed immunoreactivity on the endothelial surface and a gradient of presumably soluble AAT within the vessel wall. (B) ATZ11 (1∶100) showed a distinct staining of the endothelial layer. (C) The endothelial layer is distinctly stained using anti-VFW (1∶500). (D) After saturation with anti-AAT antibody (1∶10), ATZ11 labeled a thin endothelial layer. (E) Blockade with anti-VWF antibody (1∶10) abolished ATZ11 staining (1∶100) of the endothelial layer. (F) Sequential blockade with anti-AAT (1∶10) and anti-VWF (1∶10) completely abolished ATZ11 staining (1∶100).</p

Recombinant von Willebrand Factor Expression in four Transfection Experiments in HEK293 cell lines.

<p>rVFW – recombinant von Willebrand factor.</p

Protein-electrophoretic studies on VWF-transfected HEK293 cells and human serum samples:

<p>(A) <b>SDS-PAGE electrophoresis and subsequent western blotting (WB) and visualization using anti-VWF: (lane 1) cell lysates of recombinant wild-type VWF (rVWF-WT)-transfected HEK293 cells, (lane 2) mock-transfected HEK293 cells.</b> (B) SDS-PAGE electrophoresis and subsequent WB and visualization using ATZ11: (lane 1) of cell lysates of rVWF-WT-transfected HEK293 cells and (lane 2) mock-transfected HEK293 cells. A congruent single band of 225 kDa was detected in the VWF-transfected HEK293 cells using both anti-VWF (A) and ATZ11 (B). (C) SDS-PAGE electrophoresis and subsequent WB of human serum samples of a non-Z healthy individual (lanes 1–2) and of VWF-deficient patients (lanes 3–5) stained with anti-VWF. (D) SDS-PAGE electrophoresis and subsequent WB of serum samples of a non-Z healthy individual (lanes 1–2) and of VWF-deficient patients (lanes 3–5) stained with ATZ11. (E) Native PAGE electrophoresis and subsequent WB of a recombinant VWF (lanes 1–2) and serum samples of a non-Z healthy individual (lanes 3–5) stained with the anti-VWF antibody.</p