The distribution of serum albumin in the rat testis, studied by electron microscope immunocytochemistry on ultrathin frozen sections

The distribution of serum albumin is of interest in the rat testis because this protein is the principal carrier for testosterone in the plasma and interstitial fluid of this species. We have localized extravascular serum albumin in the rat testis at the electron microscope level, using gold particle immunocytochemistry on ultrathin frozen sections of tissue fixed lightly by perfusion. The same localization was obtained with three different antisera. Preabsorption and normal rabbit serum controls were negative, and Western blots of testis extracts showed major activity only at the molecular weight of albumin. Serum albumin occurred in substantial concentration throughout extracellular space in the interstitial tissue, as well as in the space between the boundary layer and the base of the seminiferous epithelium. Immunoreactivity extended between Sertoli cells, as well as around spermatogonia and early primary spermatocytes (to stage 11), but did not traverse the Sertoli-Sertoli junctions that comprise the blood-testis barrier. Macrophages in the interstitial tissue showed some endocytic activity. If perfusion fixation was carried out in a manner that flushed most of the albumin from the interstitial space, then a layer of albumin remained on the surface of Leydig cells and many macrophages but was minimal or absent on the surface of other cell types that are normally in contact with albumin, such as Sertoli cells, spermatogonia, myoid cells, lymphatic endothelium, fibroblasts, or cells of blood vessels.     

Significance of Cytoplasmic Microtubules in Lupus Nephritis

Twenty-five renal and three skin biopsies from 14 cases of systemic lupus erythematosus with lupus nephritis were examined by electron microscope. Seventy-five renal biopsies from nonlupus cases consisting of 35 adults and 40 children were used for comparative study. Clusters of cytoplasmic microtubules, which have been referred to as virus-like particles, were observed in the endothelial cells of glomerular and peritubular capillaries in renal biopsies of all lupus cases. The clusters of microtubules were larger and more numerous in the initial biopsies with mild glomerular changes and in the second biopsies from two cases during a period of more severe relapse. Clusters of microtubules were fewer and smaller in renal biopsies with more advanced glomerular changes. Skin biopsies showed similar cytoplasmic inclusions in arterioles and capillaries. Cytoplasmic microtubules were also observed in 3 adults and 13 children of 75 patients who had no systemic lupus erythematosus. Although the formation of the cytoplasmic microtubules may be related to a virus infection, this suggestion cannot be confirmed from the morphologic findings of this study. Of additional interest is the evidence that these microtubules are not cytoplasmic changes secondary to corticosteroid therapy. It is concluded that the presence of many large clusters of cytoplasmic microtubules is specific for lupus nephritis, and it may be substantiated by similar findings in the skin.     

Local delivery of c-myc neutrally charged antisense oligonucleotides with transport catheter inhibits myointimal hyperplasia and positively affects vascular remodeling in the rabbit balloon injury model.

Myointimal hyperplasia after percutaneous transluminal coronary angioplasty (PTCA) is a key component of the process of restenosis. The c-myc is a critical cell-cycle division protein involved in the formation of neointima. We evaluated the long-term impact of local delivery of c-myc neutrally charged antisense oligonucleotides (Resten-NG) on myointimal hyperplasia after PTCA in a rabbit model. PTCA was performed in the iliac arteries of 25 New Zealand white rabbits, using a Transport catheter at 8 atm for 30 sec, three times; 500 microg Resten-NG (n = 11) or saline (n = 14) was delivered to the PTCA site at 2 atm with the outer balloon for 2 min. The diet was supplemented with 0.25% cholesterol for 10 days before and 60 days after PTCA. Angiography was performed at harvest, and vessels were fixed in formalin, processed, and stained with hematoxylin and eosin (H&E) and Movat. Quantitative angiography showed that local delivery of antisense c-myc at PTCA reduced late luminal loss from 1.8 +/- 0.30 mm in control animals to 0.90 +/- 0.30 mm in the treatment group (P = 0.001). Histological analysis by planimetry showed that intimal areas were 1.67 +/- 0.44 mm(2) and 0.82 +/- 0.32 mm(2) in the control and antisense delivery groups, respectively (P < 0.05). We conclude that local delivery of Resten-NG inhibited myointimal hyperplasia after PTCA in cholesterol-fed rabbits for up to 60 days.     

Treatment of infolding related to the gore TAG thoracic endoprosthesis

The present report describes three cases of thoracic aortic endograft infolding or collapse involving the Gore TAG system. The cases include a penetrating aortic injury, a blunt aortic injury, and a symptomatic type B dissection. In the first case, infolding occurred in a delayed fashion after a normal-appearing 3-month follow-up computed tomographic angiogram. In the other two cases, infolding occurred during the immediate postoperative phase. One of the patients underwent explantation and surgical repair. The other two underwent endovascular repair of the infolded endograft by placement of a balloon-expandable stent in one case and a self-expanding stent in the other.     

Enzyme-linked immunosorbent assay using multimers of the 16th non-collagenous domain of the BP180 antigen for sensitive and specific detection of pemphigoid autoantibodies

Bullous pemphigoid (BP) and pemphigoid gestationis (PG) are acquired autoimmune subepidermal blistering diseases characterized by autoantibodies against the hemidesmosomal proteins BP180/type XVII collagen and BP230. In the vast majority of BP and PG patients, these autoantibodies bind to epitopes clustered within the 16th non-collagenous domain of BP180. An ELISA system for the detection of these autoantibodies was developed and evaluated using 16th non-collagenous domain (NC16A) tetramers instead of monomers. In contrast to antigens fused to large proteins used in the past for the detection of autoantibodies against type XVII collagen, tetrameric antigen fragments bearing a small hexahistidine tag allow for high expression levels without the need to cleave off the fusion partner. Using tetrameric BP180 NC16A, positive reactions were found in 106 (89.8%) of 118 randomly selected BP sera and in all of 20 (100%) randomly selected PG sera, whereas only 2.2% of a large cohort of control subjects were positive in this assay, including patients with rheumatoid arthritis (two of 107), progressive systemic sclerosis (two of 50), systemic lupus erythematosus (one of 72), and healthy blood donors (10 of 494). Thus, the sensitivity and specificity of the new anti-tetrameric NC16A ELISA were 89.9% and 97.8% respectively. Levels of circulating autoantibodies against BP180 paralleled disease activity in the pemphigoid patients. In conclusion, the use of tetrameric NC16A in ELISA results in a sensitive and specific tool for diagnosis and monitoring of BP and PG.