IL-1 up-regulates osteopontin expression in experimental crescentic glomerulonephritis in the rat

Osteopontin (OPN) is a macrophage chemotactic and adhesion molecule that acts to promote macrophage infiltration in rat anti-glomerular basement membrane (GBM) glomerulonephritis. The present study investigated the role of interleukin-1 (IL-1) in the up-regulation of renal OPN expression in this disease model. Accelerated anti-GBM glomerulonephritis was induced in groups of six rats. Animals were treated by a constant infusion of the IL-1 receptor antagonist or saline (control) over days -1 to 14 (induction phase) or days 7 to 21 (established disease). In normal rat kidney, OPN was expressed in a few tubules (<5%) and absent from glomeruli. During the development of rat anti-GBM disease (days 7 to 21), there was substantial up-regulation of OPN mRNA and protein expression in glomeruli (>5 cells per glomerular cross-section) and tubular epithelial cells (50-75% OPN-positive). Up-regulation of OPN expression was associated with macrophage accumulation within the kidney, severe proteinuria, loss of renal function, and severe histological damage including glomerular crescentic formation and tubulointerstitial fibrosis. In contrast, IL-1 receptor antagonist treatment of either the induction phase of disease or established disease significantly reduced OPN mRNA and protein expression in glomeruli (/75-85%, P < 0.001) and tubules (/45-60%, P < 0.001). The reduction in OPN expression was associated with significant inhibition of macrophage accumulation and progressive renal injury. In vitro, the addition of IL-1 to the normal rat tubular epithelial cell line NRK52E up-regulated OPN mRNA and protein levels, an effect that was dose-dependent and inhibited by the addition of IL-1 receptor antagonist, thus demonstrating that IL-1 can act directly to up-regulate renal OPN expression. In conclusion, this study provides in vivo and in vitro evidence that IL-1 up-regulates OPN expression in experimental kidney disease and support for the argument that inhibition of OPN expression is one mechanism by which IL-1 receptor antagonist treatment suppresses macrophage-mediated renal injury.     

Lectin binding to formalin-fixed paraffin sections.

Lectins are potentially useful tools in histopathology for the identification of carbohydrates and distinguishing cells according to their type, differentiation or function. Conjugated to fluorescent or enzyme labels, lectins are simple to use on fresh tissue but fixation and processing sequesters glycoconjugates and dissolves out fat-linked sugars. We describe here the use of labelled antibodies to lectins to localise sites of lectin binding and increase sensitivity, combined with trypsin and neuraminidase to reveal sequestered carbohydrates. Absorbing lectins with appropriate sugars establishes the specificity of binding and allows lectins to be used as sensitive and specific reagents.     

Regulation of the synthesis of Sindbis virus-specified RNA: role of the virion core protein

Cells infected with seven different RNA+ mutants of Sindbis virus were found to accumulate a virus-specified polypeptide of mol. wt. 144000 (p144) during incubation at the non-permissive temperature, while at the same time synthesis of the virus structural proteins was drastically reduced. Mapping of the tryptic peptides of p144 showed that it contained the amino acid sequences of all the virus structural proteins. At the non-permissive temperature cells infected with the same seven mutants (out of 28 examined) also showed increased synthesis of 26S RNA, the mRNA for the virus structural proteins, relative to 42S RNA, and the virus genome, compared with infections by wild-type virus. We propose that both these phenotypic effects are the results of a single mutational step and that the primary defect in the processing of the virus structural protein precursor induces the relatively increased rate of synthesis of structural protein mRNA. Temperature-shift experiments with mutant-infected cells showed that p144 itself is not the agent of this effect. The failure of exposure to zinc ions to alter the RNA ratio in wild-type virus-infected cells suggested that the virus envelope proteins are not involved either, since their synthesis is preferentially inhibited under these circumstances. It is possible that it is the failure to synthesize the proper quantity of core protein in the mutant-infected cells which causes the shift of RNA synthesis in favour of structural protein mRNA.     

Double-blind, placebo-controlled food challenge (DBPCFC) as an office procedure: a manual

There is now enough experience with the use of double-blind, placebo-controlled, food challenge (DBPCFC) to recommend its use as an office procedure for most patients complaining of adverse reactions to foods. This manual discusses the practical methods required for the allergist to undertake DBPCFC in the office. Thorough histories supplemented by food allergen skin testing are used to design a DBPCFC that carefully attempts to reproduce the history of food-induced symptoms described by the patient. Precautions that must be taken are delineated before challenge, as is treatment that may be required if a reaction occurs. For those foods to which challenges are positive, longitudinal evaluation with repeated challenge at appropriate intervals help to determine whether or not the problem will resolve over a period of time.     

Chronic treatment of female rhesus monkeys with low doses of the antiprogestin ZK 137 316: establishment of a regimen that permits normal menstrual cyclicity

Large doses of antiprogestin typically disrupt menstrual cyclicity. A chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which permits continued menstrual cyclicity but alters gonadal- reproductive tract activity, was established. Rhesus monkeys received vehicle (n = 6) or 0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and gonadotrophin profiles were normal during cycles involving vehicle and 0.01 and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle oestradiol and gonadotrophin surges, and subsequent progesterone production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed ovarian cyclicity, menstruation was disrupted in some animals. Increasing the dose to 0.1 mg/kg antagonized pituitary function and resulted in anovulation and amenorrhoea. A chronic low-dose regimen of the antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity, has potential as a contraceptive in women.      

Familial Similarities of Changes in Cognitive, Behavioral, and Physiological Variables in a Cardiovascular Health Promotion Program

A number of studies have demonstrated that physiological andbehavioral cardiovascular disease (CVD) risk factors aggregatewithin families. This fact, and the potential mediating rolethat the family plays in behavior change, have led to the developmentof family-based CVD risk reduction programs, including the SanDiego Family Health Project. The aggregation of behavioral,physiological, and cognitive changes within families was assessedduring a 1-year intervention. We found evidence of modest butsignificant aggregation of change. There was more aggregationof change in behavioral variables than in physiological or cognitivevariables. More significant correlations were found among 3-dayfood record measures than among 24-hour recall dietary measures,suggesting an influence of assessment method. Aggregation ofchange within families was stronger within generations thanacross generations. These data point to the importance of involvingall age groups in health promotion programs.     

Tissue culture of isolated human glomeruli

Glomerular cells have been grown in a reproducible manner from 5 normal human kidneys. A technique is described which combined mechanical disruption of renal cortex and microdissection, and provides large numbers of pure glomeruli within 30--45 mintues. Histological examination shows this technique produces intact glomeruli without cell disturbance. During tissue culture, glomeruli attach to the flask and the intrinsic cells migrate onto the flask and divide. Variations of culture conditions have shown that glomeruli are robust without fastidious culture requirements. Intact kidney tissue can be left at 4 degrees C for perios up to 24 hours prior to isolated of individual glomeruli without affecting subsequent cellular growth in culture. They grow in most commonly used media although the cells require 20% foetal calf serum for optimum growth. Their pH optimum is between 7.0 and 7.4 with temperature optimum of 37 degrees C. as glomeruli must attach prior to cell growth, minimum movement is critical to promote optimum growth. Under these optimum conditions a regular and predictable growth of cells of two distinct types, has been observed over 14 days; one of these types is probably epithelial.