Distribution of sulfated glycosaminoglycans in the animal kingdom: widespread occurrence of heparin-like compounds in invertebrates

Sulfated glycosaminoglycans were isolated from 23 species of 13 phyla of invertebrates and characterized by their electrophoretic migration in three different buffer systems coupled with enzymatic degradation using bacterial heparinase, heparitinases and chondroitinase AC. Heparan sulfate is a ubiquitous compound present in all species analyzed whereas chondroitin sulfate was present in 20 species and heparin-like compounds in 12 species of the invertebrates. The heparin-like compounds were purified from the echinoderm Mellita quinquisperforata (sand dollar) and the crustacean Ucides cordatus (crab) with anticoagulant activities of 60 and 52 IU/mg, respectively. Degradation of these heparins with heparinase produced significant amounts of the trisulfated disaccharide typical of mammalian heparins. This was confirmed by 13C-NMR spectroscopy of the crab heparin. An updated phylogenetic tree of the distribution of sulfated glycosaminoglycans in the animal kingdom is also presented.

Noninherited maternal antigens do not play a role in rheumatoid arthritis susceptibility in Europe. European Consortium on Rheumatoid Arthritis Families

OBJECTIVE

It has been proposed that noninherited maternal antigens (NIMA) (HLA-DR antigens) might play a role in susceptibility to rheumatoid arthritis (RA), especially in patients who are not genetically predisposed, such as those who are HLA-DR4 and/or shared epitope (SE) negative. The present study was undertaken to test the NIMA hypothesis in a large cohort of European RA patients assembled by the European Consortium on RA Families (ECRAF).

METHODS

HLA-DRB1 oligotyping was performed in families of European RA patients for whom both parents were alive. These families were consecutively recruited by the ECRAF between 1996 and 1998, for association studies. The frequencies of HLA-DR NIMA were compared with those of the noninherited paternal antigens (NIPA) after stratification for HLA-DR*04, *0401 and/or *0404, and SE status. NIMA or NIPA that coincided with inherited HLA-DR antigens were considered redundant and excluded from analysis. Calculations concerning the whole group and restricted to patients lacking parental RA were performed.

RESULTS

One hundred seventy families from France (n = 81), Belgium (n = 23), Spain (n = 24), Italy (n = 19), Portugal (n = 14), and The Netherlands (n = 9) were oligotyped. The group of probands was predominantly female (88%), positive for rheumatoid factor, DR*04, and SE (71%, 58%, and 75%, respectively), and had erosive disease (75%). Parental RA was reported in 21 families. Using the NIPA as control, the frequency of HLA-DRB1*04, *0401 and/or *0404-, or SE-positive NIMA was not found to be increased in patients lacking these susceptibility alleles. The same was true when the 21 probands with parental RA were excluded from analysis. In DRB1*04-positive patients, we found no evidence of a relevant effect of HLA-DR3 or DR6 in the NIMA.

CONCLUSION

Our results do not support the notion that noninherited maternal antigens have a role in susceptibility to RA in the offspring.

Structural features and bleeding activity of commercial low molecular weight heparins: neutralization by ATP and protamine

Differences in the structure of three low molecular weight heparins (LMWHs) have been observed by applying physico-chemical methods as well as enzymatic degradation with bacterial heparinase and heparitinase II. The production of enoxaparin maintains the internal structure of the parent heparin with the exception of the unsaturated nonreducing end. In contrast, the production of dalteparin and nadroparin removes part of their nonsulfated uronic acid residues and, unlike enoxaparin and unfractionated heparin (UFH), these LMWHs also contain regions that remain resistant to the action of heparitinase II. Enoxaparin has a lower molecular weight distribution than dalteparin and nadroparin and is composed of at least four discrete molecular weight populations. A rat-tail model demonstrated that LMWHs applied topically or injected intravenously had a lower bleeding potency when compared with UFH treatment. The bleeding potencies of the different LMWHs were similar. Furthermore, adenosine triphosphate (ATP) completely neutralized bleeding caused by LMWHs and UFH in the animal model when applied topically and significantly reduced bleeding in heparinized surgical patients undergoing cardiopulmonary bypass surgery.

Cloning and characterization of cDNA encoding cardosin A, an RGD-containing plant aspartic proteinase

Cardosin A is an abundant aspartic proteinase from pistils of Cynara cardunculus L. whose milk-clotting activity has been exploited for the manufacture of cheese. Here we report the cloning and characterization of cardosin A cDNA. The deduced amino acid sequence contains the conserved features of plant aspartic proteinases, including the plant-specific insertion (PSI), and revealed the presence of an Arg-Gly-Asp (RGD) motif, which is known to function in cell surface receptor binding by extracellular proteins. Cardosin A mRNA was detected predominantly in young flower buds but not in mature or senescent pistils, suggesting that its expression is likely to be developmentally regulated. Procardosin A, the single chain precursor, was found associated with microsomal membranes of flower buds, whereas the active two-chain enzyme generated upon removal of PSI is soluble. This result implies a role for PSI in promoting the association of plant aspartic proteinase precursors to cell membranes. To get further insights about cardosin A, the functional relevance of the RGD motif was also investigated. A 100-kDa protein that interacts specifically with the RGD sequence was isolated from octyl glucoside pollen extracts by affinity chromatography on cardosin A-Sepharose. This result suggests that the 100-kDa protein is a cardosin A receptor and indicates that the interaction between these two proteins is apparently mediated through RGD recognition. It is possible therefore that cardosin A may have a role in adhesion-mediated proteolytic mechanisms involved in pollen recognition and growth.

Structural features and anticoagulant activities of a novel natural low molecular weight heparin from the shrimp Penaeus brasiliensis

A natural low molecular weight heparin (8.5 kDa), with an anticoagulant activity of 95 IU/mg by the USP assay, was isolated from the shrimp Penaeus brasiliensis. The crustacean heparin was susceptible to both heparinase and heparitinase II from Flavobacterium heparinum forming tri- and di-sulfated disaccharides as the mammalian heparins. (13)C and (1)H NMR spectroscopy revealed that the shrimp heparin was enriched in both glucuronic and non-sulfated iduronic acid residues. The in vitro anticlotting activities in different steps of the coagulation cascade have shown that its anticoagulant action is mainly exerted through the inhibition of factor Xa and heparin cofactor II-mediated inhibition of thrombin. The shrimp heparin has also a potent in vivo antithrombotic activity comparable to the mammalian low molecular weight heparins.

Multicenter case-control study of exposure to environmental tobacco smoke and lung cancer in Europe

BACKGROUND

An association between exposure to environmental tobacco smoke (ETS) and lung cancer risk has been suggested. To evaluate this possible association better, researchers need more precise estimates of risk, the relative contribution of different sources of ETS, and the effect of ETS exposure on different histologic types of lung cancer. To address these issues, we have conducted a case-control study of lung cancer and exposure to ETS in 12 centers from seven European countries.

METHODS

A total of 650 patients with lung cancer and 1542 control subjects up to 74 years of age were interviewed about exposure to ETS. Neither case subjects nor control subjects had smoked more than 400 cigarettes in their lifetime.

RESULTS

ETS exposure during childhood was not associated with an increased risk of lung cancer (odds ratio [OR] for ever exposure = 0.78; 95% confidence interval [CI] = 0.64-0.96). The OR for ever exposure to spousal ETS was 1.16 (95% CI = 0.93-1.44). No clear dose-response relationship could be demonstrated for cumulative spousal ETS exposure. The OR for ever exposure to workplace ETS was 1.17 (95% CI = 0.94-1.45), with possible evidence of increasing risk for increasing duration of exposure. No increase in risk was detected in subjects whose exposure to spousal or workplace ETS ended more than 15 years earlier. Ever exposure to ETS from other sources was not associated with lung cancer risk. Risks from combined exposure to spousal and workplace ETS were higher for squamous cell carcinoma and small-cell carcinoma than for adenocarcinoma, but the differences were not statistically significant.

CONCLUSIONS

Our results indicate no association between childhood exposure to ETS and lung cancer risk. We did find weak evidence of a dose-response relationship between risk of lung cancer and exposure to spousal and workplace ETS. There was no detectable risk after cessation of exposure.

Cytokine analysis of human renal allograft aspiration biopsy cultures supernatants predicts acute rejection

BACKGROUND

A Th1 response is said to be associated with transplant rejection and Th2 with tolerance, although this is not agreed by all. Cytokines evaluation in peripheral blood and urine in kidney transplants produces variable results. We hypothesized that measurement of major cytokines involved in Th1/Th2 paradigm on transplant renal-infiltrating cells could bring valuable scientific and clinical information.

METHODS

Fifty-six adult cadaver kidney transplants were subdivided into 21 stable patients (group A), 22 suffering acute rejection (group B), 10 with chronic rejection (group C) and three with CMV disease (group D). Fine-needle aspiration biopsies were cultured and their supernatants analysed for IL-2, IL-4, IL-10 and IFN-gamma.

RESULTS

Group A produced small amounts of both IL-2 and IL-10 while group B synthetized significantly higher IL-2 and significantly lower IL-10 amounts than group A. Group B produced significantly more IL-2 than A on day 7 post-transplantation, several days before rejection supervened. Group C produced IL-10 and very low amount of IL-2. Group D produced both IL-2 and IL-10. We did not find any IL-4, and IFN-gamma was present in a few samples. For IL-2, sensitivity, specificity, negative and positive predictive values for acute rejection were 100, 87.2, 94.7 and 83.3%, respectively.

CONCLUSIONS

Cytokine analysis in fine-needle aspiration biopsy cultures supernatants is a very useful immunological screening method for kidney transplants. IL-2 synthesis on day 7 post-transplantation reliably predicted the risk of impending acute rejection during the first weeks. The cytokine pattern suggests that acute rejection is associated with Th1, stable patients with Th0/Th2, and chronic rejection with Th2 patterns.

Cultures of aspiration biopsy specimens in the immunological monitoring of renal transplants

OBJECTIVE

Graft-infiltrating cells (GIC) have been studied in heart, lung, and liver transplants and have been shown to have greater proliferative ability when taken from rejecting allografts. Our aim was to study GIC harvested by fine-needle aspiration biopsy (FNAB) in renal transplant recipients.

PATIENTS AND METHODS

93 adult patients entered the study. The FNABs were done on the 7th, 14th, and 30th day after transplantation in stable cases and whenever a rejection crisis supervened.

RESULTS

The proliferation responses of GIC were significantly higher in rejection than in stable cases during the 1st month after transplantation. The sensitivity for rejection was 96.4%, the specificity 91.3%, the negative predictive value 98.7%, and the positive predictive value was 93.3% among dysfunctioning grafts.

CONCLUSIONS

The study of the proliferative capacity of graft-infiltrating cells in renal transplants is a safe and very useful immunologic monitoring tool, and it could improve the FNAB diagnostic accuracy.

T and B lymphocytes, total serum IgE and peripheral eosinophils in bronchial asthma

Absolute T and B lymphocytes, assayed by E and EAC rosette techniques, serum IgE levels, total eosinophil counts and delayed hypersensitivity cutaneous reactions were studied in 39 asthmatic subjects (19 extrinsic asthmas and 20 intrinsic asthmas) and in 15 age-matched control subjects. The mean value of T lymphocytes was 1753 +/- 709 mm.3 in the extrinsic group, 1511 +/- +/- 530 mm.3 in the intrinsic, and 1609 +/- 451 mm.3 in the controls. There was no statistical difference between the two groups of patients and the controls (P > 0.05). There was also no statistical difference of B lymphocytes between the two groups of patients and the controls. Serum IgE was elevated in 8 extrinsic asthmatics (42.1%), in one intrinsic (5%), and in none of the control population. The mean value of eosinophils ws significantly higher (P < 0.01) in the extrinsic group as compared to the controls. The same was true of the intrinsic group, but not so significantly (P congruent to 0.02). No correlation was observed between the number of T lymphocytes and the skin tests, serum IgE and total eosinophil counts.