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G De Ritis

Publications and source records attributed to G De Ritis.

At least 37 records · Page 2Linked to original sources
PubMed1984

Agglutinating activity of gliadin-derived peptides from bread wheat: implications for coeliac disease pathogenesis.

The PT-digest of bread wheat gliadin was very active in agglutinating undifferentiated human K562(S) cells. This activity was quantitatively, but not qualitatively, similar to that of Con A or WGA. Moreover, Con A-induced cell agglutination was inhibited by mannan and mannose, WGA-induced agglutination by NAG only, and cell agglutination induced by bread wheat gliadin peptides was inhibited by each of these three saccharides. Not only was mannan the most active saccharide in preventing cell agglutination induced by bread wheat gliadin peptides, but it was also able to dissociate agglutinated cells. As compared to the PT- digest of whole bread wheat gliadin, the digest obtained from purified A-gliadin was tenfold more active. The PT-digest of durum wheat gliadin did not show any agglutinating activity.

Agglutination Tests↗
PubMed1984

An in vitro animal model for the study of cereal components toxic in celiac disease.

Peptic-tryptic-Cotazym (PTC) digests were obtained, simulating in vivo protein digestion, from rice, maize, rye, oats, barley, and sorghum prolamines and tested on small intestine cultures from rat fetus. The PTC digests of the prolamine fractions from rice and maize, even when tested at a concentration as high as 0.5 mg/ml, did not affect in vitro differentiation and maturation of fetal rat jejunum that took place in vitro in a way comparable to what happens in vivo. On the contrary, the PTC digests of prolamines from rye, oats, barley, and sorghum were very active in slowing down in vitro development of fetal rat intestine. These results further strengthen earlier findings and all together show that there is a strong correlation between toxicity results of cereal and/or cereal components assessed with clinical trials or in vitro systems based on bioptic specimens of intestinal mucosa from celiac patients and with the culture of rat fetal intestine. Therefore, the rat fetal intestine culture is considered to be an adequate model for screening and investigating cereal peptides which are toxic for the celiac small intestinal mucosa.

Animals↗
PubMed1982

Effects of gliadin-derived peptides from bread and durum wheats on small intestine cultures from rat fetus and coeliac children.

Peptic-tryptic-cotazym (PTC) digests were obtained, simulating in vivo protein digestion, from albumin, globulin, gliadin and glutenin preparations from hexaploid (bread) wheat as well as from diploid (monococcum) and tetraploid (durum) wheat gliadins. The digest from bread wheat gliadins reversibly inhibited in vitro development and morphogenesis of small intestine from 17-day-old rat fetuses, whereas all the other digests (obtained both from nongliadin fractions and from gliadins from other wheat species) were inactive. The PTC-digest from bread wheat gliadins was also able to prevent recovery of and to damage the in vitro cultured small intestinal mucosa from patients with active coeliac disease (gluten-induced entheropathy). The PTC-digest from durum wheat gliadins caused a much less adverse effect on this human pathologic tissue culture system.

Animals↗
PubMed1979

Toxicity of wheat flour proteins and protein-derived peptides for in vitro developing intestine from rat fetus.

A peptic-tryptic-cotazym (PTC) digest of a crude wheat gliadin preparation was obtained under experimental conditions simulating in vivo protein digestion and then fractionated into 10 peaks by ion-exchange chromatography. PTC-gliadin digest and one of its subfractions (coded as fraction 9 according to its elution pattern) were very active in inhibiting in vitro development and morphogenesis of small intestine from 17- and 18-day-old rat fetuses, whereas they were harmless for the culture of jejunum from 21-day-old fetuses. PTC-digest also induced extensive tissue degeneration and necrosis of in vitro cultured small intestinal mucosa from patients with active celiac disease (gluten-induced entheropathy), but did not cause any detectable effect on histologically normal human small intestinal mucosa. Some wheat albumin and gliadin fractions were also tested on in vitro developing small intestine from 17-day-old rat fetus. Among all the tested protein fractions, only one gliadin fraction (coded as alpha 10-gliadin from its gel electrophoretic mobility) exhibited a toxic effect; morphologic alterations induced by alpha 10-gliadin were similar to those induced by PTC-digest and fraction 9.

Albumins↗