Differential binding of conA and WGA on the cell surface,the role of sialic acid in their expression and the increased activity of sialidase after cis-Platin treatment

Summary It is reported that concanavalin A (conA) and wheat germ agglutinin (WGA) have a differential binding pattern on normal mouse spleen lymphocytes and the surface of Dalton's lymphoma cells. It is suggested that sialic acid on the cell surface controls the expression of lectin binding sites. Further, it has been observed that the increased release of sialic acid from cell surfaces aftercis-dichlorodiammine platinum (II) (cis-Platin) treatment is due to the increased activity of sialidase.To whom reprint requests should be addressed.     

Differential binding of conA and WGA on the cell surface, the role of sialic acid in their expression and the increased activity of sialidase after cis-Platin treatment

It is reported that concanavalin A (conA) and wheat germ agglutinin (WGA) have a differential binding pattern on normal mouse spleen lymphocytes and the surface of Dalton's lymphoma cells. It is suggested that sialic acid on the cell surface controls the expression of lectin binding sites. Further, it has been observed that the increased release of sialic acid from cell surfaces after cis-dichlorodiammine platinum (II) (cis-Platin) treatment is due to the increased activity of sialidase.     

The role of sialic acid in 5-HT binding to synaptic membranes.

The high affinity binding of [14C]5-HT to nerve ending membranes isolated from rat brain is not affected by neuraminidase treatment. The specificity of ligand receptor interaction was demonstrated by displacement studies with tryptamine derivatives, noradrenaline, and acetylcholine.     

Plasma lipid-bound sialic acid alterations in neoplastic diseases

Plasma lipid-bound sialic acid (LSA) was assayed in normal volunteers, patients with non-malignant diseases, and a variety of cancer patients. Mean plasma LSA in 50 normal volunteers, 16 patients with non-malignant diseases, 54 breast cancer, 17 lung cancer, 15 colon cancer, 7 ovarian cancer, 5 prostate cancer, 4 leukemia, 4 gastrointestinal, 3 thyroid cancer, 3 pancreas cancer and 2 adrenal cancer patients were 17.7, 23.2, 58, 85, 56.7, 46.2, 56.7, 53.3, 31.1, 33.2 and 119.5 mg/dl, respectively. None of the normal volunteers had elevated plasma LSA values. Plasma LSA level was not significantly different in male and female volunteers. Two out of 114 different cancer patients had plasma LSA levels within normal range exhibiting 98.2% sensitivity of the assay. Plasma LSA, which is relatively simple to assay, may be used as a tumor marker in wide variety of neoplastic diseases.     

Plasma lipid-bound sialic acid alterations in neoplastic diseases

Summary Plasma lipid-bound sialic acid (LSA) was assayed in normal volunteers, patients with non-malignant diseases, and a variety of cancer patients. Mean plasma LSA in 50 normal volunteers, 16 patients with non-malignant diseases, 54 breast cancer, 17 lung cancer, 15 colon cancer, 7 ovarian cancer, 5 prostate cancer, 4 leukemia, 4 gastrointestinal, 3 thyroid cancer, 3 pancreas cancer and 2 adrenal cancer patients were 17.7, 23.2, 58, 85, 56.7, 46.2, 56.7, 53.3, 31.1, 33.2 and 119.5 mg/dl, respectively. None of the normal volunteers had elevated plasma LSA values. Plasma LSA level was not significantly different in male and female volunteers. Two patients with rheumatic arthritis had LSA values slightly elevated over the mean + 2 SD for the normal volunteers. Two out of 114 different cancer patients had plasma LSA levels within normal range exhibiting 98.2% sensitivity of the assay. Plasma LSA, which is relatively simple to assay, may be used as a tumor marker in wide variety of neoplastic diseases.     

Changes in the sialic acid content of chick thymus and bursa of Fabricius during age-involution.

The sialic acid content of both thymus and bursa of Fabricius during their growth and involution phases in chick has been reported in this study. It is observed that the sialic acid concentration is very high in 1-week-old chickens. The concentration subsequently decreases to a significant level and rises again prior to the onset of involution. In the post-involution period, a more or less minimal and constant level is maintained. The role of sialic acid in cellular activities of thymo-bursal system has been discussed.     

Phosphatases IX. Differences in sialic acid content of rat liver alkaline phosphatase isoenzymes

Zusammenfassung Die Heterogeneität der alkalischen Phosphatase in der Rattenleber wird beschrieben. Anodische und kathodische Isoenzyme unterscheiden sich unter anderem durch ihre Reaktion auf die Neuraminidase Behandlung.

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V. Volek, J. tpán, E. Beneová andF. Hemanský, Sb. lék. in print (1973).     

The role of sialic acid in determining the survival of circulating interferon

Summary Rabbit interferon has been extensively desialylated and its metabolic behaviour has been evaluated in the rabbit. The half-life of asialointerferon is significantly shorter than the native interferon and its urinary excretion becomes negligible. Moreover the rapid uptake of asialointerferon by the isolated and perfused rabbit liver, suggests a hitherto unsuspected catabolic pathway for this glycoprotein.This work was supported by a grant from the Consiglio Nazionale delle Ricerche, Roma (subproject on antiviral therapy), contract No. 76.00646.84).     

Pituitary sialic acid concentration during the estrous cycle of rats

Zusammenfassung Bei der Ratte wurde der Sialinsäuregehalt des Hypophysenvorderlappens während des Prooestrus, Oestrus und Dioestrus bestimmt. Da das Luteinhormon der Ratten keine Sialinsäure enthält, können die Schwankungen des Sialinsäuregehaltes als Mass für die FSH-Konzentrationen genommen werden.

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The authors are grateful to Prof.M.R.N. Prasad and Prof.C.M.S. Dass for providing all facilities and encouragements.     

Role of salivary glands in the maintenance of midgut amylase activity inPeriplaneta americana L.

Summary It was experimentally demonstrated, by the surgical removal of salivary glands and severence of salivary ducts, that most of the amylase in the gut ofPeriplaneta americana comes from the salivary glands.We wish to acknowledge Prof. H. Swarup (Jiwaji University, Gwalior, M.P.) for working facilities provided at School of Studies in Zoology, Vikram University, Ujjain, M.P., and Council of Scientific and Industrial Research, New Delhi, for fincancial support in the form of Junior Research Fellowship to one of us (O.P.A.)     

The role of sialic acid in determining the life-span of circulating cells and glycoproteins

Summary The role of sialic acid in determining the life of circulating cells and glycoproteins is reviewed and an attempt is made to assess its real importance and to interpret the desialylation pathway. An overall view of factors, including desialylated glycoprotein fragments, that may regulate hepatic synthesis of glycoproteins is presented.Acknowledgments. The author wishes to thank Drs.A. Viti andG. P. Pessina for helpful discussion and comments.     

Masking action of basic proteins on sialic acid carboxyls in epithelial mucins

Riassunto In questo lavoro si è cercato di dimostrare, con mezzi istochimici, che l'acido sialico presente in tessuti di ghiandole mucose e sierose si trova in due forme differenti. Per la maggioranza tale acido è libero ed il suo gruppo carbossilico interagisce con alcuni coloranti cationici. Una piccola quantità di acido neuramminico è, invece, bloccata da proteine basiche e può essere istochimicamente rivelata solo dopo trattamento con enzimi proteolitici.

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This work was supported by research grants (D-1325 and D-1326) from the National Institutes of Health, United States Public Health Service.

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On leave of absence from the University of Rome Medical School, Viale Regina Elena 287-A, Roma (Italia).     

The role of sialic acid in 5-HT binding to synaptic membranes

Summary The high affinity binding of [¹⁴C]5-HT to nerve ending membranes isolated from rat brain is not affected by neuraminidase treatment. The specificity of ligand receptor interaction was demonstrated by displacement studies with tryptamine derivatives, noradrenaline, and acetylcholine.The expert technical assistance of Miss Christiane von Winterfeld is appreciated. This work was supported by a grant of the Deutsche Forschungsgemeinschaft.     

Changes in the sialic acid content of chick thymus and bursa of Fabricius during age-involution

Summary The sialic acid content of both thymus and bursa of Fabricius during their growth and involution phases in chick has been reported in this study. It is observed that the sialic acid concentration is very high in 1-week-old chickens. The concentration subsequently decreases to a significant level and rises again prior to the onset of involution. In the postinvolution period, a more or less minimal and constant level is maintained. The role of sialic acid in cellular activities of thymo-bursal system has been discussed.Supported by the University Grants Commission, Govt of India under the scheme Support to Research.