Qualitative and quantitative alterations of cell surface carbohydrate residues during epidermal morphogenesis

Proliferative Effect of Tilapia Fish (Oreochromis niloticus) Lectin on BALB/c Mice Splenocytes

BACKGROUND

Lectins have been studied in recent years due to their immunomodulatory activities.

OBJECTIVE

We purified a lectin named OniL from tilapia fish (Oreochromis niloticus) and here we analyzed the cell proliferation and cytokine production in Balb/c mice splenocytes.

METHODS

Cells were stimulated in vitro in 24, 48, 72 hours and 6 days with different concentrations of OniL and Con A. Evaluation of cell proliferation was performed through [3H]-thymidine incorporation, cytokines were investigated using ELISA assay and cell viability assay was performed by investigation of damage through signals of apoptosis and necrosis.

RESULTS

OniL did not promote significant cell death, induced high mitogenic activity in relation to control and Con A and stimulated the cells to release high IL-2 and IL-6 cytokines.

CONCLUSION

These findings suggest that, like Con A, OniL lectin can be used as a mitogenic agent in immunostimulatory assays.

Carbohydrate recognition by boronolectins, small molecules, and lectins

Carbohydrates are known to mediate a large number of biological and pathological events. Small and macromolecules capable of carbohydrate recognition have great potentials as research tools, diagnostics, vectors for targeted delivery of therapeutic and imaging agents, and therapeutic agents. However, this potential is far from being realized. One key issue is the difficulty in the development of "binders" capable of specific recognition of carbohydrates of biological relevance. This review discusses systematically the general approaches that are available in developing carbohydrate sensors and "binders/receptors," and their applications. The focus is on discoveries during the last 5 years.

Embryotoxic activity and differential binding of plant-derived carbohydrate-recognizing proteins towards the sea urchin embryo cells

The embryotoxic activity and differential binding of plant-derived carbohydrate-recognizing proteins on sea urchin (Lytechinus variegatus) embryo cells was investigated. IC50 doses for toxicity on larvae development varied from 0.6 up to 96.3 microg ml(-1) and these effects were largely reversed by previously heating the proteins. Changes in the glycoconjungate status of the cell surface were assessed by time-course binding of the proteins during embryogenesis according to their carbohydrate-binding specificity. Glucose/mannose binding-proteins bound embryo cells at the same stage of development, at a similar stage to the N-acetylglucosamine/N-acetylneuraminic acid binding-protein (WGA) and earlier than galactose specific ones. FITC-conjugates of these proteins confirmed the above results and revealed the presence of specific and differential receptors for them. Inhibition assays using inhibitory glycoproteins significantly diminished the labelled patterns of FITC-conjugates. In conclusion, the assayed proteins exhibited embryotoxicity and their binding requirements were useful for following changes in the pattern of cell surface glycoconjugates on embryo cells of sea urchin. This property could be useful in analyzing other cell types.