Expression and localization of heat shock proteins in rat basophilic leukemia cells: differential modulation by degranulation, thermal or oxidative stress.

Abstract

BACKGROUND:

Rat basophilic leukemia (RBL-2H3) cells are well characterized in terms of morphological and biochemical changes upon activation, and have been extensively used as a model system for studying the mechanisms of the immediate hypersensitivity reaction. To investigate whether overexpression of heat shock/stress proteins (HSP) is involved in the mast cell-dependent reactivity, we examined the adaptive responses of RBL-2H3 cells to classical stress conditions such as heat shock or oxidative injury produced by an aqueous extract of tobacco smoke.

METHODS:

HSP were determined by flow cytometry and immunocytochemistry. Degranulation was confirmed as the release of beta-hexosaminidase, determined spectrophotometrically, and by electron microscopy experiments.

RESULTS:

We found that RBL-2H3 cells respond to heat shock or oxidative injury by the synthesis of both the inducible 72 kDa HSP (Hsp70), and the oxidation-specific 32 kDa heme oxygenase (HO)-1. Heat shock induced mainly Hsp70 in a cell growth-dependent manner, whereas oxidative stress induced mainly HO-1 in a cell growth-independent manner. However, heat shock or oxidative stress had no significant effects on degranulation.

CONCLUSION:

Stress-mediated synthesis of HSP was not associated with RBL-2H3 degranulation and likewise, degranulation did not induce HSP.

• Authors: M Bachelet, F Marchand, E Souil, D François, E Mariéthoz, A Weyer, B S Polla
• Journal: Allergy (Allergy) Vol. 57 Issue 9 Pg. 791-7 (Sep 2002) ISSN: 0105-4538 [Print] Denmark
• PMID: 12169174 (Publication Type: Journal Article)

Chemical References

• HSP70 Heat-Shock Proteins
• Ionophores
• Calcimycin
• Heme Oxygenase (Decyclizing)
• Heme Oxygenase-1
• beta-N-Acetylhexosaminidases

Topics

• Animals
• Calcimycin (pharmacology)
• Cell Degranulation
• Cell Division
• Flow Cytometry
• HSP70 Heat-Shock Proteins (biosynthesis)
• Heme Oxygenase (Decyclizing) (biosynthesis)
• Heme Oxygenase-1
• Hot Temperature
• Hypersensitivity (metabolism)
• Immunohistochemistry
• Ionophores (pharmacology)
• Leukemia, Basophilic, Acute (metabolism)
• Oxidative Stress
• Rats
• Tobacco
• Tumor Cells, Cultured
• beta-N-Acetylhexosaminidases (metabolism)