The role of the TLR-dependent signaling pathway in the mechanism of phagocyte protection by exogenous heat shock protein HSP70 from the endotoxin action

Preventive Administration of the Heat Shock Protein Hsp70 Relieves Endotoxemia-Induced Febrile Reaction in Pigeons ( ) and Rats

The stress-inducible 70 kDa heat shock protein (Hsp70) can exert a protective effect on endotoxemia and sepsis due to its ability to interact with immune cells and modulate the immune response. However, it remains unknown whether Hsp70 is able to relieve endotoxemia-induced fever. We carried out a comparative study of the effects of preventive administration of the human recombinant Hsp70 (HSPA1A) on lipopolysaccharide (LPS)-induced endotoxemia in pigeons and rats with preimplanted electrodes and thermistors for recording the thermoregulation parameters (brain temperature, peripheral vasomotor reaction, muscular contractile activity). Additionally, we analyzed the dynamics of the white blood cell (WBC) count in rats under the same conditions. It was found that preventive administration of Hsp70 relieves the LPS-induced febrile reaction in pigeons and rats and accelerates the restoration of the WBC count in rats. The data obtained suggest that these warm-blooded animals share a common physiological mechanism that underlies the protective effect of Hsp70.

Exogenous heat shock protein HSP70 reduces response of human neuroblastoma cells to lipopolysaccharide

The effect of exogenous heat shock protein HSP70 and lipopolysaccharide (LPS) on the production of reactive oxygen species (ROS), TNFα secretion, and mRNA expression by human neuroblastoma SK-N-SH cells. It was shown that exogenous HSP70 protects neuroblastoma cells from the action of LPS. The protection mechanism of HSP70 includes a reduction in the production of ROS and TNFα and a decrease in the expression of TLR4 and IL-1β mRNA in SK-N-SH cells induced by LPS.

Influence of encapsulated heat shock protein HSP70 on the basic functional properties of blood phagocytes

Microencapsulated heat shock proteins HSP 70 were studied in terms of their effects on neutrophil apoptosis, production of reactive oxygen species, and secretion of TNF-α by human neurtrophils and monocytes. Encapsulated HSP70 inhibited neutrophil apoptosis by 65% as compared to the effect of nonencapsulated HSP70; TNF-α production by the promonocytic THP-1 cells was similarly inhibited by the non-encapsulated and encapsulated HSP70. Thus, the polyelectrolyte micromolecules can be used as containers for effective delivery of HSP70 up to neutrophils and monocytes to correct the innate immunity functions.