Liposome-templated gold nanoparticles for precisely temperature-controlled photothermal therapy based on heat shock protein expression.

Mild temperature photothermal therapy is gaining more and more attention due to high safety, high specificity and moderate efficacy. However, the therapeutical outcome of mild photothermal therapy is limited due to the overexpression of heat shock proteins (HSPs). Therefore, the precise management of HSP expression is the key to improvement of mild temperature photothermal therapy. However, the correlation between HSP expression and photothermal temperature in vivo is still unclear. To precisely control the photothermal temperature by managing the HSP expression, we quantified the HSP expression at different photothermal temperatures after irradiation on liposome-templated gold nanoparticles, which have high photostability, high photothermal conversion efficiency and low temperature fluctuation (smaller than 1 â„ƒ). We found that the expression of HSP70 was least at 47 â„ƒ, which was the optimal temperature for HSP management. We chose to co-administrate HSP70 inhibitor during 47 â„ƒ photothermal therapy, leading to greatly enhanced tumor inhibition. Our precise temperature-controlled photothermal therapy based on HSP expression offers a new strategy for clinical tumor photothermal therapy.

AMD3100 Augments the Efficacy of Mesothelin-Targeted, Immune-Activating VIC-008 in Mesothelioma by Modulating Intratumoral Immunosuppression.

AMD3100 (plerixafor), a CXCR4 antagonist, has been demonstrated to suppress tumor growth and modulate intratumoral T-cell trafficking. However, the effect of AMD3100 on immunomodulation remains elusive. Here, we explored immunomodulation and antitumor efficacy of AMD3100 in combination with a previously developed mesothelin-targeted, immune-activating fusion protein, VIC-008, in two syngeneic, orthotopic models of malignant mesothelioma in immunocompetent mice. We showed that combination therapy significantly suppressed tumor growth and prolonged animal survival in two mouse models. Tumor control and survival benefit were associated with enhanced antitumor immunity. VIC-008 augmented mesothelin-specific CD8+ T-cell responses in the spleen and lymph nodes and facilitated intratumoral lymphocytic infiltration. However, VIC-008 treatment was associated with increased programmed cell death protein-1 (PD-1) expression on intratumoral CD8+ T cells, likely due to high CXCL12 in the tumor microenvironment. AMD3100 alone and in combination with VIC-008 modulated immunosuppression in tumors and the immune system through suppression of PD-1 expression on CD8+ T cells and conversion of regulatory T cells (Tregs) into CD4+CD25-Foxp3+IL2+CD40L+ helper-like cells. In mechanistic studies, we demonstrated that AMD3100-driven Treg reprogramming required T cell receptor (TCR) activation and was associated with loss of PTEN due to oxidative inactivation. The combination of VIC-008 augmentation of tumor-specific CD8+ T-cell responses with AMD3100 abrogation of immunosuppression conferred significant benefits for tumor control and animal survival. These data provide new mechanistic insight into AMD3100-mediated immunomodulation and highlight the enhanced antitumor effect of AMD3100 in combination with a tumor antigen-targeted therapy in mouse malignant mesothelioma, which could be clinically relevant to patients with this difficult-to-treat disease. Cancer Immunol Res; 6(5); 539-51. ©2018 AACR.

A novel nanoparticle containing neuritin peptide with grp170 induces a CTL response to inhibit tumor growth.

Malignant glioma is among the most challenging of all cancers to treat successfully. Despite recent advances in surgery, radiotherapy and chemotherapy, current treatment regimens have only a marginal impact on patient survival. In this study, we constructed a novel nanoparticle containing neuritin peptide with grp170. The nanoparticle could elicit a neuritin-specific cytotoxic T lymphocyte response to lyse glioma cells in vitro. In addition, the nanoparticle could inhibit tumor growth and improve the lifespan of tumor-bearing mice in vivo. Taken together, the results demonstrated that the nanoparticle can inhibit tumor growth and represents a promising therapy for glioma.

Inhibition of HIV-1 by a Lentiviral Vector with a Novel Tat-Inducible Expression System and a Specific Tropism to the Target Cells.

Today, lentiviral vectors are favorable vectors for RNA interference delivery in anti-HIV therapeutic approaches. Nevertheless, problems such as the specific recognition of target cells and uncontrolled expression of the transgene can restrict their use in vivo. Herein we present a new HIV-inducible promoter to express anti-HIV short hairpin RNA (shRNA) by RNA Pol II in mammalian cells. We likewise showed a novel third-generation lentiviral vector system with more safety and a specific tropism to the target cells. The new promoter, CkRhsp, was constructed from the chicken ß-actin core promoter with the R region of HIV-1 long terminal repeat fused upstream of minimal hsp70 promoter. This system was induced by HIV-1 Tat, and activates transcription of two shRNAs against two conserved regions of HIV-1 transcripts produced in two steps of the virus life cycle. We also mimicked HIV-1 cell tropism by using the HIV-1 envelope in structure of third-generation lentiviral vector. The new fusion promoter efficiently expressed shRNA in a Tat-inducible manner. HIV-1 replication was inhibited in transient transfection and stable transduction assays. The new viral vector infected only CD4+cells. CkRhsp promoter may be safer than other inducible promoters for shRNA-mediated gene therapies against HIV. The use of the wild envelope in the vector packaging system may provide the specific targeting T lymphocytes and hematopoietic stem cells for anti-HIV-1 therapeutic approaches in vivo.

TAT-HSP70 Attenuates Experimental Lung Injury.

Sepsis, a poorly understood syndrome of disordered inflammation, is the leading cause of death in critically ill patients. Lung injury, in the form of acute respiratory distress syndrome (ARDS), is the most common form of organ injury in sepsis. The heat shock response, during which heat shock proteins (HSPs) are expressed, is an endogenous mechanism to protect cells from injury. We have found that the abundance of pulmonary HSP70 is not increased after cecal ligation and double puncture (CLP) in a rat model of sepsis-induced ARDS. Using the HIV-1 trans-activator of transcription (TAT) cell-penetrating protein, we enhanced HSP70 protein abundance in the lung. We found that intratracheal administration of HSP70 using the TAT methodology, just after CLP (CLP-TAT-HSP70), when compared with treatment with phosphate buffered saline (CLP-phosphate buffered saline), significantly increased HSP70 abundance in the lung 24 and 48 h after surgery. Treatment of septic rats with TAT-HSP70 increased HSP70 abundance in histologically normal and abnormal lung regions. In addition, TAT-HSP70 treatment significantly decreased the levels of macrophage inflammatory protein 2 and cytokine-induced neutrophil chemoattractant 1 24 h after CLP. The TAT-HSP70 treatment reduced myeloperoxidase abundance 48 h after CLP and attenuated histological evidence of inflammation at both 24 and 48 h. Administration of TAT-HSP70 also improved 48-h survival in this rat model of sepsis. Thus, intratracheal administration of TAT-HSP70 increased HSP70 abundance in the lung and attenuated the lung injury. Enhancing pulmonary HSP70 using TAT is a novel potential therapeutic strategy for the treatment of ARDS that will be explored further.

Oxidative stress protection by exogenous delivery of rhHsp70 chaperone to the retinal pigment epithelium (RPE), a possible therapeutic strategy against RPE degeneration.

PURPOSE: To measure the cytoprotective effects of rhHsp70 against oxidative stress and study its cellular uptake, intracellular and intraocular distribution in the retinal pigment epithelium. METHODS: Human retinal pigment epithelial cells (ARPE-19) were pre-treated with rhHsp70 for 24 h, 48 h, and 72 h before being exposed to 1.25 mM hydrogen peroxide. Non-treated cells served as control. We analysed interleukin 6 secretion, cell viability, and cytolysis. Uptake and intracellular distribution of fluorescently labelled rhHsp70 were investigated with flow cytometry and confocal microscopy, respectively. Ocular distribution of radioactively labelled rhHsp70 was followed ex vivo in porcine eyes by micro SPECT/CT. RESULTS: After exposure to hydrogen peroxide, IL-6 secretion decreased by 35-39% when ARPE-19 cells were pre-treated with rhHsp70. Cell viability increased by 17-32%, and cell lysis, measured by the release of lactate dehydrogenase, decreased by 6-43%. ARPE-19 cells endocytosed rhHsp70 added to the culture medium and the protein was localized in late endosomes and lysosomes. Following intravitreal injection into isolated porcine eyes, we found 20% rhHsp70 in the RPE. CONCLUSIONS: Recombinant hHsp70 protein offers protection against oxidative stress. RPE cells take up the exogenously delivered rhHsp70 and localize it in late endosomes and lysosomes. This work provides the basis for a therapeutic strategy to target aggregate-associated neurodegeneration in AMD.

[Immunoregulatory properties of Hsp70]. / Immunoregulacyjne wlasciwosci bialek Hsp70.

Heat shock proteins 70 (Hsp70) play an important role in maintaining cellular homeostasis. As molecular chaperones, Hsp70 are responsible for proper folding of newly synthesized polypeptides and refolding of misfolded and aggregated proteins. Hsp70 are involved in cellular transport and participate in signal transduction processes. The presence of Hsp70 in the extracellular space is associated with development of various pathological conditions, including autoimmune and cancer diseases. Recent data suggest anti-inflammatory property of Hsp70 confirmed in both in vitro and animal models. This paper summarizes recent data regarding immunoregulatory properties of Hsp70, and presents promising results of the studies concerning the application of heat shock proteins in treatment of chronic inflammatory diseases.

TAT-Hsp70 induces neuroprotection against stroke via anti-inflammatory actions providing appropriate cellular microenvironment for transplantation of neural precursor cells.

Heat-shock protein 70 (Hsp70) protects against cerebral ischemia, which is attributed to its chaperone activity. However, recent reports also describe pro-inflammatory actions of Hsp70 via activation of Toll-like receptors (TLR). Using membrane-permeable transactivator of transcription (TAT)-Hsp70, we analyzed TAT-Hsp70-induced neuroprotection and its underlying mechanism after cerebral ischemia in mice. Infusion of TAT-Hsp70 reduced infarct volume and enhanced blood-brain barrier integrity on day 3 poststroke, when given no later than 12 hours. The latter was associated with reduction of microglial activation, although upregulation of pro-inflammatory TLR-2/4 was observed both in verum and in control animals. Nevertheless, protein abundance and nuclear translocation of downstream nuclear factor kappa B (NF-κB) as well as proteasomal degradation of the NF-κB regulator Ikappa B alpha (IκB-α) were significantly reduced by TAT-Hsp70. TAT-Hsp70-induced neuroprotection and functional recovery were restricted to 4 weeks only. However, TAT-Hsp70 provided an appropriate extracellular milieu for delayed intravenous transplantation of adult neural precursor cells (NPCs). Thus, NPCs that were grafted 28 days poststroke induced long-term neuroprotection for at least 3 months, which was not due to integration of grafted cells but rather due to paracrine effects of transplanted NPCs. Conclusively, TAT-Hsp70 ameliorates postischemic inflammation via proteasome inhibition, thus providing an appropriate extracellular milieu for delayed NPC transplantation and culminating in long-term neuroprotection.

Mutant HSP70 reverses autoimmune depigmentation in vitiligo.

Vitiligo is an autoimmune disease characterized by destruction of melanocytes, leaving 0.5% of the population with progressive depigmentation. Current treatments offer limited efficacy. We report that modified inducible heat shock protein 70 (HSP70i) prevents T cell-mediated depigmentation. HSP70i is the molecular link between stress and the resultant immune response. We previously showed that HSP70i induces an inflammatory dendritic cell (DC) phenotype and is necessary for depigmentation in vitiligo mouse models. Here, we observed a similar DC inflammatory phenotype in vitiligo patients. In a mouse model of depigmentation, DNA vaccination with a melanocyte antigen and the carboxyl terminus of HSP70i was sufficient to drive autoimmunity. Mutational analysis of the HSP70i substrate-binding domain established the peptide QPGVLIQVYEG as invaluable for DC activation, and mutant HSP70i could not induce depigmentation. Moreover, mutant HSP70iQ435A bound human DCs and reduced their activation, as well as induced a shift from inflammatory to tolerogenic DCs in mice. HSP70iQ435A-encoding DNA applied months before spontaneous depigmentation prevented vitiligo in mice expressing a transgenic, melanocyte-reactive T cell receptor. Furthermore, use of HSP70iQ435A therapeutically in a different, rapidly depigmenting model after loss of differentiated melanocytes resulted in 76% recovery of pigmentation. Treatment also prevented relevant T cells from populating mouse skin. In addition, ex vivo treatment of human skin averted the disease-related shift from quiescent to effector T cell phenotype. Thus, HSP70iQ435A DNA delivery may offer potent treatment opportunities for vitiligo.

HSP70 modified response against HPV based tumor.

BACKGROUND AND OBJECTIVES: DNA immunization is quite inventive vaccination strategies that engage the direct introduction of plasmid DNA encoding the desired antigen into the host. DNA vaccines expand strong protective responses against tumors. The desired target E7 oncogene products represent a target of choice for the therapeutic vaccination. The efficacy of vaccination is limited and it is often necessary to enhance the immune response by using adjuvant in order to achieve the desired responses. Numerous approaches have been applied to boost the effectiveness, such as the fusion or co-administration of cytokine and co-stimulatory molecules gene. Heat-shock protein 70 a family of chaperone proteins makes possible delivery of non-covalently bound peptide to MHC I molecules and influences peptide-specific CTL responses and cure treated individuals. HSP70 have been proposed as the affective adjuvant and expected to act as an appropriate substitute of both cytokine and co-stimulatory genes. MATERIALS AND METHODS: In the current study, the impact of HSP70 co-delivery and HPV-E7 boosting on cellular immune responses and protection has been investigated by intramuscular injection of mixed DNA constructs. RESULTS: Our results reveal that the target DNA vaccine can influence an E7-specific CTL response, which is imperative in the lysis of infected tumor cells, compared to negative control (p < 0.05). Additionally, treatment of tumor-bearing mice with pcDNA/E7 + HSP70 plasmid generates stronger immune responses and decreased significantly tumor sizes. Immunization with HSP-based vaccine with special target immunogene can induce potent and specific anti-tumor or anti-viral immune responses. CONCLUSIONS: Co-administration of pcDNA/E7 + HSP70 plasmid was immunologically more effective than pcDNA/E7 alone. It was concluded that all the characteristics observed during our investigation demonstrate the potent adjuvant activities of HSP70 and could be an efficient approach to persuade dramatically E7-specific immune responses as future cervical cancer vaccine.  

Druggability of mortalin for cancer and neuro-degenerative disorders.

Mortalin is a member of Hsp70 family of stress chaperones. It was first identified as a protein involved in the senescence of mouse cells. Genetic studies revealed that there are two mouse mortalin alleles coding for two proteins (mot-1 and mot-2) that differ in only two amino acids in the carboxy-terminus, but have contrasting activities. Whereas mot-1 accelerated senescence, mot-2 extended the lifespan of mouse cells in culture. In human cells, only one kind of mortalin protein has been identified so far and is shown to be functionally equivalent to mouse mot-2. Whereas mortalin is enriched in cancer cells and contributes to carcinogenesis, the old age brain disorders show its deficiency. As we demystify its deux de machina, accumulating evidence reveal that mortalin may be "druggable" bidirectionally to either treat cancer or neuro-degenerative disorders.

Functional inclusion bodies produced in bacteria as naturally occurring nanopills for advanced cell therapies.

Inclusion bodies (50-500 nm in diameter) produced in recombinant bacteria can be engineered to contain functional proteins with therapeutic potential. Upon exposure, these protein particles are efficiently internalized by mammalian cells and promote recovery from diverse stresses. Being fully biocompatible, inclusion bodies are a novel platform, as tailored nanopills, for sustained drug release in advanced cell therapies.

Recombinant human Hsp70 protects against lipoteichoic acid-induced inflammation manifestations at the cellular and organismal levels.

It has been previously reported that pretreatment with exogenous heat shock protein 70 (Hsp70) is able to protect cells and animals from the deleterious effects of bacterial lipopolysaccharide (LPS) produced by Gram-negative bacteria. However, the effects of Hsp70 pretreatment on lipoteichoic acid (LTA) challenge resulted from Gram-positive bacteria infection have not been fully elucidated. In this study, we demonstrated that preconditioning with human recombinant Hsp70 ameliorates various manifestations of systematic inflammation, including reactive oxygen species, TNFα, and CD11b/CD18 adhesion receptor expression induction observed in different myeloid cells after LTA addition. Therefore, exogenous Hsp70 may provide a mechanism for controlling excessive inflammatory responses after macrophage activation. Furthermore, in a rat model of LTA-induced sepsis, we demonstrated that prophylactic administration of exogenous human Hsp70 significantly exacerbated numerous homeostatic and hemodynamic disturbances induced by LTA challenge and partially normalized the coagulation system and multiple biochemical blood parameters, including albumin and bilirubin concentrations, which were severely disturbed after LTA injections. Importantly, prophylactic intravenous injection of Hsp70 before LTA challenge significantly reduced mortality rates. Thus, exogenous mammalian Hsp70 may serve as a powerful cellular defense agent against the deleterious effects of bacterial pathogens, such as LTA and LPS. Taken together, our findings reveal novel functions of this protein and establish exogenous Hsp70 as a promising pharmacological agent for the prophylactic treatment of various types of sepsis.

Improved efficacy of therapeutic vaccination with dendritic cells pulsed with tumor cell lysate against hepatocellular carcinoma by introduction of 2 tandem repeats of microbial HSP70 peptide epitope 407-426 and OK-432.

Therapeutic vaccination with dendritic cells (DCs) pulsed with tumor cell lysate vaccine (H-D) represents an attractive approach for hepatocellular carcinoma (HCC) treatment. However, the efficacy of this approach is not most satisfactory for the low levels of T helper 1 (Th1)-type cytokines secretion and weak T cell responses. In this study, in order to increase the potency of H-D, two tandem repeats of microbial HSP70 peptide epitope 407-426 (2mHSP70(407-426), M2) which has been demonstrated to be effective in enhancing DC maturation were applied. The DC vaccine (HM-D) which was HCC tumor cell lysate pulsed with M2 was developed. Nevertheless, the immunotherapeutic effect was still not satisfactory enough even some promotion was obtained. Therefore, OK-432 (OK), which is a useful anti-cancer agent and effectively in stimulating DC maturation, was introduced to HM-D. Our results demonstrated that treatment with the improved DC vaccine which was tumor cell lysate pulsed with M2 and OK (HMO-D), compared with H-D and HM-D, significantly increased cell surface markers (MHC-I and II, CD40, CD80, CD86 and CD11c) expression on DCs, enhanced Th1-type cytokines (IL-12, TNF-α and IFN-γ) production but not Th2-type cytokine (IL-5) production, induced remarkable high levels of lymphocytes proliferation and CD8(+) cytotoxic T-lymphocyte (CTL). Furthermore, immunization with HMO-D effectively reduced tumor progression and enhanced the survival of mice with H22 tumors. Besides, we also found that the capability of M2 in inducing the Th1 cytokines was stronger than OK. In view of these results, HMO-D vaccination provided a novel immunotherapeutic approach for the treatment of HCC.

Tumor antigen delivered by Salmonella III secretion protein fused with heat shock protein 70 induces protection and eradication against murine melanoma.

Attenuated Salmonella typhimurium possess the ability to stimulate innate immune responses and preferentially allocate within the solid tumor. These two main characteristics make attenuated Salmonella one of the most attractive vehicles for development of vaccine and also targeted cancer therapies. However, location of Salmonella prevents the process of antigen presentation. Salmonella Type III secretion system can be utilized to circumvent this problem because this system secretes the protein it encoded outside the cells. Heat shock protein 70 (Hsp70) is referred to as an "immunochaperone" for its capacity to elicit tumor-specific adaptive immune responses in the form of Hsp70-TAA (tumor associated antigen) complex. Hsp70 facilitates the cross-presentation of exogenous antigens through its receptor on antigen-presenting cells and therefore activates an antigen-specific cytotoxic T lymphocyte (CTL) response, which can directly contribute to potent anti-tumor immunity. Here, we designed a novel therapeutic vaccine utilizing the type III secretion system and Hsp70 to deliver and present the tumor-specific antigen. This live recombinant bacteria vaccine, when administrated orally, successfully broke the immune tolerance, induced a specific CTL response against tumor cells, and therefore revealed protective and therapeutic effects against generation and growth of B16F10 melanoma in C57BL/6J mice.

[Therapeutic effects of B and T lymphocyte attenuator extracellular domain and heat shock protein 70 antigen peptide on cervical cancer in mouse model].

OBJECTIVE: To investigate the synergistic therapy effects of B and T lymphocyte attenuator (BTLA) extracellular domain in combination with heat shock protein 70 (HSP70)-TC-1 antigen peptide complex on the mouse model of cervical cancer and the related immunological mechanisms. METHODS: (1) Detecting the BTLA and herpesvirus entry mediator (HVEM) gene expression in the tumor microenvironment after C57BL/6 mice were inoculated with TC-1 tumor cells by realtime PCR; BTLA, HVEM expression on tumor infiltrating lymphocytes cell surface were detected by flow cytometry (fluorescence intensity). (2) According to different treatments, tumor-bearing mice were divided into 5 groups, which was injected with pcDNA3.1 (empty vector plasmid as control), psBTLA (vector plasmid which expresses BTLA extracellular domain), HSP70 (HSP70-TC-1 cell peptide complex), HSP70 + pcDNA3.1 or HSP70 + psBTLA, respectively. The weight of tumor was recorded. The expression of immunoregulatory genes in tumor microenvironment were detected. The change of lymphocyte amount and cytotoxicity were detected too; lymphocyte proliferation activity was measured by tritium thymidine incorporation assay; the concentration of interleukin (IL)2 and interferon-γ (IFN-γ) in supernatants of spleen lymphocyte were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: (1) BTLA gene expression was gradually increased after tumor cells inoculation. The highest expression level was 2.83 ± 0.35 at 14th day, which had statistical significance difference with the 7th day expression of 1.66 ± 0.25 (P < 0.05). While HVEM mRNA expression did not change significantly (P > 0.05). The 7th and 14th day after TC-1 cells inoculation, the average fluorescence intensity of BTLA expression on the surface of tumor infiltrating lymphocytes was 33.5 and 51.8, respectively, in which there was statistically significant difference (P < 0.05); while the difference of HVEM expression was not statistically significant (57.2 vs 49.3, P > 0.05). (2) The 28th day after inoculation, tumor inhibition rate of HSP70 + psBTLA group was 88%, which was significantly higher than other treatment groups (P < 0.05). The 28th day after TC-1 cells inoculation, combination therapy not only promoted IFN-γ and IL-2 gene (3.12 ± 0.71, 3.20 ± 0.62) expression but also reduced transforming growth factor-ß (TGF-ß), Foxp3 and IL-10 expression (0.25 ± 0.03, 0.19 ± 0.03, 0.31 ± 0.04; P < 0.05). It also promoted CD8(+) T lymphocyte infiltration (52 ± 6)/high power field, cytotoxicity (65.5 ± 2.4)%, proliferation (15.0 × 10³ cpm) and cytokine IL-2, IFN-γ secretion (824 ± 51), (1096 ± 112) pg/ml, which were all significantly higher than other groups (P < 0.05). CONCLUSION: The effect of immunotherapy on tumor can be augmented by the combination of psBTLA which expresses extracellular domain of BTLA and HSP70-TC-1 tumor antigen peptide complex, which could improve the expression of the related immunoregulatory genes to establish a much better microenvironment in favor of anti-tumor immune response against the mice model of the cervix carcinoma.

Unexpected deeds of familiar proteins: Interplay of Hsp70, PGRP-S/Tag7 and S100A4/Mts1 in host vs. cancer combat.

We consider the novel means of attack and defense in the host versus cancer combat that involve interactions between widespread multifunctional proteins, focusing on the aspects that may seem paradoxical in the framework of established notions. Particularly, we show that a protein broadly known for its protective functions such as Hsp70 can make a tumoricidal "binary weapon" with another nontoxic protein Tag7 (PGRP-S); that the same Hsp70, a ubiquitous intracellular chaperone, when expressed on the MHC-negative tumor cell surface, can itself be the hallmark of immune evasion rather than a primordial MHC substitute; that a device functionally equivalent to the T-cell receptor (Tag7-Centered Recognizer) can be assembled of components in no way related to the classical pathways of T-cell-mediated immunity, and operate where the orthodox immunosurveillance fails; and that one and the same protein Mts1 (S100A4) under different circumstances may work as "reactive armor" of a tumor cell against humoral agents and as a vital part of the T-cell machinery aimed against immunoevasive cells, i.e., perform both prometastatic and antimetastatic functions.

The versatile stress protein mortalin as a chaperone therapeutic agent.

Age- and stress-induced modulations in chaperone systems result in "chaperono-deficiency" or "chaperon-opulence". Development of modulators, of chaperone function has therefore, become an emerging field in drug development and discovery. This mini-review summarizes (i) the events leading to identification of an Hsp70 family stress chaperone, mortalin, (ii) experimental evidence to its role in old age diseases and cancer, and (iii) proposes it as a chaperono-therapeutic agent. As post-translational modifications and expression changes in mortalin are being explored as a biomarker for cancer, cardiovascular diseases and neurodegeneration, we discuss here how the current tools used in studying mortalin (e.g. antibodies, peptides, ribozymes, antisense and siRNA, recombinant proteins and small molecules etc.) could be creatively applied in a clinical setting to manage stress and to treat various chaperone-based maladies or "chaperonopathies".

[Recombinant heat shock protein 70 induced by adenovirus protects neurons and glial cells against hypoxia/reoxygenation injury].

OBJECTIVE: To investigate the protective effect on neurons and glial cells against hypoxia/ reoxygenation injury with recombinant heat shock protein 70 (HSP70) induced by adenovirus. METHODS: Neurons and glial cells in culture were divided into four groups: three groups were treated with recombinant adenovirus (vAd-HSP70) transfected human HSP70 gene at 24, 48 and 72 hours respectively, and vAd-GFP transfected cell served as control. Cells in different groups were subjected to hypoxia/reoxygenation, then the cell viability was analyzed by methyl thiazolyl tetrazolium (MTT) method, lactate dehydrogenase (LDH) viability was evaluated with LDH staining kit, and cytochrome C (Cyt C) in mitochondria and cytoplasm were assessed by Western blotting. RESULTS: The expression of human HSP70 gene was detected in the vAd-HSP70 transfection group. After hypoxia/reoxygenation treatment, the cell viability in transfected groups was higher than that of control group (all P<0.05), the LDH viability of vAd-HSP70 transfected groups at different time points was 1,480+/-121, 1,023+/-106, and (1,132+/-197) U/L respectively, and they were significantly lower than control group [(1,976+/-190) U/L, all P<0.01]. In transfected groups, the content of Cyt C in mitochondria (0.986+/-0.012, 1.028+/-0.007, 1.014+/-0.008) was significantly higher than control group (0.970+/-0.003, P<0.05 or P<0.01). In contrast, the content of Cyt C in cytoplasm (0.987+/-0.008, 0.960+/-0.005, 0.964+/-0.003) was lower than that of control group (1.011+/-0.005, all P<0.01). The protective effect was especially obvious when the cells were transfected by vAd-HSP70 at 48 hours (all P<0.01). CONCLUSION: The expression of human HSP70 mediated by recombinant adenovirus may protect neurons and glial cells against hypoxia/reoxygenation in vitro.