Defining immunological impact and therapeutic benefit of mild heating in a murine model of arthritis

Ultrasound and neuroinflammation: immune modulation via the heat shock response

Current pharmacological therapeutic approaches targeting chronic inflammation exhibit transient efficacy, often with adverse effects, limiting their widespread use - especially in the context of neuroinflammation. Effective interventions require the consideration of homeostatic function, pathway dysregulation, and pleiotropic effects when evaluating therapeutic targets. Signalling molecules have multiple functions dependent on the immune context, and this complexity results in therapeutics targeting a single signalling molecule often failing in clinical translation. Additionally, the administration of non-physiologic levels of neurotrophic or anti-inflammatory factors can alter endogenous signalling, resulting in unanticipated effects. Exacerbating these challenges, the central nervous system (CNS) is isolated by the blood brain barrier (BBB), restricting the infiltration of many pharmaceutical compounds into the brain tissue. Consequently, there has been marked interest in therapeutic techniques capable of modulating the immune response in a pleiotropic manner; ultrasound remains on this frontier. While ultrasound has been used therapeutically in peripheral tissues - accelerating healing in wounds, bone fractures, and reducing inflammation - it is only recently that it has been applied to the CNS. The transcranial application of low intensity pulsed ultrasound (LIPUS) has successfully mitigated neuroinflammation in vivo, in models of neurodegenerative disease across a broad spectrum of ultrasound parameters. To date, the underlying biological effects and signalling pathways modulated by ultrasound are poorly understood, with a diverse array of reported molecules implicated. The distributed nature of the beneficial response to LIPUS implies the involvement of an, as yet, undetermined upstream signalling pathway, homologous to the protective effect of febrile range hyperthermia in chronic inflammation. As such, we review the heat shock response (HSR), a protective signalling pathway activated by thermal and mechanical stress, as the possible upstream regulator of the anti-inflammatory effects of ultrasound.

Transient Mild Photothermia Improves Therapeutic Performance of Oral Nanomedicines with Enhanced Accumulation in the Colitis Mucosa

The treatment outcomes of oral medications against ulcerative colitis (UC) have long been restricted by low drug accumulation in the colitis mucosa and subsequent unsatisfactory therapeutic efficacy. Here, high-performance pluronic F127 (P127)-modified gold shell (AuS)-polymeric core nanotherapeutics loading with curcumin (CUR) is constructed. Under near-infrared irradiation, the resultant P127-AuS@CURs generate transient mild photothermia (TMP; ≈42 °C, 10 min), which facilitates their penetration through colonic mucus and favors multiple cellular processes, including cell internalization, lysosomal escape, and controlled CUR release. This strategy relieves intracellular oxidative stress, improves wound healing, and reduces immune responses by polarizing the proinflammatory M1-type macrophages to the anti-inflammatory M2-type. Upon oral administration of hydrogel-encapsulating P127-AuS@CURs plus intestinal intralumen TMP, their therapeutic effects against acute and chronic UC are demonstrated to be superior to those of a widely used clinical drug, dexamethasone. The treatment of P127-AuS@CURs (+ TMP) elevates the proportions of beneficial bacteria (e.g., Lactobacillus and Lachnospiraceae), whose metabolites can also mitigate colitis symptoms by regulating genes associated with antioxidation, anti-inflammation, and wound healing. Overall, the intestinal intralumen TMP offers a promising approach to enhance the therapeutic outcomes of noninvasive medicines against UC.

Heating Pretreatment of the Recipient Site Enhances Survival of Transplanted Fat in a Mouse Model

BACKGROUND

Despite several studies about the preparation of the recipient site in fat grafting, optimizing techniques with clinical usefulness is still necessary. Through previous animal studies reporting that heat can increase tissue vascular endothelial growth factor and vascular permeability, the authors hypothesize that pretreatment heating of the recipient site will increase retention of grafted fat.

METHODS

Twenty 6-week-old female BALB/c mice had two pretreatment sites on their back, one for the experimental temperatures (44°C and 48°C) and the other for the control. A digitally controlled aluminum block was used to apply the contact thermal damage. Human fat (0.5 mL) was grafted on each site and harvested on days 7, 14, and 49. The percentage volume and weight, histologic changes, and peroxisome proliferator-activated receptor gamma expression, a key regulator of adipogenesis, were measured by the water displacement method, light microscopy, and quantitative real-time polymerase chain reaction, respectively.

RESULTS

The harvested percentage volumes were 74.0% ± 3.4%, 82.5% ± 5.0%, and 67.5% ± 9.6% for the control, 44°C-pretreatment, and 48°C-pretreatment groups, respectively. The percentage volume and weight of the 44°C-pretreatment group was higher than the other groups ( P < 0.05). The 44°C-pretreatment group exhibited significantly higher integrity with fewer cysts and vacuoles than the other groups. Both heating pretreatment groups showed markedly higher rates of vascularity than the control group ( P < 0.017), and also increased the expression of peroxisome proliferator-activated receptor gamma over two-fold.

CONCLUSION

Heating preconditioning of the recipient site during fat grafting can increase the retention volume and improve the integrity, which is partly explained by increased adipogenesis in a short-term mouse model.

CLINICAL RELEVANCE STATEMENT

Tanning could be an alternative pretreatment for fat grafting.

Fever-range whole body hyperthermia leads to changes in immune-related genes and miRNA machinery in Wistar rats

OBJECTIVE

Fever is defined as a rise in body temperature upon disease. Fever-range hyperthermia (FRH) is a simplified model of fever and a well-established medical procedure. Despite its beneficial effects, the molecular changes induced by FRH remain poorly characterized. The aim of this study was to investigate the influence of FRH on regulatory molecules such as cytokines and miRNAs involved in inflammatory processes.

METHODS

We developed a novel, fast rat model of infrared-induced FRH. The body temperature of animals was monitored using biotelemetry. FRH was induced by the infrared lamp and heating pad. White blood cell counts were monitored using Auto Hematology Analyzer. In peripheral blood mononuclear cells, spleen and liver expression of immune-related genes (IL-10, MIF and G-CSF, IFN-γ) and miRNA machinery (DICER1, TARBP2) was analyzed with RT-qPCR. Furthermore, RT-qPCR was used to explore miRNA-155 levels in the plasma of rats.

RESULTS

We observed a decrease in the total number of leukocytes due to lower number of lymphocytes, and an increase in the number of granulocytes. Furthermore, we observed elevated expressions of DICER1, TARBP2 and granulocyte colony-stimulating factor (G-CSF) in the spleen, liver and PBMCs immediately following FRH. FRH treatment also had anti-inflammatory effects, evidenced by the downregulation of pro-inflammatory macrophage migration inhibitor factor (MIF) and miR-155, and the increased expression of anti-inflammatory IL-10.

CONCLUSION

FRH affects the expression of molecules involved in inflammatory processes leading to alleviated inflammation. We suppose these effects may be miRNAs-dependent and FRH can be involved in therapies where anti-inflammatory action is needed.

A novel anti-TNF-α drug ozoralizumab rapidly distributes to inflamed joint tissues in a mouse model of collagen induced arthritis

In clinical studies, the next-generation anti-tumor necrosis factor-alpha (TNF-α) single domain antibody ozoralizumab showed high clinical efficacy shortly after the subcutaneous injection. To elucidate the mechanism underlying the rapid onset of the effects of ozoralizumab, we compared the biodistribution kinetics of ozoralizumab and adalimumab after subcutaneous injection in an animal model of arthritis. Alexa Fluor 680-labeled ozoralizumab and adalimumab were administered by subcutaneous injection once (2 mg/kg) at five weeks after induction of collagen-induced arthritis (CIA) in an animal arthritis model. The time-course of changes in the fluorescence intensities of the two compounds in the paws and serum were evaluated. The paws of the CIA mice were harvested at four and eight hours after the injection for fluorescence microscopy. Biofluorescence imaging revealed better distribution of ozoralizumab to the joint tissues than of adalimumab, as early as at four hours after the injection. Fluorescence microscopy revealed a greater fluorescence intensity of ozoralizumab in the joint tissues than that of adalimumab at eight hours after the injection. Ozoralizumab showed a significantly higher absorption rate constant as compared with adalimumab. These results indicate that ozoralizumab enters the systemic circulation more rapidly and is distributed to the target tissues earlier and at higher levels than conventional IgG antibodies. Our investigation provides new insight into the mechanism underlying the rapid onset of the effects of ozoralizumab in clinical practice.

Thermochemotherapy Meets Tissue Engineering for Rheumatoid Arthritis Treatment

Rheumatoid arthritis (RA) is an autoimmune disease that progresses from inflammation to cartilage destruction. Inspired by the similar characteristics of inflammatory granulation tissue to those of tumors, the newly emerged tumor therapy called thermochemotherapy is proposed to treat RA. Meanwhile, the repair of cartilage injury via tissue engineering is paid attention simultaneously. A first‐line antirheumatic drug (MTX; methotrexate) and transforming growth factor β1 (TGF‐β1) are loaded in nano‐Fe3O4 composite chitosan‐polyolefin to construct a multifunctional hydrogel (DN‐Fe‐MTX‐TGFβ1). The mechanical properties of the hydrogel are equivalent to that of articular cartilage to guarantee its role as a scaffold. A long‐term release ability and the magnetocaloric properties of the hydrogel assure its effect to provide sustained local thermochemotherapy. The effective ability of the hydrogel for both anti‐inflammation and cartilage repair is demonstrated. This work indicates a promising way to combine thermochemotherapy and tissue engineering for the effective treatment of RA for the first time.

From traditional to novel treatment of arthritis: a review of recent advances in nanotechnology-based thermal therapy

Arthritis has been a heavy burden on the economy and society at large. Recently, nanomaterials that can convert near-infrared light into localized heat have demonstrated better targeting to arthritic joints, fewer side effects, ease of combined application with current therapeutics and enhanced efficacy for arthritis treatment. In this review, the authors summarize traditional thermal therapies for arthritis treatment and their molecular mechanisms and discuss the advantages and applications of nanotechnology-based thermal therapies for arthritis treatment. In conclusion, nanotechnology-based thermal therapies are effective alternatives or adjuvant strategies to the current pharmacological treatment of arthritis. Future clinical translation of thermal therapies could benefit from research elucidating their mechanisms and standardizing their parameters to optimize efficacy.

Temperature as a modulator of the gut microbiome: what are the implications and opportunities for thermal medicine?

There is substantial research being conducted on the relationships between the gut microbiome, the immune response and health and disease. Environmental temperature and heat stress are known to modify the gut microbiome. Changes in core temperature have been linked, in multiple phyla, to altered microbiome composition and function. This raises the question of whether local/regional or whole body thermal therapies which target tumors in the abdomen, peritoneal cavity, or pelvis influence the gut microbiome. To date, there is little information on whether thermal therapy exerts positive or negative effects on the microbiome. This is an intriguing question since there is growing interest in the immunological impact of various thermal therapies. The goal of this brief review is to highlight research on how environmental conditions, particularly temperature (internal as well as external temperatures) influences the gut microbiome. Given the potential for temperature shifts to modulate gut microbe function and composition, it is likely that various forms of thermal therapy, including hyperthermic intraperitoneal chemotherapy (HIPEC), deep regional, and whole body hyperthermia influence the microbiome in ways that are currently not appreciated. More research is needed to determine whether thermal therapy induced changes in the microbiome occur, and whether they are beneficial or detrimental to the host. Currently, although approaches to microbiome modification such as dietary intervention, fecal transfer, probiotics and prebiotics are being developed, the potential of temperature manipulation has, as yet, not been explored. Therefore, new research could reveal whether perturbations of the microbiome composition that have negative health consequences (dysbiosis) could be an important target for treatment by thermal medicine.

DNAJA4 deficiency enhances NF-kappa B-related growth arrest induced by hyperthermia in human keratinocytes

BACKGROUND

Hyperthermia is an effective treatment against cancer and human papillomavirus (HPV) infection. Previous studies have shown that heat shock proteins are crucial to the action of hyperthermia.

OBJECTIVES

To examine the effects of hyperthermia in combination with DNAJA4-deficiency on human keratinocytes and Condyloma acumunatum (CA) tissues.

METHODS

HaCaT cells were subjected to 44°C (compared to 37°C) waterbath for 30min for stimulation. Foreskin or CA tissues obtained from patients undergoing circumcision or pathological examination were bisected and subjected to similar treatments. DNAJA4-knockout (KO) HaCaT cells were generated with CRISPR/Cas9 technology. mRNA and protein expressions were determined using rt-qPCR and western-blotting. Cell cycle distribution, apoptosis and senescence were analyzed by flow cytometry.

RESULTS

DNAJA4 was induced in HaCaT cells, foreskin and CA tissues subjected to hyperthermia at both transcriptional and translational levels. NF-kB,³ was activated by hyperthermia in HaCaT cells, and further enhanced by DNAJA4-deficiency. Transcription of TNF-α⁴; IL-1B,⁵ TNFAIP3⁶ and IL-8⁷ were induced in HaCaT cells subjected to hyperthermia. DNAJA4-knockout promoted transcriptions of TNF-α and IL-1B, whereas decreased that of TNFAIP3 and IL-8. Reduced cell survival, proliferation and viability were demonstrated using flow cytometry and MTS assays. Furthermore, NF-kB inhibitors reversed most of the phenotypes observed.

CONCLUSIONS

Hyperthermia reduced HaCaT cell proliferation and promoted cytokine expressions responsible for anti-viral activity, mainly through a NF-kB dependent pathway. DNAJA4-deficiency enhanced the activation of NF-kB by hyperthermia in HaCaT cells, indicating that DNAJA4 may be a promising therapeutic target for use in the treatment of cutaneous HPV infections.

A review of immune therapy in cancer and a question: can thermal therapy increase tumor response?

Immune therapy is a successful cancer treatment coming into its own. This is because checkpoint molecules, adoptive specific lymphocyte transfer and chimeric antigen T-cell (CAR-T) therapy are able to induce more durable responses in an increasing number of malignancies compared to chemotherapy. In addition, immune therapies are able to treat bulky disease, whereas standard cytotoxic therapies cannot treat large tumour burdens. Checkpoint inhibitor monoclonal antibodies are becoming widely used in the clinic and although more complex, adoptive lymphocyte transfer and CAR-T therapies show promise. We are learning that there are nuances to predicting the successful use of the checkpoint inhibitors as well as to specific-antigen adoptive and CAR-T therapies. We are also newly aware of a here-to-fore unrealised natural force, the status of the microbiome. However, despite better understanding of mechanisms of action of the new immune therapies, the best responses to the new immune therapies remain 20-30%. Likely the best way to improve this somewhat low response rate for patients is to increase the patient's own immune response. Thermal therapy is a way to do this. All forms of thermal therapy, from fever-range systemic thermal therapy, to high-temperature HIFU and even cryotherapy improve the immune response pre-clinically. It is time to test the immune therapies with thermal therapy in vivo to test for optimal timing of the combinations that will best enhance tumour response and then to begin to test the immune therapies with thermal therapy in the clinic as soon as possible.

Thermoregulation as a disease tolerance defense strategy

Physiological responses that occur during infection are most often thought of in terms of effectors of microbial destruction through the execution of resistance mechanisms, due to a direct action of the microbe, or are maladaptive consequences of host-pathogen interplay. However, an examination of the cellular and organ-level consequences of one such response, thermoregulation that leads to fever or hypothermia, reveals that these actions cannot be readily explained within the traditional paradigms of microbial killing or maladaptive consequences of host-pathogen interactions. In this review, the concept of disease tolerance is applied to thermoregulation during infection, inflammation and trauma, and we discuss the physiological consequences of thermoregulation during disease including tissue susceptibility to damage, inflammation, behavior and toxin neutralization.

Fever and the thermal regulation of immunity: the immune system feels the heat

Fever is a cardinal response to infection that has been conserved in warm-blooded and cold-blooded vertebrates for more than 600 million years of evolution. The fever response is executed by integrated physiological and neuronal circuitry and confers a survival benefit during infection. In this Review, we discuss our current understanding of how the inflammatory cues delivered by the thermal element of fever stimulate innate and adaptive immune responses. We further highlight the unexpected multiplicity of roles of the pyrogenic cytokine interleukin-6 (IL-6), both during fever induction and during the mobilization of lymphocytes to the lymphoid organs that are the staging ground for immune defence. We also discuss the emerging evidence suggesting that the adrenergic signalling pathways associated with thermogenesis shape immune cell function.