Development of Hsp90 inhibitor to regulate cytokine storms in excessive delayed- and acute inflammation.

BACKGROUND: The surplus cytokines remaining after use in the early stages of the inflammatory response stimulate immune cells even after the response is over, causing a secondary inflammatory response and ultimately damaging the host, which is called a cytokine storm. Inhibiting heat shock protein 90 (Hsp90), which has recently been shown to play an important role in regulating inflammation in various cell types, may help control excessive inflammatory responses and cytokine storms. METHODS: We discovered an anti-inflammatory compound by measuring the inhibitory effect of CD86 expression on spleen DCs (sDCs) using the chemical compounds library of Hsp90 inhibitors. Subsequently, to select the hit compound, the production of cytokines and expression of surface molecules were measured on the bone marrow-derived DCs (BMDCs) and peritoneal macrophages. Then, we analyzed the response of antigen-specific Th1 cells. Finally, we confirmed the effect of the compound using acute lung injury (ALI) and delayed-type hypersensitivity (DTH) models. RESULTS: We identified Be01 as the hit compound, which reduced CD86 expression the most in sDCs. Treatment with Be01 decreased the production of pro-inflammatory cytokines (IL-6, TNF-α, and IL-1ß) in BMDC and peritoneal macrophages stimulated by LPS. Under the DTH model, Be01 treatment reduced ear swelling and pro-inflammatory cytokines in the spleen. Similarly, Be01 treatment in the ALI model decreased neutrophil infiltration and lower levels of secreted cytokines (IL-6, TNF-α). CONCLUSIONS: Reduction of CD80 and CD86 expression on DCs by Be01 indicates reduced secondary inflammatory response by Th1 cells, and reduced release of pro-inflammatory cytokines by peritoneal macrophages may initially control the cytokine storm.

Evaluation of Antineoplastic Delayed-Type Hypersensitivity Skin Reactions In Vitro.

Delayed-type hypersensitivity (DTH) is caused by a broad number of drugs used in clinic, and antineoplastic drugs show an elevated proportion of DTH, which potentially affects the quality of life of patients. Despite the serious problem and the negative economic impact deriving from market withdrawal of such drugs and high hospitalization costs, nowadays, there are no standard validated methods in vitro or in vivo to evaluate the sensitizing potential of drugs in the preclinical phase. Enhanced predictions in preclinical safety evaluations are really important, and for that reason, the aim of our work is to adapt in vitro DPRA, ARE-Nrf2 luciferase KeratinoSensTM, and hCLAT assays for the study of the sensitizing potential of antineoplastic agents grouped by mechanism of action. Our results reveal that the above tests are in vitro techniques able to predict the sensitizing potential of the tested antineoplastics. Moreover, this is the first time that the inhibition of the VEGFR1 pathway has been identified as a potential trigger of DTH.

Evidence for transfer of maternal antigen specific cellular immunity against Mycobacterium avium ssp. paratuberculosis via colostrum in a goat twin model.

Colostrum intake is one of the most important factors in neonatal health in ruminants, mainly because of its unique immunological properties. Both in practice as well as in research, the attention of lactogenic immunity is focused on the importance of colostral antibodies and less attention is given to the functional role of maternal cells in colostrum. Here we study the transfer of maternal leukocytes via colostrum and the functionality in goat kids. In experiment 1, twenty twin pairs of goat kids from dams previously immunized with an inactivated Mycobacterium avium subsp. paratuberculosis (MAP) vaccine were fed maternal colostrum from their dam (kid 1) or pasteurized and frozen/thawed bovine colostrum (kid 2). The presence of cell mediated immune response (CMIR) against Mycobacterium avium antigens in the kids was assessed using intradermal skin testing with PPD-A tuberculin. Linear mixed effect models showed an increase in skin thickness in response to intradermal PPD-A injection in maternal colostrum fed kids compared to bovine colostrum fed kids. After intradermal PPD-A application, serum concentration of MAP specific antibodies increased in kids fed maternal colostrum, indicating antigen specific activation of the adaptive immune system. We did not detect a similar increase in antibodies in the kids fed bovine colostrum. In experiment 2, a more reductionistic approach was applied to specifically study the effects of the transfer of maternal colostral leukocytes on CMIR in goat kids. Similar to experiment 1, twin kids from MAP immunized dams were randomly divided over two groups. The experimental group received colostrum replacer supplemented with fluorescently labelled colostral cells of the dam and the control group received colostrum replacer only. No difference in skin response following intradermal PPD-A injection was observed between both groups of kids. Histologic examination of the skin at the intradermal injection site did not show fluorescently labelled cells. In conclusion, in our initial experiment we observed an antigen specific CMIR in goat kids fed fresh colostrum with colostral leukocytes from vaccinated dams. The lack of a DTH response in kids fed colostrum replacer supplemented with maternal colostrum derived leukocytes indicated that the complete colostral matrix is probably required for colostrum leukocytes to transfer across the intestinal epithelial barrier and modulate the neonatal immune response. In line with earlier studies, our results indicate that caprine maternal leukocytes present in colostrum can functionally contribute to the newborns' early adaptive immune responses adding to the importance of colostrum feeding in ruminant neonates.

Orally Administered Exosomes Suppress Mouse Delayed-Type Hypersensitivity by Delivering miRNA-150 to Antigen-Primed Macrophage APC Targeted by Exosome-Surface Anti-Peptide Antibody Light Chains.

We previously discovered suppressor T cell-derived, antigen (Ag)-specific exosomes inhibiting mouse hapten-induced contact sensitivity effector T cells by targeting antigen-presenting cells (APCs). These suppressive exosomes acted Ag-specifically due to a coating of antibody free light chains (FLC) from Ag-activated B1a cells. Current studies are aimed at determining if similar immune tolerance could be induced in cutaneous delayed-type hypersensitivity (DTH) to the protein Ag (ovalbumin, OVA). Intravenous administration of a high dose of OVA-coupled, syngeneic erythrocytes similarly induced CD3+CD8+ suppressor T cells producing suppressive, miRNA-150-carrying exosomes, also coated with B1a cell-derived, OVA-specific FLC. Simultaneously, OVA-immunized B1a cells produced an exosome subpopulation, originally coated with Ag-specific FLC, that could be rendered suppressive by in vitro association with miRNA-150. Importantly, miRNA-150-carrying exosomes from both suppressor T cells and B1a cells efficiently induced prolonged DTH suppression after single systemic administration into actively immunized mice, with the strongest effect observed after oral treatment. Current studies also showed that OVA-specific FLC on suppressive exosomes bind OVA peptides suggesting that exosome-coating FLC target APCs by binding to peptide-Ag-major histocompatibility complexes. This renders APCs capable of inhibiting DTH effector T cells. Thus, our studies describe a novel immune tolerance mechanism mediated by FLC-coated, Ag-specific, miRNA-150-carrying exosomes that act on the APC and are particularly effective after oral administration.

Withania somnifera chemotype NMITLI 101R significantly increases the efficacy of antileishmanial drugs by generating strong IFN-γ and IL-12 mediated immune responses in Leishmania donovani infected hamsters.

BACKGROUND: Withania somnifera (L.) Dunal (Solanaceae), commonly known as Ashwagandha, is one of the most important medicinal plant in the traditional Indian medical systems. Pharmacological studies have established that root extracts of W. somnifera contain several bioactive constituents called withanolides. The plant has long been used for its several beneficial properties and recently as an immunomodulator. HYPOTHESIS/PURPOSE: A combination therapy including a potential and safe immunostimulant with lower doses of effective drug, which can reduce the parasitic burden and simultaneously can produce an enhancement of adaptive immunity, has proven to be significantly a more effective approach than immunotherapy or drug therapy alone. STUDY DESIGN: Evaluation of the immunostimulatory effect of W. somnifera chemotype NMITLI 101R when used in combination with ED50 doses of antileishmanial drugs in Leishmania donovani infected hamsters. METHODS: Infected animals were administered with chemotype 101R(30mg/kg × 15 days) either alone or in combination with ED50 doses of miltefosine (10mg/kg × 5 days), paromomycin (30mg/kg × 5 days) or amphotericin B (0.5mg/kg × 5 days). The treated animals were euthanized on days 30 and 60 post-treatment (p.t.) and checked for parasite clearance, delayed type hypersensitivity (DTH) response, cytokine and inducible nitric oxide synthase levels by real-time PCR, nitric oxide (NO) production, reactive oxygen species (ROS) generation, lymphoproliferative and antibody responses. RESULTS: The group of animals that received 101R and ED50 dose of miltefosine showed optimum inhibition of parasite multiplication (∼98%) by day 60 p.t. followed by the group that received 101R plus paromomycin (∼94%) and 101R plus amphotericin B (∼93%). The efficacy was well supported by the increased inducible NO synthase mRNA transcript, strong IFN-γand IL-12 mediated Th1 immune responses and significantly suppressed levels of Th2 cytokines (IL-4, IL-10 and TGF-ß). Additionally, same therapy also induced significant increase in the level of NO production, ROS generation, Leishmania specific IgG2 antibody along with profound DTH and strong T-cell responses as compared with all the other treated groups. CONCLUSION: Our results suggest that combination of chemotype 101R with ED50 doses of antileishmanial drugs may provide a promising alternative for the cure of visceral leishmaniasis with significant restoration of the host immune response.

Production of endocannabinoids by activated T cells and B cells modulates inflammation associated with delayed-type hypersensitivity.

Endocannabinoids are endogenous ligands for the cannabinoid (CB) receptors which include anandamide (AEA) and 2-arachidonyl glycerol (2-AG). 2-AG has been linked to inflammation due to its elevated expression in animal models of autoimmunity and hypersensitivity. However, administration of exogenous 2-AG has been shown to suppress inflammation making its precise role unclear. In the current study, we investigated the role of 2-AG following immunization of C57BL/6 (BL6) mice with methylated BSA (mBSA) antigen, which triggers both delayed-type hypersensitivity (DTH) and antibody response. We found that while naïve T cells and B cells expressed low levels of 2-AG, expression significantly increased upon activation. Furthermore, mBSA-immunized mice exhibited higher 2-AG concentration than naïve mice. Exogenous 2-AG treatment (40 mg/kg) in mBSA-immunized mice led to reduced DTH response, and decreased Th1 and Th17-associated cytokines including IL-6, IL-2, TNF-α, and the IgG response. Addition of 2-AG to activated popliteal lymph node (PopLN) cell cultures also inhibited lymphocyte proliferation. Together, these data show for the first time that activated T and B cells produce 2-AG, which plays a negative regulatory role to decrease DTH via inhibition of T-cell activation and proliferation. Moreover, these findings suggest that exogenous 2-AG treatment can be used therapeutically in Th1- or Th17-driven disease.

Contact Hypersensitivity.

Contact hypersensitivity (CHS) is a simple in vivo assay of cell-mediated immune function in which exposure of epidermal and dermal cells to exogenous haptens results in a delayed-type hypersensitivity (DTH) reaction that can be measured and quantified. Epidermal Langerhans cells and dermal dendritic cells are the critical antigen-presenting cells in this reaction which initiate sensitization to haptens by presenting antigens to CD4- and CD8-bearing T lymphocytes which, in turn, secrete cytokines and recruit other cells to the site of the reaction. In the protocol described here, mice are shaved and the skin of their abdomens is exposed to a hapten. After 5 or 6 days (the afferent phase), the baseline ear thickness is measured prior to initiation of the efferent phase. Finally, the ear is treated epicutaneously with the hapten solution and ear thickness is measured in ∼24 hr. The magnitude of the ear swelling reaction after allergen treatment reflects the strength of the immune response.

Safety and skin delayed-type hypersensitivity response in vervet monkeys immunized with Leishmania donovani sonicate antigen delivered with adjuvants / Segurança e reação de hipersensibilidade tardia na pele de macacos vervet imunizados com antígeno sonicado de Leishmania donovani junto com adjuvantes

In this study, we report on the safety and skin delayed-type hypersensitivity (DTH), responses of the Leishmania donovani whole cell sonicate antigen delivered in conjunction with alum-BCG (AlBCG), Montanide ISA 720 (MISA) or Monophosphoryl lipid A (MPLA) in groups of vervet monkeys. Following three intradermal injections of the inoculums on days 0, 28 and 42, safety and DTH responses were assessed. Preliminary tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) levels were also measured and these were compared with DTH. Only those animals immunized with alum-BCG reacted adversely to the inoculum by producing ulcerative erythematous skin indurations. Non-parametric analysis of variance followed by a post-test showed significantly higher DTH responses in the MISA+Ag group compared with other immunized groups (p < 0.001). The MPLA+Ag group indicated significantly lower DTH responses to the sonicate antigen compared with the AlBCG+Ag group. There was a significant correlation between the DTH and cytokine responses (p < 0.0001). Based on this study we conclude that Leishmania donovani sonicate antigen containing MISA 720 is safe and is associated with a strong DTH reaction following immunization.

Neste estudo reportamos segurança e resposta de hipersensibilidade tardia (DTH) do antígeno sonicado de células totais de Leishmania donovani introduzidos juntamente com alume-BCG (AIBCG) Montanide ISA 720 (MISA) ou lípide A monofosforilado (MPLA) em grupos de macacos vervet. Depois de três injeções intradérmicas do inóculo nos dias 0, 28 e 42 segurança e resposta DTH foram avaliados. Preliminarmente níveis de fator de necrose tumoral alfa (TNF-α) e interferon gama (IFN-γ) foram também medidos e comparados com o DTH. Somente os animais imunizados com alume-BCG reagiram de maneira diversa ao inóculo produzindo indurações ulceradas e eritematosas na pele. Análise não paramétrica de variação seguida por um teste posterior mostraram resposta significantemente mais alta do DTH no grupo MISA + Ag quando comparado com outros grupos imunizados (p < 0.001). O grupo MPLA + Ag demonstrou resposta DTH significantemente menor do antígeno sonicado comparado com o grupo AIBCG + Ag. Houve correlação significante entre o DTH e a resposta às citocinas (p < 0.0001). Baseados neste estudo concluímos que o antígeno sonicado de Leishmania donovani contendo MISA 720 é seguro e está associado com forte reação DTH após imunização.

Coptis chinensis Extract Inhibits the Production of Inflammatory Mediators and Delayed Type Hypersensitivity in Mice

BACKGROUND: Coptis chinensis rhizome has been used as a medicinal herb in traditional Oriental medicine. We investigated the effects of Coptis chinensis extract on inflammatory mediators and delayed type hypersensitivity in mice. METHODS: The inhibitory effect of ethanolic extract of Coptis chinensis (CCE) on cell proliferation was evaluated using MTS assay. The lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and the Con A-activated mouse splenocytes were cultured with various concentrations of CCE. Total nitric oxide (NO) production was determined by Griess reaction. The amounts of secreted prostaglandine E2 (PGE(2)), interleukin (IL)-2 and IFN-gamma were measured by ELISA. To investigate the in vivo anti-inflammatory effect of CCE, oxazolone-induced delayed type hypersensitivity (DTH) model was used. RESULTS: The CCE at 100 microgram/ml significantly blocked the LPS-induced production of pro-inflammatory mediators (NO and PGE) in RAW264.7 macrophages. Also, it significantly inhibited cell proliferation and cytokine (IL-2 and IFN-gamma) production in splenocytes. Furthermore, when splenocytes from CCE fed mice (200 mg/kg for 2 weeks) were activated with Con A, cell proliferation and cytokine production were significantly inhibited. In addition, CCE decreased in vivo inflammation in oxazolone-induced DTH model mice. CONCLUSION: We suggest that Coptis chinensis can be used as an anti-inflammatory drug by exerting an inhibitory effect in inflammatory mediator- and cell-mediated inflammation.

Coptis chinensis Extract Inhibits the Production of Inflammatory Mediators and Delayed Type Hypersensitivity in Mice

BACKGROUND: Coptis chinensis rhizome has been used as a medicinal herb in traditional Oriental medicine. We investigated the effects of Coptis chinensis extract on inflammatory mediators and delayed type hypersensitivity in mice. METHODS: The inhibitory effect of ethanolic extract of Coptis chinensis (CCE) on cell proliferation was evaluated using MTS assay. The lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and the Con A-activated mouse splenocytes were cultured with various concentrations of CCE. Total nitric oxide (NO) production was determined by Griess reaction. The amounts of secreted prostaglandine E2 (PGE(2)), interleukin (IL)-2 and IFN-gamma were measured by ELISA. To investigate the in vivo anti-inflammatory effect of CCE, oxazolone-induced delayed type hypersensitivity (DTH) model was used. RESULTS: The CCE at 100 microgram/ml significantly blocked the LPS-induced production of pro-inflammatory mediators (NO and PGE) in RAW264.7 macrophages. Also, it significantly inhibited cell proliferation and cytokine (IL-2 and IFN-gamma) production in splenocytes. Furthermore, when splenocytes from CCE fed mice (200 mg/kg for 2 weeks) were activated with Con A, cell proliferation and cytokine production were significantly inhibited. In addition, CCE decreased in vivo inflammation in oxazolone-induced DTH model mice. CONCLUSION: We suggest that Coptis chinensis can be used as an anti-inflammatory drug by exerting an inhibitory effect in inflammatory mediator- and cell-mediated inflammation.

The Changes of Cell Mediated Immunity Correlated with Severity of Head Injury

Severe head injury results in the suppression of cellular immunity associated with dysfunctioning of effector lymphocytes, such as helper T cells(CD4) (and cytotoxic T cells(CD8). Despite progress in the management of increased intracranial pressure following head injury, infection remains the most common complication and the primary cause of prolonged hospitalization and death. This study attempts to assess the cellular immune function following head injury according to the degree of severity, and to establish the clinically available parameters of cell mediated immune(CMI) function, which can then be used for coherent prediction of infection risk. Eighteem head injury patients without severe systemic injury, who divided into three subgroups depending on the severity of head injury, were estimated with the use of CMI multitest kit(Merieux Institute, France) to test delayed-type hypersensitivity(DTH) and enumerated the circulating lymphocyte subpopulation(pan T-cell marker CD3, helper T cell marker CD4, cytotoxic T cell marker CD8 and B-cell marker CD19) on the 1st, 7th, and 21th day of injury. Patients were monitored for evidence of infection for this period. Fourteen patients had no reaction to any antigens of the DTH skin test(anergy) and the remaining four patients had also some degree of anergy. Seven patients became infected and all of them were anergic. There were significant decrease of circulating effector T lymphocytes, both CD4-positive and CD8-positive cells, within 24 hours of injury in the mild as well as the moderate and severe head injury group. CD4-positive cells were nearly completely recovered by the 7th day of injury. CD8-positive cells had sustained significant decrease even after 3 weeks of injury. There was no significant change in pan T-cells(CD3-positive cells) and B-cells(CD19-positive cells). The results suggest that DTH skin test and effector T cell enumeration are both relatively simple and highly sensitive parameters for monitoring CMI function. Especially, anergy of DTH skin test can be used for indicator to predict risk of infection. Mild as well as moderate and severe head injuries may result in the suppression of cellular immunity associated with the dysfunctioning of effector T cell.

The preparation of type Ⅱ collagen induced arthritis model in mice / 中国药理学通报

AIM To establish the model of type Ⅱ collagen(CⅡ) induced arthritis in mice. METHODS The type Ⅱ collagen induced arthritits(CIA) mice were induced by intradermal injection with CⅡ and complete Freund adjnvant emulsion. RESULITS In comparison with control mice, the arthritic swelling and index were significant increased. The responses of CⅡ induced delayed type hypersensitivity were remarkably positive, and IgG anti bodies to CⅡ in serum could be detected in CIA mice. CONCLUSION The model CIA mice was successfully established.

REGULATORY EFFECTS OF CPP ON CELL-MEDIATED IMMUNITY IN MICE / 中国药理学通报

Codnopsispilosula polysaccharides (CPP) , which administered intra-peritoneally 200mg/kg?d-1 for 5 d or 8 d in mice, enhanced thephagocytic activity of peritoneal macrophages on chiken RBC, the erythrocyte (E)rosette formation of thymus T lymphocyte and the clearance rate of charcoal particles in normal mice and antagonized the inhibition of E rosette formation and of peritoneal phagocytic activity caused by cyclophosphamide ( CY ) or hydrocortisone ( HCT ) . It inhibited the delayed type hypersensitivity ( DT H ) induced by DNCB and enhanced DT H induced by dexamethasons ( DMS ) . It has regulatory important signification in resisting decrepitude.