Inhibition Of Lymphocyte Activation Research Articles

Enhanced potent immunosuppression of intracellular adipose tissue-derived stem cell extract by priming with three-dimensional spheroid formation

Immunomodulatory properties of mesenchymal stem cells are widely studied, supporting the use of MSCs as cell-based therapy in immunological diseases. This study aims to generate cell-free MSC extract and improves their immunomodulatory potential. Intracellular extracts were prepared from adipose-derived stem cells (ADSC) spheroid via a freeze-thawing method. The immunomodulatory capacities of ADSC spheroid extracts were investigated in vitro, including lymphocyte proliferation, T regulatory cell expansion, and macrophage assays. A comparative study was conducted with ADSC monolayer extract. The key immunomodulatory mediators presented in ADSC extract were identified. The results revealed that ADSC spheroid extract could suppress lymphocyte activation while enhancing T regulatory cell expansion. Immunomodulatory molecules such as COX-2, TSG-6, and TGF-β1 were upregulated in ADSC priming via spheroid culture. Selective inhibition of COX-2 abrogates the effect of ADSC extract on inducing T regulatory cell expansion. Thus, ADSC spheroid extract gains high efficacy in regulating the immune responses which are associated in part by COX-2 generation. Furthermore, ADSC spheroid extract possessed a potent anti-inflammation by manipulation of TNF-α production from LPS-activated macrophage. Our current study has highlighted the opportunity of using cell-free extracts from adipose tissue-derived mesenchymal stem cells spheroid as novel immunomodulators for the treatment of immunological-associated diseases.

Antiproliferative and immunomodulative potential of Citrullus colocynthis and its bioactive compounds in human lymphocytes and lung cells

Ethnopharmacological relevanceCitrullus colocynthis (L.) Schrad is a member of the Cucurbitaceae plant family which has been used in traditional medicine for the treatment of lung diseases such as asthma and bronchitis. Aim of the studyThe study was conducted to investigate antiproliferative and immunomodulating effects of C. colocynthis and isolated cucurbitacins on human T lymphocytes and lung epithelial cells in order to evaluate their potential in the treatment of airway diseases. Materials and methodsDifferent concentrations of an ethanolic extract of C. colocynthis fruits and cucurbitacins B (CuB), E (CuE) and E-glucopyranoside (CuE-Glu) were analysed for their cytotoxicity and immunomodulatory potential on Peripheral Blood Mononuclear Cells (PBMCs) of healthy donors and on the epithelial lung cancer cell line A549. Viability and proliferation were tested using WST1 and CFSE assays. Flow cytometric analysis of AnnexinV/PI staining was used to investigate cell death through apoptosis/necrosis. Effects on regulatory mechanisms of T lymphocytes, such as CD69 and CD25 marker activation, cytokine production of the cytokines interleukin 2 (IL2), tumor necrosis factor α (TNFα) and interferon γ (IFNy) were also analysed via flow cytometry. Influences on the activator protein 1 (AP1), nuclear factor of activated T-cells (NFAT) or nuclear factor ‘kappa-light-chain-enhancer’ of activated B-cells (NFκB) pathways were analysed in the Jurkat reporter cell line. Cytokine secretion in A549 cells stimulated with virus-like particles was analysed using the bead-based Legendplex™ assay. ResultsNon-toxic concentrations of C. colocynthis and CuE-Glu showed dose-dependent effects on viability and proliferation in both T lymphocytes and A549 cells. The extracts inhibited lymphocyte activation and suppressed T cell effector functions, which was also shown by lower production of cytokines IL2, TNFα and IFNy. A dose dependent inhibition of the pathways NFκB, NFAT and AP1 in Jurkat cells could be observed. In A549 cells, especially CuE and CuE-Glu showed inhibitory effects on cytokine production following a simulated viral infection. Unglycosylated cucurbitacins were more effective in suppressing the immune function in lymphocytes than glycosylated cucurbitacins, however this activity is limited to cytotoxic concentrations. ConclusionIn our study we could confirm the immunmodulating effect of C. colocynthis and cucurbitacins B, E and E-glucopyranoside in vitro by suppression of different pathways of inflammation and T cell proliferation. Activity in a lung cell model using a virus-like stimulation shows promise for further research regarding cucurbitacins in airway diseases.

TIGIT can inhibit T cell activation via ligation-induced nanoclusters, independent of CD226 co-stimulation

TIGIT is an inhibitory receptor expressed on lymphocytes and can inhibit T cells by preventing CD226 co-stimulation through interactions in cis or through competition of shared ligands. Whether TIGIT directly delivers cell-intrinsic inhibitory signals in T cells remains unclear. Here we show, by analysing lymphocytes from matched human tumour and peripheral blood samples, that TIGIT and CD226 co-expression is rare on tumour-infiltrating lymphocytes. Using super-resolution microscopy and other techniques, we demonstrate that ligation with CD155 causes TIGIT to reorganise into dense nanoclusters, which coalesce with T cell receptor (TCR)-rich clusters at immune synapses. Functionally, this reduces cytokine secretion in a manner dependent on TIGIT’s intracellular ITT-like signalling motif. Thus, we provide evidence that TIGIT directly inhibits lymphocyte activation, acting independently of CD226, requiring intracellular signalling that is proximal to the TCR. Within the subset of tumours where TIGIT-expressing cells do not commonly co-express CD226, this will likely be the dominant mechanism of action.

Timing of Mesenchymal Stromal Cell Therapy Defines its Immunosuppressive Effects in a Rat Lung Transplantation Model

Cell therapy using mesenchymal stromal cells (MSCs) is being studied for its immunosuppressive effects. In organ transplantation, the amount of MSCs that accumulate in transplanted organs and other organs may differ depending on administration timing, which may impact their immunosuppressive effects. In vitro, adipose-derived mesenchymal stem cells (ADMSCs) suppress lymphocyte activation under cell-to-cell contact conditions. However, in vivo, it is controversial whether ADMSCs are more effective in accumulating in transplanted organs or in secondary lymphoid organs. Herein, we aimed to investigate whether the timing of ADMSC administration affects its immunosuppression ability in a rat lung transplantation model. In the transplantation study, rats were intramuscularly administered half the usual dose of tacrolimus (0.5 mg/kg) every 24 h after lung transplantation. ADMSCs (1 × 106) were administered via the jugular vein before (PreTx) or after (PostTx) transplantation. Cell tracking using quantum dots was performed. ADMSCs accumulated predominantly in the lung and liver; fewer ADMSCs were distributed in the grafted lung in the PreTx group than in the PostTx group. The rejection rate was remarkably low in the ADMSC-administered groups, particularly in the PostTx group. Serum tumor necrosis factor-α (TNF-α), interferon-γ, and interleukin (IL)-6 levels showed a greater tendency to decrease in the PreTx group than in the PostTx group. The proportion of regulatory T cells in the grafted lung 10 days after transplantation was higher in the PostTx group than in the PreTx group. PostTx administration suppresses rejection better than PreTx administration, possibly due to regulatory T cell induction by ADMSCs accumulated in the transplanted lungs, suggesting a mechanism different from that in heart or kidney transplantation that PreTx administration is more effective than PostTx administration. These results could help establish cell therapy using MSCs in lung transplantation.

Tofacitinib enhances interferon-γ-induced expression of major histocompatibility complex class II in macrophages

Tofacitinib is the first selective Janus kinase (JAK) 1/3 inhibitor approved for the treatment of rheumatoid arthritis and has been demonstrated to exhibit its efficacy through suppression of lymphocyte activation. Although macrophages are critically involved in the pathogenesis of rheumatoid arthritis, little is known about the influence of tofacitinib on macrophage activation especially expression of major histocompatibility complex class II (MHC II) and co-stimulatory molecule CD86. In the present study, we examined the effect of tofacitinib on the expression of MHC II and CD86 in RAW264.7 murine macrophages. Interferon (IFN)-γ induces the cell surface expression of MHC II and CD86. The treatment of tofacitinib at 0.5 μM significantly upregulated IFN-γ-induced expression of MHC II, while decreased the expression of CD86. Hence the population of CD86− MHC II+ cells that induced by tofacitinib at 0.5 μM in the presence of IFN-γ were approximately three times larger than that of IFN-γ alone. Consistent with the surface expression, tofacitinib enhanced IFN-γ-induced mRNA expression of MHC II, and contrarily, decreased that of CD86. Similarly, tofacitinib increased the mRNA expression of MHC II transactivator (CIITA), especially CIITA type I, which is a key regulator of MHC II gene transcription. These findings suggested that tofacitinib enhanced IFNγ-induced MHC II expression by transcriptional regulation through induction of CIITA in macrophages and raise the possibility that a novel action of tofacitinib.

IM-2 Possibility of immunotherapy for the glioblastoma patients with O6-methyl-guanine DNA methyltransferase (MGMT) expression or promoter unmethylated

Background: MGMT is a DNA repair protein that removes the cytotoxic O6-methylguanine (O6MG) DNA lesions generated by TMZ; thereby, MGMT expression is mechanistically linked to TMZ resistance. However, thus far, there is no effective treatment for these patients with MGMT promoter unmethylated. Therefore, a new treatment for GBM patients with MGMT expression is urgently needed. To this end, we examined the tumor microenvironment in GBM with or without MGMT expression. Methods: Based on The Cancer Genome Atlas (TCGA) primary GBM cohort, the tumor-infiltrating lymphocytes (TILs) expression level was calculated using the CIBERSORTx algorithms and the single-sample Gene Set Enrichment Analysis (ssGSEA) method. Furthermore, the differential expression gene analysis was conducted and pathway analysis was performed using Ingenuity Pathway Analysis (IPA). The results were validated using the GBM cohort from the Chinese Glioma Genome Atlas (CGGA) database. In addition, TILs were isolated from 13 surgically removed primary GBM tumors in our institution. Their responses to autologous tumors were evaluated by IFNγ ELISA. Results: T cells CD8 score by CIBERSORTx was significantly higher in the MGMT-high tumor. Similarly, ssGSEA scores for activated CD8 T cell, Macrophage, activated B cell, and Type 1 T helper cell were significantly higher in the MGMT-high tumor. Conversely, T cells CD4 naive was significantly higher in the MGMT-low tumor. Consistently, tumor-reactive TILs were detected in the MGMT-high tumor. Pathway analysis showed that Rictor was highly enriched in the MGMT-high tumor and Rictor inhibited lymphocyte activation. Coclusion: In this study, we demonstrated that macrophage was highly activated in the MGMT-high tumors. Thus, CSF-1R inhibitor can be combined with immunotherapy in these MGMT-high tumors to enhance anti-tumor immune responses. In addition, TMZ + mTOR2 inhibitors + PD-1 inhibitors may be effective against the MGMT-L group.

C3 complement inhibition prevents antibody-mediated rejection and prolongs renal allograft survival in sensitized non-human primates

Sensitized kidney transplant recipients experience high rates of antibody-mediated rejection due to the presence of donor-specific antibodies and immunologic memory. Here we show that transient peri-transplant treatment with the central complement component C3 inhibitor Cp40 significantly prolongs median allograft survival in a sensitized nonhuman primate model. Despite donor-specific antibody levels remaining high, fifty percent of Cp40-treated primates maintain normal kidney function beyond the last day of treatment. Interestingly, presence of antibodies of the IgM class associates with reduced median graft survival (8 vs. 40 days; p = 0.02). Cp40 does not alter lymphocyte depletion by rhesus-specific anti-thymocyte globulin, but inhibits lymphocyte activation and proliferation, resulting in reduced antibody-mediated injury and complement deposition. In summary, Cp40 prevents acute antibody-mediated rejection and prolongs graft survival in primates, and inhibits T and B cell activation and proliferation, suggesting an immunomodulatory effect beyond its direct impact on antibody-mediated injury.

Effects of Tocilizumab Therapy on Circulating B Cells and T Helper Cells in Patients With Neuromyelitis Optica Spectrum Disorder.

Tocilizumab, a humanized anti-IL-6 receptor monoclonal antibody, showed its therapeutic efficacy on neuromyelitis optica spectrum disorder (NMOSD). To assess the immunological effects of this drug on B cells, follicular T helper (Tfh) cells, and peripheral T helper (Tph) cells in patients with NMOSD, peripheral B cell and Tfh cell phenotypes were evaluated in 26 patients with NMOSD before and after tocilizumab treatment by nine-color flow cytometry, as well as the expression of costimulatory and co-inhibitory molecules on B cells. Results showed that the frequency of CD27+IgD− switched memory B cells, CD27-IgD- double-negative B cells, and CD27highCD38high antibody-secreting cells was increased in patients with NMOSD. Tocilizumab treatment led to a significant shift of B cells to naïve B cells from memory B cells after 3 months. Three markers on B cells associated with T-cell activation (i.e., CD86 CD69, and HLA-DR) were downregulated after tocilizumab treatment. The frequencies of total Tfh and Tph cells were decreased, whereas that of follicular regulatory T cells tended to increase. Intrinsic increased PD-L1 and PD-L2 expression was characteristic of B cells in patients with NMOSD. Tocilizumab selectively restored PD-L1 on B-cell subsets. These results provided evidence that tocilizumab enhanced B- and T-cell homoeostasis by regulating B-cell differentiation and inhibiting lymphocyte activation in patients with NMOSD.

Intronic SNP - rs9288953 Of Suppressor Molecule Btla Confers Susceptibility To B-Cell Chronic Lymphocytic Leukemia

The contribution of the immune system to the pathogenesis of B-cell chronic lymphocytic leukemia (B-CLL) have been receiving growing attention. The increase of cancer risk in immunodeficient individuals has been documented in population and experimental studies (Gurlich et al 2007; Swann et al 2007, Smyth et al 2006). A new member of co-inhibitory molecules B - and T-lymphocyte attenuator (BTLA) that inhibits lymphocyte activation could influence cancer susceptibility (Watanabe et al 2003). A high expression of BTLA was observed on malignant B cells from chronic lymphocytic leukemia/small lymphocytic leukemia (M'Hidi et al. 2009). As BTLA synthesis depends on the rate of gene transcription and/or translation, polymorphism in the corresponding gene might result in abnormal expression and function.The aim of this studywas to evaluate possible associations between selected on the basis of literature (Fu et al 2009) single nucleotide polymorphisms (SNPs) existing within exons and introns of BTLA gene: rs9288952A>G, rs1844089G>A, rs2705535C>T and 9288953C>T and susceptibility to B-CLL.Genotyping was done using allelic discrimination method with the TaqMan SNP Genotyping Assays in 300 B-CLL patients (pts.) (203 pts. from Department of Hematology, Medical University Lodz, Poland and 97 from Department of Clinical Immunology and Immunotherapy, Medical University of Lublin, Poland (138 female/162 male) and in 417 healthy individuals (168 female/243 male) originating from the same region of Poland.The significant differences in distribution of alleles and genotypes was observed for intronic SNP -rs9288953. The frequency of T allele and T alleles carriers (CT+TT genotypes) were higher in patients than in healthy controls as compare to C allele and CC genotypes (0.458 vs. 0.375, p=0.0016; OR:1.41, 95%CI - 1.13-1.75 and 0.677 vs. 0.606, p=0.0022; OR:1.67, 95%CI- 1.16-1.2.40, respectively). None of other investigated SNPs have shown different frequency of alleles or genotypes in group of patients and controls.The haplotype analysis of rs9288952A>G, rs1844089G>A, rs2705535C>T and 9288953C>T showed that the most common haplotypes rs9288952A>G[A]/rs1844089G>A[G]/rs2705535C>T[C]/ 9288953C>T[C] (named as AGCC) and rs9288952A>G[A]/rs1844089G>A[G]/rs2705535C>T[C]/ 9288953C>T[T] (named as AGCT) which were differentiate only by variants of 9288953C>T SNP were completely contrary associated with disease susceptibility. Haplotype AGCC is associated with decreased risk of B-CLL (OR: 0.72, 95%CI-0.59-0.90 p with Bonferroni correction=0.01), while AGCT with increased risk of disease (OR: 1.42, 95%CI-1.14-1.76 p with Bonferroni correction=0.005)Our data indicated for the first time the possible role of intronic polymorphism 9288953C>T in gene encoding suppressor molecule BTLA in susceptibility to B-CLL. ReferencesFu Z, Li D, Jiang W, Wang L, Zhang J, Xu F, Pang D, Li D. Association of BTLA gene polymorphisms with the risk of malignant breast cancer in Chinese women of Heilongjiang Province. Breast Cancer Res Treat. 2010 Feb;120(1):195-202.Grulich AE, van Leeuwen MT, Falster MO, Vajdic CM. Incidence of cancers in people with HIV/AIDS compared with immunosuppressed transplant recipients: a meta-analysis. Lancet. 2007 Jul 7;370(9581):59-67.M'Hidi H, Thibult ML, Chetaille B, Rey F, Bouadallah R, Nicollas R, Olive D, Xerri L. High expression of the inhibitory receptor BTLA in T-follicular helper cells and in B-cell small lymphocytic lymphoma/chronic lymphocytic leukemia.Am J Clin Pathol. 2009 Oct;132(4):589-96.Smyth MJ, Dunn GP, Schreiber RD. Cancer immunosurveillance and immunoediting: the roles of immunity in suppressing tumor development and shaping tumor immunogenicity. Adv Immunol. 2006;90:1-50.Swann JB, Smyth MJ. Immune surveillance of tumors. J Clin Invest. 2007 May;117(5):1137-46.Watanabe N, Gavrieli M, Sedy JR, Yang J, Fallarino F, Loftin SK, Hurchla MA, Zimmerman N, Sim J, Zang X, Murphy TL, Russell JH, Allison JP, Murphy KM. BTLA is a lymphocyte inhibitory receptor with similarities to CTLA-4 and PD-1.Nat Immunol. 2003 Jul;4(7):670-9. Disclosures:No relevant conflicts of interest to declare.

THE EFFECT OF CIPLUKAN EXTRACT (Physalis angulata L.) AS ANTIPSORIATIC AND TO LYMPHOCYTES COUNT OF SKIN TISSUE IN PSORIASIS MICE MODEL

ABSTRACT
 Psoriasis is a chronic skin disease in form of papule-shaped lesion and erythematous plaques with thick white scales. The pathogenesis of psoriasis involves IL-23/Th-17 cytokine pathway that contributes the activation of T-lymphocytes and proinflammatory cytokines. Treatment of psoriasis using methotrexate has inhibitory effect of the synthesis of nucleic acid towards T-lymphocytes and keratinocytes. Ciplukan (Physalis angulata L.) has anti-inflammatory potential effect which contains steroid, flavonoid, alkaloid, and physalin that may inhibit lymphocyte activation and proinflammatory cytokine production. The study is used the method of experimental study with post test only with control group design. Thirty five female mices were divided into 7 groups. The parameters of this study is anti-psoriatic (PASI and Baker’s score) and lymphocytes count in psoriasis mice model. The results of Kruskal-Wallis, PASI and Baker’s score showed that p=0,001 (p<0,05) and the result of lymphocytes count using One Way ANOVA showed that p=0,001 (p<0,05). The 800 mg/kgBW dose of ciplukan extract showed the largest decrease on PASI score and lymphocytes count, and the 1200 mg/kgBW dose one showed the largest decrease on the Baker’s score. The present of the 800 mg/kgBW dose of ciplukan extract gives the most optimal effect in reducing PASI score and skin tissue lymphocytes count in psoriasis mice model that were not significantly different with the treatment control group, while 1200 mg/kgBW dose one gives the most optimal effect in reducing Baker’s score that were significantly different with the treatment control group.
 
 Keywords: Ciplukan extract, lymphocytes, methotrexate, Physalis angulata L

Pectin-like polysaccharide extracted from the leaves of Conocarpus erectus Linnaeus promotes antioxidant, immunomodulatory and prebiotic effects

Pectins are complex heteropolysaccharides made up of a linear main chain of repeated units of galacturonic acid that can promote different biological activities. This work aimed to isolate and elucidate the chemical structure of a polysaccharide similar to pectin, obtained from C. erectus leaves. Furthermore, we evaluate the antioxidant and immunomodulatory potential promoted by this macromolecule. The physical-chemical analyzes showed that the pectin obtained showed low degree of esterification and low molecular weight. In addition, it presented in its structure galacturonic acid, glucose, xylose, rhamnose and arabinose. In antioxidant assays in vitro the pectin expressed high activity for the DPPH and ABTS methods. In addition, the pectin obtained was able to promote the growth of probiotic microorganisms in vitro. Immunological tests have shown that pectin was able to stimulate immune cells through the oxidative stress mechanism, promoting lymphocyte proliferation and activation TCD4+ and inhibit lymphocyte activation TCD8+ and stimulate its effector mechanisms through the production of cytokines and nitric oxide, mainly producing a pro-inflammatory immune response, without causing damage to cells. These results highlight the potential use of pectin extracted from C. erectus leaves as an antioxidant, prebiotic and immunomodulatory agent.

Suppressor of cytokine signaling-1 mimetic peptides attenuate lymphocyte activation in the MRL/lpr mouse autoimmune model

Autoimmune diseases are driven largely by a pathogenic cytokine milieu produced by aberrantly activated lymphocytes. Many cytokines, including interferon gamma (IFN-γ), utilize the JAK/STAT pathway for signal propagation. Suppressor of Cytokine Signaling-1 (SOCS1) is an inducible, intracellular protein that regulates IFN-γ signaling by dampening JAK/STAT signaling. Using Fas deficient, MRL/MpJ-Faslpr/J (MRL/lpr) mice, which develop lupus-like disease spontaneously, we tested the hypothesis that a peptide mimic of the SOCS1 kinase inhibitory region (SOCS1-KIR) would inhibit lymphocyte activation and modulate lupus-associated pathologies. Consistent with in vitro studies, SOCS1-KIR intraperitoneal administration reduced the frequency, activation, and cytokine production of memory CD8+ and CD4+ T lymphocytes within the peripheral blood, spleen, and lymph nodes. In addition, SOCS1-KIR administration reduced lymphadenopathy, severity of skin lesions, autoantibody production, and modestly reduced kidney pathology. On a cellular level, peritoneal SOCS1-KIR administration enhanced Foxp3 expression in total splenic and follicular regulatory T cells, reduced the effector memory/naïve T lymphocyte ratio for both CD4+ and CD8+ cells, and reduced the frequency of GL7+ germinal center enriched B cells. Together, these data show that SOCS1-KIR treatment reduced auto-reactive lymphocyte effector functions and suggest that therapeutic targeting of the SOCS1 pathway through peptide administration may have efficacy in mitigating autoimmune pathologies.

Thymosin Alpha 1 Mitigates Cytokine Storm in Blood Cells From Coronavirus Disease 2019 Patients.

BackgroundCoronavirus disease 2019 (COVID-19) is characterized by immune-mediated lung injury and complex alterations of the immune system, such as lymphopenia and cytokine storm, that have been associated with adverse outcomes underlining a fundamental role of host response in severe acute respiratory syndrome coronavirus 2 infection and the pathogenesis of the disease. Thymosin alpha 1 (Tα1) is one of the molecules used in the management of COVID-19, because it is known to restore the homeostasis of the immune system during infections and cancer. MethodsIn this study, we captured the interconnected biological processes regulated by Tα1 in CD8+ T cells under inflammatory conditions. ResultsGenes associated with cytokine signaling and production were upregulated in blood cells from patients with COVID-19, and the ex vivo treatment with Tα1-mitigated cytokine expression, and inhibited lymphocyte activation in a CD8+ T-cell subset specifically. ConclusionThese data suggest the potential role of Tα1 in modulating the immune response homeostasis and the cytokine storm in vivo.

FoxP3, CTLA-4, and IDO in Canine Melanocytic Tumors.

Despite promising immunotherapy strategies in human melanoma, there are few studies on the immune environment of canine melanocytic tumors. In humans, the activation of immunosuppressive cell subpopulations, such as regulatory T cells (Tregs) that express forkhead box protein P3 (FoxP3), the engagement of immunosuppressive surface receptors like cytotoxic T lymphocyte antigen (CTLA-4), and the secretion of molecules inhibiting lymphocyte activation, such as indoleamine-pyrrole 2,3-dioxygenase (IDO), are recognized as immunoescape mechanisms that allow tumor growth and progression. The aim of our study was to investigate the expression of these immunosuppression markers in canine melanocytic tumors and to postulate their possible role in melanoma biology and progression. Fifty-five formalin-fixed, paraffin-embedded canine melanocytic tumors (25 oral melanomas; 20 cutaneous melanomas; 10 cutaneous melanocytomas) were selected to investigate the expression of FoxP3, CTLA-4, and IDO by immunohistochemistry and RT-qPCR (real-time quantitative polymerase chain reaction). All of the tested markers showed high gene and protein expression in oral melanomas and were differently expressed in cutaneous melanomas when compared to their benign counterpart. IDO expression was associated with an increased hazard of death both in univariable and multivariable analyses (P < .05). FoxP3 protein expression >6.9 cells/HPF (high-power field) was an independent predictor of death (P < .05). CTLA-4 gene and protein expressions were associated with a worse prognosis, but only in the univariable analysis (P < .05). FoxP3, CTLA-4, and IDO likely play a role in canine melanoma immunoescape. Their expression, if supported by future studies, could represent a prognostic tool in canine melanoma and pave the way to future immunotherapeutic approaches in dogs.

Endocrine Adverse Events of Nivolumab in Non-Small Cell Lung Cancer Patients-Literature Review.

In recent years, we have observed significant progress in cancer treatment associated with the development of immunotherapy. A programmed cell death 1 molecule (PD-1) on the surface of T lymphocytes may be stimulated via a specific PD-ligand 1 (PD-L1), which inhibits lymphocyte activation and leads to apoptosis. Some malignant cells are characterized by high PD-L1 expression. Nivolumab, an anti-PD-1 antibody, blocks the interaction between PD-1 and its ligands and inhibits the signaling pathway by preventing the tumor-derived PD-L1 from blocking T lymphocytes. In patients with non-small cell lung cancer (NSCLC), it is used either in monotherapy or in combination with other drugs. Immunotherapy is associated with the possibility of immune-related adverse effects (irAE) including endocrinopathies (3–23%). Thyroid disorders are the most common, with severity rarely exceeding grade 2. Hypophysitis, adrenal insufficiency and diabetes are possible complications which require immediate treatment. Individuals with autoimmune diseases diagnosed prior to immunotherapy are at risk of its exacerbation. In the management of patients receiving immunotherapy, evaluation of history of autoimmune diseases, awareness and early diagnosis of irAE are crucial and may affect treatment outcomes.

Differential effects of epirubicin and docetaxel on the immune system in patients with breast cancer (BC).

588 Background: Neoadjuvant chemotherapy (NAC) with epirubicin/cyclophosphamid (EC) followed by docetaxel (D) is currently a standard of care therapy in women with early, high-risk breast cancer (BC). New approaches aim to improve the outcome by combining chemo- with immunotherapy. It is therefore of great interest if chemotherapeutics differ in their effect on the immune system and if some substances are superior combination partners than others. Methods: 79 BC patients, who participated in the ABCSG-34 trial, were included. 39 patients were treated with 6 cycles of EC followed by 6 cycles of D and 40 received the reverse sequence (D→EC). Blood was collected before and after 6 cycles. The plasma levels of a variety of immune mediators were determined by multiplex bead array assay. The response to therapy was measured by Residual Cancer Burden (RCB)-score. A score of ≤1.36 was determined as good response. Lymphocyte activation was assessed after stimulation with phytohaemagglutinin (PHA) by flow cytometric analysis of IFNgamma. Additionally, lymphocytes of 6 healthy probands were stimulated with PHA and treated with E or D. The stimulation was quantified by measuring cluster formation after 5 days. Further, a human BC cell line (SK-BR3) was treated with E or D. The induced cell death was determined morphologically as well as by flow cytometry after staining of phosphatidylserine, Sub-G1 DNA and active caspase-3. Results: The treatment of BC patients with 6 cycles of EC resulted in a decrease of lymphocyte stimulation whereas 6 cycles of D had no effect. The plasma levels of most immune mediators decreased significantly after six cycles EC when compared to baseline. Under the influence of D, the effect was much weaker. The changes of Eotaxin and OPG during the first 6 cycles of D correlated with the RCB-score in the reverse group. A decrease in Eotaxin (p = 0.0136) or in OPG (p = 0.0487) correlated with good response. The in vitro lymphocyte stimulation assay showed that E and D have similar inhibitory effects on lymphocytes.The annexin V/PI analysis confirmed that E more often leads to apoptotic cell death in SK-BR3 cells than D (E:53% vs. D:14%). SK-BR3 cells formed more often polyploid cells when treated with D. This suggests that D induces a regulated form of necrosis whereas E apoptosis. Conclusions: This study is the first to compare the immunomodulatory effect of E and D in BC patients. E inhibits lymphocyte activation in vitro and in vivo and suppresses many soluble immune mediators. This suggests that it is not suited for combination with immunotherapies. D showed a much weaker effect.

Immunomodulatory effects of some Namibian plants traditionally used for treating inflammatory diseases

Ethnopharmacological relevanceAcanthosicyos naudininus, Gomphocarpus fruticosus, and Cryptolepis decidua are, according to the knowledge of traditional healers, used in Namibia to treat inflammatory disorders such as pain, fever and skin rashes.Aim of the study: The present study was conducted to evaluate the immunomodulatory effects and the possible underlying mechanisms of action of the plant extracts on peripheral blood mononuclear cells (PBMCs) such as T-lymphocytes. Materials and methodsMethanolic and EtOAc extracts of A. naudinianus, G. fruticosus and C. decidua were analysed for their immunomodulatory potential. PBMCs were isolated from the blood of healthy donors and incubated with the plant extracts at concentrations 100, 30, 10, 3, 1 and 0.3 μg/mL. Effects on proliferation and viability of activated human lymphocytes were assessed in comparison to ciclosporin A by flow cytometry using carboxyfluorescein succinimidyl ester (CFSE) and WST-1 assay. Flow cytometry by annexin V/propidium iodide (PI) staining was performed to investigate the necrotic/apoptotic effect of the plant extracts on mitogen-activated human lymphocytes. In addition, analysis of the influence of plant extracts on the regulatory mechanisms of T-lymphocytes was performed using activation marker and cytokine production assays. An HPLC-PDA-ELSD-ESIMS profile was recorded for each of the extracts. ResultsT-lymphocyte proliferation was inhibited in a dose-dependent manner by the extracts of A. naudinianus, G. fruticosus, and C. decidua in concentrations not causing apoptosis or necrosis. This effect was mediated by inhibition of lymphocyte activation, specifically the suppression of CD25 and CD69 surface receptor expression. Moreover, the extracts suppressed effector functions, as indicated by reduced production of IFN-γ and IL-2. Based on the HPLC profile, possible responsible compound classes could be identified for the extracts of A. naudinianus (cucurbitacins) and C. decidua (indole alkaloids), but not for G. fruticosus. ConclusionsThe data show that the extracts of A. naudinianus, G. fruticosus and C. decidua have in vitro immunomodulatory activity and they interfere with the function of immunocompetent cells, suggesting an anti-inflammatory mode-of-action. The present chemical determination and pattern recognition results explain the therapeutic potency. However, further studies to investigate the therapeutic potential of the plants in inflammatory disorders should be done.

Mycophenolate mofetil, azathioprine and tacrolimus: mechanisms in rheumatology.

The introduction of biologic DMARDs into rheumatology has resulted in a substantial reduction of the burden of many rheumatic diseases. In the slipstream of the success achieved with these biologic DMARDs, some conventional immunosuppressive drugs have also found use in new indications. Notably, mycophenolate mofetil, azathioprine and tacrolimus have made their way from solid organ transplantation drugs to become useful assets in rheumatology practice. Mycophenolate mofetil and azathioprine inhibit the purine pathway and subsequently diminish cell proliferation. Both drugs have a pivotal role in the treatment of various rheumatic diseases, including lupus nephritis. Tacrolimus inhibits lymphocyte activation by inhibiting the calcineurin pathway. Mycophenolate mofetil and tacrolimus are, among other indications, increasingly being recognized as useful drugs in the treatment of interstitial lung disease in systemic rheumatic diseases and skin fibrosis in systemic sclerosis. A broad array of trials with mycophenolate mofetil, azathioprine and/or tacrolimus are ongoing within the field of rheumatology that might provide further novel avenues for the use of these drugs. In this Review, we discuss the historical perspective, pharmacodynamics, clinical indications and novel avenues for mycophenolate mofetil, azathioprine and tacrolimus in rheumatology.

Integrin and PD-1 Ligand Expression on Circulating Extracellular Vesicles in Systemic Inflammatory Response Syndrome and Sepsis.

Extracellular vesicles (EVs) in the plasma mediate important intercellular communications in the pathogenesis of cancer and inflammatory diseases. EVs express integrins that regulate target specificities and programmed cell death ligand 1 and 2 (PD-L1 and 2) that suppress lymphocyte activation. However, the roles of these molecules on EVs in systemic inflammatory response syndrome (SIRS) and sepsis remain little understood. This study aimed to investigate how the EV expression of integrins and PD-1 ligands might differ in SIRS and sepsis, compared with healthy controls, and to correlate their expression with the clinical parameters reflecting pathogenesis. Twenty-seven SIRS patients without sepsis, 27 sepsis patients, and 18 healthy volunteers were included. EVs were isolated from plasma samples. The expression of three major integrins (β1, β2, β3 integrins) and PD-L1 and 2 were measured. The EV expression of β2 integrin and PD-L2 was significantly increased in sepsis patients compared with healthy controls. EV expression of PD-L1 was not elevated in sepsis and SIRS; however, circulating soluble PD-L1 levels were significantly higher in sepsis. Furthermore, EV expression of β2 integrin in sepsis patients correlated with hypotension and reduced kidney function. In addition, soluble PD-L1 levels correlated with sepsis severity, impaired kidney function, and impaired central nervous system function. These results suggest the potential involvements of the EV β2 integrin, as well as EV PD-L2 and soluble PD-L1, in the septic pathogenesis that occurs with the systemic immune activation leading to multiple organ dysfunctions.

Immunomodulatory Properties of Mesenchymal Stromal Cells: Still Unresolved "Yin and Yang".

Mesenchymal stromal cells (MSC) are mesodermal elements characterized by the ability to differentiate into several types of cells present mainly in connective tissues. They play a key function in tissue homeostasis and repair. Furthermore, they exert a strong effect on both innate and adaptive immune response. The main current of thought considers MSC as strong inhibitors of the immune system. Indeed, the first description of MSC immunomodulation pointed out their inability to induce alloimmune responses and their veto effects on mixed lymphocyte reactions. This inhibition appears to be mediated both by direct MSC interaction with immune cells and by soluble factors. Unfortunately, evidence to support this notion comes almost exclusively from in vitro experiments. In complex experimental systems, it has been shown that MSC can exert immunosuppressive effects also in vivo, either in murine models or in transplanted patients to avoid the graft versus host disease. However, it is still debated how the small number of administered MSC can regulate efficiently a large number of host effector lymphocytes. In addition, some reports in the literature indicate that MSC can trigger rather than inhibit lymphocyte activation when a very low number of MSC are co-cultured with lymphocytes. This would imply that the ratio between the number of MSC and immune cells is a key point to forecast whether MSC will inhibit or activate the immune system. Herein, we discuss the conflicting results reported on the immunomodulatory effects of MSC to define which features are relevant to understand their behavior and cross-talk with immune cells.