Tumor-associated macrophage (TAM)-secreted CCL22 confers cisplatin resistance of esophageal squamous cell carcinoma (ESCC) cells via regulating the activity of diacylglycerol kinase α (DGKα)/NOX4 axis.

Tumor-associated macrophages (TAMs) are often associated with chemoresistance and resultant poor clinical outcome in solid tumors. Here, we demonstrated that TAMs-released chemokine-C-C motif chemokine 22 (CCL22) in esophageal squamous cell carcinoma (ESCC) stroma was tightly correlated with the chemoresistance of ESCC patients. TAMs-secreted CCL22 was able to block the growth inhibitory and apoptosis-promoting effects of cisplatin on ESCC cells. Mechanistically, CCL22 stimulated intratumoral diacylglycerol kinase α (DGKα) to produce phosphatidic acid (PA), which suppressed the activity of NADPH oxidase 4 (NOX4) and then blocked the overproduction of intratumoral reactive species oxygen (ROS) induced by cisplatin. CCL22 activated DGKα/nuclear factor-κB (NF-κB) axis to upregulate the level of several members of ATP binding cassette (ABC) transporter superfamily, including ABC sub-family G member 4 (ABCG4), ABC sub-family A member 3 (ABCA3), and ABC sub-family A member 5 (ABCA5), to lower the intratumoral concentration of cisplatin. Consequently, these processes induced the cisplatin resistance in ESCC cells. In xenografted models, targeting DGKα with 5'-cholesterol-conjugated small-interfering (si) RNA enhanced the chemosensitivity of cisplatin in ESCC treatment, especially in the context of TAMs. Our data establish the correlation between the TAMs-induced intratumoral metabolic product/ROS axis and chemotherapy efficacy in ESCC treatment and reveal relevant molecular mechanisms.

Generation of a human induced pluripotent stem cell line overexpressing CCL22 with islet cells differentiation potential.

CCL22 is a macrophage-derived immunosuppressive chemokine that recruits regulatory T cells through the CCL22:CCR4 axis, playing an important role in homeostatic and inflammatory responses. A CCL22-overexpressing human induced pluripotent stem cell line (CNNDi001-A-2) was generated by lentiviral transduction to further study the function of CCL22. The cell line was confirmed to have normal proliferation and pluripotency and could be further differentiated into islet cells for cell replacement therapy in diabetes.

Downstream STING pathways IRF3 and NF-κB differentially regulate CCL22 in response to cytosolic dsDNA.

Double-stranded DNA (dsDNA) in the cytoplasm of eukaryotic cells is abnormal and typically indicates the presence of pathogens or mislocalized self-DNA. Multiple sensors detect cytosolic dsDNA and trigger robust immune responses via activation of type I interferons. Several cancer immunotherapy treatments also activate cytosolic nucleic acid sensing pathways, including oncolytic viruses, nucleic acid-based cancer vaccines, and pharmacological agonists. We report here that cytosolic dsDNA introduced into malignant cells can robustly upregulate expression of CCL22, a chemokine responsible for the recruitment of regulatory T cells (Tregs). Tregs in the tumor microenvironment are thought to repress anti-tumor immune responses and contribute to tumor immune evasion. Surprisingly, we found that CCL22 upregulation by dsDNA was mediated primarily by interferon regulatory factor 3 (IRF3), a key transcription factor that activates type I interferons. This finding was unexpected given previous reports that type I interferon alpha (IFN-α) inhibits CCL22 and that IRF3 is associated with strong anti-tumor immune responses, not Treg recruitment. We also found that CCL22 upregulation by dsDNA occurred concurrently with type I interferon beta (IFN-ß) upregulation. IRF3 is one of two transcription factors downstream of the STimulator of INterferon Genes (STING), a hub adaptor protein through which multiple dsDNA sensors transmit their signals. The other transcription factor downstream of STING, NF-κB, has been reported to regulate CCL22 expression in other contexts, and NF-κB has also been associated with multiple pro-tumor functions, including Treg recruitment. However, we found that NF-κB in the context of activation by cytosolic dsDNA contributed minimally to CCL22 upregulation compared with IRF3. Lastly, we observed that two strains of the same cell line differed profoundly in their capacity to upregulate CCL22 and IFN-ß in response to dsDNA, despite apparent STING activation in both cell lines. This finding suggests that during tumor evolution, cells can acquire, or lose, the ability to upregulate CCL22. This study adds to our understanding of factors that may modulate immune activation in response to cytosolic DNA and has implications for immunotherapy strategies that activate DNA sensing pathways in cancer cells.

Macrophage-Derived Chemokine MDC/CCL22: An Ambiguous Finding in COVID-19.

Macrophage-derived chemokine (MDC/CCL22) is a chemokine of the C-C subfamily. It is involved in T-cellular maturation and migration. Our previous research shows that plasma CCL22/MDC tends to show a statistically significant depletion of concentrations in acute patients and convalescents when compared to healthy donors. In the current work, we investigate existing views on MDC/CCL22 dynamics in association with various pathologies, including respiratory diseases and, specifically, COVID-19. Additionally, we present our explanations for the observed decrease in MDC/CCL22 concentrations in COVID-19. The first hypothesis we provide implies that viral products bind to MDC/CCL22 and block its activity. Another explanation for this phenomenon is based on dendritic cells population and the inhibition of their function.

[Regulation of Baicalin on Growth of Extranodal NK/T Cell Lymphoma Cells through FOXO3/CCL22 Signaling Pathway].

OBJECTIVE: To investigate the effect of baicalin on the growth of extranodal NK/T cell lymphoma (ENKTCL) cells and its related mechanism. METHODS: Normal NK cells and human ENKTCL cells lines SNK-6 and YTS were cultured, then SNK-6 and YTS cells were treated with 5, 10, 20 µmol/L baicalin and set control. Cell proliferation and apoptosis was detected by Edu method and FCM method, respectively, and expressions of BCL-2, Bax, FOXO3 and CCL22 proteins were detected by Western blot. Interference plasmids were designed and synthesized. FOXO3 siRNA interference plasmids and CCL22 pcDNA overexpression plasmids were transfected with PEI transfection reagent. Furthermore, animal models were established for validation. RESULTS: In control group and 5, 10, 20 µmol/L baicalin group, the proliferation rate of SNK-6 cells was (56.17±2.96)%, (51.92±4.63)%, (36.42±1.58)%, and (14.60±2.81)%, respectively, while that of YTS cells was (58.85±2.98)%, (51.38±1.32)%, (34.75±1.09)%, and (15.45±1.10)%, respectively. In control group and 5, 10, 20 µmol/L baicalin group, the apoptosis rate of SNK-6 cells was (5.93±0.74)%, (11.78±0.34)%, (28.46±0.44)%, and (32.40±0.37)%, respectively, while that of YTS cells was (7.93±0.69)%, (16.29±1.35)%, (33.91±1.56)%, and (36.27±1.06)%, respectively. Compared with control group, the expression of BCL-2 protein both in SNK-6 and YTS cells decreased significantly (P<0.001), and the expression of Bax protein increased in SNK-6 cells only when the concentration of baicalin was 20 µmol/L (P<0.001), while that in YTS cells increased in all three concentrations(5, 10, 20 µmol/L) of baicalin (P<0.001). The expression of FOXO3 protein decreased while CCL22 protein increased in ENKTCL cell lines compared with human NK cells (P<0.001), but the expression of FOXO3 protein increased (P<0.01) and CCL22 protein decreased after baicalin treatment (P<0.001). Animal experiments showed that baicalin treatment could inhibit tumor growth. The expression of CCL22 protein in ENKTCL tissue of nude mice treated with baicalin decreased compared with control group (P<0.01), while the FOXO3 protein increased (P<0.05). In addition, FOXO3 silencing resulted in the decrease of FOXO3 protein expression and increase of CCL22 protein expression (P<0.01, P<0.001). CONCLUSION: Baicalin can inhibit proliferation and promote apoptosis of ENKTCL cell lines SNK-6 and YTS, up-regulate the expression of Bax protein, down-regulate the expression of BCL-2 protein, and down-regulate the expression of CCL22 protein mediated by FOXO3. Animal experiment shown that the baicalin can inhibit tumor growth. Baicalin can inhibit the growth and induce apoptosis of ENKTCL cells through FOXO3/CCL22 signaling pathway.

CCL17 and CCL22 chemokines are upregulated in human obesity and play a role in vascular dysfunction.

Background/Aims: Chemokines are known to play critical roles mediating inflammation in many pathophysiological processes. The aim of this study was to investigate the role of chemokine receptor CCR4 and its ligands CCL17 and CCL22 in human morbid obesity. Methods: Circulating levels of CCL17 and CCL22 were measured in 60 morbidly obese patients (mean age, 45 ± 1 years; body mass index/BMI, 44 ± 1 kg/m2) who had undergone bariatric bypass surgery, and 20 control subjects. Paired subcutaneous (SCAT) and visceral adipose tissue (VCAT) from patients were analysed to measure expression of CCR4 and its ligands by RT-PCR, western blot and immunohistochemical analysis. The effects of CCR4 neutralization ex vivo on leukocyte-endothelial cells were also evaluated. Results: Compared with controls, morbidly obese patients presented higher circulating levels of CCL17 (p=0.029) and CCL22 (p<0.001) and this increase was positively correlated with BMI (p=0.013 and p=0.0016), and HOMA-IR Index (p=0.042 and p< 0.001). Upregulation of CCR4, CCL17 and CCL22 expression was detected in VCAT in comparison with SCAT (p<0.05). Using the parallel-plate flow chamber model, blockade of endothelial CCR4 function with the neutralizing antibody anti-CCR4 in morbidly obese patients significantly reduced leucocyte adhesiveness to dysfunctional endothelium, a key event in atherogenesis. Additionally, CCL17 and CCL22 increased activation of the ERK1/2 mitogen-activated protein kinase signalling pathway in human aortic endothelial cells, which was significantly reduced by CCR4 inhibition (p=0.016 and p<0.05). Conclusion: Based on these findings, pharmacological modulation of the CCR4 axis could represent a new therapeutic approach to prevent adipose tissue dysfunction in obesity.

Fulvic Acid Attenuates Atopic Dermatitis by Downregulating CCL17/22.

The main pathogenic factor in atopic dermatitis (AD) is Th2 inflammation, and levels of serum CCL17 and CCL22 are related to severity in AD patients. Fulvic acid (FA) is a kind of natural humic acid with anti-inflammatory, antibacterial, and immunomodulatory effects. Our experiments demonstrated the therapeutic effect of FA on AD mice and revealed some potential mechanisms. FA was shown to reduce TARC/CCL17 and MDC/CCL22 expression in HaCaT cells stimulated by TNF-α and IFN-γ. The inhibitors showed that FA inhibits CCL17 and CCL22 production by deactivating the p38 MAPK and JNK pathways. After 2,4-dinitrochlorobenzene (DNCB) induction in mice with atopic dermatitis, FA effectively reduced the symptoms and serum levels of CCL17 and CCL22. In conclusion, topical FA attenuated AD via downregulation of CCL17 and CCL22, via inhibition of P38 MAPK and JNK phosphorylation, and FA is a potential therapeutic agent for AD.

Increase of the T-reg-recruiting chemokine CCL22 expression in a progressive course of cervical dysplasia.

PURPOSE: An increasing infiltration of FoxP3-positive T-regs is associated with a higher grade of cervical intraepithelial neoplasia. The T-reg-recruiting chemokine CCL22 is expressed in various tumour entities. Aim of our study was to investigate the role of CCL22 in the progression and regression of cervical intraepithelial neoplasias, especially in patients with intermediate cervical intraepithelial neoplasias (CIN II). Furthermore, our aim was to characterize the CCL22-producing cells and explore the role of innate immunity in the process of cells recruitment. METHODS: CCL22 expression was analyzed immunohistochemically in 169 patient samples. The immunoreactive score as well as the median numbers of positive cells were calculated in each slide and correlated with the histological CIN grade and FoxP3 expression. Additionally, CD68/CCL22 as well as CD68/PPARγ and CD68/FoxP3 expression were examined by double immunofluorescence. Statistical analysis was performed by SPSS 26. RESULTS: A significantly higher expression of epithelial CCL22 in CIN II with progression in comparison to CIN II with regression (p = 0.006) could be detected. CCL22 was correlated with FoxP3 (Spearman's Rho: 0.308; p < 0.01). In 88%, CCL22-positive cells were positive for CD68, and 71% of CD68-positive macrophages expressed PPARγ. Colocalization of CD68 and FoxP3 was detected in 12%. CONCLUSION: We could demonstrate that increased expression of CCL22, mainly produced by macrophages, correlates with elevated potential of malignancy. CCL22 expression could act as a predictor for regression and progression in cervical intraepithelial neoplasia, and it may help in the decision process regarding surgical treatment versus watchful waiting strategy in order to prevent conisation-associated risks. Furthermore, our findings support the potential of CCL22-producing cells as a target for immune therapy in cervical cancer patients.

Correlations of Myeloperoxidase (MPO), Adenosine deaminase (ADA), C-C motif chemokine 22 (CCL22), Tumour necrosis factor alpha (TNFα) and Interleukin-6 (IL-6) mRNA expression in the nasopharyngeal specimens with the diagnosis and severity of SARS-CoV-2 infections.

Cytokine dynamics in patients with coronavirus disease 2019 (COVID-19) have been studied in blood but seldomly in respiratory specimens. We studied different cell markers and cytokines in fresh nasopharyngeal swab specimens for the diagnosis and for stratifying the severity of COVID-19. This was a retrospective case-control study comparing Myeloperoxidase (MPO), Adenosine deaminase (ADA), C-C motif chemokine ligand 22 (CCL22), Tumour necrosis factor alpha (TNFα) and Interleukin-6 (IL-6) mRNA expression in 490 (327 patients and 163 control) nasopharyngeal specimens from 317 (154 COVID-19 and 163 control) hospitalized patients. Of the 154 COVID-19 cases, 46 died. Both total and normalized MPO, ADA, CCL22, TNFα, and IL-6 mRNA expression levels were significantly higher in the nasopharyngeal specimens of infected patients when compared with controls, with ADA showing better performance (OR 5.703, 95% CI 3.424-9.500, p < 0.001). Receiver operating characteristics (ROC) curve showed that the cut-off value of normalized ADA mRNA level at 2.37 × 10-3 had a sensitivity of 81.8% and specificity of 83.4%. While patients with severe COVID-19 had more respiratory symptoms, and elevated lactate dehydrogenase, multivariate analysis showed that severe COVID-19 patients had lower CCL22 mRNA (OR 0.211, 95% CI 0.060-0.746, p = 0.016) in nasopharyngeal specimens, while lymphocyte count, C-reactive protein, and viral load in nasopharyngeal specimens did not correlate with disease severity. In summary, ADA appears to be a better biomarker to differentiate between infected and uninfected patients, while CCL22 has the potential in stratifying the severity of COVID-19.

Regulation of Baicalin on Growth of Extranodal NK/T Cell Lymphoma Cells through FOXO3/CCL22 Signaling Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of baicalin on the growth of extranodal NK/T cell lymphoma (ENKTCL) cells and its related mechanism.@*METHODS@#Normal NK cells and human ENKTCL cells lines SNK-6 and YTS were cultured, then SNK-6 and YTS cells were treated with 5, 10, 20 μmol/L baicalin and set control. Cell proliferation and apoptosis was detected by Edu method and FCM method, respectively, and expressions of BCL-2, Bax, FOXO3 and CCL22 proteins were detected by Western blot. Interference plasmids were designed and synthesized. FOXO3 siRNA interference plasmids and CCL22 pcDNA overexpression plasmids were transfected with PEI transfection reagent. Furthermore, animal models were established for validation.@*RESULTS@#In control group and 5, 10, 20 μmol/L baicalin group, the proliferation rate of SNK-6 cells was (56.17±2.96)%, (51.92±4.63)%, (36.42±1.58)%, and (14.60±2.81)%, respectively, while that of YTS cells was (58.85±2.98)%, (51.38±1.32)%, (34.75±1.09)%, and (15.45±1.10)%, respectively. In control group and 5, 10, 20 μmol/L baicalin group, the apoptosis rate of SNK-6 cells was (5.93±0.74)%, (11.78±0.34)%, (28.46±0.44)%, and (32.40±0.37)%, respectively, while that of YTS cells was (7.93±0.69)%, (16.29±1.35)%, (33.91±1.56)%, and (36.27±1.06)%, respectively. Compared with control group, the expression of BCL-2 protein both in SNK-6 and YTS cells decreased significantly (P<0.001), and the expression of Bax protein increased in SNK-6 cells only when the concentration of baicalin was 20 μmol/L (P<0.001), while that in YTS cells increased in all three concentrations(5, 10, 20 μmol/L) of baicalin (P<0.001). The expression of FOXO3 protein decreased while CCL22 protein increased in ENKTCL cell lines compared with human NK cells (P<0.001), but the expression of FOXO3 protein increased (P<0.01) and CCL22 protein decreased after baicalin treatment (P<0.001). Animal experiments showed that baicalin treatment could inhibit tumor growth. The expression of CCL22 protein in ENKTCL tissue of nude mice treated with baicalin decreased compared with control group (P<0.01), while the FOXO3 protein increased (P<0.05). In addition, FOXO3 silencing resulted in the decrease of FOXO3 protein expression and increase of CCL22 protein expression (P<0.01, P<0.001).@*CONCLUSION@#Baicalin can inhibit proliferation and promote apoptosis of ENKTCL cell lines SNK-6 and YTS, up-regulate the expression of Bax protein, down-regulate the expression of BCL-2 protein, and down-regulate the expression of CCL22 protein mediated by FOXO3. Animal experiment shown that the baicalin can inhibit tumor growth. Baicalin can inhibit the growth and induce apoptosis of ENKTCL cells through FOXO3/CCL22 signaling pathway.

CCL22 and CCL26 are potential biomarkers for predicting distant metastasis in thyroid carcinoma.

OBJECTIVES: Chemokines have been suggested to play significant roles in the progression of malignant cancers. This study aimed to identify the chemokines related to malignant progression in thyroid carcinoma. METHODS: The mRNA expression levels of 52 chemokines were compared between differentiated thyroid cancer (DTC) samples and normal thyroid tissues from The Cancer Genome Atlas database; survival analysis was then performed on the basis of differentially expressed chemokines. A retrospective study was conducted on the level of differentially expressed chemokines in 76 DTC patients. Functional pathway analysis was performed to explore chemokine-related regulatory mechanisms. RESULTS: We identified 20 chemokines with differentially expressed mRNA levels through publicly available data. High levels of CCL22 and CCL26 were found to be related with metastasis in clinical DTC samples. High levels of CCL22 were found to be significantly related to poor prognosis in DTC patients. Pathway analyses revealed that cytokines might affect cancer progression through cytokine-cytokine receptor and cytokine-interleukin interactions. CONCLUSIONS: CCL22 and CCL26 could serve as prognostic biomarkers in thyroid carcinoma.

Spatial Transcriptomics Analysis Reveals that CCL17 and CCL22 are Robust Indicators of a Suppressive Immune Environment in Angioimmunoblastic T Cell Lymphoma (AITL).

BACKGROUND: T cell lymphoma is a complex and highly aggressive clinicopathological entity with a poor outcome. The angioimmunoblastic T-cell lymphoma (AITL) tumor immune microenvironment is poorly investigated. METHODS: Here, to the best of our knowledge, spatial transcriptomics was applied for the first time to study AITL. RESULTS: Using this method, we observed that AITL was surrounded by cells bearing immune-suppressive markers. CCL17 and CCL22, the dominant ligands for CCR4, were up-regulated, while the expression of natural killer (NK) cell and CD8+ cytotoxic T lymphocyte (CTL) markers decreased. Colocalization of Treg cells with the CD4+ TFH-GC region was also deduced from the bioinformatic analysis. The results obtained with spatial transcriptomics confirm that AITL has a suppressive immune environment. Chemotherapy based on the CHOP regimen (cyclophosphamide, doxorubicin, vincristine plus prednisone) induced complete remission (CR) in this AITL patient. However, the duration of remission (DoR) remains a concern. CONCLUSIONS: This study demonstrates that AITL has an immune suppressive environment and suggests that anti-CCR4 therapy could be a promising treatment for this lethal disease.

Endogenous Adenosine 5'-Monophosphate, But Not Acetylcholine or Histamine, is Associated with Asthma Control, Quality of Life, and Exacerbations.

OBJECTIVE: Endogenous adenosine 5'-monophosphate (AMP), acetylcholine (ACh), and histamine (HA) are known to be important in bronchial contraction, but their clinical relevance to asthma is poorly understood. We aimed to quantify endogenous AMP, ACh, and HA in induced sputum samples and explore their relationships with asthma control and exacerbations. METHODS: 20 healthy subjects and 112 asthmatics underwent clinical assessment, sputum induction, and blood sampling. The level of asthma control was determined by the asthma control test (ACT) questionnaire. Asthma exacerbation was evaluated according to the criteria of the American Thoracic Society/European Respiratory Society. Levels of AMP, ACh, and HA in sputum were measured by liquid chromatography coupled to tandem mass spectrometry. IL-ß, IL-4, IL-5, IL-6, IL-8, IL-13, IL-17A, TNF-α, IFN-γ, and macrophage-derived chemokine (MDC) were also measured. RESULTS: Compared to healthy controls, asthmatics had higher levels of HA, lower levels of ACh, and similar levels of AMP in induced sputum samples. Compared to controlled asthma (n = 54), uncontrolled asthma (n = 58) showed higher AMP levels (P = 0.002), but similar HA and ACh levels. AMP was negatively correlated with ACT scores (r = - 0.348) and asthma quality of life questionnaire scores (r = - 0.188) and positively correlated with blood monocytes percentage (r = 0.195), sputum MDC (r = 0.214), and IL-6 levels (r = 0.196). Furthermore, AMP was associated with an increased risk of exacerbations in the preceding year. CONCLUSION: Endogenous AMP, but not ACh or HA, was associated with asthma control, quality of life, and exacerbations in the previous year, which indicates that AMP could be a clinically useful biomarker of asthma.

The CC ligand chemokine family members CCL17/CCL22 predict the survival and response to immune checkpoint blockade therapy of patients with head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is considered an immunosuppressive malignancy. Cross-talk between cancer cells and immune cells is modulated in part by CC ligand (CCL) chemokines, having a major effect on tumor progression. However, the predictive value and function of CCL family members in HNSCC have not been elucidated. Here, the predictive value of CCL members in cancer prognosis and Immune checkpoint blockade therapy response was investigated. CCL17 and CCL22 were screened as the key CCL chemokines in HNSCC through co-expression analysis. Further, the correlation between CCL17/CCL22 expression and cancer immune infiltration were evaluated based on TIMER and were validated by a set of scRNA-seq data. Moreover, the expression level of CCL17/CCL22 we evaluated to predict the response to Immune checkpoint blockade therapy in a panel of cancer types by using the TIDE database. Results indicated that CCL17/CCL22 had a high co-expression correlation and had a marginally statistical significance with the overall survival in HNSCC patients (P value = 0.057 and 0.055, respectively). Our findings showed high expression of CCL17/CCL22 was positively correlated with CD4+ T cell infiltration levels in HNSCCs and activate mTORC1 signaling pathway in CD4+ T cells. Further analysis from TIDE showed the high expression of CCL17/CCL22 might predict favorable responses to immune checkpoint blockade therapy in HNSCC patients. These findings provide an insight into the predictive roles of CCL17/CCL22 in HNSCC.

3-Bromo-4,5-dihydroxybenzaldehyde Isolated from Polysiphonia morrowii Suppresses TNF-α/IFN-γ-Stimulated Inflammation and Deterioration of Skin Barrier in HaCaT Keratinocytes.

Polysiphonia morrowii is a well-known red alga that has promising pharmacological characteristics. The current study evaluates the protective effect of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) isolated from P. morrowii on tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated inflammation and skin barrier deterioration in HaCaT keratinocytes. The anti-inflammatory effect of BDB in TNF-α/IFN-γ-stimulated HaCaT keratinocytes is evaluated by investigating nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, inflammatory cytokines, and chemokines. Further, the interaction between BDB and the skin barrier functions in stimulated HaCaT keratinocytes is investigated. The findings of the study reveal that BDB dose-dependently increases cell viability while decreasing intracellular reactive oxygen species (ROS) production. BDB downregulates the expression of inflammatory cytokines, interleukin (IL)-6, -8, -13, IFN-γ, TNF-α, and chemokines, Eotaxin, macrophage-derived chemokine (MDC), regulated on activation, normal T cells expressed and secreted (RANTES), and thymus and activation-regulated chemokine (TARC) by modulating the MAPK and NF-κB signaling pathways in TNF-α/IFN-γ-stimulated HaCaT keratinocytes. Furthermore, BDB increases the production of skin hydration proteins and tight junction proteins in stimulated HaCaT keratinocytes by preserving skin moisturization and tight junction stability. These findings imply that BDB exhibits a protective ability against inflammation and deterioration of skin barrier via suppressing the expression of inflammatory signaling in TNF-α/IFN-γ-stimulated HaCaT keratinocytes.

Identification of the Binding Epitope of an Anti-mouse CCR4 Monoclonal Antibody, C4Mab-1.

C-C chemokine receptor 4 (CCR4) is one of G protein-coupled receptors, and interacts with chemokines, CCL17 and CCL22. CCR4 is expressed on T cells such as helper T type 2 cells, regulatory T cells, and interleukin 17-producing T helper cells. CCR4 is associated with T cells trafficking into the tumor microenvironment, and is associated with tumor progression or metastasis. Therefore, CCR4 may be a potential therapeutic option for T cell malignancies. C4Mab-1 is a novel anti-mouse CCR4 (mCCR4) monoclonal antibody produced by mCCR4 N-terminal peptide immunization. C4Mab-1 is useful for flow cytometric analysis. In this study, we conducted the epitope mapping of C4Mab-1 using enzyme-linked immunosorbent assay (ELISA) and peptide blocking assay. The result of ELISA indicated that Thr7, Asp8, and Gln11 of mCCR4 are the critical amino acids for the C4Mab-1 binding. Furthermore, peptide blocking assay by flow cytometry showed that Thr7, Asp8, and Gln11 of mCCR4 are essential for C4Mab-1 binding to mCCR4-overexpressed Chinese hamster ovary-K1 (CHO/mCCR4) cells, and Val6, Thr9, and Thr10 are involved in the C4Mab-1 binding to CHO/mCCR4 cells. These results indicate that the critical binding epitope of C4Mab-1 includes Thr7, Asp8, and Gln11 of mCCR4.

Tumor-associated macrophage (TAM)-derived CCL22 induces FAK addiction in esophageal squamous cell carcinoma (ESCC).

Tumor cell dependence on activated oncogenes is considered a therapeutic target, but protumorigenic microenvironment-mediated cellular addiction to specific oncogenic signaling molecules remains to be further defined. Here, we showed that tumor-associated macrophages (TAMs) produced an abundance of C-C motif chemokine 22 (CCL22), whose expression in the tumor stroma was positively associated with the level of intratumoral phospho-focal adhesion kinase (pFAK Tyr397), tumor metastasis and reduced patient survival. Functionally, CCL22-stimulated hyperactivation of FAK was correlated with increased malignant progression of cancer cells. CCL22-induced addiction to FAK was demonstrated by the persistent suppression of tumor progression upon FAK-specific inhibition. Mechanistically, we identified that diacylglycerol kinase α (DGKα) acted as a signaling adaptor to link the CCL22 receptor C-C motif chemokine receptor 4 (CCR4) and FAK and promoted CCL22-induced activation of the FAK/AKT pathway. CCL22/CCR4 signaling activated the intracellular Ca2+/phospholipase C-γ1 (PLC-γ1) axis to stimulate the phosphorylation of DGKα at a tyrosine residue (Tyr335) and promoted the translocation of DGKα to the plasma membrane to assemble the DGKα/FAK signalosome, which critically contributed to regulating sensitivity to FAK inhibitors in cancer cells. The identification of TAM-driven intratumoral FAK addiction provides opportunities for utilizing the tumor-promoting microenvironment to achieve striking anticancer effects.

Expression and significance of TOLL2, TARC and MDC in placenta tissue of pregnant patients infected with syphilis.

This study was developed to investigate the expression of TOLL2, TARC and MDC in placenta tissue of pregnant patients infected with syphilis and their clinical significance. For this aim, placenta samples were collected from five pregnant patients co-infected with syphilis and five undergoing full-term delivery before RT-PCR was performed to detect the mRNA expression of TLR2, TARC and MDC genes. The protein expression of TLR2, TARC and MDC genes was examined by Western Blotting. Results showed that TLR2, TARC and MDC were expressed in placental syncytiotrophoblast cells of patients with pregnancy-associated syphilis infection. TLR2 level was found significantly higher in placenta tissue of patients with pregnancy-associated syphilis infection compared with normal placenta tissue (P<0.05), so were TARC (P<0.05) and MDC genes (P<0.05). It is concluded that TOLL2, TARC and MDC levels significantly increased in the placenta tissue of pregnant patients infected with syphilis, suggesting that the three genes were involved in the molecular pathology of the patients.

Macrophage-derived CCL23 upregulates expression of T-cell exhaustion markers in ovarian cancer.

BACKGROUND: Macrophages are an important component of the tumour immune microenvironment (TME) and can promote tumour growth and metastasis. Macrophage-secreted chemokine-ligand-23 (CCL23) induces ovarian cancer cell migration via chemokine-receptor 1 (CCR1). However, the effect of CCL23 on other immune cells in the TME is unknown. METHODS: CCL23 levels were measured by ELISA. The expression of surface markers in exhaustion assays was quantified by flow cytometry. Signalling pathways were identified by phosphokinase array and validated by western blot. RESULTS: Ascites from patients with high-grade serous ovarian cancer (HGSC) contain high levels of CCL23. Similarly, significantly higher CCL23 levels were found in plasma from HGSC patients compared to healthy individuals. RNA-seq analysis of ovarian cancer tissues from TCGA showed that expression of CCL23 correlated with the presence of macrophages. In tissues with high levels of CCL23 and macrophage content, the fraction of CD8 + T cells expressing exhaustion markers CTLA-4 and PD-1 were significantly higher compared to low-level CCL23 tissues. In vitro, CCL23 induced upregulation of immune checkpoint proteins on CD8 + T cells, including CTLA-4, TIGIT, TIM-3 and LAG-3 via phosphorylation of GSK3ß in CD8 + T cells. CONCLUSIONS: Our data suggest that CCL23 produced by macrophages contributes to the immune-suppressive TME in ovarian cancer by inducing an exhausted T-cell phenotype.

CCL22 mutations drive natural killer cell lymphoproliferative disease by deregulating microenvironmental crosstalk.

Chronic lymphoproliferative disorder of natural killer cells (CLPD-NK) is characterized by clonal expansion of natural killer (NK) cells where the underlying genetic mechanisms are incompletely understood. In the present study, we report somatic mutations in the chemokine gene CCL22 as the hallmark of a distinct subset of CLPD-NK. CCL22 mutations were enriched at highly conserved residues, mutually exclusive of STAT3 mutations and associated with gene expression programs that resembled normal CD16dim/CD56bright NK cells. Mechanistically, the mutations resulted in ligand-biased chemokine receptor signaling, with decreased internalization of the G-protein-coupled receptor (GPCR) for CCL22, CCR4, via impaired ß-arrestin recruitment. This resulted in increased cell chemotaxis in vitro, bidirectional crosstalk with the hematopoietic microenvironment and enhanced NK cell proliferation in vivo in transgenic human IL-15 mice. Somatic CCL22 mutations illustrate a unique mechanism of tumor formation in which gain-of-function chemokine mutations promote tumorigenesis by biased GPCR signaling and dysregulation of microenvironmental crosstalk.