Analysis of the Peripheral Blood Helper T-Cell 17- Cell Level and Monocyte/Lymphocyte Ratio for Colorectal Cancer Prognosis Prediction

Objective: To investigate the value of peripheral blood helper T cell 17 cell level and monocyte/lymphocyte ratio to predict the prognosis of colorectal cancer patients. Methods: 74 colorectal cancer patients who attended Hospital 960 from January 2021 to January 2022 were retrospectively analyzed. Clinical data of the patients were collected, including gender, age, and histologic type. Immunohistochemical indexes such as Th17 cell level and monocyte/ lymphocyte ratio in the peripheral blood of patients were also collected. The prognosis of patients after treatment, as well as peripheral blood Th17 and MLR levels, were observed and analyzed. Results: After follow-up after treatment, in the final 74 patients, the prognosis was good in 32 patients, accounting for 43.24%, and the prognosis was bad in 42 patients, accounting for 56.76%. There were no significant differences between the average age and tumor diameters of the good prognosis and poor prognosis groups (P > 0.05). However, the TNM staging, intervention taken, differentiation degree, presence of distant metastasis, presence of lymph node metastasis, Th17 level, and MLR level are significantly different between the two groups (P < 0.05). Conclusion: Peripheral blood Th17 and MLR have predictive value for the prognosis of colorectal cancer patients, and high levels of peripheral blood Th17 and MLR imply poor prognosis. The detection of peripheral blood Th17 and MLR levels is simple and convenient and can be used as indicators to provide a reference for the prognostic assessment of colorectal cancer patients.

Interaction between Kynurenine and Aryl Hydrocarbon Receptor in Regulating the Balance of T helper 17 Cells and Regulatory T-cells in Decidua during Early Gestation

Objective:To investigate whether kynurenine/aryl hydrocarbon receptor(AHR)affects the maternal-fetal tolerance by involving the differentiation of T helper 17(Th17)/regulatory T(Treg)cells,and to provide theoretical basic for new treatment of unexplained abortion.Methods:Flow cytometry(FCM)was used to detect the expression of AHR in peripheral/decidual CD4+T,Treg,and Th17 cells.The effect of Kyn on the differentiation of peripheral/decidual naïve T-cells under Treg-/Th17-polarizing condition was detected by FCM;enzyme-linked immunosorbent assay was performed to examine the level of Kyn in villus and decidual tissues from normal pregnancy(NP)and unexplained abortion(UA).Student’s t-test in the case of two groups or one-way ANOVA in multiple groups was used.Results:AHR expression in CD4+T-cells was decreased in decidua versus blood in early pregnancy(P<0.0001).Kyn could promote the differentiation of peripheral and decidual naïve T-cells to Th17 cells under Treg-polarizing conditions(P<0.01).There was no statistical significance about the concentration of Kyn in decidual or villi tissues between NP and UA,and compared with NP,the expression of AHR in decidual CD4+T-cells from UA was increased(P<0.001).Conclusions:Kyn/AHR promotes Th17 and restricts Treg cells’differentiation,which is involved in maintaining the balance of Treg/Th17 cells at the maternal-fetal interface.

Impaired balance of T helper 17/T regulatory cells in carbon tetrachloride-induced liver fibrosis in mice

AIM: To investigate the effect of T helper (Th) 17/T regulatory (Treg) cells on hepatic fibrosis in mice and its possible mechanism.

Increased CD4^+CD45RA^-FoxP3^(low) cells alter the balance between Treg and Th17 cells in colitis mice

AIM To investigate the role of regulatory T cell(Treg) subsets in the balance between Treg and T helper 17(Th17) cells in various tissues from mice with dextran sulfate sodium-induced colitis.METHODS T r e g c e l l s, T r e g c e l l s u b s e t s, T h 1 7 c e l l s, a n d CD4+CD25+FoxP 3+IL-17+ cells from the lamina propria of colon(LPC) and other ulcerative colitis(UC) mouse tissues were evaluated by flow cytometry. Forkhead box protein 3(FoxP 3), interleukin 17A(IL-17A), and RORC m RNA levels were assessed by real-time PCR, while interleukin-10(IL-10) and IL-17 A levels were detected with a Cytometric Beads Array.RESULTS In peripheral blood monocytes(PBMC), mesenteric lymphnode(MLN), lamina propria of jejunum(LPJ) and LPC from UC mice, Treg cell numbers were increased(P < 0.05), and FoxP 3 and IL-10 mR NA levels were decreased. Th17 cell numbers were also increased in PBMC and LPC, as were IL-17 A levels in PBMC, LPJ, and serum. The number of FrI subset cells(CD4+CD45RA+FoxP 3low) was increased in the spleen, MLN, LPJ, and LPC. FrI I subset cells(CD4+CD45RA-Fox P3high) were decreased among PBMC, MLN, LPJ, and LPC, but the number of Fr III cells(CD4+CD45RA-FoxP 3low) and CD4+CD25+FoxP 3+IL-17A+ cells was increased. Fox P3 m RNA levels in CD4+CD45RA-Fox P3 low cells decreased in PBMC, MLN, LPJ, and LPC in UC mice, while IL-17 A and RORC mR NA increased. In UC mice the distribution of Treg, Th17 cells, CD4+CD45RA-FoxP 3high, and CD4+CD45RA-FoxP 3low cells was higher in LPC relative to other tissues.CONCLUSION Increased numbers of CD4+CD45RA-FoxP 3low cells may cause an imbalance between Treg and Th17 cells that is mainly localized to the LPC rather than secondary lymphoid tissues.

Involvement of glycated albumin in adipose-derived-stem cellmediated interleukin 17 secreting T helper cell activation

BACKGROUND Advanced glycation end products(AGE)are a marker of various diseases including diabetes,in which they participate to vascular damages such as retinopathy,nephropathy and coronaropathy.Besides those vascular complications,AGE are involved in altered metabolism in many tissues,including adipose tissue(AT)where they contribute to reduced glucose uptake and attenuation of insulin sensitivity.AGE are known to contribute to type 1 diabetes(T1D)through promotion of interleukin(IL)-17 secreting T helper(Th17)cells.AIM To investigate whether lean adipose-derived stem cells(ASC)could be able to induce IL-17A secretion,with the help of AGE.METHODS As we have recently demonstrated that ASC are involved in Th17 cell promotion when they are harvested from obese AT,we used the same co-culture model to measure the impact of glycated human serum albumin(G-HSA)on human lean ASC interacting with blood mononuclear cells.IL-17A and pro-inflammatory cytokine secretion were measured by ELISA.Receptor of AGE(RAGE)together with intercellular adhesion molecule 1(ICAM-1),human leukocyte Antigen(HLA)-DR,cluster of differentiation(CD)41,and CD62P surface expressions were measured by cytofluorometry.Anti-RAGE specific monoclonal antibody was added to co-cultures in order to evaluate the role of RAGE in IL-17A production.RESULTS Results showed that whereas 1%G-HSA only weakly potentiated the production of IL-17A by T cells interacting with ASC harvested from obese subjects,it markedly increased IL-17A,but also interferon gamma and tumor necrosis factor alpha production in the presence of ASC harvested from lean individuals.This was associated with increased expression of RAGE and HLA-DR molecule by cocultured cells.Moreover,RAGE blockade experiments demonstrated RAGE specific involvement in lean ASC-mediated Th-17 cell activation.Finally,platelet aggregation and ICAM-1,which are known to be induced by AGE,were not involved in these processes.CONCLUSION Thus,our results demonstrated that G-HSA potentiated lean ASC-mediated IL-17A production in AT,suggesting a new mechanism by which AGE could contribute to T1D pathophysiology.

Expression of Helper T Cell Type 17 and CD4^(+)CD25^(+)Tregs in AMA-M2 Positive PBC Patients

Objective:To investigate the expression and impact of helper T cell type 17 and CD4^(+)CD25^(+)regulatory T(Treg)cells in anti-mitochondrial M2 antibody(AMA-M2)positive primary biliary cholangitis(PBC)patients.Methods:Thirty PBC patients with positive AMA(M2 type)(antibody titer above 1:320)by indirect immunofluorescence assay under the Affiliated Hospital of Hebei University from November 2021 to August 2022 were selected as the experimental group,while 30 healthy individuals were selected as controls.The subjects were observed and analyzed for AFP-L3 and immunoglobulin expression.Results:The levels of Th17,Treg,Th17/Treg,interleukin(IL)-17A,IL-2,IL-10,and transforming growth factor(TGF)-β1 cytokines of the experimental group were 2.61±0.48,1.15±0.54,2.41±0.47,310.94±21.14,276.36±36.12,317.89±28.97,and 197.48±31.04,respectively,while those of the control group were 1.14±0.58,0.88±0.29,1.47±0.25,9.69±1.26,57.69±2.45,154.01±19.87,and 514.36±36.12,respectively,wherein P<0.05;the CD4^(+),CD8^(+),and CD4^(+)/CD8^(+)of the experimental group were 39.48±4.19,20.12±4.41,and 1.76±0.14,respectively,while those of the control group were 35.78±4.21,22.01±4.16,and 1.51±0.13,respectively,wherein P<0.05.Conclusion:In patients with PBC,there is a significant imbalance in Th17/Treg cells.Il-17A,IL-2,IL-10,and TGF-β1 cytokines play important roles in the differentiation and functional expression of both Th17 and Treg cells.

Clinical significance of changes in the Th17/Treg ratio in autoimmune liver disease

AIM To investigate the levels, ratios, and clinical significance of T helper 17(Th17) cells and regulatory T(Treg) cells in the peripheral blood of patients with autoimmune liver disease(AILD). METHODS F o r t y-t w o A I L D p a t i e n t s w e r e i n c l u d e d i n t h e experimental group(group E), and 11 healthy subjects were recruited as the control group(group C). Flow cytometry was performed to determine the percentages of Th17 and Treg cells in peripheral blood lymphocytes. Furthermore, a range of biochemical indices was measured simultaneously in the blood of group E patients. RESULTS The percentage of Th17 cells and the Th17/Treg ratio were higher in group E than in group C(P < 0.01), whereas the percentage of Tregs was lower in the group E patients(P < 0.05). Patients in group E who were admitted with AILD in the active stage showed significantly higher Th17 percentages and Th17/Treg ratios than those measured in patients with AILD in remission(P < 0.05). In addition, among patients with AILD in the active stage, individuals that remained unhealed after hospitalization showed significantly higher baseline values of the Th17 percentage and the Th17/Treg ratio than those detected in patients who improved after treatment(P < 0.05). The results suggested that imbalance in the Th17/Treg ratio plays an important role in the pathogenesis and development of AILD.CONCLUSION A high Th17/Treg ratio appears to predict poor shortterm prognosis in patients with AILD in the active stage.

T helper cell dysregulation with hepatitis B and rebalance with glucocorticoids

AIM: To investigate T helper 17/regulatory T cell alterations in early severe hepatitis B and the effect of glucocorticoids.

Dysregulation of mucosal immune response in pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD) includes Crohn's disease and ulcerative colitis. The exact etiology and pathology of IBD remain unknown. Available evidence suggests that an abnormal immune response against the microorganisms in the intestine is responsible for the disease in genetically susceptible individuals. Dysregulation of immune response in the intestine plays a critical role in the pathogenesis of IBD, involving a wide range of molecules including cytokines. On the other hand, besides T helper (Th) 1 and Th2 cell immune responses, other subsets of T cells, namely Th17 and regulatory T cells, are likely associated with disease progression. Studying the interactions between various constituents of the innate and adaptive immune systems will certainly open new horizons of the knowledge about the immunologic mechanisms in IBD. (c) 2014 Baishideng Publishing Group Co., Limited. All rights reserved.

Predictive value of Th17 and Treg cells at baseline for HBsAg loss in chronic hepatitis B patients with low HBsAg quantification treated with pegylated interferon and nucleos(t)ide analogue

Background and aims:The primary goal of chronic hepatitis B(CHB)treatment is to reduce hepatitis B surface antigen(HBsAg).T helper 17(Th17)and regulatory T(Treg)cells are essential for the development of CHB.However,how Th17 and Treg cells contribute to HBsAg loss is still unknown.Therefore,this study aimed to search for the predictive value of Th17 and Treg cells for HBsAg loss in CHB patients with low HBsAg quantification.Methods:The study included 99 hepatitis B e antigen(HBeAg)-negative CHB patients who had completed a year of nucleos(t)ide analogue(NA)monotherapy and had received both NA and pegylated interferon(PEG-IFN)treatment for less than 96 weeks(96 wk).In the cured group,48 patients lost HBsAg within 48 wk,while 51 patients did not(uncured group).Blood samples and clinical data were collected for research.Results:During PEG-IFN and NA combination therapy,the proportion of Th17 cells in the cured group increased significantly,while the proportion of Treg cells in the uncured group increased.From 0 to 24 wk,the proportion of Th17 cells in the cured group was significantly higher than in the uncured group,while the opposite was true for Treg cells.Patients with alanine aminotransferase(ALT)2.5 upper limit of normal(ULN)at 12 wk had a higher proportion of Th17 cells and a lower proportion of Treg cells than those with ALT<2.5 ULN at 12 wk.Additionally,the proportion of Th17 cells is inversely associated with the level of HBsAg,whereas the level of Treg cells is positively related to HBsAg quantification.The clinical cure index,including age,HBsAg quantification,and the proportions of Th17 and Treg cells,had a higher area under the curve(0.957)for predicting HBsAg loss when compared to the proportions of Th17 and Treg cells and HBsAg quantification alone.Conclusions:Combined with quantification of HBsAg,the proportions of Th17 cells and Treg cells at baseline can be used as good predictors of HBsAg loss in patients with low HBsAg quantification treated with NA and PEG-IFN.

Early Changes in Circulatory T Helper Type 1, 2, and 17 Cells of Patients with Out-of-Hospital Cardiac Arrest after Successful Cardiopulmonary Resuscitation

Background： Immune disorder is an important feature of patients with out-of-hospital cardiac arrest （OHCA） after the return of spontaneous circulation （ROSC）. We investigated the expression of circulatory T helper type （Th）1, Th2, and Th 17 cells to explore the early immune alteration in OHCA patients after ROSC. Methods： During July-September 2016 and March-September 2017, 65 consecutive OHCA patients with ROSC 〉 12 h and 30 healthy individuals were enrolled in this study. Clinical and 28-day survival data were collected. Peripheral blood samples were analyzed to evaluate the expression of Th1/Th2/Th 17 cells by flow cytometry from OHCA patients after ROSC on days l and 3 and from healthy individuals. Results： Compared with healthy individuals, T lymphocyte counts and Thl cell counts decreased on days 1 and 3 after ROSC （1464 [1198, 2152] vs. 779 [481, 1140] vs. 581 [324, 1118/μl,χ^2= 30.342, P 〈 0.001; 154 [90, 246] vs. 39 [19, 78] vs. 24 [12, 53]μl, χ^2 = 42.880, P〈 0.001）, and Th2 and Th17 cell counts decreased on day 3 （17.0 [10.8, 24.0] vs. 9.0 [3.0, 15.5]μl, Z= -3.228, P= 0.001; 4.7 [2.7, 9.1] vs. 2.7 [1.0, 6.5]μl, Z = -2.294, P = 0.022）. No change in CD4＋/CD3＋ lymphocyte ratio was seen on day 1 or day 3 （57.9 [49.4, 63.0] vs. 55.4 [46.5, 66.5] vs. 55.4 [50.2, 67.0]%, χ^2 = 0.171, P = 0.918）. Th1/CD4＋ lymphocyte ratio decreased on days 1 and 3 （19.0 [14.0, 24.9] vs. 9.3 [4.6, 13.9] vs. 9.5 [4.9, 13.6]%, χ^2= 25.754, P 〈 0.001）, and Th2/CD4＋ lymphocyte ratio increased on day 1 and decreased on day 3 （1.9 [1.2, 2.5] vs. 2.5 [1.6, 4.0] vs. 1.9 [1.6, 3.81%,χ^2= 6.913, P = 0.032）. Thl/Th2 cell ratio also decreased on both clays （9.4 [7.3, 13.5] vs. 3.1 [1.9, 5.6] vs. 4.2 [2.8, 5.9], χ^2 = 44.262, P 〈 0.001 ）. Despite an upward trend in the median of Th 17/CD4＋ lymphocyte ratio in OHCA patients, there was no significant difference compared with healthy individuals （0.9 [0.4, 1.2] vs. 0.7 [0.4, 1.2] vs. 0.6 [0.3, 1.01%, χ^2= 2.620, P = 0.270）. The dynamic expression of Th1/Th2/Th 17 cells on days 1 and 3 were simultaneously analyzed in 28/53 OHCA patients who survived 〉3 days; patients were divided into survivors （n = 10） and nonsurvivors （n = 18） based on 28-day survival. No significant differences in Th1/Th2/Th 17 cell counts, ratios in CD4＋ lymphocytes, and Th1/Th2 cell ratio were seen between survivors and nonsurvivors on both days （all P 〉 0.05）. There was no difference over time in both survivors and nonsurvivors （all P 〉 0.05）. Conclusion： Downregulated T lymphocyte counts, including Th1/Th2/Th17 subsets and Th1/Th2 cell ratio imbalance, occur in the early period after ROSC, that may be involved in immune dysfunction in OHCA patients.

Immune and microRNA responses to Helicobacter muridarum infection and indole-3-carbinol during colitis

BACKGROUND Indole-3-carbinol(I3C)and other aryl hydrocarbon receptor agonists are known to modulate the immune system and ameliorate various inflammatory and autoimmune diseases in animal models,including colitis induced by dextran sulfate sodium(DSS).MicroRNAs(miRNAs)are also gaining traction as potential therapeutic agents or diagnostic elements.Enterohepatic Helicobacter(EHH)species are associated with an increased risk of inflammatory bowel disease,but little is known about how these species affect the immune system or response to treatment.AIM To determine whether infection with an EHH species alters the response to I3C and how the immune and miRNA responses of an EHH species compare with responses to DSS and inflammatory bowel disease.METHODS We infected C57BL/6 mice with Helicobacter muridarum(H.muridarum),with and without DSS and I3C treatment.Pathological responses were evaluated by histological examination,symptom scores,and cytokine responses.MiRNAs analysis was performed on mesenteric lymph nodes to further evaluate the regional immune response.RESULTS H.muridarum infection alone caused colonic inflammation and upregulated proinflammatory,macrophage-associated cytokines in the colon similar to changes seen in DSS-treated mice.Further upregulation occurred upon treatment with DSS.H.muridarum infection caused broad changes in mesenteric lymph node miRNA expression,but colitis-associated miRNAs were regulated similarly in H.muridarum-infected and uninfected,DSS-treated mice.In spite of causing colitis exacerbation,H.muridarum infection did not prevent disease amelioration by I3C.I3C normalized both macrophage-and T cell-associated cytokines.CONCLUSION Thus,I3C may be useful for inflammatory bowel disease patients regardless of EHH infection.The miRNA changes associated with I3C treatment are likely the result of,rather than the cause of immune response changes.

The regulation of the Treg/Th 17 balance by mesenchyma stem cells in human systemic lupus erythematosus

Background and objective： Umbilical cord （UC）-derived mesenchymal stem cells （MSCs） have shown immunoregulation of various immune cells. The aim of this study was to investigate the mechanism of UC MSCs in the regulation of peripheral regulatory T cells （Treg） and T helper 17 （Th17） cells in patients with systemic lupus erythematosus （SLE）. Methods： Thirty patients with active SLE, refractory to conventional therapies, were given UC MSCs infusions. The percentages of peripheral blood CD4＋CD25＋Foxp3＋ regulatory T cells （Treg） and CD3＋CD8-1L17A＋ Th17 cells and the mean fluorescence intensities （MFI） of Foxp3 and IL- 17 were measured at I week, I month, 3 months, 6 months, and 12 months after MSCs transplantation （MSCT）. Serum cytokines, including transforming growth factor beta （TGF-β）, tumor necrosis factor alpha （TNF-α）, interleukin 6 （IL-6）, and IL-17A were detected using ELISA. Peripheral blood mononuclear cells from patients were collected and co-cultured with UC MSCs at ratios of 1：1, 10：1, and 50：1, respectively, for 72 h to detect the proportions of Treg and Th17 cells and the MFIs of Foxp3 and IL-17 were determined by flow cytometry. The cytokines in the supernatant solution were detected using ELISA. Inhibitors targeting TGF-β, IL-6, indoleamine 2,3-dioxygenase （IDO）, and prostaglandin E2 were added to the co-culture system, and the percentages of Treg and Th17 cells were observed. Results： The percentage of peripheral Treg and Foxp3 MFI increased 1 week, 1 month, and 3 months after UC MSCs transplantation, while the Th17 proportion and MFI of IL-17 decreased 3 months, 6 months, and 12 months after the treatment, along with an increase in serum TGF-β at I week, 3 months, and 12 months and a decrease in serum TNF-a beginning at I week. There were no alterations in serums IL-6 and IL-17A before or after MSCT. In vitro studies showed that the UC MSCs dose-dependently up-regulated peripheral Treg proportion in SLE patients, which was not depended on cell-cell contact. However, the down-regulation of Th17 cells was not dose-dependently and also not depended on cell-cell contact. Supernatant TGF-α and IL-6 levels significantly increased, TNF-a significantly decreased, but IL-17A had no change after the co-culture. The addition of anti-TGF-β antibody significantly abrogated the up-regulation of Treg, and the addition of PGE2 inhibitor significantly abrogated the down-regulation of Th17 cells. Both anti-lL-6 antibody and IDO inhibitor had no effects on Treg and Th17 cells. Conclusions： UC MSCs up-regulate Treg and down-regulate Th 17 cells through the regulation of TGF-β and PGE2 in lupus patients.

The cytokine milieu in the interplay of pathogenic Th1/ Th17 cells and regulatory T cells in autoimmune disease

The propagation and regulation of an immune response is driven by a network of effector and regulatory T(Treg)cells.The interplay of effector T and Treg cells determines the direction of the immune response towards inflammation or its resolution in an autoimmune disease setting.In autoimmune diseases,this interplay shifts the balance in favor of the development of autoreactive effector T cells,resulting in inflammatory pathology.The objective of an effective therapeutic approach for autoimmune disease is to restore this balance.In this review,we describe the characteristics and development of pathogenic T helper 1(Th1)and Th17 cells and the beneficial Treg cells in autoimmune diseases and the crucial roles of the cytokine milieu in influencing the balance of these T-cell subsets.Given the importance of cytokines,we discuss current immunotherapeutic strategies using cytokine or cytokine receptor antibodies for the treatment of autoimmune diseases.

Th17 cells are involved in mouse chronic obstructive pulmonary disease complicated with invasive pulmonary aspergillosis

Background:The incidence of chronic obstructive pulmonary disease(COPD)complicated with invasive pulmonary aspergillosis(IPA)has increased in the last two decades.The mechanism underpinning susceptibility to and high mortality of COPD complicated with IPA is unclear,and the role of T helper cells 17(Th17 cells)in the compound disease remains unknown.Therefore,this study aimed to assess the function of Th17 cells in COPD combined with IPA.Methods:COPD,IPA,and COPD+IPA mouse models were established in male wild type C57/BL6 mice.The amounts of Th17 cells and retinoic acid-related orphan receptorsγt(RORyt)were tested by flow cytometry.Then,serum interleukin(IL)-17 and IL-23.levels were detected by enzyme-linked immunosorbent assay(ELISA)in the control,COPD,IPA and COPD+IPA groups.In addition,COPD+IPA was induced in IL-17 knockout(KO)mice,for determining the role of Th17 cells in COPD+IPA.Results:Compared with the COPD group,the COPD+IPA group showed higher amounts of blood RORyt([35.09±16.12]%vs.[17.92±4.91]%,P=0.02)and serum IL-17(17.96±9.59 pg/mL vs.8.05±4.44 pg/mL,P=0.02),but blood([5.18±1.09]%vs.[4.15±0.87]%,P=0.28)and lung levels of Th17 cells(1.98±0.83]%vs.[2.03±0.98]%,P=0.91),lung levels of RORyt([9.58±6.93]%vs.[9.63±5.98]%,P=0.49)and serum IL-23(51.55±27.82 pg/mL us.68.70±15.20 pg/mL,P=0.15)showed no significant differences.Compared with the IPA group,the COPD+IPA group displayed lower amounts of blood([5.18±1.09]%vs.[9.21±3.56]%,P=0.01)and lung Th17 cells([1.98±0.83]%vs.[6.29±1.11]%,P=0.01)and serum IL-23(51.55±27.82 pg/mL vs.154.90±64.60 pg/mL,P=0.01)and IL-17(17.96±9.59 pg/mL uUs.39.81±2.37 pg/mL,P=0.02),while comparable blood([35.09±16.12]%Vs.[29.86±15.42]%,P=0.25)and lung levels of RORγt(9.58±6.93]%VUS,[15.10±2.95]%,P=0.18)were found in these two groups.Finally,Aspergillus load in IL-17 KO COPD+IPA mice was almost 2 times that of COPD+IPA mice(1,851,687.69±944,480.43"vs.892,958.10±686,808.80,t=2.32,P=0.02).Conclusion:These findings indicate that Th17 cells might be involved in the pathogenesis of COPD combined with IPA,with L-17 likely playing an antifungal role.