Focused evaluation of the roles of macrophages in chimeric antigen receptor (CAR) T cell therapy associated cytokine release syndrome

Cytokine release syndrome(CRS)is a major obstacle to the widespread clinical application of chimeric antigen receptor(CAR)T cell therapies.CRS can also be induced by infections(such as SARS-CoV-2),drugs(such as therapeutic antibodies),and some autoimmune diseases.Myeloid-derived macrophages play key roles in the pathogenesis of CRS,and participate in the production and release of the core CRS cytokines,including interleukin(IL)-1,IL-6,and interferon-γ.In this review,we summarize the roles of macrophages in CRS and discuss new developments in macrophage activation and the related mechanisms of cytokine regulation in CRS.

Refractory lymphoma treated with chimeric antigen receptor T cells combined with programmed cell death-1 inhibitor:A case report

BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a common aggressive non-Hodgkin's lymphoma(NHL),accounting for 30%-40%of adult NHL.Primary testicular(PT)lymphoma is an uncommon extranodal disease representing approximately 1%-2%of lymphoma.Approximately 30%–40%of patients are refractory to frontline therapy or relapse after complete remission.Refractory DLBCL responds poorly to other lines of chemotherapy,and experiences short-term survival.CASE SUMMARY We present a 41-year-old male patient who was diagnosed with PT-DLBCL.Further disease progression was observed after multiline chemotherapy.Chimeric antigen receptor T cells(CAR-T)therapy salvaged the patient.Unfortunately,a new mass was observed in the right adrenal area after six months.The patient was administered programmed cell death protein-1(PD-1)inhibitor therapy and maintained progression-free survival at more than 17 mo of follow-up.CONCLUSION Our findings support the potential benefit of CAR-T combined with PD-1 inhibitor therapies in this type of relapsed and refractory PT-DLBCL.

Programmed cell death protein-1 inhibitor combined with chimeric antigen receptor T cells in the treatment of relapsed refractory non- Hodgkin lymphoma: A case report

BACKGROUND Chimeric antigen receptor T cell(CART)therapy has benefited many refractory lymphoma patients,but some patients experience poor effects.Previous studies have shown that programmed cell death protein-1(PD-1)inhibitors can improve and prolong the therapeutic effect of CAR-T cell treatment.CASE SUMMARY A 61-year-old male presented with 15-d history of diarrhea and lower-limb edema.A large mass was detected in the pelvis,and pathology indicated non-Hodgkin diffuse large B-cell lymphoma.After three cycles of the R-CHOP chemotherapeutic regimen,the patient showed three subcutaneous nodules under the left armpit and both sides of the cervical spine.Pathological examination of the nodules indicated DLBCL again.The patient was diagnosed with relapsed and refractory diffuse large B-cell lymphoma.We recommended CAR-T cell treatment.Before treatment,the patient’s T cell function and expression of immune detection points were tested.Expression of PD-1 was obviously increased(52.7%)on cluster of differentiation(CD)3+T cells.The PD-1 inhibitor(3 mg/kg)was infused prior to lymphodepleting chemotherapy with fludarabine and cyclophosphamide.CAR-CD19 T cells of 3×10^(6)/kg and CAR-CD22 T cells 1×10^(6)/kg were infused,respectively.The therapeutic effect was significant,and the deoxyribonucleic acid copy numbers of CAR-CD19 T cells and CAR-CD22 T cells were stable.Presently,the patient has been disease-free for more than 12 mo.CONCLUSION This case suggests that the combination of PD-1 inhibitors and CAR-T cellsimproved therapeutic efficacy in B-cell lymphoma.

Chimeric Antigen Receptors and Regulatory T Cells:The Potential for HLA-Specific Immunosuppression in Transplantation

Chimeric antigen receptors(CARs)are a breakthrough in genetic engineering that have revolutio nized the field of adoptive cellular therapy(ACT).Cells expressing these receptors are rerouted to a predefined target by the inclusion of an antigen-specific binding region within the synthetic CAR construct.The advantage of cells with programmed specificity has been demonstrated clinically in the field of oncology,and it is clear that such cells have greater accuracy,potency,and reduced off-target therapeutic effects compared with their unmodified counterparts.In contrast to conventional T cells(Tconvs),regulatory T cells(Tregs)play a major role in suppressing immune activation and regulating the host immune response.CAR expression within Tregs has been proposed as a therapy for autoimmune and inflammatory diseases,graft-versus-host disease(GVHD),and organ transplant rejectio n.In the latter,they hold immense potential as mediators of immune tolerance for recipients of allotransplants.However,current research into CAR-Treg engineering is extremely limited,and there is uncertainty regarding optimal design for therapeutic use.This review examines the rationale behind the development of CAR-Tregs,their significance for human transplantation,potential designs,safety considerations,and comparisons of CAR-Tregs in transplantation models to date.

Human CD4- CD8- Invariant Natural Killer T Cells Promote IgG Secretion from B Cells Stimulated by Cross-Linking of Their Antigen Receptors

Immunoglobulin (Ig) M production can be induced by the interaction of thymus-independent type-2 (TI-2) antigen (Ag) with B cell Ag receptors (BCRs) without the involvement of conventional T cells;for IgG production through the same process, however, a second signal is required. Previous studies have reported that invariant natural killer T (iNKT) cells may be responsible for the second signal involved in IgG production. In the present study, we addressed whether human iNKT cells could participate in the production of Ig against TI-2 Ag in vitro. Two major distinct subsets of human iNKT cells, CD4+ CD8β- (CD4) and CD4- CD8β- [double negative (DN)] cells, were generated from peripheral blood monocytes from a healthy volunteer. BCR engagement, triggered by anti-IgM antibody stimulation, examined here as a model of BCR engagement triggered by TI-2 Ag, induced abundant IgM production by B cells. Both CD4 and DN iNKT cells reduced IgM production and conversely enhanced IgG production in a dose-dependent manner. In addition, IgG production by CD19+CD27- (naïve) and CD19+CD27+ (memory) B cells was predominantly promoted by DNiNKT cells rather than CD4 iNKT cells;nevertheless, IgM production by both B cell subsets was similarly reduced by either subset of iNKT cells. These results suggest that the DN iNKT subsets may preferentially promote Ig class switching by B cells upon stimulation with TI-2 Ag.

Relevant nursing measures for the adverse reactions associated with chimeric antigen receptor T cells(CAR-T) immunotherapy: a systematic review of case reports

Objective: Cytokine release syndrome (CRS) and tumor lysis syndrome (TLS) that occur after chimeric antigen receptor T (CAR-T) cells are reinfused, which severely affect the survival and prognosis of patients. Although several articles have reported on the care of CAR-T cell immunotherapy, the quality of the study and the effectiveness of holistic nursing interventions have not been systematically reviewed. The purpose of this study was to systematically evaluate the existing holistic nursing interventions of CAR-T cell immunotherapy. Methods: A literature search for keywords was performed in PubMed, EMBASE, the Cochrane Library, CNKI, CBM, and Wanfang Data from its inception until January 2018. Studies were deemed eligible if they comprised patients with tumor receiving CAR-T cell immunotherapy, described the holistic nursing process, and were published in Chinese and English. Results: A total of 6 articles on holistic nursing interventions of CAR-T cell immunotherapy are reported, and the nursing methods and results of each article are analyzed. The quality of the studies included was medium. All nursing measures were considered effective. Conclusions: Holistic nursing programs reduce the incidence of CRS and TLS and improve the quality of life of cancer patients.

ANALYSIS OF T CELL CLONALITY BY CDR3 SIZE OF T-CELL ANTIGEN RECEPTOR Vβ REPERTOIRE IN HCL AND c-ALL

Objective: To analyze the distribution and clonality of TCR Vβ subfamily T cells in hairy cell leukemia (HCL) and common-acute lymphoblastic leukemia (c-ALL). Methods: Peripheral blood mononuclear cell samples from 3 cases of HCL and 1 case of c-ALL were investigated for analysis of complementarity determining region 3 (CDR3) size of T cell receptor Vβ repertoire using reverse transcriptase-polymerase chain reaction (RT-PCR). The products were further analyzed by genescan to identify T cell clonality. Results: Some Vβ subfamily PCR products from 4 patients contained monopeak (monoclone) or a dominant peak (oligoclone). In contrast, multipeak (polyclone) distributions were found in all Vβ subfamily PCR products from normal control cases. Conclusion: T cell clonal expansion may be found in HCL and c-ALL cases that may indicate a host response directed against leukemia related antigen. In addition, it may be useful to detect the minimal residual disease.

T cells expressing a LMP1-specific chimeric antigen receptor mediate antitumor effects against LMP1-positive nasopharyngeal carcinoma cells in vitro and in vivo

T cells modified with chimeric antigen receptor are an attractive strategy to treat Epstein-Barr virus（EBV） associated malignancies.The EBV latent membrane protein 1（LMP1） is a 66-KD integral membrane protein encoded by EBV that consists of transmembrane-spanning loops.Previously,we have identified a functional signal chain variable fragment（scFv） that specifically recognizes LMP1 through phage library screening.Here,we constructed a LMP1 specific chimeric antigen receptor containing anti-LMP1 scFv,the CD28 signalling domain,and the CD3ζchain（HELA/CAR）.We tested its functional ability to target LMP1 positive nasopharyngeal carcinoma cells.HELA/CAR cells were efficiently generated using lentivirus vector encoding the LMP1-specific chimeric antigen receptor to infect activated human CD3＋ T cells.The HELA/CAR T cells displayed LMP1 specific cytolytic action and produced IFN-γ and IL-2 in response to nasopharyngeal carcinoma cells overexpressing LMP1.To demonstrate in vivo anti-tumor activity,we tested the HELA/CAR T cells in a xenograft model using an LMP1 overexpressing tumor.Intratumoral injection of anti-LMP1 HELA/CAR-T cells significantly reduced tumor growth in vivo.These results show that targeting LMP1 using HELA/CAR cells could represent an alternative therapeutic approach for patients with EBV-positive cancers.

Chimeric antigen receptor-engineered T-cell therapy for liver cancer

Background: Chimeric antigen receptor-engineered T-cell(CAR-T) therapy is a newly developed immunotherapy used in the treatment of cancers. Because CAR-T therapy has shown great success in treating CD19-positive hematological malignancies, its application has been explored in the treatment of solid tumors, such as liver cancer. In this review, we discuss the immune characteristics of liver cancer, the obstacles encountered during the application of CAR-T therapy, and preclinical and clinical progress in the use of CAR-T therapy in patients with liver cancer.Data sources: The data on CAR-T therapy related to liver cancers were collected by searching Pub Med and the Web of Science databases prior to December 2017 with the keywords "chimeric antigen receptor","CAR-T", "liver cancer", "hepatocellular carcinoma", and "solid tumor". Additional articles were identified by manual search of references found in the primary articles. The data for clinical trials were collected by searching Clinical Trials.gov.Results: The liver has a tolerogenic nature in the intrahepatic milieu and its tumor microenvironment significantly affects tumor progression. The obstacles that reduce the efficacy of CAR-T therapy in solid tumors include a lack of specific tumor antigens, limited trafficking and penetration of CAR-T cells to tumor sites, and an immunosuppressive tumor microenvironment. To overcome these obstacles, several strategies have emerged. In addition, several strategies have been developed to manage the side effects of CAR-T, including enhancing the selectivity of CARs and controlling CAR-T activity. To date, no clinical trials of CAR-T therapy against HCC have been completed. However, preclinical studies in vitro and in vivo have shown potent antitumor efficacy. Glypican-3, mucin-1, epithelial cell adhesion molecule, carcinoembryonic antigen, and other targets are currently being studied.Conclusions: The application of CAR-T therapy for liver cancer is just beginning to be explored and more research is needed. However, we are optimistic that CAR-T therapy will offer a new approach for the treatment of liver cancers in the future.

Mast cell density and the context of clinicopathological parameters and expression of p185,estrogen receptor,and proliferating cell nuclear antigen in gastric carcinoma

AIM:To investigate the relationship between the mast cell density(MCD)and the context of clinicopathological parameters and expression of p185,estrogen receptor(ER), and proliferating cell nuclear antigen(PCNA)in gastric carcinoma. METHODS:Mast cell,p185,ER,and PCNA were detected using immunohistochemical S-P labeling method.Mast cell was counted in tissue of gastric carcinoma and regional lymph nodes respectively,and involved lymph nodes(ILN)were examined as usual. RESULTS:MCD was significantly related to both age and depth of penetration(x^2=4.688,P<0.05 for age and x^2=9.350, P<0.01 for depth of penetration)between MCD>21/0.03 mm^2 and MCD≤21/0.03 mm^2 in 100 patients;MCD in 1-6 ILN group patients was significantly higher than that in 7-15 ILN or>15 ILN group patients(u=6.881,8.055,P<0.01); There were significant differences intergroup in positive expression rate of p185,ER and PCNA between MCD>21/ 0.03 mm^2 and MCD≤21/0.03 mm^2 in 100 patients. CONCLUSION:Mast cell may have effect on inhibiting invasive growth of tumor,especially in the aged patients; The number of mast cells,in certain degree,may predicate the number of involved lymph nodes,which is valuable for assessment of prognosis;MCD was related to the expression of p185,ER,and PCNA in gastric carcinoma.It suggests that mast cell accumulation may inhibit the proliferation and the dissemination of the gastric carcinoma. INTRODUCTION Recently,many studies have reported on the association of mast cell with various tumorst.In several malignancies,mast cell has been found to correlate with growth,penetration and prognosis of tumor.Therefore,our study was undertaken to investigate the relationship between the mast cell density (MCD)and the context of clinicopathological parameters and expression of p 185,estrogen receptor(ER),and proliferating cell nuclear antigen(PCNA)in gastric carcinoma.

T_H1 AND T_H2 CELL ANTIGEN RECEPTORS IN EXPERIMENTAL LEISHMANIASIS

The complexity and ehronicity of parasitic infections have obscured the identification of biologically relevant antigens.Analysis of the T cell receptor repertoire used by mice infected with leishmania major revealed the expansion of a restricted population of CD4+ cells.These cells expressed the Vα 8-JαTA72,Vβ4 heterodimer in both progressive infection and protective immunity and across several major histocompatibility haplotypes.Thus,the same immunodominant parasite epitope drives the disparate outcomes of this infectious process, suggesting that candidate vaccine antigens selected by screening of immune individuals may be capable of exacerbating disease in genetically susceptible individuals.

Chidamide and sintilimab combination in diffuse large B-cell lymphoma progressing after chimeric antigen receptor T therapy

BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is curable with first-line chemoimmunotherapy but patients with relapsed/refractory(R/R)DLBCL still face a poor prognosis.For patients with R/R DLBCL,the complete response rate to traditional next-line therapy is only 7%and the median overall survival is 6.3 mo.Recently,CD19-targeting chimeric antigen receptor T cells(CAR-T)have shown promise in clinical trials.However,approximately 50%of patients treated with CAR-T cells ultimately progress and few salvage therapies are effective.CASE SUMMARY Here,we report on 7 patients with R/R DLBCL whose disease progressed after CAR-T infusion.They received a PD-1 inhibitor(sintilimab)and a histone deacetylase inhibitor(chidamide).Five of the 7 patients tolerated the treatment without any serious adverse events.Two patients discontinued the treatment due to lung infection and rash.At the 20-mo follow-up,the median overall survival of these 7 patients was 6 mo.Of note,there were 2 complete response rates(CRs)and 2 partial response rates(PRs)during this novel therapy,with an overall response rate(ORR)of 57.1%,and one patient had a durable CR that lasted at least 20 mo.CONCLUSION In conclusion,chidamide combined with sintilimab may be a choice for DLBCL patients progressing after CD19-targeting CAR-T therapy.

Advancement of chimeric antigen receptor-natural killer cells targeting hepatocellular carcinoma

With the advance of genome engineering technology,chimeric antigen receptors(CARs)-based immunotherapy has become an emerging therapeutic strategy for tumors.Although initially designed for T cells in tumor immunotherapy,CARs have been exploited to modify the function of natural killer(NK)cells against a variety of tumors,including hepatocellular carcinoma(HCC).CAR-NK cells have the potential to sufficiently kill tumor antigen-expressing HCC cells,independent of major histocompatibility complex matching or prior priming.In this review,we summarize the recent advances in genetic engineering of CAR-NK cells against HCC and discuss the current challenges and prospects of CAR-NK cells as a revolutionary cellular immunotherapy against HCC.

Roles of antigen receptors and CA215 in the innate immunity of cancer cells

Antigen receptors, including immunoglobulins and T-cell receptors, are known to be widely expressed by cancer cells through unconfirmed mechanisms and for unknown purposes. Recently, a monoclonal antibody, designated as RP215, was generated against the ovarian cancer cell line, OC-3-VGH, and was shown to react with CA215, which consisted mainly of these cancer cell-expressed antigen receptors. Experimental evidence has clearly indicated that cancerous immunoglobulins play significant roles in the growth and proliferation of cancer cells in vitro and in vivo. RP215 and anti-antigen receptor antibodies were equally effective in inducing apoptosis and complement-dependent cytotoxicity reactions to cultured cancer cells. Through gene regulation studies, both RP215 and antibodies against antigen-receptors were shown to affect more than a dozen of genes involved in cell proliferation (such as NFκB-1, IgG, P21, cyclin D1, ribosomal P1, and c-fos). Furthermore, selected toll-like receptor genes (TLR- 2, -3, -4, and -9) were also found to be highly regulated by both RP215 and anti-antigen receptor antibodies. For example, RP215 and anti-antigen receptor antibodies were found to both up-regulate TLR-2 and/or TLR-3 and down- regulate TLR-4 and TLR-9 intwo types of cancer cells. Based on these studies, it is reasonable to postulate that cancerous immunoglobulins play important roles in the modulation of the innate immune system to allow the growth and survival of cancer cells within the human body. Consequently, RP215 inits humanized forms may be utilized to target cancer cells for potential therapeutic purposes.

The effect of Chinese herbal medicine“heche assisted pregnancy recipe”on endometrial estrogen and progesterone receptor,proliferating cell nuclear antigen and vascular endothelial growth factor in the patients with infertility

Objectives:To investigate the effect of Chinese herbal medicine"heche assisted preg-nancy recipe (HCAPR)" on estrogen receptor(ER), progesterone receptor (PR), pro-lifierating cell nuclear antigen(PCNA) and vascular endothelial growth factor (VEGF)in endometrium of infertile women.Methods: The S-P immunohistochemical assay was used to observe expression ofER, PR , PCNA and VEGF in late proliferative phase before and after the HCAPR treat-ment.Results: After the treatment, the expression of ER,PR,PCNA and VEGF in nucleiof glandular epithelium and stromal cells was significantly stronger (all P＜0. 001) re-spectively than that before treatment , especially the expression of PCNA and VEGF.Conclusions: These results suggest that traditional Chinese medicine HCAPR oftonifying kidney and regulating menstruation increased the synthesis of ER,PR, PCNAand VEGF, which may promote normal growth and development of the endometrium ,improve the micro-environment of the endometrium, and enhance uterine receptivity.The evidence may provide theoretical basis for therapy infertility with Chinese herbalmedicine.

Adoptive immunotherapy for acute leukemia:New insights in chimeric antigen receptors

Relapses remain a major concern in acute leukemia. It is well known that leukemia stem cells(LSCs) hide in hematopoietic niches and escape to the immune system surveillance through the outgrowth of poorly immunogenic tumor-cell variants and the suppression of the active immune response. Despitethe introduction of new reagents and new therapeutic approaches, no treatment strategies have been able to definitively eradicate LSCs. However, recent adoptive immunotherapy in cancer is expected to revolutionize our way to fight against this disease, by redirecting the immune system in order to eliminate relapse issues. Initially described at the onset of the 90's, chimeric antigen receptors(CARs) are recombinant receptors transferred in various T cell subsets, providing specific antigens binding in a non-major histocompatibility complex restricted manner, and effective on a large variety of human leukocyte antigen-divers cell populations. Once transferred, engineered T cells act like an expanding "living drug" specifically targeting the tumor-associated antigen, and ensure long-term antitumor memory. Over the last decades, substantial improvements have been made in CARs design. CAR T cells have finally reached the clinical practice and first clinical trials have shown promising results. In acute lymphoblastic leukemia, high rate of complete and prolonged clinical responses have been observed after anti-CD19 CAR T cell therapy, with specific but manageable adverse events. In this review, our goal was to describe CAR structures and functions, and to summarize recent data regarding pre-clinical studies and clinical trials in acute leukemia.

The human application of gene therapy to re-program T-cell specificity using chimeric antigen receptors

The adoptive transfer of T cells is a promising approach to treat cancers. Primary human T cells can be modified using viral and non-viral vectors to promote the specific targeting of cancer cells via the introduction of exogenous T-cell receptors(TCRs) or chimeric antigen receptors(CARs). This gene transfer displays the potential to increase the specificity and potency of the anticancer response while decreasing the systemic adverse effects that arise from conventional treatments that target both cancerous and healthy cells. This review highlights the generation of clinical-grade T cells expressing CARs for immunotherapy, the use of these cells to target B-cell malignancies and, particularly, the first clinical trials deploying the Sleeping Beauty gene transfer system, which engineers T cells to target CD19+ leukemia and non-Hodgkin's lymphoma.

Regulatory T cells suppress autoreactive CD4^+ T cell response to bladder epithelial antigen

AIM： To investigate the role of regulatory T （Treg） cells in CD4^＋ T cell-mediated bladder autoimmune infammation. METHODS： Urothelium-ovalbumin （URO-OVA）/OT-II mice, a double transgenic line that expresses the membrane form of the model antigen （Ag） OVA as a self-Ag on the urothelium and the OVA-specific CD4^＋ T cell receptor specifc for the I-Ab/OVA323-339 epitope in the periphery, were developed to provide an autoimmune environment for investigation of the role of Treg cells in bladder autoimmune infammation. To facilitate Treg cell analysis, we further developed URO-OVA^GFP-Foxp3/OT-II mice, a derived line of URO-OVA/OT-II mice that express the green fuorescent protein （GFP）-forkhead box protein P3 （Foxp3） fusion protein. RESULTS： URO-OVA/OT-II mice failed to develop bladder infammation despite the presence of autoreactive CD4^＋ T cells. By monitoring GFP-positive cells, bladder infltration of CD4^＋ Treg cells was observed in URO-OVA^GFP-Foxp3/OT-II mice. The infiltrating Treg cells were functionally active and expressed Treg cell effector molecule as well as marker mRNAs including transforming growth factor-β, interleukin （IL）-10, fibrinogen-like protein 2, and glucocorticoid-induced tumor necrosis factor receptor （GITR）. Studies further revealed that Treg cells from URO-OVA^GFP-Foxp3/OT-II mice were suppressive and inhibited autoreactive CD4^＋ T cell proliferation and interferon （IFN）-g production in response to OVA Ag stimulation. Depletion of GITR-positive cells led to spontaneous development of bladder infammation and expression of inflammatory factor mRNAs for IFN-γ, IL-6, tumor necrosis factor-α and nerve growth factor in URO-OVA^GFP-Foxp3/OT-II mice. CONCLUSION： Treg cells specifc for bladder epithelial Ag play an important role in immunological homeostasis and the control of CD4^＋ T cell-mediated bladder autoimmune infammation.

Distinct toll-like receptor expression in monocytes and T cells in chronic HCV infection

AIM： Hepatitis C virus often establishes chronic infections. Recent studies suggest that viral and bacterial infections are more common in HCV-infected patients compared to controls. Pathogens are recognized by Toll-like receptors （TLRs） to shape adaptive and innate immune responses. METHODS： In this study, to infected host to recognize assess the ability of HCV-infected host to recognize invading pathogens, we investigated Toll-like receptor expression in innate （monocytes） and adaptive （T cells） immune cells by realtime PCR. RESULTS： We determined that RNA levels for TLRs 2, 6. 7, 8, 9 and 10 mRNA levels were upregulated in both monocytes and T cells in HCV-infected patients compared to controls. TLR4 was only upregulated in T lymphocytes, while TLR5 was selectively increased in monocytes of HCV-infected patients. MD-2, a TLR4 coreceptor, was increased in patients＇ monocytes and T cells while CD14 and MyD88 were increased only in monocytes. CONCLUSION： Our data reveal novel details on TLR expression that likely relates to innate recognition of pathogens and immune defense in HCV-infected individuals.

Uric acid enhances T cell immune responses to hepatitis B surface antigen-pulsed-dendritic cells in mice

AIM： To study the induction of T cellular immune responses in BALB/c mice immunized with uric acid and dendritic cells （DCs） pulsed with hepatitis B virus surface antigen （HBsAg）. METHODS： DCs were generated from bone-marrow cells of BABL/c mice, and then pulsed or unpulsed with HBsAg protein （HBsAg-pulsed-DCs or unpulsed-DCs） in vitro. BABL/c mice were immunized with HBsAg-pulsed- DCs （1 × 10^6） and uric acid, injected through the tail vein of each mouse. The mice in control groups were immunized with HBsAg-pulsed-DCs alone, unpulsed- DCs alone or 200 μg uric acid alone or PBS alone. The immunization was repeated 7 d later. Cytotoxic T lymphocytes （CTLs） in vivo were determined by the CFSE labeled spleen lysis assay. Spleen cells or spleen T cells were isolated, and re-stimulated in vitro with HBsAg for 120 h or 72 h. Production of IFN-γ, and IL-4 secreted by spleen cells were determined by ELISA method; proliferation of spleen T cells were detected by flow cytometry. RESULTS： The cytotoxicities of HBsAg-specific-CTLs, generated after immunization of HBsAg-pulsed-DCs and uric acid, were 68.63% ±11.32% and significantly stronger than that in the control groups （P 〈 0.01）. Compared with control groups, in mice treated with uric acid and HBsAg-pulsed-DCs, the spleen T cell proliferation to HBsAg re-stimulation was stronger （1.34 ± 0.093 vs 1.081±0.028, P 〈 0.01）, the level of IFN-t, secreted by splenocytes was higher （266.575 ± 51.323 vs 135.223 ±32.563, P 〈 0.01） , and IL-4 level wasower （22.385 ± 2.252 vs 40.598 ± 4.218, P 〈 0.01）. CONCLUSION： Uric acid can strongly enhance T cell immune responses induced by HBsAg-pulsed-DCs vaccine. Uric acid may serve as an effective adjuvant of DC vaccine against HBV infection.