Large-cohort humanized NPI mice reconstituted with CD34+ hematopoietic stem cells are feasible for evaluating preclinical cancer immunotherapy.

Cancer immunotherapy has achieved impressive therapeutic effects in many cancers, while only a small subset of patients benefit from it and some patients even have experienced severe toxicity. It is urgent to develop a feasible large-cohort humanized mouse model to evaluate the pre-clinical efficacy and safety of cancer immunotherapy. Furthermore, developing potentially effective combination therapy between cancer immunotherapy and other therapies also needs humanized mouse model to adequately mimic clinical actual setting. Herein, we established a humanized mouse model engrafted with less human CD34+ HSCs than ever before and then evaluated reconstitution efficiency and the profiles of human immune cells in this humanized mouse model. Also, this humanized mouse model was used to evaluate the preclinical efficacy and safety of cancer immunotherapy. For each batch of CD34+ HSCs humanized mouse model, a relatively-large cohort with over 25% human CD45+ cells in peripheral blood was established. This humanized mouse model could efficiently reconstitute human innate and adaptive immune cells. This humanized mouse model supported patient-derived xenograft tumor growth and tumor infiltration of PD-1+ human T cells. Furthermore, therapeutic efficacy, re-activation of tumor-infiltrated T cells, and side effects of checkpoint blockade therapy could be monitored in this humanized mouse model. Human T cells from this humanized mouse model were successfully engineered with CD19-CAR. CD19 CAR-T cells could effectively deplete B cells and suppress tumor growth of acute lymphoblastic leukemia in vivo in this humanized mouse model. This humanized mouse model also could be used to demonstrate the efficacy of bispecific antibodies, such as anti-CD19/CD3. Overall, our work provides a feasible large-cohort humanized mouse model for evaluating a variety of cancer immunotherapy approaches including checkpoint inhibitors, adoptive cell therapy, and bispecific antibody therapy, and demonstrates that human T cells from this humanized mouse model possess anti-tumor activities in vitro and in vivo.

Circulating CXCR5+CD4+ T cells assist in the survival and growth of primary diffuse large B cell lymphoma cells through interleukin 10 pathway.

Diffuse large B cell lymphoma (DLBCL) is a common and aggressive cancer caused by the malignant transformation of B cells. Although it has been established that the follicular helper T (Tfh) cells play a central role in B cell development, little information is available on their involvement in DLBCL pathogenesis. We studied the role of the peripheral Tfh equivalent, the CXCR5+ CD4+ T cells, in DLBCL. Data showed that compared to CXCR5- CD4+ T cells, CXCR5+ CD4+ T cells were significantly more effective at promoting the proliferation as well as inhibiting the apoptosis of primary autologous DLBCL tumor cells. Surprisingly, we found that at equal cell numbers, CXCR5+ CD4+ T cells in DLBCL patients secreted significantly less interleukin (IL)-21 than CXCR5- CD4+ T cells, while the level of IL-10 secretion was significant elevated in the CXCR5+ compartment compared to the CXCR5- compartment. Neutralization of IL-10 in the primary DLBCL-CXCR5+ CD4+ T cell coculture compromised the CXCR5+ CD4+ T cell-mediated pro-tumor effects, in a manner that was dependent on the concentration of anti-IL-10 antibodies. The CXCR5+ compartment also contained significantly lower frequencies of cytotoxic CD4+ T cells than the CXCR5- compartment. In conclusion, our investigations discovered a previously unknown pro-tumor role of CXCR5-expressing circulating CD4+ T cells, which assisted the survival and proliferation of primary DLBCL cells through IL-10.

Adaptive B cell responses in rituximab-treated diffuse large B cell lymphoma patients during complete remission.

Rituximab is a chimeric monoclonal antibody directed against the CD20 antigen. Treatment using rituximab in combination with chemotherapy has dramatically improved overall survival rate of diffuse large B cell lymphoma (DLBCL). Since rituximab can deplete both lymphoma B cells and normal B cells, how rituximab-treatment affects normal B cell function in DLBCL patients under remission is unclear. Here, we examined peripheral blood B cell composition and antigen-specific B cell responses in DLBCL patients in remission and observed reductions in the frequencies of total B cell as well as several major B cell subsets, including CD19(+)IgD(+) naive B cells, CD19(+)IgD(-)CD27(+) memory B cells, and CD19(lo)CD27(hi) plasmablasts. Moreover, tetanus toxin (TT)-specific B cell proliferation was reduced in DLBCL patients in remission. On the other hand, HA-specific IgG-secreting B cell responses could be stimulated by influenza vaccination in DLBCL patients in remission, demonstrating that the machinery for generating de novo adaptive B cell responses was functional in DLBCL patients in remission. Our results provided insights in normal B cell function in DLBCL patients in remission.

Alterations of circulating follicular helper T cells and interleukin 21 in diffuse large B-cell lymphoma.

CD4+ CXCR5+ T cell in peripheral blood is known as circulating follicular helper T cell (Tfh), which can produce interleukin 21 (IL-21). In the current study, we investigated changes of circulating Tfh and its correlation with IL-21 in diffuse large B-cell lymphoma (DLBCL). Circulating Tfh and its subtypes were detected by flow cytometry in the peripheral blood of 32 healthy donors and 62 DLBCL cases. Data demonstrated that percentage of circulating Tfh in CD4+ T cells was significantly increased in DLBCL (11.3 %) than in controls (8.5 %) (p = 0.001). Studying the subtypes of Tfh revealed that the upregulation of circulating Tfh was contributed by Tfh-Th2 subtype and Tfh-Th17 subtype. Also, we identified that prevalence of Tfh was significantly elevated in cases with advanced stages (stages III and IV). Interestingly, the elevation of circulating Tfh was negatively correlated with serum IL-21 in DLBCL patients. In addition, a positive correlation between circulating Tfh and IL-21 receptor on CD + 8 T cells was observed in patients. This study suggests involvement of circulating Tfh and IL-21 in the pathogenesis and progression of DLBCL and provides a potential target for treating this disease.

Fibroblast growth factor receptor 4 polymorphisms and the prognosis of non-Hodgkin lymphoma.

Fibroblast growth factors and their receptors (FGFRs) play important roles in blood system. FGFR4 rs351855 (Gly388Arg) polymorphism has shown to be a risk factor for many diseases. The aim of this study was to investigate the association between FGFR4 polymorphisms and the susceptibility to non-Hodgkin lymphoma (NHL) in the Chinese population. We identified two polymorphisms in the FGFR4 gene, rs351855G/A (Gly388Arg), and rs147603016G/A, by polymerase chain reaction-restriction fragment length polymorphism in 412 NHL cases and 476 healthy controls. Results showed that frequencies of AA genotype and A allele in rs351855 (Gly388Arg) polymorphism were significantly higher in patients than in controls (odds ratio (OR) 2.12, 95 % confidence intervals (CI) 1.99-3.48, P < 0.0001; OR 1.45, 95 % CI 1.21-1.88, P < 0.0001, respectively; data were adjusted for age and sex). The rs147603016G/A polymorphism did not show any correlation with NHL. When analyzing the survival time of NHL patients with FGFR4 rs351855G/A polymorphism, cases with AA genotype had significantly shorter survival time compared to the patients with GG and GA genotypes (P = 0.002). These results suggested polymorphism in FGFR4 gene was associated with increased susceptibility to NHL and could be used as a prognostic marker for this malignancy.

Association of peripheral CD4+ CXCR5+ T cells with chronic lymphocytic leukemia.

Accumulating evidences indicate that immune dysregulation plays a key role in both lymphomagenesis and patient outcome of chronic lymphocytic leukemia (CLL). Peripheral blood CD4+ CXCR5+ T cells, known as circulating follicular helper T cells (Tfh), can induce B cell activation and production of specific antibody responses. The aim of the study was to investigate changes of circulating Tfh in CLL. Tfh and it subtypes were tested by measuring CD4, CXCR5, CXCR3, and CCR6 in 72 CLL cases and 86 healthy controls using flow cytometry. Data showed that the percentage of Tfh in the peripheral CD4+ T cells was significantly increased in CLL (25.1%) than in controls (8.4%) (p < 0.001). Further analysis revealed that the upregulation of Tfh was contributed by Tfh-th2 subtype and Tfh-th17 subtype. Investigating staging of the cases demonstrated that the prevalence of Tfh was significantly elevated in cases with Binet stage C (37.3%) than those with stage A (20.1 %) or stage B (23.9 %). In addition, we analyzed Tfh in patients with immunoglobulin variable heavy chain (IGHV) gene mutational status. Results presented that Tfh-th17 subtype had clearly higher frequency in patients with IGHV mutation compared to the unmutated cases (p = 0.035). This study suggested the involvement of Tfh in the pathogenesis and progression of CLL, and provided a potential target for treating this disease.

C-X-C chemokine receptor type 5 gene polymorphisms are associated with non-Hodgkin lymphoma.

The C-X-C chemokine receptor type 5 (CXCR5) is one of the principal regulators for targeting T cells, B cells and dendritic cells into secondary lymphoid organs. Polymorphism studies of CXCR5 gene remain extremely scarce. The aim of this study was to examine the effect of polymorphisms in the CXCR5 gene on the development of non-Hodgkin lymphoma (NHL) in the Chinese population. Four polymorphisms in CXCR5 gene, rs148351692C/G, rs6421571C/T, rs80202369G/A and rs78440425G/A, were tested by polymerase chain reaction-restriction fragment length polymorphism in 404 NHL cases and 456 age-matched healthy controls. Data were analyzed using the χ(2) test. Results showed that individuals with the rs6421571 CT, rs6421571 TT and rs80202369 AA genotype had significantly increased susceptibility to NHL [Odd ratio (OR) = 1.41, 95 % confidence interval (CI): 1.04-1.92, p = 0.028; OR = 2.30, 95 % CI: 1.44-3.65, p < 0.001; and OR = 3.24, 95 % CI: 1.26-8.32, p = 0.010, respectively]. When analyzing the haplotypes of these polymorphisms, the prevalence of the TGG (rs6421571, rs80202369, and rs78440425) haplotype was significantly higher in NHL cases than in controls (OR = 1.59, 95 % CI: 1.25-2.03, p < 0.001). In addition, numbers of rs6421571 TT genotype and T allele were significantly increased in NHL patients with high Ann Arbor stages (p < 0.03) or NHL with B cell subtype (p < 0.02). These data indicate that CXCR5 gene polymorphisms may be new risk factors for NHL. The finding that the adjacent SNPs, rs6421571C/T and rs80202369G/A, are both associated with NHL suggests that the 87 bp region carrying these 2 polymorphisms may have important functional significance.

The prevalence and function of CD4+CXCR5+Foxp3+ follicular regulatory T cells in diffuse large B cell lymphoma.

CD4+CXCR5+Foxp3+ follicular regulatory T (Tfr) cells possess critical roles in suppressing the germinal center reaction, B cell activation, and follicular helper T cell (Tfh) cytokine secretion. Since diffuse large B cell lymphoma (DLBCL) can arise from B cells undergoing germinal center reaction and/or differentiation, we hypothesized that Tfr cells might be involved in DLBCL. In the present study, we recruited thirty-five DLBCL patients and twenty-five healthy controls. Data showed that DLBCL patients presented an enrichment of circulating CD4+CXCR5+Foxp3+ Tfr cells compared to controls. In the primary tumor isolated from enlarged lymph nodes, Tfr cells made up of roughly 3% to 16% of infiltrating T cells. Higher levels of tumor-infiltrating Tfr cells were observed in patients with less advanced DLBCL stages, and in patients that stayed in remission 24 months after the initial R-CHOP treatment. High BCL6 and high FOXP3 expression was observed in Tfr cells ex vivo. After anti-CD3/CD28 and IL-2 stimulation, the Tfr cells more closely resembled Treg cells and presented high IL10 and TGFB1 expression. CD4+CD25+CXCR5+ Tfr cells and CD4+CD25+CXCR5- non-Tfr Treg cells could suppress CD4+CD25- Tconv cell and CD8+ T cell proliferation with similar capacity. However, Tfr cells were less capable of suppressing IFNG expression than Treg cells, and although both cell types supported CD19+ tumor cell proliferation, Tfr cells were less supportive than the non-Tfr Treg cells. Overall, this study suggested that Tfr cells were involved in intratumoral immunity, were likely beneficial to DLBCL patients, and were functionally distinctive from non-Tfr Treg cells. The distribution pattern and the prognostic value of Tfr cells in DLBCL should be examined in further studies.

The prognostic potential and oncogenic effects of PRR11 expression in hilar cholangiocarcinoma.

PRR11 is a newly identified oncogene in lung cancer, yet its role in others tumors remains unclear. Gastrointestinal tissue microarrays were used to evaluate PRR11 expression and its association with clinical outcome was analyzed in patients with hilar cholangiocarcinoma. Overexpression of PRR11 was observed in esophageal, gastric, pancreatic, colorectal, and hilar cholangiocarcinoma. Expression of PRR11 correlated with lymph node metastasis and CA199 level in two HC patient cohorts. After an R0 resection, a high level of PRR11 expression was found to be an independent indicator of recurrence (P = 0.001). In cell culture, PRR11 silencing resulted in decreased cellular proliferation, cell migration, tumor growth of QBC939 cells. Microarray analysis revealed that several genes involved in cell proliferation, cell adhesion, and cell migration were altered in PRR11-knockout cells, including: vimentin (VIM), Ubiquitin carboxyl-terminal hydrolase 1 (UCHL1), early growth response protein (EGR1), and System A amino acid transporter1 (SNAT1). Silencing PRR11 inhibited the expression of UCHL1, EGR1, and SNAT1 proteins, with immunoassays revealing a significant correlation among the levels of these four proteins. These results indicate that PRR11 is an independent prognostic indicator for patients with HC.

Dysregulation of circulating follicular helper T cells in nonsmall cell lung cancer.

Nonsmall cell lung cancer (NSCLC) is greatly affected by the dysregulation of the immune system. Circulating follicular helper T cells (Tfh) play critical roles in inducing B-cell activation and producing various cytokines. In the current study, we investigated levels of circulating Tfh in NSCLC. Circulating Tfh and it subtypes were determined by measuring CD3, CD4, CXCR5, CXCR3, and CCR6 in 62 NSCLC patients and 66 healthy controls using flow cytometry. Data presented that percentage of circulating Tfh in the peripheral CD4(+) T cells was significantly increased in NSCLC (14.0%) than in controls (8.7%) (p<0.001). Further analysis revealed that the upregulation of Tfh was contributed by the Th2-Tfh subtype and the Th17-Tfh subtype, whereas the percentage of the Th1-Tfh subtype was significantly decreased in patients. Investigating the clinical stages of the patients demonstrated that prevalence of Tfh was significantly elevated in cases with advanced stages (III: 14.2%; IV: 16.4%) than those with primary stages (I: 10.9%; II: 10.8%). In addition, we analyzed Tfh in patients with different histological types. Results showed that the percentage of circulating Tfh was further upregulated in adenocarcima than squamous cell carcinoma or other types. This study suggests the involvement of circulating Tfh in the pathogenesis and progression of NSCLC, and provides a potential pathway for understanding this disease.

Effect of interleukin 21 and its receptor on CD8+ T cells in the pathogenesis of diffuse large B-cell lymphoma.

Interleukin 21 (IL-21) and its receptor, IL-21R, play a key role in innate and adaptive immunity. In the present study, the effect of IL-21 and IL-21R on the pathogenesis of diffuse large B-cell lymphoma (DLBCL) was investigated. The serum levels of IL-21 were detected by enzyme-linked immunosorbent assay, and the expression of IL-21R on CD8+ T cells was examined through flow cytometry. The data showed that the serum level of IL-21 was significantly decreased in the patients with DLBCL compared with the healthy controls (P<0.001), whereas the expression of IL-21R was clearly elevated on the CD8+ T cells in the patients with DLBCL. Further analyses revealed that the downregulation of the IL-21 serum level was correlated with an increased tumor stage of DLBCL, while the expression of IL-21R on the CD8+ T cells was positively correlated with the tumor stage. Also, the serum level of IL-21 and the proportion of IL-21R on the CD8+ T cells were negatively correlated in the patients. Notably, it was identified that the proportion of IL-21R on the CD8+ T cells, but not the serum level of IL-21, was significantly upregulated in the patients with bone-marrow involvement and B symptoms. These results indicate that IL-21 and IL-21R may be involved in the pathogenesis of DLBCL, in which IL-21R may reflect the progression of the disease more accurately than the serum level of IL-21.

Mycobacterium leprae upregulates IRGM expression in monocytes and monocyte-derived macrophages.

Leprosy is caused by the infection of Mycobacterium leprae, which evokes a strong inflammatory response and leads to nerve damage. Immunity-related GTPase family M protein (IRGM) plays critical roles in controlling inflammation. The objective of the study was to investigate whether IRGM is involved in the infection of M. leprae. Levels of IRGM were assessed in M. leprae-infected CD4(+) T cells, monocytes, and monocyte-derived macrophages. Data revealed that both protein and mRNA levels of IRGM were increased in monocytes after M. leprae infection. Interestingly, monocyte-derived macrophages showed more prominent IRGM expression with M. leprae infection, whereas the bacteria did not affect IRGM in CD4(+) T cells. Furthermore, we assessed levels of IRGM in CD4(+) T cells and monocytes from 78 leprosy patients and 40 healthy controls, and observed upregulated protein level of IRGM in the monocytes from leprosy patients. Also, IRGM expression was inversely correlated with the severity of the disease. These findings suggested a close involvement of IRGM in M. leprae infection and indicated a potential mechanism of defending M. leprae infection.

T-cell immunoglobulin- and mucin-domain-containing molecule 3 genetic variants and HIV+ non-Hodgkin lymphomas.

T cell immunoglobulin- and mucin-domain-containing molecule 3 (TIM-3) has been established as a negative regulatory molecule and plays a critical role in inflammatory diseases such as rheumatoid arthritis, hepatitis B and C, and human immunodeficiency virus (HIV)-related inflammation. Recent studies have shown that chronic inflammation may greatly affect the pathogenesis of non-Hodgkin lymphomas (NHL). The aim of this study was to investigate whether polymorphisms in the TIM-3 gene were associated with susceptibility to non-NHL and HIV-related NHL. Three polymorphisms in TIM-3 gene (-1516G/T, -574G/T, and +4259T/G) were identified by polymerase chain reaction-restriction fragment length polymorphism in 434 NHL patients, 62 HIV-related NHL cases, and 512 healthy controls. Results showed that the prevalence of -574GT genotype and +4259TG genotype were significantly increased in the NHL cases than in controls (odds ratio (OR) = 2.72, 95% confidence interval (CI) = 1.50-4.92, p = 0.0006 and OR = 2.59, 95% CI = 1.49-4.49, p = 0.0005, respectively). The -1516G/T polymorphism did not reveal significant difference between patients and healthy controls. When analyzing the TIM-3 polymorphisms in HIV-related NHL patients, data showed that HIV+ NHL patients had higher prevalence of -574GT or +4259TG genotypes than those cases without HIV infection (OR = 3.48, 95% CI = 1.67-7.28, p = 0.0005 and OR = 2.92, 95% CI = 1.42-6.01, p = 0.0026, respectively). These results suggested polymorphisms in TIM-3 gene could be new risk factors for NHL as well as HIV-related NHL and suggested a possible role of the inflammatory factor in these diseases.

Interleukin 2 gene polymorphisms are associated with non-Hodgkin lymphoma.

Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy worldwide. Interleukin-2 (IL-2) plays a key role in the proliferation of T cells and natural killer cells. It has been reported that polymorphisms in the IL-2 gene are associated with various cancers. The aim of this study was to examine the effect of polymorphisms in the IL-2 gene on the development of NHL in the Chinese population. IL-2-330T/G and +114T/G polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism in 438 NHL cases and 482 age-matched healthy controls. Data were analyzed using the Chi-square test. Results showed that individuals with -330TG genotype or -330GG genotype had significantly increased susceptibility to NHL (Odds ratio [OR] = 1.40, 95% confidence interval [CI]: 1.05-1.85, p = 0.020 and OR = 2.04, 95%CI: 1.28-3.24, p = 0.002). Meanwhile, the +114T/G polymorphism did not show any correlation with NHL. When analyzing the haplotypes of these two polymorphisms, the prevalence of -330G/+114T haplotype was significantly higher in NHL cases than in controls (OR = 1.45, 95%CI: 1.12-1.88, p = 0.005). These data indicate that IL-2 gene polymorphisms may be new risk factors for NHL.