NK cell transfer overcomes resistance to PD-(L)1 therapy in aged mice.

BACKGROUND: Cancer is the leading cause of death among older adults. Although the integration of immunotherapy has revolutionized the therapeutic landscape of cancer, the complex interactions between age and immunotherapy efficacy remain incompletely defined. Here, we aimed to elucidate the relationship between aging and immunotherapy resistance. METHODS: Flow cytometry was performed to evaluate the infiltration of immune cells in the tumor microenvironment (TME). In vivo T cell proliferation, cytotoxicity and migration assays were performed to evaluate the antitumor capacity of tumor antigen-specific CD8+ T cells in mice. Real-time quantitative PCR (qPCR) was used to investigate the expression of IFN-γ-associated gene and natural killer (NK)-associated chemokine. Adoptive NK cell transfer was adopted to evaluate the effects of NK cells from young mice in overcoming the immunotherapy resistance of aged mice. RESULTS: We found that elderly patients with advanced non-small cell lung cancer (aNSCLC) aged ≥ 75 years exhibited poorer progression-free survival (PFS), overall survival (OS) and a lower clinical response rate after immunotherapy. Mechanistically, we showed that the infiltration of NK cells was significantly reduced in aged mice compared to younger mice. Furthermore, the aged NK cells could also suppress the activation of tumor antigen-specific CD8+ T cells by inhibiting the recruitment and activation of CD103+ dendritic cells (DCs). Adoptive transfer of NK cells from young mice to aged mice promoted TME remodeling, and reversed immunotherapy resistance. CONCLUSION: Our findings revealed the decreased sensitivity of elderly patients to immunotherapy, as well as in aged mice. This may be attributed to the reduction of NK cells in aged mice, which inhibits CD103+ DCs recruitment and its CD86 expression and ultimately leads to immunotherapy resistance.

Accelerated discovery of high-performance Al-Si-Mg-Sc casting alloys by integrating active learning with high-throughput CALPHAD calculations.

Scandium is the best alloying element to improve the mechanical properties of industrial Al-Si-Mg casting alloys. Most literature reports devote to exploring/designing optimal Sc additions in different commercial Al-Si-Mg casting alloys with well-defined compositions. However, no attempt to optimize the contents of Si, Mg, and Sc has been made due to the great challenge of simultaneous screening in high-dimensional composition space with limited experimental data. In this paper, a novel alloy design strategy was proposed and successfully applied to accelerate the discovery of hypoeutectic Al-Si-Mg-Sc casting alloys over high-dimensional composition space. Firstly, high-throughput CALculation of PHAse Diagrams (CALPHAD) solidification simulations of ocean of hypoeutectic Al-Si-Mg-Sc casting alloys over a wide composition range were performed to establish the quantitative relation 'composition-process-microstructure'. Secondly, the relation 'microstructure-mechanical properties' of Al-Si-Mg-Sc hypoeutectic casting alloys was acquired using the active learning technique supported by key experiments designed by CALPHAD and Bayesian optimization samplings. After a benchmark in A356-xSc alloys, such a strategy was utilized to design the high-performance hypoeutectic Al-xSi-yMg alloys with optimal Sc additions that were later experimentally validated. Finally, the present strategy was successfully extended to screen the optimal contents of Si, Mg, and Sc over high-dimensional hypoeutectic Al-xSi-yMg-zSc composition space. It is anticipated that the proposed strategy integrating active learning with high-throughput CALPHAD simulations and key experiments should be generally applicable to the efficient design of high-performance multi-component materials over high-dimensional composition space.

Enhanced recovery after surgery (ERAS) protocol in geriatric patients underwent unicompartmental knee arthroplasty: A retrospective cohort study.

The enhanced recovery after surgery (ERAS) pathway was formulated with the aim to reduce surgical stress response, alleviate pain and guarantee the best-fit experience of patients' perioperative period. However, the application of ERAS in geriatric patients who underwent unicompartmental knee arthroplasty (UKA) was relatively lacking. We hypothesize that UKA patients can benefit from the ERAS protocol. A total of 238 patients were recruited in this retrospective study from August 2018 to December 2021, and Oxford phase III UKA was applied to all patients. ERAS pathway included nutrition support, anesthesia mode, interoperative temperature, and blood pressure control, application of tranexamic acid, early initiation of oral intake and mobilization, and pain management. Demographic data, operation-relative variables, and postoperative complications were analyzed. Forgotten Joint Scores, Oxford Knee Score, Lysholm score, numerical rating scale, and knee range of motion were introduced to estimate the activity function and pain of surgical knee, and these variables were compared between the 2 groups. There were 117 patients in the ERAS group and 121 patients in the traditional group, respectively. The ERAS group had a shorter length of surgical incision and less intraoperative blood loss. Postoperative hemoglobin and albumin of patients in the ERAS group were better than those in the traditional group (P < .05), after 17.0 ± 10.8 months follow-up, the numerical rating scale, Lysholm, Oxford Knee Score, Forgotten Joint Scores, and knee range of motion of patients in the ERAS group were significantly better than the traditional group. The length of hospital stay for patients who underwent ERAS was 11.7 ± 3.8 days and the postoperative complication rate was lower for the ERAS group patients (P = .000 and 0.031). ERAS can reduce the length of hospital stay, and patients can achieve excellent postoperative knee function. The formulation and implementation of the ERAS protocol require good collaboration across multiple disciplines, as well as a deep understanding of the existing clinical evidence and the concept of the ERAS program.

CD200+ cytotoxic T lymphocytes in the tumor microenvironment are crucial for efficacious anti-PD-1/PD-L1 therapy.

Anti-PD-1/PD-L1 therapy, either by anti-PD-1 antibody or anti-PD-L1 antibody, has efficacy by reinvigorating tumor-infiltrating CD8+ T cells in a subset of patients with cancer, but it has unequal effects on heterogeneous CD8+ T cell populations. Hence, the subset crucial to efficacious PD-1 blockade therapy remains elusive. Here, we found an increase in tumor-infiltrating CD200+ cytotoxic T lymphocytes (CTLs) upon PD-1/PD-L1 blockade, with higher proportions of CD200+ T cells positively related to a favorable clinical outcome to anti-PD-1/PD-L1 therapy in three independent cohorts of patients with cancer. Using multiple mouse tumor models, we demonstrated that CD200+ CTLs are essential for efficacious anti-PD-L1 therapy. Mechanistically, we observed a unique chromatin landscape in CD200+ CTLs and found that these cells are enriched for tumor antigen-specific CTLs and have antitumor effector functions. Coinoculation of CD200+ CTLs with tumor cells led to robust tumor regression in two transplanted mouse models. Clinically, we found that infiltration of CD200+ CTLs into tumors could predict immunotherapy efficacy in six patient cohorts. Together, our findings reveal that CD200+ CTLs in the tumor microenvironment are crucial for efficacious anti-PD-1/PD-L1 therapy and could serve as a predictor of successful immunotherapy in the clinic.

Computer Alloy Design of Ti Modified Al-Si-Mg-Sr Casting Alloys for Achieving Simultaneous Enhancement in Strength and Ductility.

In this paper, an efficient design of a Ti-modified Al-Si-Mg-Sr casting alloy with simultaneously enhanced strength and ductility was achieved by integrating computational thermodynamics, machine learning, and key experiments within the Bayesian optimization framework. Firstly, a self-consistent Al-Si-Mg-Sr-Ti quinary thermodynamic database was established by the calculation of phase diagram method and verified by key experiments. Based on the established thermodynamic database, a high-throughput Scheil-Gulliver solidification simulation of the A356-0.005Sr alloy with different Ti contents was carried out to establish the "composition-microstructure" quantitative relationship of the alloy. Then, by combining the computational thermodynamic, machine learning, and experimental data within the Bayesian optimization framework, the relationship "composition/processing-microstructure-properties" of A356-0.005Sr with different Ti contents was constructed and validated by the key experiments. Furthermore, the optimum alloy composition of the Ti-modified A356-0.005Sr casting alloy was designed based on this integration method with the Bayesian optimization framework and verified by the experiments. It is anticipated that the present integration method may serve as a general one for the efficient design of casting alloys, especially in the high-dimensional composition space.

C3a-C3aR signaling promotes breast cancer lung metastasis via modulating carcinoma associated fibroblasts.

BACKGROUND: Mounting evidence suggests that complement components promote tumor progression via modulating immune suppression, angiogenesis, or tumor cell proliferation. However, the role of C3a-C3aR signaling in regulating lung metastasis of breast cancer remains unknown. METHODS: We performed various ex-vivo and in-vivo assays. Genetic and pharmacological C3aR blockade models were applied to investigate the role of C3a-C3aR in metastasis of breast cancer. RESULTS: C3a-C3aR signaling in CAFs facilitates the metastasis of breast cancer. Mechanically, C3a-C3aR signaling augments pro-metastatic cytokine secretion and extracellular matrix components expression of CAFs via the activation of PI3K-AKT signaling. Genetic or pharmacological blockade of C3aR signaling effectively inhibited lung metastasis of breast cancer in mouse models. CONCLUSIONS: C3a-C3aR signaling in CAFs facilitates the metastasis of breast cancer. Targeting C3aR signaling is a potential anti-metastasis strategy for breast cancer therapy.

The histone methyltransferase EZH2 primes the early differentiation of follicular helper T cells during acute viral infection.

Epigenetic modifications to histones dictate the differentiation of naïve CD4+ T cells into different subsets of effector T helper (TH) cells. The histone methyltransferase enhancer of zeste homolog 2 (EZH2) has been implicated in the mechanism regulating the differentiation of TH1, TH2 and regulatory T (Treg) cells. However, whether and how EZH2 regulates follicular helper T (TFH) cell differentiation remain unknown. Using a mouse model of acute lymphocytic choriomeningitis virus (LCMV) infection, we observed abundant EZH2 expression and associated H3K27me3 modifications preferentially in the early committed virus-specific TFH cells compared to those in TH1 cells. Ablation of EZH2 in LCMV-specific CD4+ T cells leads to a selective impairment of early TFH cell fate commitment, but not late TFH differentiation or memory TFH maintenance. Mechanistically, EZH2 specifically stabilizes the chromatin accessibility of a cluster of genes that are important for TFH fate commitment, particularly B cell lymphoma 6 (Bcl6), and thus directs TFH cell commitment. Therefore, we identified the chromatin-modifying enzyme EZH2 as a novel regulator of early TFH differentiation during acute viral infection.

Impaired Cytolytic Activity and Loss of Clonal Neoantigens in Elderly Patients With Lung Adenocarcinoma.

INTRODUCTION: Whether the efficacy of programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors declines with senescence remains controversial for lung adenocarcinoma (LUAD). Responsiveness to anti-PD-1/PD-L1 therapy is thought to rely on neoantigen exposure and immune elements in the tumor microenvironment. In this study, we explored the features of the tumor immune microenvironment in elderly patients with treatment-naïve LUAD. METHODS: Transcriptome profiles and clinical characteristics of patients with LUAD were retrieved from The Cancer Genome Atlas as a discovery cohort. Immune cell infiltration (quantified by a single-sample gene set enrichment analysis), immunoregulatory molecule expression, and mutational patterns (from The Cancer Immunome Atlas) were compared between young and elderly patients. Immune cell infiltration was verified by immunohistochemistry using a validation cohort including 105 treatment-naïve patients with LUAD. A tissue microarray consisting of 120 LUAD patients was used in the immunohistochemistry validation. RESULTS: Activated CD8+ T cell numbers increased slightly with age, but cytolytic molecules in T cells (granzyme B [GZMB], perforin 1 [PRF1], granzyme A [GZMA], granzyme M [GZMM], and granulysin [GNLY]) gradually declined. PD-L1 expression was not associated with age; however, a number of immunosuppressive elements beyond PD-L1 were upregulated in aging patients, including regulatory T cells and co-inhibitory molecules, for example, TIM-3, TIGIT, and HHLA2. Finally, senescence was accompanied by a loss of clonal neoantigens, which is believed to be correlated with responsiveness to immune checkpoint inhibitors. CONCLUSIONS: Elderly patients were characterized by increased numbers of CD8+ T cells and impaired cytolytic molecule expression. The observed immune signature was also associated with a loss of clonal neoantigens and the accumulation of immunosuppressive elements. These findings show a unique immune microenvironment in senescence and support biomarker-guided candidate identification for anti-PD-1/PD-L1 therapeutic strategies for elderly patients with LUAD.

Intracellular Activation of Complement C3 Leads to PD-L1 Antibody Treatment Resistance by Modulating Tumor-Associated Macrophages.

Complement aids in the construction of an immunosuppressive tumor microenvironment. Tumor cell-derived C3 has been previously reported, but whether and how it acts on antitumor immunity remains to be elucidated. Here, we describe a mechanism for tumor cell-derived C3 in suppressing antitumor immunity. Tumor cell-derived C3 was activated intracellularly, which results in generation of C3a. C3a modulated tumor-associated macrophages via C3a-C3aR-PI3Kγ signaling, thereby repressing antitumor immunity. Deletion of C3 in tumor cells that had high C3 expression enhanced efficacy of anti-PD-L1 treatment. Collectively, our results suggest tumor cell-derived C3 may be a useful target for cancer immunotherapy and that targeting C3 in tumor cells may enhance antitumor immunity.

Centromere protein U expression promotes non-small-cell lung cancer cell proliferation through FOXM1 and predicts poor survival.

PURPOSE: Centromere protein U (CENPU) abnormally exhibits high expression in various types of human tumor tissues and participates in tumor progression; however, its expression pattern and biological function in lung cancer have not yet been elucidated. In the present study, we explored the clinical significance and biological function of CENPU in lung cancer. MATERIALS AND METHODS: The Cancer Genome Atlas (TCGA) data analyses, quantitative real-time PCR (RT-PCR), and Western blotting were performed to quantify CENPU and FOXM1 expression in non-small-cell lung cancer (NSCLC) samples. Survival data were obtained from Kaplan-Meier plotter or PROGgene V2 prognostic database. The function of CENPU in lung cancer cell proliferation was determined using 5-ethynyl-2'-deoxyuridine (EdU), Cell Counting Kit-8 (CCK-8), and cell cycle assays, and the underlying mechanism was determined through bioinformatic analyses and validated by in vitro siRNA or plasmid transfection experiments. RESULTS: CENPU was abnormally overexpressed in NSCLC samples compared with matched paired normal tissues. Higher expression of CENPU predicted worse overall survival (OS) and relapse-free survival (RFS) in NSCLC patients. Knockdown of CENPU expression by siRNA significantly inhibited proliferation and delayed cell cycle progression of lung cancer cells. To figure out the mechanism, bioinformatic analyses were performed and the results showed that the transcription factor, FOXM1, positively correlated with CENPU. Further in vitro experiments indicated that FOXM1 was the possible downstream transcription factor of CENPU as the knockdown of CENPU led to lower expression of FOXM1 and the overexpression of FOXM1 significantly reversed the inhibition of proliferation caused by CENPU knockdown. Furthermore, FOXM1 was highly expressed in NSCLC. The knockdown of FOXM1 also attenuated proliferation and induced G1 arrest in lung cancer cells. CONCLUSION: CENPU was highly expressed in NSCLC tissues, wherein it promoted lung cancer cell proliferation via the transcription factor, FOXM1, which could be a potential target for therapeutic strategies.

Late-stage tumors induce anemia and immunosuppressive extramedullary erythroid progenitor cells.

Impaired immunity in patients with late-stage cancer is not limited to antitumor responses, as demonstrated by poor vaccination protection and high susceptibility to infection1-3. This has been largely attributed to chemotherapy-induced impairment of innate immunity, such as neutropenia2, whereas systemic effects of tumors on hematopoiesis and adoptive immunity remain incompletely understood. Here we observed anemia associated with severe deficiency of CD8+ T cell responses against pathogens in treatment-naive mice bearing large tumors. Specifically, we identify CD45+ erythroid progenitor cells (CD71+TER119+; EPCs) as robust immunosuppressors. CD45+ EPCs, induced by tumor growth-associated extramedullary hematopoiesis, accumulate in the spleen to become a major population, outnumbering regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). The CD45+ EPC transcriptome closely resembles that of MDSCs, and, like MDSCs, reactive oxygen species production is a major mechanism underlying CD45+ EPC-mediated immunosuppression. Similarly, an immunosuppressive CD45+ EPC population was detected in patients with cancer who have anemia. These findings identify a major population of immunosuppressive cells that likely contributes to the impaired T cell responses commonly observed in patients with advanced cancer.

Cytotoxic chemotherapy reduces T cell trafficking to the spleen by downregulating the expression of C-C motif chemokine ligand 21 and C-C motif chemokine ligand 19.

T cells serve an important role in the destruction of tumor cells and clearing of foreign pathogens. Previous studies have suggested that the T cell immune response of tumor-bearing patients is significantly lower than that of healthy people, and the principal reason for this is lymphocytopenia, which is caused by repeated cycles of chemotherapy. In addition to lymphocytopenia, the present study revealed that cytotoxic chemotherapy also weakens the homing ability of T cells to the T-cell zone of the spleen, which decreases the possibility of encounters between antigen-specific T cells and dendritic cells presenting the appropriate antigen, thereby weakening the immune response of T cells. These changes are attributed to the lower expression of C-C motif chemokine ligand 21 (CCL21) and C-C motif chemokine ligand 19 (CCL19) in the spleen of secondary lymphoid organs (SLOs). Finally, the present study identified that chemotherapy affects the function and survival of fibroblastic reticular cells in SLOs, which are the main source of CCL21 and CCL19. These observations aid us in further understanding the mechanism that is responsible for the decreased T cell immune response following repeated cycles of chemotherapy.

Disrupted fibroblastic reticular cells and interleukin-7 expression in tumor draining lymph nodes.

The immune system of patients with cancer is usually in an inhibitory state. Lymph node (LN) draining of pathological sites provides a suitable microenvironment where adaptive immune responses mainly occur. However, the microenvironment in the tumor draining lymph nodes (TDLNs) of patients with cancer appears to be in favor of tolerance. The effects of tumor cells on TDLNs have not been elaborated clearly. The present results have indicated that tumor cells may directly affect TDLNs by decreasing the fibroblastic reticular cell population that led to less interleukin-7 secretion. As a result, the number of T cells in TDLNs declined with reduced survival signals. A decreased number of T cells in TDLNs means weakened ability of immune surveillance. Clinically, these results were also confirmed in LN biopsies from patients with colon cancer at different clinical stages. Results of the present study showed that tumor cells may directly inhibit the immunological function of TDLNs.

Disrupted Homeostatic Cytokines Expression in Secondary Lymph Organs during HIV Infection.

Research has firmly established that infection by human immunodeficiency virus (HIV) leads to structural disruption in secondary lymph organs (SLOs) and that IL-7 expression by SLOs is downregulated in simian immunodeficiency virus (SIV)-infected rhesus macaques. However, the foregoing has not been demonstrated in HIV-infected patients. As well, SLO-produced chemokines and cytokines, other than IL-7, have not been tested. In this study, SLOs in HIV-infected patients exhibit decreased levels of lymphoid cytokines, such as IL-7 and C-C motif chemokine ligand 21 (CCL21), due to lower expression of lymphotoxin (LT)-ß. Previous research has shown that LT-ß is produced mainly by CD4⁺T cells in rhesus macaques, while our study found the same level of LT-ß expressed by CD4⁺T and CD8⁺T cells in humans. CD8⁺T cells substitute for depleted CD4⁺T cells LT-ß production. Only the total number of CD3⁺T cells can account for the majority of LT-ß in human SLOs. This study indicates a possible mechanism and a potential target for improvement of SLO function in HIV-infected patients, a novel adjuvant therapy for AIDS.

Mechanism of Action of IL-7 and Its Potential Applications and Limitations in Cancer Immunotherapy.

Interleukin-7 (IL-7) is a non-hematopoietic cell-derived cytokine with a central role in the adaptive immune system. It promotes lymphocyte development in the thymus and maintains survival of naive and memory T cell homeostasis in the periphery. Moreover, it is important for the organogenesis of lymph nodes (LN) and for the maintenance of activated T cells recruited into the secondary lymphoid organs (SLOs). The immune capacity of cancer patients is suppressed that is characterized by lower T cell counts, less effector immune cells infiltration, higher levels of exhausted effector cells and higher levels of immunosuppressive cytokines, such as transforming growth factor ß (TGF-ß). Recombinant human IL-7 (rhIL-7) is an ideal solution for the immune reconstitution of lymphopenia patients by promoting peripheral T cell expansion. Furthermore, it can antagonize the immunosuppressive network. In animal models, IL-7 has been proven to prolong the survival of tumor-bearing hosts. In this review, we will focus on the mechanism of action and applications of IL-7 in cancer immunotherapy and the potential restrictions for its usage.

Essential role of TNF-alpha in development of spleen fibroblastic reticular cells.

TNF-alpha plays an important role in the development of secondary lymphoid tissues. Earlier studies showed that fibroblastic reticular cells express TNF-alpha receptor, suggesting that TNF-alpha may affect the development of FRCs. To test this, we analyzed the development and function of FRCs in wild-type or TNF-alpha knockout mice. We found that GP38 expression was down-regulated in the spleen of TNF-alpha knockout mice. Chemokines, mainly secreted by GP38(+) FRCs, were also down-regulated. Additionally, we found that absence of TNF-alpha decreased the homing ability to direct T cells to the spleen. However, absence of TNF-alpha did not affect the development of lymph nodes FRCs. These data reveal that TNF-alpha plays an important role in the development of spleen FRCs. Absence of TNF-alpha could cause abnormality of spleen FRCs, thereby weakening the homing ability of T cells to localize to the spleen T cell zone.

T lymphocytes maintain structure and function of fibroblastic reticular cells via lymphotoxin (LT)-B.

BACKGROUND: Although a lot is known about how Fibroblastic Reticular Cells (FRCs) can regulate T lymphocytes (T cells), little is understood about whether or how T cells can regulate FRCs. RESULTS: This study shows that the absence of T cells inhibited the secretion of ER-TR7 by splenic FRCs, induced the structural disorder of FRCs, down-regulated the expression of the chemokine ligands CCL21 and CCL19, and weakened the homing ability of T cells to the spleen of nude mice. Transfusion of T cells from BALB/c mice restored the structure and functions of FRCs and recovered them. The expression of lymphotoxin (LT)-B was significantly downregulated in the absence of T cells from nude mice and was recovered after the transfusion of T cells. After the occlusion of the LT-B receptor, the FRCs' structure and functions were not restored by transfusion of T cells. CONCLUSIONS: These data reveal that the absence of T cells will subject spleen FRCs to structural and functional abnormality, and weaken the homing ability of T cells to the spleen. These changes are attributed to the T-cell- derived LT-B.

[Adsorption and desorption of Bt toxin on three kinds of minerals].

This paper studied the characteristics of the adsorption and desorption of Bt (Bacillus thuringiensis) toxin on goethite, kaolinite, and silica. The results showed that in phosphate buffer (pH 8), the adsorption isotherms of Bt toxin on the test minerals followed Langmuir equation (R2 >0. 9661), and the adsorbed amounts were in the order of goethite > kaolinite > silica. The Bt toxin was easily adsorbed on the minerals, and the adsorption could reach equilibrium after 1 hour. Within the range of pH 6-8, the amounts of Bt toxin adsorbed on goethite, kaolinite and silica decreased with increasing pH; in the range of 10 degrees C-50 degrees C, the amounts of the toxin adsorbed on goethite and silica decreased by 8.39% and 47.06%, respectively, while that on kaolinite increased slightly (5.91%). The infrared absorption spectrum showed that there was only a minor alteration of Bt toxin after adsorption. The toxin adsorbed on the minerals was not easily desorbed by deionised water, with the desorption rate ranged from 28.48% to 42.04% after three times washing.