A Nomogram to Predict Pathological Axillary Status in Breast Cancer Patients Treated with Neoadjuvant Chemotherapy

PURPOSE/OBJECTIVE(S)

This study aimed to identify factors influencing axillary pathological complete response (pCR) and to develop a predictive nomogram to evaluate axillary pCR rate in breast cancer patients treated with neoadjuvant chemotherapy (NAC).

MATERIALS/METHODS

A total of 2368 patients who received NAC and mastectomy between 2000 and 2014 from 12 grade A tertiary hospitals in China were analyzed retrospectively. The patients treated in three cancer hospitals (training set, n = 1629) were used to construct the nomogram based on multivariate logistic regression analyses. The nomograph was validated by the area under the receiver operating characteristic curve (AUC) and calibration curve in patients from 9 other general hospitals (validation set, n = 739).

RESULTS

The nomogram incorporated seven predicting factors including NACT cycles, response to NACT, clinical T stage, clinical N stage, grade, LVI, and molecular subtype. The AUC for the training set and validation set were 0.762 and 0.802, respectively. In addition, the calibration curve also showed good agreement between the nomogram-based predictions and the actual observations.

CONCLUSION

A nomogram was established to predict the status of axillary lymph nodes in breast cancer patients after NAC. The predictive model performed well both in the training set and external validation set.

Retinoic acid signaling during priming licenses intestinal CD103+ CD8 TRM cell differentiation

CD8 tissue-resident memory T (TRM) cells provide frontline protection at barrier tissues; however, mechanisms regulating TRM cell development are not completely understood. Priming dictates the migration of effector T cells to the tissue, while factors in the tissue induce in situ TRM cell differentiation. Whether priming also regulates in situ TRM cell differentiation uncoupled from migration is unclear. Here, we demonstrate that T cell priming in the mesenteric lymph nodes (MLN) regulates CD103+ TRM cell differentiation in the intestine. In contrast, T cells primed in the spleen were impaired in the ability to differentiate into CD103+ TRM cells after entry into the intestine. MLN priming initiated a CD103+ TRM cell gene signature and licensed rapid CD103+ TRM cell differentiation in response to factors in the intestine. Licensing was regulated by retinoic acid signaling and primarily driven by factors other than CCR9 expression and CCR9-mediated gut homing. Thus, the MLN is specialized to promote intestinal CD103+ CD8 TRM cell development by licensing in situ differentiation.

Deep learning for predicting the risk of immune checkpoint inhibitor-related pneumonitis in lung cancer

AIM

To develop and validate a nomogram model that combines computed tomography (CT)-based radiological factors extracted from deep-learning and clinical factors for the early predictions of immune checkpoint inhibitor-related pneumonitis (ICI-P).

MATERIALS AND METHODS

Forty ICI-P patients and 101 patients without ICI-P were divided randomly into the training (n=113) and test (n=28) sets. The convolution neural network (CNN) algorithm was used to extract the CT-based radiological features of predictable ICI-P and calculated the CT score of each patient. A nomogram model to predict the risk of ICI-P was developed by logistic regression.

RESULTS

CT score was calculated from five radiological features extracted by the residual neural network-50-V2 with feature pyramid networks. Four predictors of ICI-P in the nomogram model included a clinical feature (pre-existing lung diseases), two serum markers (absolute lymphocyte count and lactate dehydrogenase), and a CT score. The area under curve of the nomogram model in the training (0.910 versus 0.871 versus 0.778) and test (0.900 versus 0.856 versus 0.869) sets was better than the radiological and clinical models. The nomogram model showed good consistency and better clinical practicability.

CONCLUSION

The nomogram model that combined CT-based radiological factors and clinical factors can be used as a new non-invasive tool for the early prediction of ICI-P in lung cancer patients after immunotherapy with low cost and low manual input.

Programmed Death of Microglia in Alzheimer's Disease: Autophagy, Ferroptosis, and Pyroptosis

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline, amyloid-β (Aβ) plaques and the formation of neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau. Increasing evidence has demonstrated that the damage of cell plays an important role in AD. Cell death is a critical phenomenon for physiological functions, which promotes AD pathogenesis. Programmed cell death, including necroptosis, pyroptosis, autophagy, and ferroptosis, have been discovered that have unique biological functions and pathophysiological characteristics. Here, we review the available evidence detailing the mechanisms of programmed microglial death, including pyroptosis, autophagy, and ferroptosis. We also highlight the role of programmed death of microglia during the process of AD and focus on the connection between the disease and cell death.

Comparison of Telomere Length between Buccal Cells and Blood Cells

Telomere length (TL) in blood cells is commonly used as a proxy for TL in other tissue types. The source of DNA of adequate quality and quantity is important for TL analysis. Compared to blood cells, buccal cells easy for genomic DNA preparation would facilitate the rapid and reliable TL analysis. However, the feasibility of buccal cells for TL analysis remains yet unestablished. We characterized TL of buccal cells and blood cells collected from 52 individuals using buccal cell swabs and fingertip sticks. Relative TL (RTL) determined by quantitative PCR showed that there is a strong correlation between buccal RTL and blood RTL (r=0.877, p<0.001), suggesting that buccal cells are adequate sources of DNA for TL analysis. The validity of sampling using buccal cell swabs provides simple operation and good reproducibility for TL analysis, that overcomes the discomfort and risk of infection caused by blood sampling.

The accumulation of Vγ4 T cells with aging is associated with an increased adaptive Vγ4 T cell response after foodborne Listeria monocytogenes infection of mice

BACKGROUND

It is generally accepted that aging has detrimental effects on conventional T cell responses to systemic infections. However, most pathogens naturally invade the body through mucosal barriers. Although mucosal sites are highly enriched in unconventional immune sentinels like γδ T cells, little is currently known about the impact of aging on unconventional mucosal T cell responses. We previously established that foodborne infection with a mouse-adapted internalin A mutant Listeria monocytogenes (Lm) generates an adaptive intestinal memory CD44^hi CD27^neg Vγ4 T cells capable of co-producing IL-17A and IFNγ. Therefore, we used this model to evaluate the impact of aging on adaptive Vγ4 T cell responses elicited by foodborne infection.

RESULTS

Foodborne Lm infection of female Balb/c and C57BL/6 mice led to an increased adaptive CD44^hi CD27^neg Vγ4 T cell response associated with aging. Moreover, Lm-elicited CD44^hi CD27^neg Vγ4 T cells maintained diverse functional subsets despite some alterations favoring IL-17A production as mice aged. In contrast to the documented susceptibility of aged mice to intravenous Lm infection, mice contained bacteria after foodborne Lm infection suggesting that elevated bacterial burden was not a major factor driving the increased adaptive CD44^hi CD27^neg Vγ4 T cell response associated with mouse age. However, CD44^hi CD27^neg Vγ4 T cells accumulated in naïve mice as they aged suggesting that an increased precursor frequency contributes to the robust Lm-elicited mucosal response observed. Body mass did not appear to have a strong positive association with CD44^hi CD27^neg Vγ4 T cells within age groups. Although an increased adaptive CD44^hi CD27^neg Vγ4 T cell response may contribute to foodborne Lm resistance of C57BL/6 mice aged 19 or more months, neither anti-TCRδ or anti-IL-17A treatment impacted Lm colonization after primary infection. These results suggest that γδTCR signaling and IL-17A are dispensable for protection after primary foodborne Lm infection consistent with the role of conventional T cells during the early innate immune response to Lm.

CONCLUSIONS

Lm-elicited adaptive Vγ4 T cells appear resistant to immunosenescence and memory Vγ4 T cells could be utilized to provide protective immune functions during enteric infection of aged hosts. As such, oral immunization might offer an efficient therapeutic approach to generate unconventional memory T cells in the elderly.

A blend of broadly-reactive and pathogen-selected Vγ4 Vδ1 T cell receptors confer broad bacterial reactivity of resident memory γδ T cells

Although murine γδ T cells are largely considered innate immune cells, they have recently been reported to form long-lived memory populations. Much remains unknown about the biology and specificity of memory γδ T cells. Here, we interrogated intestinal memory Vγ4 Vδ1 T cells generated after foodborne Listeria monocytogenes (Lm) infection to uncover an unanticipated complexity in the specificity of these cells. Deep TCR sequencing revealed that a subset of non-canonical Vδ1 clones are selected by Lm infection, consistent with antigen-specific clonal expansion. Ex vivo stimulations and in vivo heterologous challenge infections with diverse pathogenic bacteria revealed that Lm-elicited memory Vγ4 Vδ1 T cells are broadly reactive. The Vγ4 Vδ1 T cell recall response to Lm, Salmonella enterica serovar Typhimurium (STm) and Citrobacter rodentium was largely mediated by the γδTCR as internalizing the γδTCR prevented T cell expansion. Both broadly-reactive canonical and pathogen-selected non-canonical Vδ1 clones contributed to memory responses to Lm and STm. Interestingly, some non-canonical γδ T cell clones selected by Lm infection also responded after STm infection, suggesting some level of cross-reactivity. These findings underscore the promiscuous nature of memory γδ T cells and suggest that pathogen-elicited memory γδ T cells are potential targets for broad-spectrum anti-infective vaccines.

γδ T cell IFNγ production is directly subverted by Yersinia pseudotuberculosis outer protein YopJ in mice and humans

Yersinia pseudotuberculosis is a foodborne pathogen that subverts immune function by translocation of Yersinia outer protein (Yop) effectors into host cells. As adaptive γδ T cells protect the intestinal mucosa from pathogen invasion, we assessed whether Y. pseudotuberculosis subverts these cells in mice and humans. Tracking Yop translocation revealed that the preferential delivery of Yop effectors directly into murine Vγ4 and human Vδ2⁺ T cells inhibited anti-microbial IFNγ production. Subversion was mediated by the adhesin YadA, injectisome component YopB, and translocated YopJ effector. A broad anti-pathogen gene signature and STAT4 phosphorylation levels were inhibited by translocated YopJ. Thus, Y. pseudotuberculosis attachment and translocation of YopJ directly into adaptive γδ T cells is a major mechanism of immune subversion in mice and humans. This study uncovered a conserved Y. pseudotuberculosis pathway that subverts adaptive γδ T cell function to promote pathogenicity.

Unconventional γδ T cells are a dynamic immune population important for mucosal protection of the intestine against invading pathogens. We determined that the foodborne pathogen Y. pseudotuberculosis preferentially targets an adaptive subset of these cells to subvert immune function. We found that direct injection of Yersinia outer proteins (Yop) into adaptive γδ T cells inhibited their anti-pathogen functions. We screened all Yop effectors and identified YopJ as the sole effector to inhibit adaptive γδ T cell production of IFNγ. We determined that adaptive γδ T cell subversion occurred by limiting activation of the transcription factor STAT4. When we infected mice with Y. pseudotuberculosis expressing an inactive YopJ, this enhanced the adaptive γδ T cell response and led to greater cytokine production from this subset of cells to aid mouse recovery. This mechanism of immune evasion appears conserved in humans as direct injection of Y. pseudotuberculosis YopJ into human γδ T cells inhibited cytokine production. This suggested to us that Y. pseudotuberculosis actively inhibits the adaptive γδ T cell response through YopJ as a mechanism to evade immune surveillance at the site of pathogen invasion.

P13.14 Inhibition of extracellular carbonic anhydrases reduces glioblastoma cell invasion

BACKGROUND

Malignant gliomas metabolize glucose preferably by glycolysis which is in accordance with the Warburg effect. This induces a high demand of glucose combined with a significant lactic acid load. The hypoxia-inducible carbonic anhydrase (CA) IX has been shown to moderate the extrusion of hydrogen ions into the extracellular space. Since the acidification of the extracellular environment contributes to host tissue invasion due to activation of proteolytic enzymes, we hypothesized that CA IX plays an important role in malignant glioma Recently, specific small molecule inhibitors of this enzyme have been developed and may provide an innovative strategy for anti - invasive treatment.

MATERIAL AND METHODS

Two established and 4 primary GBM cell lines (2 with mesenchymal and 2 with proneural transcriptional profile) were exposed to the CAIX inhibitor U104 under normoxic and hypoxic conditions. Cell toxicity was measured by ATP and crystal violet assay. For invasion assessment, a matrigel invasion chamber system with 8 µm pore size polycarbonate filter was used. CAIX expression was analyzed by quantitative RTPCR and Western Blot.

RESULTS

Hypoxia significantly induced CAIX expression in all cell lines. Invasiveness increased significantly under hypoxic conditions in the mesenchymal cells (p &lt; 0.01). Regardless of oxygenation status, the mesenchymal group displayed significantly higher invasiveness compared to the proneural group (p = 0.006). Looking at all cell lines, invasion is significantly inhibited by U104, both under normoxic and hypoxic conditions (p &lt; 0.01). However, while the mesenchymal group showed the highest susceptibility to CAIX inhibition followed by the proneurally differentiated group, the established cell lines were entirely refractory to CAIX inhibition.

CONCLUSION

Our data demonstrate that CAIX inhibition can effectively inhibit invasion in malignant glioma cells independent from oxygenation status, however the effects are significantly influenced by cell type specific biological features.

Flupentixol/melitracen for chronic refractory cough after treatment failure with other neuromodulators

BACKGROUND: Gabapentin and baclofen are recommended for the treatment of chronic refractory cough (CRC). We investigated the efficacy of flupentixol/melitracen in patients unresponsive to these neuromodulators.METHODS: A total of 101 patients with CRC who failed to respond to gabapentin and baclofen were recruited, and treated with flupentixol/melitracen. The prevalence of cough resolution and changes in the Cough Symptom Score (CSS), cough thresholds to capsaicin, Hull Airway Reflux Questionnaire (HARQ), Leicester Cough Questionnaire (LCQ), Generalized Anxiety Disorder-7, Hamilton Anxiety Rating Scale, Patient Health Questionnaire-9, and Hamilton Depression Rating Scale-24 were evaluated after treatment.RESULTS: Ninety-eight patients (97.0%) completed the study. The overall successful cough resolution rate was 62.4% (63/101). Cough resolution was accompanied by an obvious decrease in the CSS and HARQ score and a remarkable increase in cough thresholds to capsaicin challenge and LCQ score, whereas anxiety and depression scores did not change significantly. The prevalence of adverse effects (e.g., insomnia and dizziness) was 21.8%. The prevalence of cough recurrence within 2 weeks after treatment cessation was 17.8%.CONCLUSION: Flupentixol/melitracen may be an efficacious option for CRC unresponsive to other neuromodulators.

P–313 Endometrial receptivity analysis for personalized embryo transfer in patients with recurrent implantation failure: a retrospective analysis of a Chinese cohort

Study question

To quantify the effectiveness of endometrial receptivity analysis (ERA)-guided personalized embryo transfer (pET) in Chinese women.

Summary answer

ERA-guided pET may remarkably improve pregnancy and implantation rates among Chinese women with Recurrent implantation failure (RIF).

What is known already

RIF is a major cause of infertility, and endometrial receptivity is widely accepted to impact implantation failure. Precision prediction of the WOI, the time when the endometrium is most receptive to the implantation of the embryo, is, therefore, of great significance to improve implantation prospects. Previous studies have shown the effectiveness of ERA for the prediction of the WOI, and how pET, timed by ERA, improves implantation and pregnancy rates; however, the efficacy of ERA-guided pET remains unknown for Chinese women.

Study design, size, duration

Patients in Chengdu Xi’nan Gynecology Hospital (Chengdu, China) who were undergoing frozen embryo transfer (FET) at the blastocyst stage on day five or day six during the period from November 2019 through September 2020 were recruited for this study. A total of 145 eligible patients were included in the study and assigned to the ERA group (n = 67) or the control group (n = 78). Clinical pregnancy outcomes were compared between the two groups.

Participants/materials, setting, methods

Endometrial specimens were collected the from ERA group. Total RNA was extracted from endometrial specimens, the transcriptomic sequencing data were processed using RNA-Seq and the endometrial receptivity status was assessed by the ERA predictor. The endometrium was classified as receptive or non-receptive according to the ERA assessment, and pET was done at the time determined by ERA in the ERA group. Subjects in the control group did not receive ERA and underwent blastocyst transfer normally.

Main results and the role of chance

The demographic and clinical characteristics were comparable between the ERA and control groups (P &gt; 0.05). The ERA test identified 10.45% of samples as receptive and 89.55% of samples as non-receptive in the ERA group, with 70.15% of samples presenting a pre-receptive profile. We observed higher cumulative pregnancy (74.63% vs. 64.10%) and cumulative implantation rate (47.32% vs. 21.68%) rates, and a lower biochemical pregnancy rate (18.00% vs. 34.00%) in the ERA group when compared to the control group (P &lt; 0.05). Additionally, we found higher pregnancy (67.16% vs. 39.74%) and implantation (46.54% vs. 16.94%) rates as well as a lower biochemical pregnancy rate (17.78% vs. 45.16%) after the first ERA test in the ERA group when compared to the control group (P &lt; 0.01).

Limitations, reasons for caution

First, this is a retrospective analysis, which is relatively more biased than prospective clinical trials. Second, the study sample is considerably small. Third, only 10.45% of the subjects were identified as presenting a receptive profile, which limits the comparisons of clinical outcomes between patients with receptive and non-receptive endometria.

Wider implications of the findings: This study demonstrates that the ERA test helps to determine the optimal timing for embryo transfer, improve pregnancy and implantation rates in patients with RIF, and guides the clinical application of the ERA test.

Trial registration number

approval No. 2020–018

P–371 Clinical value assessment between endometrial receptivity array and immune profiling in patients with implantation failure

Study question

To evaluate whether the pregnancy outcomes could be improved in implantation failure patients by endometrial receptivity array, endometrial immune profiling, or a combination of both.

Summary answer

There was no statistical difference between different endometrial receptivity evaluation and treatment in improving the clinical pregnancy rate.

What is known already

Both endometrial receptivity array and endometrial immune profiling were promised to improve the endometrial receptivity and subsequent clinical pregnancy. However, less is known about the efficiency between each other and whether the combination could further enhance their clinical value.

Study design, size, duration

Between November 2019 and September 2020, 143 women with a history of at least two or more consecutive implantation failure in IVF/ICSI treatment in Chengdu Xinan Gynecology Hospital were included. They were divided into three groups: ‘ERA + Immune Profiling’ (n = 70), ‘Immune Profiling’ (n = 41), and ‘ERA’ (n = 32).

Participants/materials, setting, methods

Inclusion criteria were age ≤ 38, with normal uterus and uterine cavity. All patients were suggested to evaluate endometrial receptivity by ERA test (Igenomix, Valencia, Spain) and endometrial immune profiling based on immunohistochemistry simultaneously, who would be free to choose each or both evaluation approaches. Personal Embryo Transfer and/or personal medical care were adopted according to evaluation results. Clinical pregnancy was confirmed by gestational sacs observed under ultrasonography.

Main results and the role of chance

The overall prevalence of displaced window of implantation (WOI) is 84.3%, and nearly 74.8% (83/111) patients were diagnosed as endometrial immune dysregulation. Clinical Pregnancy rate and embryonic implantation rate decreased in the ‘Immune Test’ groups, but without a statistical difference (P = 0.311, and 0.158, respectively). Multivariable logistic regression analysis showed that different endometrial receptivity evaluation and treatment was not associated the clinical pregnancy rate, suggesting the performance of different endometrial receptivity evaluation and treatment is similar in improving the clinical pregnancy rate. Neither the immune profiling (CD56, P = 0.591; FOXP3, P = 0.195; CD68, P = 0.820; CD163, P = 0.926; CD1a, P = 0.561; CD57, P = 0.221; CD8, P = 0.427; CD138 CE, P = 0.372) nor histologic endometrial dating defined by Noyes criteria (P = 0.374) were associated with ERA phases.

Limitations, reasons for caution

Although the selection of evaluation approaches was based on patients’ willingness, the variances of baseline characteristics and immune profiling existed in different groups. The immunological treatment efficacy based on immune profiling was not evaluated before embryo transfer.

Wider implications of the findings: To our knowledge, this is the first study comparing the pregnancy outcomes after two typical endometrial receptivity evaluation approaches. The findings highlight the unsubstitutability for each assessment, indicating that both asynchronous and pathological WOI contribute to implantation failure.

Trial registration number

X2019004

A blend of broadly-reactive and pathogen-selected Vγ4Vγδ1 T cell receptors confer broad bacterial reactivity of resident memory γδ T cells

γδ T cells are pleiotropic sentinels involved in immune defense at barrier tissues. While most γδ T cell subsets are associated with innate-like responses, foodborne Listeria monocytogenes (Lm) infection elicits a substantial resident memory Vγ4Vδ1 T cell response that appears specific to the priming pathogen despite limited T cell receptor (TCR) diversity. As our understanding of memory γδ T cells remains elusive, memory γδ T cells were examined using heterologous challenge infections coupled with TCRδ sequencing to reveal an unanticipated complexity in this memory compartment. CDR3δ sequence analysis revealed that a subset of non-canonical Vδ1 clones expanded during primary and secondary Lm infection but contracted at memory, consistent with antigen-specific clonal expansion. Additionally, canonical clones comprised most of the response, suggesting that some cells may not be Lm-restricted. Indeed, ex vivo stimulation of Lm-elicited memory γδ T cells with Salmonella enterica serovar typhimurium (STm), Yersinia pseudotuberculosis, and Citrobacter rodentium (Cr) induced a robust multifunctional response. Furthermore, heterologous STm-induced colitis infection and intraperitoneal Cr infection of Lm-immune mice led to the TCR-dependent recall of memory γδ T cells, demonstrating their broad reactivity in vivo. Interestingly, most of the non-canonical Vγ4Vδ1 T cell clones that expanded in an antigen-specific manner after Lm infection did not respond after STm infection, suggesting some level of specificity. These findings underscore the complex and promiscuous nature of memory γδ T cells and suggest that pathogen-elicited memory γδ T cells are potential targets for broad-spectrum anti-infective vaccines.

Adaptive γδ T cell function is directly subverted by the Yersinia pseudotuberculosis outer protein YopJ

Vγ4 T cells are an unconventional subset of T cells that protect the intestinal mucosa from pathogen invasion and capable of anamnestic responses. Yersinia pseudotuberculosis (Yptb) is a foodborne pathogen that invades through the intestinal mucosa and subverts immune function by translocation of Yersiniaouter protein (Yop) effectors into target cells. In this study, we evaluated the response of adaptive Vγ4 T cells to Yptb to determine if adaptive γδ T cells are a target of immune subversion. Tracking Yptb translocation of Yop effectors through a FRET-based reporter assay revealed targeted and preferential delivery of Yop effectors directly into adaptive γδ T cells inhibited anti-microbial IFNγ production. Using a series of recombinant Yptb deficient or defective in numerous pathogenicity genes revealed that direct subversion of the adaptive γδ T cell IFNγ response was mediated by the adhesion molecule YadA, the injectosome component YopB, and the YopJ effector. Thus, Yptb attachment and translocation of YopJ directly into adaptive γδ T cells is a major mechanism of γδ T cell subversion. RNA-Seq of adaptive γδ T cells revealed that a broad anti-pathogen gene signature was inhibited by translocation of YopJ and suggested a role of the STAT4 pathway in this process. Indeed, IL-12p40 promoted the adaptive γδ T cell IFNγ response and YopJ limited STAT4 phosphorylation levels. Importantly, circulating human Vδ2+T cells were similarly targeted and inhibited by the YopJ effector, highlighting a novel and conserved Yptb pathway that subverts adaptive γδ T cell function.

Mesenteric lymph node priming licenses intestinal CD103+ CD8 tissue-resident memory T cell development

CD8 tissue-resident memory T (TRM) cells provide front-line protective immunity at barrier tissues; however, mechanisms regulating their development are not completely understood. Priming dictates the migration of effector CD8 T cells to the tissue, while factors in the tissue induce in situ TRM cell differentiation. Whether priming also regulates in situ differentiation of CD8 TRM cells has not been addressed. Here, we demonstrate that T cell priming in the mesenteric lymph nodes (MLN) was the principal determinant of CD103+ CD8 TRM cell differentiation in the intestine. In contrast, CD8 T cells primed in the spleen were inefficient at differentiating into intestinal CD103+ TRM cells. Moreover, both CD103− and CD103+ naïve T cells were highly efficient in differentiating into CD103+ TRM cells in the intestine after priming in the MLN, suggesting preconditioning of naïve T cells by TGF-b during homeostasis had little impact on intestinal CD103+ TRM cell differentiation. We further demonstrate that MLN priming initiated CD103+ CD8 TRM cell signature gene expression and licensed rapid CD103+ CD8 TRM precursor cell differentiation in response to factors in the tissue by providing retinoic acid signaling to CD8 T cells. Thus, MLN priming is specialized to license intestinal CD103+ CD8 TRM cell development.

TGF-β: Many Paths to CD103+ CD8 T Cell Residency

CD8 tissue-resident memory T (T_RM) cells primarily reside in nonlymphoid tissues without recirculating and provide front-line protective immunity against infections and cancers. CD8 T_RM cells can be generally divided into CD69⁺ CD103⁻ T_RM cells (referred to as CD103⁻ T_RM cells) and CD69⁺ CD103⁺ T_RM cells (referred to as CD103⁺ T_RM cells). TGF-β plays a critical role in the development and maintenance of CD103⁺ CD8 T_RM cells. In this review, we summarize the current understanding of tissue-specific activation of TGF-β mediated by integrins and how it contributes to CD103⁺ CD8 T_RM cell development and maintenance. Furthermore, we discuss the underlying mechanisms utilized by TGF-β to regulate the development and maintenance of CD103⁺ CD8 T_RM cells. Overall, this review highlights the importance of TGF-β in regulating this unique subset of memory CD8 T cells that may shed light on improving vaccine design to target this population.

Prostaglandin E2 receptor subtypes 1 and 2 play a role in TGF-β1-induced renal fibrosis by regulating endoplasmic reticulum stress

OBJECTIVE

This study aimed to investigate the effects of prostaglandin E2 receptor subtypes 1 (EP1) and 2 (EP2) on endoplasmic reticulum (ER) stress induced by TGF-β1 in mouse mesangial cells (MCs) and to explore its potential mechanisms.

MATERIALS AND METHODS

Mouse mesangial cells were isolated and cultured. EP-siRNAs were transfected into mesangial cells for silencing EP1 and EP2. Mesangial cell proliferation was assessed by the CCK-8 method. Expression of PGE2 was measured by enzyme-linked immunosorbent assay (ELISA). GRP78, TRPC1, ERK1/2, and phospho-ERK1/2 levels were examined by Western blot.

RESULTS

TGF-β1 induced mesangial cell proliferation and increased PGE2 secretion. Besides, TGF-β1 significantly upregulated GRP78 and TRPC1 expression at the protein level. Phospho-ERK1/2 protein amounts were also increased (p<0.05). Compared with the TGF-β1 group, cell proliferation in the EP1-siRNA+TGF-β1 group was reduced, while GRP78, TRPC1, and ERK1/2 protein amounts were downregulated (p<0.05). EP1 agonist significantly enhanced above changes and their activities (p<0.05). EP1 antagonist significantly attenuated the above changes (p<0.05). Compared with TGF-β1 group, cell proliferation in EP2-siRNA+TGF-β1 group was increased, while GRP78, TRPC1, and ERK1/2 protein amounts were increased (p<0.05). EP2 agonist significantly attenuated the above changes (p<0.05).

CONCLUSIONS

EP1 receptor may increase TGF-β1-induced cell damage by increasing the activities of GRP78, TRPC1, and ERK1/2 via ER stress. Meanwhile, the EP2 receptor may reduce TGF-β1-induced cell damage by suppressing GRP78, TRPC1, and ERK1/2 activities, also via ER stress. EP1 inhibition and EP2 stimulation may be a therapeutic option for delaying renal fibrosis.

FTY720 reactivates cryptococcal granulomas in mice through S1P receptor 3 on macrophages

FTY720 is a treatment for relapsing remitting multiple sclerosis (MS). It is an analog of sphingosine-1-phosphate (S1P) and targets S1P receptors 1, 3, 4, and 5. Recent reports indicate an association between long-term exposure to FTY720 and cases of cryptococcal infection. Here, we studied the effect of FTY720 and its derivative, BAF312, which only target S1P receptors 1 and 5, in a mouse model of cryptococcal infection. We found that treatment with FTY720, but not with BAF312, led to decreased survival and increased organ burden in mouse cryptococcal granulomas. Both FTY720 and BAF312 caused a profound CD4+ and CD8+ T cell depletion in blood and lungs but only treatment with FTY720 led to cryptococcal reactivation. Treatment with FTY720, but not with BAF312, was associated with disorganization of macrophages and with M2 polarization at the granuloma site. In a cell system, FTY720 decreased phagocytosis and production of reactive oxygen species by macrophages, a phenotype recapitulated in the S1pr3-/- knockout macrophages. Our results suggest that FTY720 reactivates cryptococcosis from the granuloma through a S1P receptor 3-mediated mechanism and support the rationale for development of more-specific receptor modulators for therapeutic use of MS.

Influences of urinary kallidinogenase on neuronal apoptosis in cerebral infarction rats through Nrf2/ARE oxidative stress pathway

OBJECTIVE

To investigate the influences of urinary kallidinogenase on neuronal apoptosis in rats with cerebral infarction through the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) oxidative stress pathway.

MATERIALS AND METHODS

A total of 30 male rats were divided into group A (model control group), group B (rat model of cerebral infarction) and group C (rat model of cerebral infarction + medical treatment with urinary kallidinogenase). The percentage of cerebral infarct volume and the apoptosis of brain cells in the three groups of rats were detected via 2,3,5-Triphenyltetrazolium chloride (TTC) staining, the pathological morphology of brain tissues in the three groups of rats was observed via hematoxylin and eosin (HE) staining, and the protein levels of Nrf2 and superoxide dismutase 1 (SOD1) in the brain tissues in the three groups of rats were measured using the Western blotting assay.

RESULTS

The degree of neurological deficit in group B was remarkably higher than that in group A (p<0.05), and it was markedly decreased in group C compared to that in group B, displaying statistically significant differences (p<0.05). Compared to that in group A, the cell apoptosis was significantly aggravated in group B, while a remarkably alleviated cell apoptosis was observed in group C compared to that of group B, and the differences were statistically significant (p<0.05). The cerebral infarct volume accounted for 34.87% of the whole brain volume in group B, and a mild cerebral infarction was detected in group C, with a percentage of cerebral infarct volume of 21.14%. Group B showed a more evident increase in the cerebral infarct volume than in group C (p<0.05). Compared to those of group A, pyknotic nuclei and neuron staining of brain tissue cells were evidently increased, and the neuronal cell injury was aggravated in group B. Moreover, prominently decreased pyknotic nuclei and neuron staining (p<0.05) as well as mild neuronal cell injury (p<0.05) were detected in group C compared to those in group B. The levels of Nrf2 and SOD1 protein in the brain tissues in group B were remarkably lower than those of group C (p<0.05).

CONCLUSIONS

Urinary kallidinogenase can inhibit the neuronal apoptosis in rats and protect the rats from cerebral infarction, whose mechanism is associated with the activation of the Nrf2/ARE oxidative stress pathway.

Mucosal CD8 T Cell Responses Are Shaped by Batf3-DC After Foodborne Listeria monocytogenes Infection

While immune responses have been rigorously examined after intravenous Listeria monocytogenes (Lm) infection, less is understood about its dissemination from the intestines or the induction of adaptive immunity after more physiologic models of foodborne infection. Consequently, this study focused on early events in the intestinal mucosa and draining mesenteric lymph nodes (MLN) using foodborne infection of mice with Lm modified to invade murine intestinal epithelium (InlA^MLm). InlA^MLm trafficked intracellularly from the intestines to the MLN and were associated with Batf3-independent dendritic cells (DC) in the lymphatics. Consistent with this, InlA^MLm initially disseminated from the gut to the MLN normally in Batf3^–/– mice. Activated migratory DC accumulated in the MLN by 3 days post-infection and surrounded foci of InlA^MLm. At this time Batf3^–/– mice displayed reduced InlA^MLm burdens, implicating cDC1 in maximal bacterial accumulation in the MLN. Batf3^–/– mice also exhibited profound defects in the induction and gut-homing of InlA^MLm-specific effector CD8 T cells. Restoration of pathogen burden did not rescue antigen-specific CD8 T cell responses in Batf3^–/– mice, indicating a critical role for Batf3 in generating anti-InlA^MLm immunity following foodborne infection. Collectively, these data suggest that DC play diverse, dynamic roles in the early events following foodborne InlA^MLm infection and in driving the establishment of intestinal Lm-specific effector T cells.

Cutting Edge: Batf3 Expression by CD8 T Cells Critically Regulates the Development of Memory Populations

The basic leucine zipper transcription factor ATF-like 3 (BATF3) is required for the development of conventional type 1 dendritic cells that are essential for cross-presentation and CD8 T cell-mediated immunity against intracellular pathogens and tumors. However, whether BATF3 intrinsically regulates CD8 T cell responses is not well studied. In this article, we report a role for cell-intrinsic Batf3 expression in regulating the establishment of circulating and resident memory T cells after foodborne Listeria monocytogenes infection of mice. Consistent with other studies, Batf3 expression by CD8 T cells was dispensable for the primary response. However, Batf3 ^-/- T cells underwent increased apoptosis during contraction to contribute to a substantially reduced memory population. Batf3 ^-/- memory cells had an impaired ability to mount a robust recall response but remained functional. These findings reveal a cell-intrinsic role of Batf3 in regulating CD8 T cell memory development.

LncRNA DSCAM-AS1 promotes non-small cell lung cancer progression via regulating miR-577/HMGB1 axis

Non-small cell lung cancer (NSCLC) is a major source of cancer mortality. Long non-coding RNA DSCAM-AS1 has been certified to be involved in the pathogenesis of NSCLC. This study aimed to further investigate the potential mechanism of DSCAM-AS1 in NSCLC progression. The expressions of DSCAM-AS1, miR-577, and high mobility group box 1 (HMGB1) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay. Cell viability was assessed by Cell Counting Kit-8 (CCK-8) assay. Flow cytometry assay was conducted to monitor cell apoptosis. Cell migration and invasion were measured by transwell assay. Wnt/β-catenin pathway-related factors were detected by western blot assay. The relationship between DSCAM-AS1, miR-577, and HMGB1 was validated by bioinformatics analysis and dual-luciferase reporter assay. The xenograft mouse model was established to analyze tumor growth in vivo. DSCAM-AS1 and HMGB1 were upregulated, while miR-577 was downregulated in NSCLC tissues and cells. DSCAM-AS1 promoted cell proliferation, migration and invasion, and restrained cell apoptosis in NSCLC cells. Overexpression of HMGB1 reversed the effects of DSCAM-AS1 depletion on the progression of NSCLC. DSCAM-AS1 modulated HMGB1 expression by sponging miR-577. DSCAM-AS1 regulated the Wnt/β-catenin pathway by regulating miR-577 and HMGB1. DSCAM-AS1 knockdown blocked the tumor growth in vivo. In conclusion, DSCAM-AS1 facilitated NSCLC progression by regulating the HMGB1-mediated Wnt/β-catenin pathway, providing a promising therapeutic target for NSCLC.

Lymph Node Priming Licenses Intestinal CD103+ CD8 Tissue-Resident Memory T Cell Development

CD8 tissue-resident memory T (TRM) cells provide front-line protective immunity at barrier tissues. Understanding TRM cell development will provide significant insights for vaccine design targeting infections and cancers at barrier tissues. Here, we demonstrate that pathogen-induced inflammation and pathogen-derived cognate antigen had minimal impact on intestinal CD103+ TRM cell differentiation. Instead, T cell priming in the mesenteric lymph nodes (MLN) was the principal determinant of CD103+ TRM cell differentiation in the intestine. In contrast, T cells primed in the spleen were incapable of differentiating into intestinal CD103+ TRM cells. Foodborne rechallenge of spleen-primed memory T cells was unable to induce intestinal CD103+ TRM cell differentiation, suggesting initial priming promoted a lasting fate. Moreover, both CD103− and CD103+ naïve T cells were highly efficient in differentiating into CD103+ TRM cells in the intestine after priming in the MLN, suggesting preconditioning of naïve T cells by TGF-b during homeostasis had little impact on intestinal CD103+ TRM cell differentiation. We further demonstrate that MLN priming initiated a CD103+ TRM cell program before effector T cell migration to the intestine and promoted CD103+ TRM cell differentiation in situ in part by promoting CCR9 expression and the ability to respond to TGF-b in a cell-extrinsic manner. Thus, mesenteric lymph node priming is specialized to license intestinal CD103+ CD8 TRM cell development.

Diverse dendritic cell subsets promote infection and induction of CD8 T cell responses after foodborne Listeria monocytogenes infection

Listeria monocytogenes (Lm) is a common foodborne pathogen which causes mild gastrointestinal distress in healthy hosts, and systemic listeriosis in immunocompromised individuals. While immune responses have been rigorously examined after intravenous Lm infection, less is understood about Lm dissemination from the intestines or the induction of adaptive immune responses after physiologic infection through the consumption of contaminated food. Consequently, this study focused on the cells involved in early immune responses in the intestinal mucosa using foodborne Lm infection in mice. After foodborne infection, Lm trafficked intracellularly from the intestines to the mesenteric lymph nodes (MLN) and were associated with Batf3-independent dendritic cells (DC) in the lymphatics. Consistent with this observation, dissemination of Lm from the gut to the MLN occurred normally in Batf3−/− mice. Activated migratory DC accumulated in the MLN by 3 days post-infection (dpi) where they surrounded Lm foci. At this time, Lm burden in the MLN was reduced in Batf3−/− mice implicating Batf3-DC in the maximal accumulation of Lm. While both conventional type 1 DC (cDC1) and type 2 DC in the MLN contained Lm by 3 dpi, Batf3−/− mice exhibited a profound defect in the induction and gut homing of Lm-specific CD8 T cells. Surprisingly, restoration of pathogen burden was unable to restore CD8 T cell responses in Batf3−/− mice. Thus, cDC1 play a critical role in the generation of potent anti-Lm immunity following foodborne infection. Collectively, these data demonstrate that DC play diverse and dynamic roles in the early events that follow foodborne Lm infection, and in the establishment of protective, anti-Lm intestinal immunity.

Pathogen-elicited memory γδ T cells express a broadly reactive canonical TCR or a pathogen-specific non-canonical TCR

γδ T cells are critical sentinels protecting barrier surfaces against pathogens. However, our understanding of γδ T cell specificity remains limited. We previously identified a resident memory Vγ4Vδ1 T cell population elicited by foodborne Listeria monocytogenes (Lm) infection. Analysis of the CDR3δ sequences revealed that a large subset of non-canonical clones expanded during primary Lm infection, contracted during memory homeostasis and recalled after secondary Lm infection suggesting antigenic-specificity may be involved in this response. However, most of the response was elicited by cells bearing a canonical Vδ1 TCR suggesting that many Lm-elicited cells may not be Lm-specific. Indeed, stimulation of mesenteric lymph node cells from Lm-immune mice with diverse pathogens induced a functional response by Lm-elicited memory γδ T cells. Similarly, induction of Salmonella colitis (STm-colitis) in Lm-immune mice resulted in a TCR-dependent γδ T cell recall-like response, demonstrating that the majority of these memory cells respond to heterologous infection. Interestingly, most of the non-canonical γδ T cell clones that responded to Lm infection did not expand in response to STm-colitis suggesting some level of specificity is imparted by the priming pathogen. Importantly, other enteropathogens triggered a recall-like response of Lm-elicited memory γδ T cells. Adaptive γδ T cells were also generated after foodborne infection of germ-free mice and in response to diverse bacterial infections of SPF mice, indicating that this population can be induced by a broad range of disseminating pathogens and may provide a broad target for universal mucosal vaccines of the gut.

Distinct memory γδ T cell subsets are fine-tuned by TCR engagement and soluble signals to shape IFNγ and IL-17A responses

Unconventional T cells are essential for tissue homeostasis and protection against invading pathogens at barrier sites. γδ T cells are enriched at these interfaces where they can form memory populations that can be either beneficial or detrimental depending on the functional response elicited. However, our understanding of the factors regulating memory γδ T cell generation, activation and function remains limited. Foodborne Listeria monocytogenes (Lm) infection of Batf3−/− mice revealed a critical role for Batf3-dependent dendritic cells in the generation and function of adaptive γδ T cells. In line with this observation, IFNγ and IL-17A production and IFNγ/IL-17A co-production by memory γδ T cells were induced by heat-killed Lm after 24 hours in culture, and these responses were inhibited after MHC-II or CD11c depletion. The induction of cytokine production was tightly associated with Zap70/Syk phosphorylation, indicative of TCR activation. Although IL-12 is usually associated with type 1 responses, neutralization of IL-12/23p40 dramatically impaired IL-17A production whereas IFNγ response was only marginally affected. Surprisingly, classical TH17 polarizing cytokines had little impact on IL-17A production. Despite this conventional-like response, memory γδ T cells remained able to quickly produce IL-17A in response to supernatant or live Lm independently of TCR signaling. Thus, adaptive γδ T cells are a functionally diverse population that encompasses innate- and adaptive-like responses that are fine-tuned by the γδTCR and soluble signals. These insights may facilitate the development of new strategies eliciting specific functional subsets of memory γδ T cells tailored to various intestinal disease settings.

MiR-7 alleviates secondary inflammatory response of microglia caused by cerebral hemorrhage through inhibiting TLR4 expression

OBJECTIVE

This study was conducted to analyze the effect of miR-7 on the inflammatory response of microglia in vitro and in vivo by constructing an intracerebral hemorrhage model.

PATIENTS AND METHODS

In this study, we first established a model of cerebral hemorrhage in rat for in vivo experiments, and used lipoprotein (LPS) to induce an inflammatory response development in microglial cells, and constructed microglial inflammation models for in vitro experiments. Quantitative Real-time-polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-7 in the rat model of cerebral hemorrhage and microglia with inflammation. The effect of miR-7 on the inflammation caused by intracerebral hemorrhage was evaluated through measuring the expression of IL-1β, IL-8 and TNF-α by enzyme-linked immunosorbent assay (ELISA). Dual luciferase reporter assay was used to detect the binding site of miR-7 to TLR4. Western blot was used to evaluate the level of TLR4 after overexpression and knockdown of miR-7 and to evaluate whether miR-7 alleviated the secondary inflammatory response of microglia after cerebral hemorrhage by inhibiting the expression of TLR4.

RESULTS

The expression of miR-7 in the rat cerebral hemorrhage model and microglial inflammation model tissue was significantly lower than that in the normal control group. Expression of inflammatory cytokines including IL-1β, IL-8 and TNF-α was significantly increased in rats with intracerebral hemorrhage and microglial inflammation in rats, and the expression of these inflammatory cytokines was partially reversed after overexpression of miR-7. Double luciferase reporter gene and ELISA results showed that miR-7 could inhibit the expression of TLR4 and relieve the secondary inflammatory response of microglia after cerebral hemorrhage.

CONCLUSIONS

We demonstrated that, in in vivo and in vitro experiments, miR-7 could reduce the LPS-induced inflammatory response produced by microglial cells, and alleviate the inflammation in the brain of rats with cerebral hemorrhage.

Microbial diversity in the tick Argas japonicus (Acari: Argasidae) with a focus on Rickettsia pathogens

The soft tick Argas japonicus mainly infests birds and can cause human dermatitis; however, no pathogen has been identified from this tick species in China. In the present study, the microbiota in A. japonicus collected from an epidemic community was explored, and some putative Rickettsia pathogens were further characterized. The results obtained indicated that bacteria in A. japonicus were mainly ascribed to the phyla Proteobacteria, Firmicutes and Actinobacteria. At the genus level, the male A. japonicus harboured more diverse bacteria than the females and nymphs. The bacteria Alcaligenes, Pseudomonas, Rickettsia and Staphylococcus were common in nymphs and adults. The abundance of bacteria belonging to the Rickettsia genus in females and males was 7.27% and 10.42%, respectively. Furthermore, the 16S rRNA gene of Rickettsia was amplified and sequenced, and phylogenetic analysis revealed that 13 sequences were clustered with the spotted fever group rickettsiae (Rickettsia heilongjiangensis and Rickettsia japonica) and three were clustered with Rickettsia limoniae, which suggested that the characterized Rickettsia in A. japonicus were novel putative pathogens and also that the residents were at considerable risk for infection by tick-borne pathogens.

NP30 stimulates Th17 differentiation through DC in Schistosomiasis Japonicum

The murine monoclonal anti‐idiotypic antibody, NP30, is a potential vaccine candidate against Schistosoma japonicum. Previous studies have revealed that NP30 has an immunoregulatory effect, but the underlying mechanism for this effect remains unknown. This study shows that NP30 induces dendritic cell (DC) maturation and increases the production of pro‐inflammatory cytokines. The expression of CD86 and MHC II was upregulated in DCs following stimulation with NP30 in vitro. Moreover, NP30 induced Th17 polarization by increasing the production of IL‐6 and TGF‐β. In vivo, Th17 differentiation was induced by the production of key pro‐inflammatory cytokines, including IL‐6and TGF‐β, from DCs of NP30‐immunized mice. These results indicate that NP30 promotes Th17 polarization through DC activation, preventing serious schistosomiasis.

Managing Response Time Tails by Sharding

Matrix analytic methods are developed to compute the probability distribution of response times (i.e., data access times) in distributed storage systems protected by erasure coding, which is implemented by sharding a data object into N fragments, only K <; N of which are required to reconstruct the object. This leads to a partial-fork-join model with a choice of canceling policies for the redundant N − K tasks. The accuracy of the analytical model is supported by tests against simulation in a broad range of setups. At increasing workload intensities, numerical results show the extent to which increasing the redundancy level reduces the mean response time of storage reads and significantly flattens the tail of their distribution; this is demonstrated at medium-high quantiles, up to the 99th. The quantitative reduction in response time achieved by two policies for canceling redundant tasks is also shown: for cancel-at-finish and cancel-at-start, which limits the additional load introduced whilst losing the benefit of selectivity amongst fragment service times.

Nonlinear Decay and Plasma Heating by a Toroidal Alfvén Eigenmode

We demonstrate theoretically that a toroidal Alfvén eigenmode (TAE) can parametrically decay into a geodesic acoustic mode and kinetic TAE in a toroidal plasma. The corresponding threshold condition for the TAE amplitude is estimated to be |δB_{⊥}/B_{0}|∼O(10^{-4}). Here, δB_{⊥} and B_{0} are, respectively, the perturbed magnetic field of the pump TAE and the equilibrium magnetic field. This novel decay process, in addition to contributing to the nonlinear saturation of energetic-particle or α-particle driven TAE instability, could also contribute to the heating as well as regulating the transports of thermal plasmas.

Isolating Lymphocytes from the Mouse Small Intestinal Immune System

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to dietary antigens and commensal bacteria while mounting effective immune responses to enteropathogenic microbes. In addition, it has become clear that local intestinal immunity has a profound impact on distant and systemic immunity. Therefore, it is important to study how an intestinal immune response is induced and what the immunologic outcome of the response is. Here, a detailed protocol is described for the isolation of lymphocytes from small intestine inductive sites like the gut-associated lymphoid tissue Peyer's patches and the draining mesenteric lymph nodes and effector sites like the lamina propria and the intestinal epithelium. This technique ensures isolation of a large numbers of lymphocytes from small intestinal tissues with optimal purity and viability and minimal cross compartmental contamination within acceptable time constraints. The technical capability to isolate lymphocytes and other immune cells from intestinal tissues enables the understanding of immune responses to gastrointestinal infections, cancers, and inflammatory diseases.

Combining Adoptive Cell Therapy with Cytomegalovirus-Based Vaccine Is Protective against Solid Skin Tumors

Despite many years of research, cancer vaccines have largely been ineffective in the treatment of established cancers. Many barriers to immune-mediated destruction of malignant cells exist, and these likely limit the efficacy of cancer vaccines. In this study, we sought to enhance the efficacy of a cytomegalovirus (CMV)-based vaccine targeting melanoma by combining vaccination with other forms of immunotherapy. Adoptive cell therapy in humans and in animal models has been shown to be effective for tumor regression. Thus, in this study, we assessed whether CMV-based vaccines in combination with adoptively transferred antitumor T cells could provide greater antitumor protection than either therapy alone. Our results show that adoptive cell therapy greatly enhanced the antitumor effects of CMV-based vaccines targeting the foreign model antigen, OVA, or the melanoma differentiation antigen, gp100. Combination adoptive cell therapy and vaccination induced the upregulation of the inhibitory ligands, PD-L1, and Qa-1^b, on B16 tumor cells. This expression paralleled the infiltration of tumors by vaccine-stimulated T cells which also expressed high levels of the receptors PD-1 and NKG2A/C/E, suggesting a potential mechanism of tumor immune evasion. Surprisingly, therapeutic blockade of the PD-1/PD-L1 and NKG2A/Qa-1^b axes did not delay tumor growth following vaccination, suggesting that the presence of inhibitory ligands within malignant tissue may not be an effective biomarker for successful combination therapy with CMV-based vaccines. Overall, our studies show that therapeutic CMV-based vaccines in combination with adoptive T cell transfer alone are effective for tumor rejection.

Loss of acid ceramidase in myeloid cells suppresses intestinal neutrophil recruitment

Bioactive sphingolipids are modulators of immune processes and their metabolism is often dysregulated in ulcerative colitis, a major category of inflammatory bowel disease (IBD). While multiple axes of sphingolipid metabolism have been investigated to delineate mechanisms regulating ulcerative colitis, the role of acid ceramidase (AC) in intestinal inflammation is yet to be characterized. Here we demonstrate that AC expression is elevated selectively in the inflammatory infiltrate in human and murine colitis. To probe for mechanistic insight into how AC up-regulation can impact intestinal inflammation, we investigated the selective loss of AC expression in the myeloid population. Using a model of intestinal epithelial injury, we demonstrate that myeloid AC conditional knockout mice exhibit impairment of neutrophil recruitment to the colon mucosa as a result of defective cytokine and chemokine production. Furthermore, the loss of myeloid AC protects from tumor incidence in colitis-associated cancer (CAC) and inhibits the expansion of neutrophils and granulocytic myeloid-derived suppressor cells in the tumor microenvironment. Collectively, our results demonstrate a tissue-specific role for AC in regulating neutrophilic inflammation and cytokine production. We demonstrate novel mechanisms of how granulocytes are recruited to the colon that may have therapeutic potential in intestinal inflammation, IBD, and CAC.-Espaillat, M. P., Snider, A. J., Qiu, Z., Channer, B., Coant, N., Schuchman, E. H., Kew, R. R., Sheridan, B. S., Hannun, Y. A., Obeid, L. M. Loss of acid ceramidase in myeloid cells suppresses intestinal neutrophil recruitment.

A novel large fragment deletion in PLS3 causes rare X-linked early-onset osteoporosis and response to zoledronic acid

We identified a novel large fragment deletion from intron 9 to 3'UTR in PLS3 (E10-E16del) in one Chinese boy with X-linked early-onset osteoporosis and vertebral fractures, which expanded the pathogenic spectrum of X-linked early-onset osteoporosis. Treatment with zoledronic acid was beneficial for increasing BMD and reshaping the vertebral bodies of this patient.

INTRODUCTION

X-linked early-onset osteoporosis is a rare disease, which is characterized by low bone mineral density (BMD), vertebral compression fractures (VCFs), and/or long bone fractures. We aimed to detect the phenotype and the underlying pathogenic mutation of X-linked early-onset osteoporosis in a boy from a nonconsanguineous Chinese family.

METHODS

We investigated the pathogenic mutation of the patient with X-linked early-onset osteoporosis by targeted next-generation sequencing and confirmed it by Sanger sequencing. We also observed the effects of zoledronic acid on fracture frequency and BMD of the patient.

RESULTS

Low BMD and multiple VCFs were the main phenotypes of X-linked early-onset osteoporosis. We identified a total of 12,229 bp deletion in PLS3, involving intron 9 to the 3'UTR (E10-E16 del). This large fragment deletion might be mediated by Alu repeats and microhomology of 26 bp at each breakpoint junction. Zoledronic acid treatment could significantly increase the Z-score of BMD and reshape the compressed vertebral bodies.

CONCLUSION

We identified a large fragment deletion mutation in PLS3 for the first time and elucidated the possible mechanism of the deletion, which led to X-linked early-onset osteoporosis and multiple vertebral fractures. Our findings would enrich the etiology spectrum of this rare disease.