Plasma membrane repair empowers the necrotic survivors as innate immune modulators.

The plasma membrane is crucial to the survival of animal cells, and damage to it can be lethal, often resulting in necrosis. However, cells possess multiple mechanisms for repairing the membrane, which allows them to maintain their integrity to some extent, and sometimes even survive. Interestingly, cells that survive a near-necrosis experience can recognize sub-lethal membrane damage and use it as a signal to secrete chemokines and cytokines, which activate the immune response. This review will present evidence of necrotic cell survival in both in vitro and in vivo systems, including in C. elegans, mouse models, and humans. We will also summarize the various membrane repair mechanisms cells use to maintain membrane integrity. Finally, we will propose a mathematical model to illustrate how near-death experiences can transform dying cells into innate immune modulators for their microenvironment. By utilizing their membrane repair activity, the biological effects of cell death can extend beyond the mere elimination of the cells.

Pathological pathway analysis in an experimental rheumatoid arthritis model and the tissue repair effect of acupuncture at ST36.

Rheumatoid arthritis (RA) is an autoimmune disease that generally affects the joints. In the face of inflammation-induced cartilage and bone damage, RA treatment remains insufficient. While research evidence indicates that acupuncture can exert anti-inflammatory and analgesic effects, improve the joint function of RA patients, and delay the disease, data on whether it can promote RA repair are lacking. Findings from the present work demonstrated that both the antigen-induced arthritis (AIA) and collagen-induced arthritis (CIA) models can simulate joint swelling of RA. The AIA model was more stable than the CIA model, with a higher incidence of successful arthritis modeling. Moreover, the AIA mice model could simulate the signal molecules and related pathological processes of the autoimmune response in RA, as well as major pathways related to RA and antigen immune response mechanisms. Manual acupuncture (MA) at Zusanli (ST36) significantly improved paw redness and swelling, pain, and inflammatory cell infiltration in the joints in AIA mice. The therapeutic effect of MA on AIA is achieved primarily through the regulation of steroid hormone biosynthesis, cell metabolism, and tissue repair processes. MA at ST36 can increase the gene contents of tissue repair growth factors, including PEG3, GADD45A, GDF5, FGF5, SOX2, and ATP6V1C2 in the inflammatory side joints of AIA mice, as well as the gene expression of the anti-inflammatory cytokine IL-10. In conclusion, acupuncture may alleviate RA in the joints via modulating the tissue healing process.

[Current situation and prospect of researches on regularities and mechanisms of acupuncture-moxibustion in alleviating chronic inflammatory response].

The inflammatory response plays an important role in the onset, development and prognosis of inflammatory diseases and a variety of chronic diseases. Long-term uncontrolled inflammatory response may lead to dysfunction or loss of organ tissue function. Clinical practice and evidence-based medicine suggest that acupuncture can effectively alleviate the inflammatory status of various inflammatory diseases and chronic diseases. Stimulation of acupoints related to internal organs and target organs can initiate neuromodulation by modulating the microenvironment of acupoints. After integration of acupuncture stimulus information in the central nervous system, neurotransmitters, hormones, etc. are released and ultimately act on immune cells through neuro-endocrine-immune pathways, such as the vagus-mediated cholinergic anti-inflammatory pathway, vagus nerve-adrenal medullary-dopamine pathway, somatic sympathetic nerve pathway, and hypothalamic-pituitary-adrenal axis, etc. Ultimately, the intracellular signaling pathways and polarization balance of monocytes/macrophages and T cell subsets are regulated and the immune homeo-stasis of target organs of the body realizes. Therefore, we proposed that the anti-inflammatory action of acupuncture may be one of the universal therapeutic strategies for multiple diseases, and a powerful interpretation of acupuncture in regulating the balance of yin and yang. The elucidation of its anti-inflammatory action rules and mechanism may better realize the clinical transformation of acupuncture and moxibustion precision treatment.

The autonomic nervous system: A potential link to the efficacy of acupuncture.

The autonomic nervous system (ANS) is a diffuse network that regulates physiological systems to maintain body homeostasis by integrating inputs from the internal and external environment, including the sympathetic, parasympathetic, and enteric nervous systems (ENS). Recent evidence suggests that ANS is one of the key neural pathways for acupuncture signal transduction, which has attracted worldwide attention in the acupuncture field. Here, we reviewed the basic and clinical research published in PubMed over the past 20 years on the effects of acupuncture on ANS regulation and homeostasis maintenance. It was found that acupuncture effectively alleviates ANS dysfunction-associated symptoms in its indications, such as migraine, depression, insomnia, functional dyspepsia, functional constipation. Acupuncture stimulation on some specific acupoints activates sensory nerve fibers, the spinal cord, and the brain. Using information integration and efferents from a complex network of autonomic nuclei of the brain, such as the insular cortex (IC), prefrontal cortex, anterior cingulate cortex (ACC), amygdala (AMG), hypothalamus, periaqueductal gray (PAG), nucleus tractus solitarius (NTS), ventrolateral medulla (VLM), nucleus ambiguus (AMB), acupuncture alleviates visceral dysfunction, inflammation via efferent autonomic nerves, and relieves pain and pain affect. The modulating pattern of sympathetic and parasympathetic nerves is associated with acupuncture stimulation on specific acupoints, intervention parameters, and disease models, and the relationships among them require further exploration. In conclusion, ANS is one of the therapeutic targets for acupuncture and mediates acupuncture's actions, which restores homeostasis. A systemic study is needed to determine the rules and mechanisms underlying the effects of acupoint stimulation on corresponding organs mediated by specific central nervous networks and the efferent ANS.

Mobilizing phospholipids on tumor plasma membrane implicates phosphatidylserine externalization blockade for cancer immunotherapy.

In "healthy" tumor cells, phosphatidylserine (PS) is predominately localized in the inner plasma membrane leaflet. During apoptosis, PS relocates to the outer leaflet. Herein, we established PSout tumor models with tumor cells lacking PS flippase component CDC50A, constantly exposing PS but alive. PSout tumors developed bigger than wild-type (WT) tumors, featuring M2 polarized tumor-associated macrophages (TAMs) and fewer tumor-antigen-specific T cells. The PS receptor TIM-3 is responsible for PS recognition. Employing an opposite tumor model, PSin, with tumor cells lacking the PS scramblase Xkr8 and unable to expose PS during otherwise normal apoptosis, we find that the accumulated apoptotic tumor cells produce and release cyclic GAMP (cGAMP) to immune cells to activate the STING pathway, leading to TAM M1 polarization, suppressed interleukin (IL)-10 secretion, and natural killer (NK) cell cytotoxicity. Silencing Xkr8 in vivo by either short hairpin RNA (shRNA) or small interfering RNA (siRNA) to achieve a PS externalization blockade provides robust therapeutic anti-tumor efficiency.

LANCE: a Label-Free Live Apoptotic and Necrotic Cell Explorer Using Convolutional Neural Network Image Analysis.

Identifying and quantifying cell death is the basis for all cell death research. Current methods for obtaining these quantitative measurements rely on established biomarkers, yet the marker-based approach suffers from limited marker specificity, high cost of reagents, lengthy sample preparation, and fluorescence imaging. Based on the morphological difference, we developed a Live, Apoptotic, and Necrotic Cell Explorer (LANCE) to categorize cell death status in a label-free manner, by incorporating machine learning and image processing. The LANCE workflow includes cropping individual cells from microscopic images having hundreds of cells, formation of an image database of around 5000 events, training and validation of the convolutional neural network models using multiple cell lines, and treatment conditions. With LANCE, we precisely categorized live, apoptotic, and necrotic cells with a high accuracy of 96.3 ± 0.5%. More importantly, the nondestructive label-free LANCE method allows for tracking time dynamics of the cell death process, which enhances the understanding of subtle cell death regulation at the molecular level. Hence, LANCE is a fast, low-cost, and nondestructive label-free method to distinguish cell status, which can be applied to cell death studies as well as many other biomedical applications.

Thymidine rescues ATR kinase inhibitor-induced deoxyuridine contamination in genomic DNA, cell death, and interferon-α/ß expression.

ATR kinase is a central regulator of the DNA damage response (DDR) and cell cycle checkpoints. ATR kinase inhibitors (ATRi's) combine with radiation to generate CD8+ T cell-dependent responses in mouse models of cancer. We show that ATRi's induce cyclin-dependent kinase 1 (CDK1)-dependent origin firing across active replicons in CD8+ T cells activated ex vivo while simultaneously decreasing the activity of rate-limiting enzymes for nucleotide biosynthesis. These pleiotropic effects of ATRi induce deoxyuridine (dU) contamination in genomic DNA, R loops, RNA-DNA polymerase collisions, and interferon-α/ß (IFN-α/ß). Remarkably, thymidine rescues ATRi-induced dU contamination and partially rescues death and IFN-α/ß expression in proliferating CD8+ T cells. Thymidine also partially rescues ATRi-induced cancer cell death. We propose that ATRi-induced dU contamination contributes to dose-limiting leukocytopenia and inflammation in the clinic and CD8+ T cell-dependent anti-tumor responses in mouse models. We conclude that ATR is essential to limit dU contamination in genomic DNA and IFN-α/ß expression.

Isoforms of Neuropilin-2 Denote Unique Tumor-Associated Macrophages in Breast Cancer.

Tumor-associated macrophages (TAMs) exert profound influence over breast cancer progression, promoting immunosuppression, angiogenesis, and metastasis. Neuropilin-2 (NRP2), consisting of the NRP2a and NRP2b isoforms, is a co-receptor for heparin-binding growth factors including VEGF-C and Class 3 Semaphorins. Selective upregulation in response to environmental stimuli and independent signaling pathways endow the NRP2 isoforms with unique functionality, with NRP2b promoting increased Akt signaling via receptor tyrosine kinases including VEGFRs, MET, and PDGFR. Although NRP2 has been shown to regulate macrophage/TAM biology, the role of the individual NRP2a/NRP2b isoforms in TAMs has yet to be evaluated. Using transcriptional profiling and spectral flow cytometry, we show that NRP2 isoform expression was significantly higher in TAMs from murine mammary tumors. NRP2a/NRP2b levels in human breast cancer metastasis were dependent upon the anatomic location of the tumor and significantly correlated with TAM infiltration in both primary and metastatic breast cancers. We define distinct phenotypes of NRP2 isoform-expressing TAMs in mouse models of breast cancer and within malignant pleural effusions from breast cancer patients which were exclusive of neuropilin-1 expression. Genetic depletion of either NRP2 isoform in macrophages resulted in a dramatic reduction of LPS-induced IL-10 production, defects in phagosomal processing of apoptotic breast cancer cells, and increase in cancer cell migration following co-culture. By contrast, depletion of NRP2b, but not NRP2a, inhibited production of IL-6. These results suggest that NRP2 isoforms regulate both shared and unique functionality in macrophages and are associated with distinct TAM subsets in breast cancer.

Sensing plasma membrane pore formation induces chemokine production in survivors of regulated necrosis.

Although overwhelming plasma membrane integrity loss leads to cell lysis and necrosis, cells can tolerate a limited level of plasma membrane damage, undergo ESCRT-III-mediated repair, and survive. Here, we find that cells which undergo limited plasma membrane damage from the pore-forming actions of MLKL, GSDMD, perforin, or detergents experience local activation of PKCs through Ca2+ influx at the damage sites. S660-phosphorylated PKCs subsequently activate the TAK1/IKKs axis and RelA/Cux1 complex to trigger chemokine expressions. We observe that in late-stage cancers, cells with active MLKL show expression of CXCL8. Similar expression induction is also found in ischemia-injured kidneys. Chemokines generated in this manner are also indispensable for recruiting immune cells to the dead and dying cells. This plasma membrane integrity-sensing pathway is similar to the well-established yeast cell wall integrity signaling pathway at molecular level, and this suggests an evolutionary conserved mechanism to respond to the cellular barrier damage.

["Acupuncture network drug"--transformation and application strategies of exosomes based on characteristics of network regulation of acupuncture therapy].

Although the basic mechanism of acupuncture-moxibustion has been revealed from many aspects, there are still many shackles in the transformation of the related research achievements. The transformation of academic achievements of experimental acupunctology is an urgent issue to be solved at present. Network regulation is the basic action mode of acupuncture therapy. In the present paper, we proposed that the "acupuncture network drug" could carry a variety of effective active ingredients which may be the core component of network regulation of acupuncture therapy. The "exosomes", polyvesicle derived from the intracellular lysosomal microparticles invagination, contain complex RNAs and proteins and exist in the body fluids and function in secreting abundant activate substances to participate in intercellular communication, which is the research hotspot in the field of frontier life science in the world. They play an important role in the diagnosis and treatment of diseases, and drug development, etc.. Our studies using rats with adjuvant arthritis and mice with sepsis displayed that after intraperitoneal administration of serum exosomes derived from normal animals receiving acupuncture intervention, an acupuncture-like analgesic effect and an anti-inflammatory effect were achieved, respectively. It is thus possible that acupuncture network drugs could be developed from serum exosomes secreted by exosome autogenous living cells after acupuncture intervention by virtue of the characteristics of low immunogenicity and may have great advantages in drug development and modification. It is also expected to provide new ideas for the transformation of experimental research results and to in depth give explanations about the underlying mechanisms of acupuncture therapy.

Bloodletting Puncture at Hand Twelve Jing-Well Points Relieves Brain Edema after Severe Traumatic Brain Injury in Rats via Inhibiting MAPK Signaling Pathway.

OBJECTIVE: To investigate whether blood-brain barrier (BBB) served a key role in the edema-relief effect of bloodletting puncture at hand twelve Jing-well points (HTWP) in traumatic brain injury (TBI) and the potential molecular signaling pathways. METHODS: Adult male Sprague-Dawley rats were assigned to the sham-operated (sham), TBI, and bloodletting puncture (bloodletting) groups (n=24 per group) using a randomized number table. The TBI model rats were induced by cortical contusion and then bloodletting puncture were performed at HTWP twice a day for 2 days. The neurological function and cerebral edema were evaluated by modified neurological severity score (mNSS), cerebral water content, magnetic resonance imaging and hematoxylin and eosin staining. Cerebral blood flow was measured by laser speckles. The protein levels of aquaporin 4 (AQP4), matrix metalloproteinases 9 (MMP9) and mitogen-activated protein kinase pathway (MAPK) signaling were detected by immunofluorescence staining and Western blot. RESULTS: Compared with TBI group, bloodletting puncture improved neurological function at 24 and 48 h, alleviated cerebral edema at 48 h, and reduced the permeability of BBB induced by TBI (all P<0.05). The AQP4 and MMP9 which would disrupt the integrity of BBB were downregulated by bloodletting puncture (P<0.05 or P<0.01). In addition, the extracellular signal-regulated kinase (ERK) and p38 signaling pathways were inhibited by bloodletting puncture (P<0.05). CONCLUSIONS: Bloodletting puncture at HTWP might play a significant role in protecting BBB through regulating the expressions of MMP9 and AQP4 as well as corresponding regulatory upstream ERK and p38 signaling pathways. Therefore, bloodletting puncture at HTWP may be a promising therapeutic strategy for TBI-induced cerebral edema.

Exploration of Stratified Evidence Scoring Method of Acupuncture Clinical Practice Guidelines.

Due to its own internal laws of development, Chinese medicine (CM) seems more inclined to empirical medicine in a relatively long historical period. It is considered to be lacking objective and unified clinical practice guidelines (CPGs), and the difficulties in diagnosis and therapeutic effect evaluation comes with it, have restricted its further inheritance, development and international communication. Over the years, our research group has been committed to improving the standardization theory and methodology of CM, also perfecting relative techniques for further application, which are all based on the stratified evidence scoring method. We have already applied this method to 45 issued guidelines, including 5 national guidelines, 3 industrial guidelines, and 37 formulation/revision social organization guidelines. The stratified evidence scoring method has been recognized and used widely. It helps scholars and applicators to study, formulate, publish and popularize the acupuncture therapy clinical practice guidelines better, thus further promotes the development of acupuncture therapy.

Initiation of Acupoint Molecular Mechanisms for Manual Acupuncture Analgesia-Nuclear Factor κB Signaling Pathway.

OBJECTIVE: To identify the prominent molecular signaling in acupoints and explore their roles in initiating the analgesia effect of manual acupuncture (MA). METHOD: A three-step study was conducted, the experiment 1 was a genome-wide analysis of the tissue at acupoint Zusanli (ST 36), including 12 Wistar rats which were divided into control, control+MA1, and control+MA7 groups. In the experiment 2, the paw withdrawal latency (PWL), immunohistochemistry and Western blot analysis of phospho-nuclear factor kappa B (NFκB) p65 (p-p65), phospho-NFκB p50 (p-p50) at ST 36 were performed on rats of saline, saline+MA, and complete Freund's adjuvant (CFA)+MA groups (n=6). In experiment 3, 24 rats were divided into saline+DMSO, CFA+DMSO, CFA+DMSO+MA, and CFA+BAY 11-7082+MA groups, the PWL and immunofluorescence assay of NFκB p65 at ST 36 was conducted. RESULT: (1) The gene: inhibitor of NFκB (Nfkbia), interleukin-1ß (Il1b), interleukin-6 (Il6), chemokine c-x-c motif ligand 1 (Cxcl1), monocyte chemoattractant protein-1 (MCP-1/Ccl2) expressions in the control+MA7 group were significantly increased (P<0.05 or P<0.01), and the expression of NFκB p65 (Rela), NFκB p50 (Nfkb1) were increased in the control+MA7 group (P<0.05). (2) CFA+MA groups showed increased PWL from day 1 to 7 (P<0.01 vs. CFA), and the Western blot results were consistent with immunohistochemistry, the expression of NFκB p-p65 and NFκB p-p50 were significantly increased in the MA-related groups compared with control and CFA groups (P<0.05). (3) Compared with the CFA+DMSO+MA group, the PWL of the CFA+ BAY 11-7082+MA group decreased significantly and continued until day 5 and 7 (P<0.05 and P<0.01, respectively), and the NFκB p65 expression of CFA+BAY 11-7082+MA was significantly reduced compared with CFA+DMSO+MA (P<0.01). CONCLUSION: Local NFκB signaling cascade in acupoint caused by MA is an important step in initiating the analgesic effect, which would provide new evidence for the initiation of MA-effect and improve the understanding of the scientific basis of acupuncture analgesia.

The effectiveness of cupping therapy on chronic fatigue syndrome: A single-blind randomized controlled trial.

BACKGROUND: and purpose: We investigated the effectiveness of cupping therapy with three different pressures in patients with chronic fatigue syndrome (CFS). MATERIALS AND METHODS: The participants were randomly assigned to three groups, as follows: cupping pressure of -0.02 mpa (n = 38), -0.03 mpa (n = 38), or -0.05 mpa (n = 36). Each group received cupping treatment that consisted of 10 sessions over 5 weeks (2 sessions per week). The primary outcomes were Fatigue Scale (FS-14) score and Fatigue Assessment Instrument (FAI) score after 5 and 10 sessions. The secondary outcomes were the Self-Rating Anxiety Scale (SAS) score, the Self-Rating Depression Scale (SDS) score, and the Pittsburgh Sleep Quality Index (PSQI) score. RESULTS: There were 91 participants who completed the trial. After five sessions of treatment, the primary outcome of FS-14 score decreased by 3.20 (2.19, 4.21) in the -0.02 mpa group, by 2.39 (1.51, 3.27) in the -0.03 mpa group, and by 3.40 (2.28, 4.52) in the -0.05 mpa group (P = 0.667). After 10 sessions of treatment, the outcome of FS-14 score decreased by 5.00 (3.79, 6.21) in the -0.02 mpa group, by 4.06 (3.07, 5.05) in the -0.03 mpa group, and by 4.77 (3.52, 5.94) in the -0.05 mpa group (P = 0.929). And, the results were statistically different between 5 sessions and 10 sessions of treatment (P < 0.01). However, there were no statistical differences in FAI, SAS, SDS, and PSQI scores between the three groups after 5 sessions and 10 sessions of treatment. CONCLUSIONS: In conclusion, cupping therapy has significantly relieved fatigue symptoms and improved emotion and sleep condition of CFS patients, and 10 sessions of treatment had superior results compared with 5 sessions in each group. Moreover, in 5 sessions of treatment, cupping with high pressure showed better improvement in fatigue syndromes and sleep condition according to effective rates. TRIAL REGISTRATION: Chinese clinical trial registry (ChiCTR1800017590); Ethical approval number: ChiECRCT-20180085.

[Indication of bloodletting therapy based on multi-dimensional evidence assessment].

The indication of bloodletting therapy was determined based on the multi-dimensional evidence assessment, which could provide guidance for the clinical application of bloodletting therapy. The literature of bloodletting therapy was comprehensively collected by retrieval in CNKI, Wanfang and VIP databases (until February 23, 2019), modern books in Library of Tianjing University of TCM and the Chinese Medical Code (Fifth Edition). The disease spectrum of bloodletting therapy was determined by self-designed questionnaire survey e-mailed to relevant experts. The indication of bloodletting therapy was determined by Delphi expert meeting. As a result, 746 pieces of ancient literature and 32 775 modern literature were included. The indications of bloodletting therapy based on the multi-dimensional evidence assessment include herpes zoster, acne, acute tonsillitis, vascular headache, varicose veins of lower extremities, acute lumbar sprain, early erysipelas, wheat swelling, exogenous fever of children, stroke, which are mainly the syndromes of blood stasis, toxin, excess and heat.

To the edge of cell death and back.

Programmed cell death plays a central role in maintaining homeostasis. Various studies have demonstrated that programmed cell death is not a one-way street; cells can survive even when the core cell death processes are underway. Cell death initiation, prevention, and recovery function in a coordinated fashion to establish and maintain a homeostatic environment. In this review, we discuss how dying cells can be rescued from death's grip and the subsequent physiological consequences. We suggest a fundamental question to be answered-at least at the single cell level is, can we predict if a certain cell is more or less likely to survive or die? And importantly, what physiological and pathological consequences, as well as therapeutic approaches can we delineate from this ability to predict cell death versus survival.

Biological events and molecular signaling following MLKL activation during necroptosis.

Necroptosis is a form of programmed necrotic cell death mediated by the kinase RIPK3 and its substrate MLKL. MLKL, which displays plasma membrane (PM) pore-forming activity upon phosphorylation, functions as the executioner during necroptosis. Thus, it was previously assumed that MLKL phosphorylation is the endpoint of the necroptotic signaling pathway. Here, we summarize several events that characterize the dying necroptotic cells after MLKL phosphorylation, including Ca2+ influx, phosphatidylserine (PS) externalization, PM repair by ESCRT-III activation, and the final compromise of PM integrity. These processes add several unexpected regulatory events downstream of MLKL signaling. We have also observed that CoCl2, which may mimic hypoxia, can induce necroptosis, which suggests that in vivo triggers of necroptosis might include a transient lack of O2.

ESCRT-III Acts Downstream of MLKL to Regulate Necroptotic Cell Death and Its Consequences.

The activation of mixed lineage kinase-like (MLKL) by receptor-interacting protein kinase-3 (RIPK3) results in plasma membrane (PM) disruption and a form of regulated necrosis, called necroptosis. Here, we show that, during necroptosis, MLKL-dependent calcium (Ca2+) influx and phosphatidylserine (PS) exposure on the outer leaflet of the plasma membrane preceded loss of PM integrity. Activation of MLKL results in the generation of broken, PM "bubbles" with exposed PS that are released from the surface of the otherwise intact cell. The ESCRT-III machinery is required for formation of these bubbles and acts to sustain survival of the cell when MLKL activation is limited or reversed. Under conditions of necroptotic cell death, ESCRT-III controls the duration of plasma membrane integrity. As a consequence of the action of ESCRT-III, cells undergoing necroptosis can express chemokines and other regulatory molecules and promote antigenic cross-priming of CD8+ T cells.

Innate immune sensing of bacterial modifications of Rho GTPases by the Pyrin inflammasome.

Cytosolic inflammasome complexes mediated by a pattern recognition receptor (PRR) defend against pathogen infection by activating caspase 1. Pyrin, a candidate PRR, can bind to the inflammasome adaptor ASC to form a caspase 1-activating complex. Mutations in the Pyrin-encoding gene, MEFV, cause a human autoinflammatory disease known as familial Mediterranean fever. Despite important roles in immunity and disease, the physiological function of Pyrin remains unknown. Here we show that Pyrin mediates caspase 1 inflammasome activation in response to Rho-glucosylation activity of cytotoxin TcdB, a major virulence factor of Clostridium difficile, which causes most cases of nosocomial diarrhoea. The glucosyltransferase-inactive TcdB mutant loses the inflammasome-stimulating activity. Other Rho-inactivating toxins, including FIC-domain adenylyltransferases (Vibrio parahaemolyticus VopS and Histophilus somni IbpA) and Clostridium botulinum ADP-ribosylating C3 toxin, can also biochemically activate the Pyrin inflammasome in their enzymatic activity-dependent manner. These toxins all target the Rho subfamily and modify a switch-I residue. We further demonstrate that Burkholderia cenocepacia inactivates RHOA by deamidating Asn 41, also in the switch-I region, and thereby triggers Pyrin inflammasome activation, both of which require the bacterial type VI secretion system (T6SS). Loss of the Pyrin inflammasome causes elevated intra-macrophage growth of B. cenocepacia and diminished lung inflammation in mice. Thus, Pyrin functions to sense pathogen modification and inactivation of Rho GTPases, representing a new paradigm in mammalian innate immunity.