脓毒症中的细胞凋亡

脓毒症指机体对感染产生的全身性炎症反应的综合征,常发生于外伤、烧伤或免疫力低下时病原体严重感染,重者可发展为感染性休克、DIC和多器官功能衰竭等改变[1].脓毒症的发病机制与感染病原体、宿主免疫系统、炎症反应和凝血系统之间复杂的相互作用密切相关,其中全身炎症反应综合征(systemic inflammatory response syndrome,SIRS)、多器官损伤和感染性休克是常见的病理生理过程,但由于具体机制尚不明确,临床治疗效果不佳,死亡率一直居高不下[2,3].近年来研究显示细胞凋亡变化是脓毒症重要的病理变化之一[4].细胞凋亡(apoptosis)又称程序性细胞死亡,是机体形态发生、组织重塑和免疫反应消退过程中的一种主动性的死亡方式.与细胞坏死不同,凋亡的细胞或凋亡小体可被临近细胞所吞噬而不引起周围组织炎症反应.     

Gemcitabine sensitizes lung cancer cells to Fas/FasL system‐mediated killing

Gemcitabine is a chemotherapy agent commonly used in the treatment of non‐small cell lung cancer (NSCLC) that has been demonstrated to induce apoptosis in NSCLC cells by increasing functionally active Fas expression. The aim of this study was to evaluate the Fas/Fas ligand (FasL) system involvement in gemcitabine‐induced lung cancer cell killing. NSCLC H292 cells were cultured in the presence or absence of gemcitabine. FasL mRNA and protein were evaluated by real‐time PCR, and by Western blot and flow cytometry, respectively. Apoptosis of FasL‐expressing cells was evaluated by flow cytometry, and caspase‐8 and caspase‐3 activation by Western blot and a colorimetric assay. Cytotoxicity of lymphokine‐activated killer (LAK) cells and malignant pleural fluid lymphocytes against H292 cells was analysed in the presence or absence of the neutralizing anti‐Fas ZB4 antibody, by flow cytometry. Gemcitabine increased FasL mRNA and total protein expression, the percentage of H292 cells bearing membrane‐bound FasL (mFasL) and of mFasL‐positive apoptotic H292 cells, as well as caspase‐8 and caspase‐3 cleavage. Moreover, gemcitabine increased CH11‐induced caspase‐8 and caspase‐3 cleavage and proteolytic activity. Cytotoxicity of LAK cells and pleural fluid lymphocytes was increased against gemcitabine‐treated H292 cells and was partially inhibited by ZB4 antibody. These results demonstrate that gemcitabine: (i) induces up‐regulation of FasL in lung cancer cells triggering cell apoptosis via an autocrine/paracrine loop; (ii) induces a Fas‐dependent apoptosis mediated by caspase‐8 and caspase‐3 activation; (iii) enhances the sensitivity of lung cancer cells to cytotoxic activity of LAK cells and malignant pleural fluid lymphocytes, partially via Fas/FasL pathway. Our data strongly suggest an active involvement of the Fas/FasL system in gemcitabine‐induced lung cancer cell killing.     

Germ cell apoptosis in autoimmune orchitis: involvement of the Fas-FasL system

PROBLEM: The aim of this study was to determine the mechanism of germ cell death in experimental autoimmune orchitis (EAO) and the involvement of the Fas-FasL system in this process. METHOD OF STUDY: The EAO was induced in rats by immunization with testis homogenate and adjuvants. Apoptosis was studied by light microscopy, in situ end labeling of apoptotic DNA and DNA fragmentation techniques. Fas, FasL and caspase 3 expression was detected by immunohistochemistry. RESULTS: In rats with orchitis the number of Fas+ and FasL+ apoptotic germ cells increased from day 50, when the lesion develops, to 150 days, and correlates with the degree of testicular damage. Most spermatocytes expressing Fas were apoptotic. Many Fas+ germ cells were also immunoreactive for FasL. Moreover, these cells also expressed caspase 3. CONCLUSIONS: In rats with EAO germ cell death occurs through an apoptotic mechanism preceding germ cell sloughing. Immunohistochemical data suggest that the Fas-FasL system mediates germ cell apoptosis in an autocrine and/or paracrine way.     

Induction of macrophage cell‐cycle arrest and apoptosis by humic acid

Humic acid (HA) in well water is associated with Blackfoot disease and various cancers. Previously, we reported that acute humic acid exposure (25–200 µg/mL for 24 hr) induces inflammation in RAW264.7 macrophages. In this study, we observed that prolonged (72 hr) HA exposure (25–200 µg/mL) induces cell‐cycle arrest and apoptosis in cultured RAW264.7 cells. We also observed that exposing macrophages to HA arrests cells in the G₂/M phase of the cell cycle by reducing cyclin A/B₁, Cdc2, and Cdc25C levels. Treating macrophages with HA triggers a sequence of events characteristic of apoptotic cell death including loss of cell viability, morphological changes, internucleosomal DNA fragmentation, sub‐G₁ accumulation. Molecular markers of apoptosis associated with mitochondrial dysfunction were similarly observed, including cytochrome c release, caspase‐3 or caspase‐9 activation, and Bcl‐2/Bax dysregulation. In addition to the mitochondrial pathway, HA‐induced apoptosis may also be mediated through the death receptor and ER stress pathways, as evidence by induction of Fas, caspase‐8, caspase‐4, and caspase‐12 activity. HA also upregulates p53 expression and causes DNA damage as assessed by the comet assay. These findings yield new insight into the mechanisms by which HA exposure may trigger atherosclerosis through modulation of the macrophage‐mediated immune system. Environ. Mol. Mutagen. 55:741–750, 2014. © 2014 Wiley Periodicals, Inc.     

Evidence for a Novel, Caspase-8-Independent, Fas Death Domain-Mediated Apoptotic Pathway

Certain caspase-8 null cell lines demonstrate resistance toFas-induced apoptosis, indicating that the Fas/FasL apoptoticpathway may be caspase-8-dependent. Some reports, however, haveshown that Fas induces cell death independent of caspase-8. Herewe provide evidence for an alternative, caspase-8-independent,Fas death domain-mediated apoptotic pathway. Murine 12B1-D1 cellsexpress procaspase-3, -8, and -9, which were activated upon thedimerization of Fas death domain. Bid was cleaved andmitochondrial transmembrane potential was disrupted in thisapoptotic process. All apoptotic events were completely blockedby the broad-spectrum caspase inhibitor Z-VAD-FMK, but not byother peptide caspase inhibitors. Cyclosporin A (CsA), whichinhibits mitochondrial transition pore permeability, blockedneither pore permeability disruption nor caspase activation.However, CsA plus caspase-8 inhibitor blocked all apoptoticevents of 12B1-D1 induced by Fas death domain dimerization. Ourdata therefore suggest that there is a novel,caspase-8-independent, Z-VAD-FMK-inhibitable, apoptotic pathway in12B1-D1 cells that targets mitochondria directly.     

Inhibition of proteasome activity in Gleditsia sinensis fruit extract-mediated apoptosis on human carcinoma cells

The anomalous fruit extract of Gleditsia sinensis (GSE) was shown to possess anticancer potential on various solid tumour and leukaemia cell lines in vitro. We have recently demonstrated that the mitochondrial-dependent apoptotic pathway including mitochondrial membrane potential depolarization, changes in the level of reactive oxygen species and activation of caspase 3 were recruited in GSE-induced apoptosis. Whether receptor-dependent APO-1/Fas apoptotic pathway is also involved remains uncertain. Using two solid tumour cell lines, the HepG2 hepatoblastoma carcinoma cells and MDA-MB231 breast cancer cells, we demonstrated that the Fas ligand and Fas receptor protein levels did not have significant variation after GSE incubation. Caspase 8 activity increased only weakly when compared with that of caspase 3. The chrymotrypsin-like activity of proteasome was partially inhibited up to 30-40% when compared with the untreated control. Taken together, we believe that GSE- mediated apoptosis on HepG2 and MDA-MB231 carcinoma cells is mainly dictated by the mitochondrial-dependent pathway while inhibition of proteasome activity may also be involved in GSE-induced apoptosis.     

The involvement of caspases in the CD95(Fas/Apo-1)- but not swelling-induced cellular taurine release from Jurkat T-lymphocytes

Following a delay of 45 min, stimulation of the CD95 (Fas/Apo-1)-receptor in Jurkat T-lymphocytes leads to the release of the osmolyte taurine, an event coinciding with apoptotic cell shrinkage. The present study has been performed to elucidate the cellular mechanisms involved in CD95-induced taurine release as compared to swelling-induced taurine release, and to explore whether taurine modifies apoptotic DNA fragmentation and cell shrinkage. Taurine release stimulated by osmotic cell swelling is insensitive to the tyrosine kinase inhibitor herbimycin A and the caspase inhibitor z-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD) but is blunted in the absence of extracellular Ca2+. Conversely, the Ca2+ ionophore ionomycin stimulates taurine release. However, the taurine release following CD95 stimulation is not paralleled by an increase of cytosolic Ca2+ and not inhibited by complexation of extracellular Ca2+. None of herbimycin A, the phosphatase inhibitor vanadate, spingomyelinase or Lck56 deficiency prevent CD95-induced taurine release. In contrast, the caspase inhibitor zVAD, but not the caspase inhibitor Ac-Tyr-Val-Ala-Asp-chloromethylketone (YVAD), almost abolishes CD95-induced taurine release. Both caspase inhibitors blunt CD95-induced cell shrinkage and DNA fragmentation, zVAD being more effective than YVAD. Preloading of the cells with 40 mM taurine but not with 40 mM mannitol significantly inhibits CD95-induced DNA fragmentation (by 28%) and apoptotic cell shrinkage (by 25%). In conclusion, CD95-receptor triggering leads to caspase-dependent stimulation of cellular taurine release, which facilitates, but is not sufficient for, the triggering of apoptotic DNA fragmentation and cell shrinkage.     

Treatment of multiple sclerosis patients with interferon-beta primes monocyte-derived macrophages for apoptotic cell death.

Although interferon (IFN)-beta has shown a significant clinical benefit in multiple sclerosis (MS), its mechanism of action remains unclear. We found that IFN-beta treatment of patients with MS resulted in a significant increase in apoptotic cell death (measured by annexin V staining and nuclear fragmentation) of monocyte-derived macrophages, as compared with cells derived from patients before treatment. Stimulation of the cells with IFN-beta in vitro resulted in an even further increase of annexin V binding, as well as increased Fas (CD 95, APO-1) expression. However, no increased Fas expression, apoptotic monocytes, or monocytopenia were observed upon in vivo treatment. This indicates that IFN-beta does not deliver a death signal to monocytes but rather primes for subsequent macrophage apoptosis upon activation or differentiation.     

Apoptosis of tubular epithelial cells in glycogen nephrosis during diabetes

The important problem of the fate of glycogen-accumulating clear cells in glycogen nephrosis is still unsettled. In this study, we examine whether apoptosis plays a relevant role in the development of diabetic glycogen nephrosis and explore the involvement of the Fas/Fas-L system and the activation of the caspase cascade. Diabetes was induced in rats by streptozotocin injection. Glycogen-accumulating clear cells were identified in renal tissues of hyperglycemic rats. They were found to be concentrated in the thick ascending limbs and distal tubules. Large cellular glycogen accumulations were confirmed by biochemical assays and enzyme-gold cytochemistry. Clear cells displayed apoptotic features such as Annexin V binding, nuclear TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling), and the simultaneous occurrence of Fas, Annexin V, and TUNEL positivity. Western blot analysis demonstrated enhanced expression of Fas receptor/ligand and the activation of the caspase cascade in these cells because cleaved forms of the caspase-3, -8, and -9 were detected. Furthermore, active caspase-3 was located in nuclei by immunoelectron microscopy. Our results indicate that epithelial cells in thick ascending limbs and distal tubules that develop glycogen nephrosis in response to hyperglycemia undergo Fas/Fas-L mediated cell death. Thus, apoptosis could be playing a significant role in renal epithelial cell deletion during diabetes.     

Resistance to Fas-mediated apoptosis is restored by cycloheximide through the downregulation of cellular FLIPL in NK/T-cell lymphoma

Extranodal NK/T-cell lymphoma (NKTL), nasal type, is a highly aggressive neoplasm and is strongly associated with Epstein-Barr virus (EBV). In this study, we demonstrate that EBV-positive NKTL cell lines, namely, Hank-1, NK-YS, and NK-L, are resistant to Fas-mediated apoptosis induced by anti-Fas antibodies despite high levels of Fas surface expression and no mutation in the Fas gene. Fas stimulation of Hank-1 and NK-YS cells showed little processing of caspase 8, caspase 3, or bid, although the proximal signaling molecules of the death-inducing signaling complex, namely, Fas, Fas-associated protein with a death domain, caspase 8, and bid were present in these cells. Consistent with previous reports on the hypermethylation of death associated protein (DAP) kinase in NKTLs, the promoter of DAP kinase was methylated and its mRNA not detected in Hank-1 cells. However, the restoration of DAP kinase expression by 5-aza-2'-deoxycytidine did not sensitize Hank-1 to Fas-mediated apoptosis, indicating that DAP kinase deficiency does not contribute to resistance to Fas-mediated apoptosis. Since etoposide-induced apoptosis involved caspase 3 activation in Hank-1 and NK-YS cells, the caspase 3-dependent apoptotic machinery appears to be intact. Interestingly, cotreatment of Hank-1 with cycloheximide, a protein synthesis inhibitor, markedly sensitized cells to Fas-mediated apoptosis along with caspase 8 activation and c-FLIP(L) (cellular FLICE inhibitory protein long form) downregulation. Moreover, immunohistochemistry on paraffin-embedded tissue revealed c-FLIP expression in 39% (14 of 36) of NKTL patients. Taken together, these findings indicate that c-FLIP(L)-mediated resistance to Fas contributes to the development and progression of NKTLs. This study also suggests that agents capable of downregulating c-FLIP(L) could be used to treat NKTL.     

Fas and activated caspase 8 in normal, Alzheimer and multiple infarct brains

Using immunohistochemistry, Fas and caspase 8 positive sites were localized in the brains of Alzheimer patients and those with multiple infarcts as well as age-matched normal. The frontal, occipital and hippocampal regions were dissected out from these patients and normal individuals shortly after death. Positive Fas neurons were found in all these regions of normal individuals and Alzheimer patients, but not in the brains of patients with multiple infarct. Activated caspase 8 protein was found only in the brains of Alzheimer patients and not in the other groups. Plaques in the Alzheimer patients were positive for Fas and activated caspase 8. The former was localized in the membrane and the inside of the plaque whereas activated caspase 8 was only present in the interior of the plaque, as revealed by confocal microscopy. Our study shows that caspase 8 was activated in the Alzheimer brain and the presence of Fas and activated caspase 8 points to a possibility that at least some plaques were of intracellular origin as Fas was a cell membrane receptor and caspase 8 was a intracellular enzyme downstream to Fas. Furthermore, we had confirmed that in most neurons Fas and caspase 8 did not exist concomitantly and that the glial cells (astrocytes) did not express caspase 8 in Alzheimer patients.     

雷公藤红素诱导CEM-6T细胞凋亡的机制研究

在已经证明雷公藤红素能诱导人T淋巴细胞株CEM 6T细胞凋亡的基础上 ,进一步探讨此凋亡过程的机制。本项目研究雷公藤红素诱导CEM 6T细胞凋亡过程中Fas/FasL、ICEmRNA的变化以及ICE抑制剂、磷酸酶抑制剂对凋亡的影响。结果发现 ( 1)CEM 6T细胞表达Fas,不表达FasL ,雷公藤红素处理不能改变这一情况 ;( 2 )雷公藤红素不能改变ICEmRNA的表达水平 ,但ICE抑制剂Ac YVAD CHO能使雷公藤红素诱导CEM 6T的凋亡率下降 ;( 3) 1 5 μmol/L磷酸酶抑制剂okadaicacid能使凋亡率下降。提示雷公藤红素诱导CEM 6T细胞凋亡不依赖Fas/FasL ,而与细胞内原已存在的ICE有关 ,蛋白去磷酸化参与了此凋亡过程     

T细胞表达Fas用于评价系统性红斑狼疮活动性和疗效的价值

目的：流式细胞术检测系统性红斑狼疮(SLE)患者T细胞表面Fas表达水平，探讨其用于评价疾病活动指数和疗效的价值。方法:对36例活动期SLE患者和18名正常人群，通过流式细胞仪检测T细胞Fas表达和凋 亡率。对SLE患者分别给予泼尼松、甲泼尼龙、环磷酰胺冲击治疗，在入院3 d内、出院时（平均住院天数为22.6 d）、出院后4周分别检测T细胞Fas表达（Fas+T）。结果:活动期SLE患者T细胞表面Fas表达与T细胞凋亡率和SLEDAI之间，具有明显正相关P<0.01），皮质类固醇或免疫抑制剂治疗活动期SLE患者后，出院时T细胞表面Fas 表达（Fas+T）明显升高；出院后4周复诊时呈下降趋势。结论:SLE 患者T细胞表面Fas表达上调,由Fas介导的T细胞凋亡增强,刺激机体产生抗dsDNA等多种自身 抗体,可能是SLE免疫功能紊乱的主要原因。T细胞表面Fas密度可能是评价SLE疾病活动性和 临床疗效的主要参数。     

T-cell and neuronal apoptosis in HIV infection: implications for therapeutic intervention

The pathogenesis of HIV infection involves the selective loss of CD4+ T cells contributing to immune deficiency. Although loss of T cells leading to immune dysfunction in HIV infection is mediated in part by viral infection, there is a much larger effect on noninfected T cells undergoing apoptosis in response to activation stimuli. In the subset of patients with HIV dementia complex, neuronal injury, loss, and apoptosis are observed. Viral proteins, gp120 and Tat, exhibit proapoptotic activities when applied to T cell and neuronal cultures by direct and indirect mechanisms. The pathways leading to cell death involve the activation of one or more death receptor pathways (i.e., TNF-alpha, Fas, and TRAIL receptors), chemokine receptor signaling, cytokine dysregulation, caspase activation, calcium mobilization, and loss of mitochondrial membrane potential. In this review, the mechanisms involved in T-cell and neuronal apoptosis, as well as antiapoptotic pathways potentially amenable to therapeutic application, are discussed.     

Antiproliferative and apoptosis-inducing activity of Brucea javanica extract on human carcinoma cells

We have recently demonstrated the antiproliferative and apoptotic activities of herbal traditional Chinese medicines, including the analomous fruit extract of Gleditsia sinensis, the fresh juice of Scutellaria barbata and the warmed water extract of Radix Sophorae Tonkinensis on a series of human carcinoma cells. Here, we further report the potential anti-cancer activity of the warmed water extract of Brucea javanica (BJE). Four cancer cell lines, including A549 non-small cell lung cancer, Hep3B hepatocellular carcinoma, MDA-MB231 breast cancer and SLMT-1 oesophageal squamous cell carcinoma, were incubated with BJE and strong apoptotic induction was observed under inverted microscopic investigation for all of the four cell lines tested. Using the MDA-MB231 breast cancer cell line as an experimental model, additional analyses supported the hypothesis that the mitochondrial membrane potential depolarization pathway was induced by BJE. The APO-1/Fas receptor death induction pathway was not activated under the influence of BJE, as studied by staining with Fas ligand and Fas receptor specific antibodies. Accordingly, only weak activation of caspase 8 was observed upon BJE treatment. On the other hand, caspase 3 activity was stimulated up to five-fold in BJE-treated cells compared to untreated controls. Oligonucleosomal DNA fragmentation formation was detected by labelling the nucleic acid ladders with TdT-mediated dUTP nick end labelling. Collectively, BJE-induced cancer cell death proceeds through a mitochondrial dependent pathway associated with caspase 3 activation.     

Proliferation and death of cultured fetal neocortical neurons: effects of ethanol on the dynamics of cell growth

Neuronal number in the mature CNS is determined by the balance of cell proliferation and death. The effects of ethanol on cell proliferation and death were examined in primary cultures of neocortical neurons derived from 16-day-old rat fetuses. The cells were treated with ethanol (0 or 400 mg/dl) and examined for (1) immunohistochemical identity, (2) cell cycle kinetics using a cumulative bromodeoxyuridine labeling technique, (3) viable cell number via a trypan blue assay, and (4) the incidence of cell death with terminal deoxy-nucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and caspase 3 immunhistochemistry. After two days in culture, most (>85%) cells expressed a neuron-specific antigen(s) whether or not ethanol was added to the culture medium. Ethanol affected the proliferation of the cultured cells, e.g., the length of the cell cycle was greater in the ethanol-treated cells than in controls. The number of trypan blue-negative (viable) cells was profoundly decreased by ethanol exposure. This decrease was accompanied by increases in the frequencies of TUNEL- and caspase 3-positive cells and of cells exhibiting nuclear condensations. Thus, ethanol decreases the number of viable cells in vitro by slowing cell proliferation and increasing the incidence of cell death. The expression of the death indices in untreated cultures is most consistent with a single (apoptotic) pathway of cell death, rather than simultaneous apoptotic and necrotic modes of death. Furthermore, it appears that ethanol initiates an apoptotic death among cultured cortical neurons.     

Participation of the Fas and Fas ligand systems in apoptosis during atrophy of the rat submandibular glands

Most acinar cells and some duct cells undergo apoptosis during atrophy of the submandibular gland. The present study was designed to elucidate whether Fas and its receptor ligand (FasL) are involved during apoptotic atrophy of the gland. The excretory duct of the right submandibular gland of rats was doubly ligated with metal clips from 1 to 14 days for induction of gland atrophy. Control rats were untreated. Fas and FasL expression in the atrophied submandibular gland was detected using immunohistochemistry (IHC) and Western immunoblot. Expression of activated caspase 8 and activated caspase 3 was also detected with IHC. Fas-positive acinar and duct cells and FasL-positive duct cells increased in the atrophic glands at 3 and 5 days after duct ligation when apoptotic cells were commonly observed. Thereafter, Fas- and FasL-positive cells declined in number. Patterns of expression of Fas and FasL using Western immunoblots concurred with the IHC results. Activated caspase 8-positive cells were present at every time interval but peaked at 3 and 5 days following duct ligation. The cells showing immunoreaction for activated caspase 3 first appeared on day 3, with the peak in apoptosis, after which they decreased. The results indicate that the Fas/FasL systems likely play an important role in apoptotic pathways during atrophy of the submandibular gland.     

Fas/CD95-mediated apoptosis of type II cells is blocked by Toxoplasma gondii primarily via interference with the mitochondrial amplification loop

The intracellular protozoan Toxoplasma gondii induces persistent infections in various hosts and is an important opportunistic pathogen of humans with immature or deficient immune responses. The ability to survive intracellularly largely depends on the blocking of different proapoptotic signaling cascades of its host cell. Fas/CD95 triggers an apoptotic cascade that is crucial for immunity and the outcome of infectious diseases. We have determined the mechanism by which T. gondii counteracts death receptor-mediated cell death in type II cells that transduce Fas/CD95 ligation via caspase 8-mediated activation of the mitochondrial amplification loop. The results showed that infection with T. gondii significantly reduced Fas/CD95-triggered apoptosis in HeLa cells by inhibiting the activities of initiator caspases 8 and 9 and effector caspase 3/7. Parasitic infection dose dependently diminished cleavage of caspase 8, the BH3-only protein Bid, and the downstream caspases 9 and 3. Importantly, interference with Fas/CD95-triggered caspase 8 and caspase 3/7 activities after parasitic infection was largely dependent on the presence of caspase 9. Within the mitochondrial amplification loop, T. gondii significantly inhibited the Fas/CD95-triggered release of cytochrome c into the host cell cytosol. These results indicate that T. gondii inhibits Fas/CD95-mediated apoptosis in type II cells primarily by decreasing the apoptogenic function of mitochondria.     

Activated cytotoxic T cells and NK cells in severe sepsis and septic shock and their role in multiple organ dysfunction

To evaluate the role of activated cytotoxic cells in patients with severe sepsis (n = 32) or septic shock (n = 8), direct (granzymes A and B) as well as indirect markers (cytokines) for cytotoxic cell activation were measured. Elevated IL-12p40 levels had been detected in 58% of the sepsis patients, whereas only a few had detectable TNF-alpha, IFN-gamma, or IL-12p70 levels. Granzymes A and B levels were elevated in 42.5% and 22.5%, respectively. IL-12p40 inversely correlated with disease severity. Inflammatory parameters (IL-6) and coagulation markers were significantly lower and higher, respectively, in patients with elevated IL-12p40 and granzyme B levels, as compared to those with normal levels. Elevation of granzyme A directly correlated with the increase of apoptotic markers. Activated cytotoxic cells reflected by elevated granzymes A and/or B were found in 50% of our sepsis patients. This group showed a higher mortality and a worse organ function.