Amniotic Fluid Proteasome and Immunoproteasome in the Setting of Intra-Amniotic Infection, Inflammation, and Preterm Birth.

Preterm birth is an important determinant of neonatal morbidity and mortality and intra-amniotic infection (IAI) and inflammation play a causative role. The constitutive proteasome and immunoproteasome are key players in maintenance of proteostasis and their alteration outside pregnancy has been linked to pathogenesis of numerous inflammatory diseases. Our goal was to evaluate the levels, activities, and potential origin of amniotic fluid (AF) proteasome in women with preterm birth induced by infection and/or inflammation. Total proteasome and immunoproteasome concentrations were measured in AF retrieved by trans-abdominal amniocentesis from 155 pregnant women. Proteasome activities were measured with fluorogenic substrates targeting caspase-like (CAS-L), trypsin-like (TRY-L), or chymotrypsin-like (CHE-L) lytic activities. We found that IAI significantly upregulated AF concentrations of total proteasome and of the immunoproteasome (P<0.001 for both) with no differences based on gestational age. Based on substrate preference and profile of pharmacologic inhibition, we identified the CHE-L activity of the immunoproteasome as the primary lytic activity upregulated in AF of pregnancies complicated by IAI. When compared with matched maternal blood and cord blood, proteasome activity was by far the highest in AF and this was further elevated in IAI. Western blot confirmed ß5 (PSMB5) and ß5i (PSMB8) subunits of the constitutive proteasome and immunoproteasome are present in AF and IHC staining of fetal membranes pointed to chorio-decidua as a potential source. In conclusion, IAI is associated with increased AF immunoproteasome activity that by analogy with other inflammatory diseases may generate antigenic oligopeptides and may play a role in triggering preterm birth.

Daily monitoring of vaginal interleukin 6 as a predictor of intraamniotic inflammation after preterm premature rupture of membranes - a new method of sampling studied in a prospective multicenter trial.

OBJECTIVES: (A) To introduce a new technique for vaginal fluid sampling (biocompatible synthetic fiber sponge) and (B) evaluate the collected vaginal fluid interleukine-6 (IL-6vag)-concentration as a new diagnostic tool for daily monitoring of intrauterine inflammation after preterm premature rupture of membranes (PPROM). Secondary objectives were to compare the potential to predict an intrauterine inflammation with established inflammation parameters (e.g., maternal white blood cell count). METHODS: This prospective clinical case-control diagnostic accuracy multicenter study was performed with women after PPROM (gestational age 24.0/7 - 34.0/7 weeks). Sampling of vaginal fluid was performed once daily. IL-6vag was determined by electrochemiluminescence-immunoassay-kit. Neonatal outcome and placental histology results were used to retrospectively allocate the cohort into two subgroups: 1) inflammation and 2) no inflammation (controls). RESULTS: A total of 37 cases were included in the final analysis. (A): Measurement of IL-6 was successful in 86% of 172 vaginal fluid samples. (B): Median concentration of IL-6vag in the last vaginal fluid sample before delivery was significantly higher within the inflammation group (17,085 pg/mL) compared to the controls (1,888 pg/mL; p=0.01). By Youden's index an optimal cut-off for prediction an intrauterine inflammation was: 6,417 pg/mL. Two days before delivery, in contrast to all other parameters IL-6vag remained the only parameter with a sufficient AUC of 0.877, p<0.001, 95%CI [0.670-1.000]. CONCLUSIONS: This study established a new technique for vaginal fluid sampling, which permits assessment of IL-6vag concentration noninvasively in clinical daily routine monitoring.

Cytotrophoblasts suppress macrophage-mediated inflammation through a contact-dependent mechanism.

PROBLEM: Gestational membrane (GM) infection provokes inflammation and can result in preterm prelabor rupture of membranes (PPROM). The choriodecidual layer of the GM includes decidual stromal cells (DSC), cytotrophoblasts (CTB), and macrophages (Mφ). Our laboratory has previously shown that DSCs suppress Mφ TNF-α production through secreted prostaglandin E2 . We hypothesized that CTBs would also inhibit Mφ cytokine expression through secreted mediators. METHOD OF STUDY: THP.1 Mφ-like cells with an NF-κB reporter construct or human blood monocyte-derived Mφ were co-cultured with the Jeg3 CTB cell line or primary human CTBs and challenged with group B streptococcus (GBS) or Toll-like receptor (TLR) agonists. Conditioned medium generated from CTB cultures was applied to Mφ cultures before infection or treatment. Alternatively, CTBs were co-incubated with, but physically separated from, Mφ and GBS or TLR-stimulated. NF-κB was assessed via alkaline phosphatase assay, and proinflammatory mediators were assessed by qRT-PCR and ELISA. RESULTS: CTBs suppressed GBS- or TLR-stimulated Mφ NF-κB activity, and TNF-α and MMP9 production. Direct physical contact between CTBs and Mφ was required for full immunosuppression. Immunosuppression could be overcome by increasing the ratio of Mφ to CTB. CONCLUSIONS: CTBs limit Mφ NF-κB activation and production of TNF-α and MMP9 through an as-yet unknown, cell-to-cell contact-mediated mechanism. This suppression is distinct from the PGE2 -mediated Mφ TNF-α suppression by DSC, suggesting that DSCs and CTBs regulate Mφ inflammation through distinct mechanisms. How Mφ integrates these signals in an intact GM will be paramount to determining causes and prevention of PPROM.

Alpha-2-macroglobulin from circulating exosome-like vesicles is increased in women with preterm pregnancies.

Preterm labor (PTL) and Preterm Premature Rupture of Membranes (PPROM) impose substantial morbimortality on mothers and newborns. Exosomes act in intercellular communication carrying molecules involved in physiopathological processes. Little is known about exosomal proteins in prematurity. Our aim was to evaluate the protein expression of hemopexin, C1 inhibitor (C1INH) and alpha-2-macroglobulin (A2M) from circulating exosomes of women with PTL and PPROM. Plasma was obtained from PTL, PPROM, Term in labor and Term out of labor (T) patients, exosomes were isolated by ultracentrifugation, then lysed and the proteins quantified. Western Blot (WB) and Nanoparticle Tracking Analysis (NTA) were performed. Data were compared by Kruskal-Wallis, unpaired T-test and one-way ANOVA. WB and NTA confirmed exosome isolation (concentration: 4.3 × 1010 particles/ml ± 1.9 × 1010). There was no difference regarding hemopexin or C1INH expression between the groups. For A2M, the fold change was significantly higher on preterm groups when compared to term groups (1.07 ± 0.30 vs. 0.42 ± 0.17, p < 0.0001). Higher levels of A2M in circulating exosomes are linked to preterm pregnancies. sEV are strong candidates to intermediate maternal-fetal communication, carrying preterm labor-related immunomodulatory proteins.

Cellular immune responses in amniotic fluid of women with preterm prelabor rupture of membranes.

Background Preterm birth is the leading cause of perinatal morbidity and mortality. Preterm prelabor rupture of membranes (pPROM) occurs in 30% of preterm births; thus, this complication is a major contributor to maternal and neonatal morbidity. However, the cellular immune responses in amniotic fluid of women with pPROM have not been investigated. Methods Amniotic fluid samples were obtained from women with pPROM and a positive (n = 7) or negative (n = 10) microbiological culture. Flow cytometry was performed to evaluate the phenotype and number of amniotic fluid leukocytes. The correlation between amniotic fluid immune cells and an interleukin-6 (IL-6) concentration or a white blood cell (WBC) count in amniotic fluid was calculated. Results Women with pPROM and a positive amniotic fluid culture had (1) a greater number of total leukocytes in amniotic fluid, including neutrophils and monocytes/macrophages and (2) an increased number of total T cells in amniotic fluid, namely CD4+ T cells and CD8+ T cells, but not B cells. The numbers of neutrophils and monocytes/macrophages were positively correlated with IL-6 concentrations and WBC counts in amniotic fluid of women with pPROM. Conclusion Women with pPROM and a positive amniotic fluid culture exhibit a more severe cellular immune response than those with a negative culture, which is associated with well-known markers of intra-amniotic inflammation.

The role of innate immunity in spontaneous preterm labor: A systematic review.

BACKGROUND: Immunoinflammatory response by innate immunity components is a field with increasing interest in understanding the mechanisms behind preterm labor (PTL). OBJECTIVES: Systematic review of the role of innate immunity in spontaneous PTL. STUDY DESIGN: PubMed, Scopus, ClinicalTrials.gov and Web of Science were searched using pregnancy AND innate OR toll-like OR natural-killer OR dendritic AND delivery OR premature OR rupture of membranes. MAIN OUTCOME MEASURES: All article titles and abstracts were evaluated by two individuals, based in strict predefined inclusion criteria. For relevant studies, title, abstract, and full text were assessed to identify PTL and innate immunity studies, excluding multiple pregnancies, cervical insufficiency and indicated PTL. RESULTS: From 894 articles evaluated, 101 full texts articles were assessed independently. For this systematic review 44 studies were finally included. Toll-like receptors 2 and 4 mediated immune dysfunction and inflammation can result in PTL. Moreover, PTL is linked to high levels of CD14+ monocytes; neutrophils seem important in inflammation-associated PTL and in pathological preterm premature rupture of membranes. Besides, decidual natural-killer cells and premature activation of dendritic cells may also participate in the etiology of PTL. Finally, dysregulation of maternal complement might increase the risk of PTL, characterized by high levels of innate lymphoid cells 2 and 3. CONCLUSIONS: Further research is warranted to ascertain the precise role of innate immunity in PTL. Nonetheless, our results indicate that Toll-like receptors, monocytes, natural-killer cells, dendritic cells and complement have significant roles in PTL.

Role of NF-κB/GATA3 in the inhibition of lysyl oxidase by IL-1ß in human amnion fibroblasts.

Preterm premature rupture of membranes (pPROMs) account for one-third of preterm births, a leading cause of neonatal death. Understanding the mechanism of membrane rupture is thus of clinical significance in the prevention of preterm birth. Parturition at both term and preterm is associated with increased abundance of proinflammatory cytokines in the fetal membranes regardless of the presence of infection, which is believed to induce rupture of membranes through activation of the matrix metalloproteinases. It remains unknown whether there are any alternative mechanisms underpinning proinflammatory cytokine-induced rupture of membranes. Here we showed that there were reciprocal increases in interleukin-1ß (IL-1ß) and decreases in lysyl oxidase (LOX), a collagen crosslinking enzyme, in the human amnion tissue following spontaneous rupture of membrane at term and pPROM. Studies using human amnion tissue explants revealed that IL-1ß inhibited the expression of LOX, which can be reproduced in cultured human amnion fibroblasts. Mechanistic study revealed that IL-1ß inhibited LOX expression through activation of p38 and Erk1/2 mitogen-activated protein kinase pathways, which resulted in the phosphorylation of the nuclear factor kappa light-chain enhancer of activated B (NF-κB) cell subunit p65 as well as GATA binding protein 3 (GATA3). Subsequently, activated NF-κB interacted with GATA3 at the NF-κB binding site of LOX promoter to inhibit its expression. Conclusively, this study has revealed an alternative mechanism that IL-1ß may contribute to the rupture of membranes by attenuating collagen crosslinking through downregulation of LOX expression in amnion fibroblasts.

IL-10 and pregnancy complications.

PURPOSE OF INVESTIGATION: Successful pregnancy depends on the ability of the mother's immune system to undergo a process of immunoregulation in order to tolerate the fetus, and also to create and sustain a nurturing environment during all the stages of pregnancy. Several reports point to interleukin 10 (IL-10) as being vital for normal pregnancy, and low IL-10 levels as being associated with preg- nancy complications. This study aimed to compare IL-10 levels in normal and complicated pregnancy conditions. MATERIAL AND METHODS: The authors compared levels of IL-10 produced upon stimulation of maternal peripheral blood mononuclear cells (PBMC) from women at different stages of normal gestation with those produced by women with pregnancy complications, such as recurrent spontaneous miscarriage (RSM), preterm delivery (PTD), premature rupture of fetal membranes (PROM), pre-eclampsia, and intrauterine fetal growth retardation (IUGR). RESULTS: Median levels of IL-10 are statistically significantly lower in pathological conditions as com- pared to matching gestational ages of normal pregnancy. CONCLUSION: Healthy pregnancy is associated with higher levels of IL-10, while pathologic pregnancies are associated with lower levels of IL-10.

Predictive value of maternal serum NF-κB p65 and sTREM-1 for subclinical chorioamnionitis in premature rupture of membranes.

PROBLEM: The aim of this study was to investigate the levels of nuclear factor kappa B-p65 (NF-κB p65) and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) in maternal blood with premature rupture of membranes (PROM) and to assess their values for prediction of subclinical chorioamnionitis. METHOD: NF-κB p65 and sTREM-1 levels were measured in maternal blood and cord blood by fluorescence quantitative RT-PCR assay. According to the placental membranes pathological examination, pregnant women with PROM were divided into chorioamnionitis group (n=28) and non-chorioamnionitis group (n=22). RESULTS: In the PROM group,the NF-κB p65 and sTREM-1 levels in maternal blood were significantly higher in women with chorioamnionitis than women without chorioamnionitis (P<.05). The cutoff value of maternal NF-κB p65, sTREM-1, C-reactive protein (CRP), and WBC level were 6.73, 2.93, 6.75 mg/L, and 10.8×10(9) /L, respectively, through analysis of the area under the ROC curve (AUC). The optimal combination test was detection of maternal blood NF-κB p65 and CRP levels, which resulted in a sensitivity of 89.3% and a specificity of 72.7% for the prediction of subclinical chorioamnionitis. CONCLUSION: Combined measurements of maternal NF-κB p65 and CRP levels may be used as early biological indicators that predict subclinical chorioamnionitis in premature rupture of membranes.

Expression of lymphocyte activation markers of preterm neonates is associated with perinatal complications.

BACKGROUND: Inappropriate activation of T lymphocytes plays an important role in perinatal complications. However, data on T lymphocyte activation markers of preterm infants is scarce. We investigated the association between gender, gestational and postnatal age, preeclampsia (PE), premature rupture of membranes (PROM) as well as prenatal steroid treatment (PS) and the frequency of activated T lymphocyte subsets (HLA-DR+, CD69+, CD25+, CD62L+) and major T lymphocyte subpopulations (CD4, CD8, Th1, Th2, naïve, memory) in peripheral blood during the first postnatal week in preterm infants. RESULTS: Cord blood and peripheral blood samples were collected from 43 preterm infants on the 1st, 3rd, and 7th days of life. We assessed the frequency of the above T lymphocyte subsets using flow cytometry. The 'mixed effect model' was used to analyze the effects of clinical parameters on T lymphocyte markers. The frequency of CD25+ T lymphocytes was higher in PROM. The frequency of CD4+ and CD8+ cells and the CD4+/CD8+ cell ratio was decreased in PE. The frequency of CD62L+ T lymphocytes was higher in male compared with female infants. PS did not affect the frequency of the investigated markers. CD4+ CD25+ cells had a lower frequency at birth than on day 7. Th2 lymphocytes had a lower frequency on postnatal days 1 and 3 when compared to day 7. CONCLUSIONS: Our observations indicate that alterations affecting the expression of T lymphocyte activation markers are associated with the above factors and may play a role in the development of perinatal complications.

Serum concentrations of soluble B7-H4 in early pregnancy are elevated in women with preterm premature rupture of fetal membranes.

PROBLEM: To determine the association between maternal soluble B7-H4 (sB7-H4) and the preterm premature rupture of the amniotic membranes (pPROM), the blood serum concentration levels of sB7-H4 were studied. METHOD OF STUDY: Maternal serum levels of sB7-H4 were determined with enzyme-linked immunosorbent assay (ELISA) in patients between 11 and 13 weeks' gestation who later on in the pregnancy developed pPROM (n=21), premature rupture of the amniotic membranes at term (n=18), and in control group (n=27). RESULTS: The highest serum levels of sB7-H4 were found in patients who developed pPROM. An OR of 1.39 (95%-CI: 1.17-1.77; P=.002) per ng/mL sB7-H4 indicated an increased risk for developing pPROM, with some predictive ability to discriminate between pPROM cases and controls (AUC=.81). CONCLUSION: Increased serum levels of sB7-H4 in early pregnancy in pPROM cases may indicate the dynamics of the immune response at the feto-maternal interface and, thus, may serve as a predictive marker for this pregnancy complication.

Soluble HLA-G concentrations in maternal blood and cervical vaginal fluid of pregnant women with preterm premature rupture of membranes.

OBJECTIVE: To evaluate soluble HLA-G (sHLA-G) concentrations in maternal blood serum and cervical vaginal fluid in pregnancies complicated by preterm premature rupture of membranes (PPROM) compared to controls. STUDY DESIGN: Case-control study of 24 women with PPROM and 40 controls. MAIN OUTCOME MEASURES: Vaginal and serum sHLA-G and IL-6 concentrations. FINDINGS: Women with PPROM had significantly higher serum and vaginal sHLA-G concentrations compared to controls (respectively median 31.48U\ml versus 13.9U\ml p<0.001 and 1.7U\ml versus 0.1U\ml p<0.001). Vaginal expression of IL-6 was higher in PPROM cases compared to controls (respectively, median 31.19pg\ml versus 6.67pg\ml; p<0.001). Higher serum and vaginal sHLA-G were associated with both a shorter length of pregnancy and histological chorioamnionitis in the PPROM group. CONCLUSIONS: Higher vaginal and serum sHLA-G in PPROM cases may be a sign of local and systemic inflammation.

Cytokines in the perinatal period - Part I.

Successful pregnancy requires a state of immune homeostasis. Maternal tolerance of the genetically distinct fetoplacental unit is in part mediated by maternal and fetal pro- and anti-inflammatory cytokines; these cytokines have also been implicated in different pregnancy-related pathologic states. This two-part series seeks to provide anesthesiologists with an overview on selected perinatal cytokines in an effort to identify opportunities for research and improvements in clinical care. In part one, we review basic and pregnancy-related elements of the immune system, with an emphasis on the role of cytokines. From this foundation, we offer a perspective of a unique phenomenon witnessed within obstetric anesthesia - maternal temperature elevation associated with labor epidural analgesia.

Cytokines in noninvasively obtained amniotic fluid as predictors of fetal inflammatory response syndrome.

BACKGROUND: In patients with preterm premature rupture of membranes, intrauterine inflammation and/or infection is frequently present, can lead to fetal inflammatory response syndrome, and is associated with adverse neonatal outcome. Clinical decision making requires balancing the potential benefits of pregnancy prolongation against the risk of intrauterine infection. Diagnostic tests in maternal serum are of moderate prediction value and amniocentesis is an invasive procedure. Therefore, markers obtained noninvasively would be helpful in patients with expectant management. OBJECTIVES: To determine the predictive values of amniotic fluid interleukin-6 and tumor necrosis factor-α in vaginal secretions for fetal inflammatory response syndrome and/or histologic funisitis and for adverse neonatal outcome in patients with preterm premature rupture of membranes. STUDY DESIGN: In this prospective multicenter case-control study, vaginal secretions were sampled daily with a noninvasive method from 99 women with preterm premature rupture of membranes and expectant management. Amniotic fluid interleukin-6 and tumor necrosis factor-α were measured by 2 different immunoassays (an automated chemiluminescent enzyme immunoassay and a lateral flow immunoassay). After delivery, patients were divided into a control or a fetal inflammatory response syndrome group according to neonatal interleukin-6 in cord plasma and/or the presence of funisitis. Univariate and multivariate regression analyses were performed and prediction models were developed by calculating receiver operating characteristic curves. RESULTS: Gestational age at delivery was lower and latency period was longer in the fetal inflammatory response syndrome group compared to the control group. The strongest risk factor for composite adverse neonatal outcome was fetal inflammatory response syndrome (odds ratio, 2.48; confidence interval, 1.40-4.38). The median concentrations of amniotic fluid interleukin-6 and tumor necrosis factor-α in vaginal secretions were significantly higher in the fetal inflammatory response group compared to the control group in both immunoassays (P < .001). The area under the curve of the clinical reference model (including common clinical parameters) was 0.66. Adding interleukin-6 and tumor necrosis factor-α into the model improved the area under the curve to 0.92 (in both assays, interleukin-6 IMMULITE and QuickLine); 0.87 (tumor necrosis factor-α IMMULITE) and 0.94 (tumor necrosis factor-α QuickLine), respectively. CONCLUSION: The strongest risk factor for worse neonatal outcome (composite neonatal outcome) was fetal inflammatory response syndrome. Amniotic fluid interleukin-6 and tumor necrosis factor-α seem to be good predictors for fetal inflammatory response syndrome and for histologic funisitis and may improve the clinical management of patients with preterm premature rupture of membranes. The noninvasive technique of sampling amniotic fluid from vaginal secretions facilitates daily measurements and bedside assessment of cytokines and is in this respect preferable to invasive amniocentesis.

[Comparison of immunochromatographic tests Actim(®) Prom and Amnioquick(®) Duo for the rapid detection of premature rupture of membranes]. / Comparaison des tests immunochromatographiques Actim(®) Prom et Amnioquick(®) Duo pour le dépistage rapide de la rupture prématurée des membranes.

Premature rupture of membranes (PRM) affects 5 to 15% of pregnancies, leading to prematurity and neonatal infection. PRM can be identified by through various amniotic fluid proteins in vaginal secretions. The aim of this study is to compare two immunochromatographic tests based on the detection of insulin-like growth factor binding protein (IGFBP-1) and alpha-foeto protein (AFP) for one of the two tests in cervico-vaginal secretions. Two tests, Actim(®) Prom and Amnioquick(®) Duo were performed on 80 pregnant women with suspected PRM. Amnioquick(®) Duo allows the simultaneous detection of IGFBP-1 and AFP with an automated incubation and reading. The number of positive results is similar (Khi-deux = 0.173, p = 0.6773) for IGFBP-1 between the two tests and there is a good agreement (K = 0.621), with a proportion of negative results of 86%. The number of positive results for AFP is more important in comparison to IGFBP-1. Results positive/positive (Actim(®) Prom/Amnioquick(®)) for IGFBP-1 seems to be related to the time when tests have been performed, that is to say in the last weeks of pregnancy. In conclusion, both tests have similar performance, but there is a risk of false positive results with AFP, this can be explained by the presence of non-visible blood in samples. An automated incubation and reading allows a good reproducibility. Moreover, the computer data storage improve the post-analytical quality.

Activation of AMPK in human fetal membranes alleviates infection-induced expression of pro-inflammatory and pro-labour mediators.

INTRODUCTION: In non-gestational tissues, the activation of adenosine monophosphate (AMP)-activated kinase (AMPK) is associated with potent anti-inflammatory actions. Infection and/or inflammation, by stimulating pro-inflammatory cytokines and matrix metalloproteinase (MMP)-9, play a central role in the rupture of fetal membranes. However, no studies have examined the role of AMPK in human labour. METHODS: Fetal membranes, from term and preterm, were obtained from non-labouring and labouring women, and after preterm pre-labour rupture of membranes (PPROM). AMPK activity was assessed by Western blotting of phosphorylated AMPK expression. To determine the effect of AMPK activators on pro-inflammatory cytokines, fetal membranes were pre-treated with AMPK activators then stimulated with bacterial products LPS and flagellin or viral dsDNA analogue poly(I:C). Primary amnion cells were used to determine the effect of AMPK activators on IL-1ß-stimulated MMP-9 expression. RESULTS: AMPK activity was decreased with term labour. There was no effect of preterm labour. AMPK activity was also decreased in preterm fetal membranes, in the absence of labour, with PROM compared to intact membranes. AMPK activators AICAR, phenformin and A769662 significantly decreased IL-6 and IL-8 stimulated by LPS, flagellin and poly(I:C). Primary amnion cells treated with AMPK activators significantly decreased IL-1ß-induced MMP-9 expression. DISCUSSION: The decrease in AMPK activity in fetal membranes after spontaneous term labour and PPROM indicates an anti-inflammatory role for AMPK in human labour and delivery. The use of AMPK activators as possible therapeutics for threatened preterm labour would be an exciting future avenue of research.

The use of imaging technology in the assessment of the fetal inflammatory response syndrome-imaging of the fetal thymus.

The fetal inflammatory response syndrome (FIRS) describes a state of extensive fetal multi organ involvement during chorioamnionitis, and is associated with grave implications on perinatal outcome. The syndrome has been linked to the preterm parturition syndrome and is associated with inflammation/infection processes in most of the fetal organs. The fetal thymus, a major organ in the developing immune system involutes during severe neonatal disease and has been shown to be smaller in fetuses with FIRS. Various methods for imaging of the fetal thymus and measurement are described. Currently the only method to diagnose FIRS prenatally is through amniocentesis. We suggest that women who are admitted with preterm labor with intact membranes and those with PPROM should have a detailed sonographic examination of the fetal thymus as a surrogate marker of fetal involvement in intrauterine infection/inflammation processes.