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PubMed2001

Uncoupling of inflammatory and destructive mechanisms in arthritis.

OBJECTIVE: To update clinicians on recent advances in the differentiation of the mechanisms of inflammation and cartilage destruction in the pathogenesis of rheumatoid arthritis (RA). METHODS: We present analysis of recent published literature and abstracts that elucidates the independent actions of pivotal proinflammatory cytokines. These experimental data provide the framework for understanding the uncoupling of destructive and inflammatory mechanisms in arthritis. RESULTS: Tumor necrosis factor-alpha (TNF-alpha) is an important mediator in the inflammation that occurs in RA. Interleukin-1 (IL-1) has a dominant effect on cartilage destruction that occurs later in the disease process. TNF-independent IL-1 production occurs in many RA model situations. Cytokine balance determines the erosive nature of the disease. CONCLUSION: IL-1 is at least as important as TNF-alpha in promoting the disease process. The pathways by which the inflammatory and destructive changes occur suggest that targeted anticytokine intervention will arrest the cartilage damage that occurs in patients with RA.

Animals↗

PubMed1998

beta-Amyloid fibrils activate parallel mitogen-activated protein kinase pathways in microglia and THP1 monocytes.

The senile plaques of Alzheimer's disease are foci of local inflammatory responses, as evidenced by the presence of acute phase proteins and oxidative damage. Fibrillar forms of beta-amyloid (Abeta), which are the primary constituents of senile plaques, have been shown to activate tyrosine kinase-dependent signal transduction cascades, resulting in inflammatory responses in microglia. However, the downstream signaling pathways mediating Abeta-induced inflammatory events are not well characterized. We report that exposure of primary rat microglia and human THP1 monocytes to fibrillar Abeta results in the tyrosine kinase-dependent activation of two parallel signal transduction cascades involving members of the mitogen-activated protein kinase (MAPK) superfamily. Abeta stimulated the rapid, transient activation of extracellular signal-regulated kinase 1 (ERK1) and ERK2 in microglia and ERK2 in THP1 monocytes. A second superfamily member, p38 MAPK, was also activated with similar kinetics. Scavenger receptor and receptor for advanced glycated end products (RAGE) ligands failed to activate ERK and p38 MAPK in the absence of significant increases in protein tyrosine phosphorylation, demonstrating that scavenger receptors and RAGE are not linked to these pathways. Importantly, the stress-activated protein kinases (SAPKs) were not significantly activated in response to Abeta. Downstream effectors of the MAPK signal transduction cascades include MAPKAP kinases, such as RSK1 and RSK2, as well as transcription factors. Exposure of microglia and THP1 monocytes to Abeta resulted in the activation of RSK1 and RSK2 and phosphorylation of cAMP response element-binding protein at Ser133, providing a mechanism for Abeta-induced changes in gene expression.

Amyloid beta-Peptides↗

PubMed2026

The proteomic profile of leisure time physical activity across two decades: implications for future cardiovascular risk and mortality.

AIMS: We aimed to (i) investigate associations between leisure time physical activity level cumulated over 20 years and multiple plasma proteins and (ii) explore if proteins significantly associated with physical activity are also associated with risk of imminent myocardial infarction (MI), long-term MI, and mortality. METHODS AND RESULTS: In the cohort Uppsala Longitudinal Study of Adult Men, leisure time physical activity was self-reported at Ages 50, 60, and 70. At Age 70, 720 plasma proteins were analysed in 782 participants with up to 19.3 years of follow-up for MI and 26.3 years follow-up for mortality. In the nested case-cohort study Markers of Imminent Myocardial Infarction, plasma proteins were measured in disease-free individuals from six European cohorts. Cases (n = 420) were those with acute MI within 6 months of a blood draw, with up to four cohort representatives per case (n = 1598). A higher level of leisure time physical activity level was inversely associated with 12 plasma proteins after adjusting for age, education, smoking, and established cardiovascular risk factors (Bonferroni-corrected P < 0.000069). Of these 12 proteins, interleukin-6 was associated with increased incidence of imminent MI [hazard ratio, HR 1.22; 95% confidence interval, CI (1.09-1.37)], tumour necrosis factor receptor superfamily member 11A was associated with increased long-term MI incidence [HR 1.22 (1.01-1.48)] and 11 proteins were associated with increased mortality [HR 1.14-1.30 (1.01-1.42)]. CONCLUSION: These findings confirm and extend our understanding of how physical activity could assert its beneficial effect on cardiovascular health through proteins involved with modulating inflammatory, immune, and metabolic pathways. Further research is needed to explore the causal mechanisms behind these associations. LAY SUMMARY: In this study, we aimed to investigate (i) whether leisure time physical activity level cumulated over 20 years is associated with 720 plasma proteins and (ii) if proteins that are significantly associated with leisure time physical activity level across 20 years in Part 1 are also associated with imminent and long-term risk of myocardial infarction (MI) and mortality.Higher physical activity level over 20 years was inversely associated with 12 plasma proteins involved in inflammatory, immune, and metabolic processes. Several plasma proteins were in turn associated with MI and mortality.Findings confirm and extend our understanding how physical activity could assert its beneficial effect on cardiovascular health via the circulating plasma proteins.

Humans↗

PubMed1991

Activation-independent binding of human memory T cells to adhesion molecule ELAM-1.

The induction of an ensemble of adhesion molecules on endothelial cells by inflammatory cytokines is likely to be crucial to the differential migration of T-lymphocyte subsets into inflammatory sites. Two molecular pathways involving the VLA-4 and LFA-1 integrins are known to mediate T-cell adhesion to activated endothelium. Here we show that a third pathway involving the rapidly inducible endothelial cell-surface adhesion molecule ELAM-1 contributes to the binding of resting CD4+ T cells to IL-1-induced human endothelial cells. All three pathways contribute to the greater adhesion to endothelium of memory T cells than naive T cells. There are two unique features of T-cell adhesion to purified ELAM-1: first, ELAM-1 exclusively mediates adhesion of memory T cells; second, memory T-cell binding to ELAM-1 is independent of acute activation events that regulate integrin-mediated adhesion. Thus, ELAM-1 may be of primary importance in the initial attachment of memory T cells to inflamed endothelium in vivo and to the preferential migration of memory T cells into tissue and inflammatory sites.

CD4 Antigens↗

PubMed2003

Review article: mitogen-activated protein kinases in chronic intestinal inflammation - targeting ancient pathways to treat modern diseases.

Conventional treatment of chronic inflammatory disorders, including inflammatory bowel diseases, employs broad-range anti-inflammatory drugs. In order to reduce the side-effects and increase the efficacy of treatment, several strategies have been developed in the last decade to interfere with intercellular and intracellular inflammatory signalling processes. The highly conserved mitogen-activated protein kinase pathways regulate most cellular processes, particularly defence mechanisms such as stress reactions and inflammation. In this review, we provide an overview of the current knowledge of the specificity and interconnection of mitogen-activated protein kinase pathways, their functions in the gut immune system and published and ongoing studies on the role of mitogen-activated protein kinases in inflammatory bowel disease. The development of mitogen-activated protein kinase inhibitors and their use for the therapy of inflammatory disorders is a paradigm of the successful bridging of the gap between basic research and clinical practice.

Acute Disease↗

PubMed2007

Pancreatitis-associated protein: from a lectin to an anti-inflammatory cytokine.

Pancreatitis-associated protein (PAP) was discovered in the pancreatic juice of rats with acute pancreatitis. PAP is a 16 kDa secretory protein structurally related to the C-type lectins although classical lectin-related function has not been reported yet. Then, it was demonstrated that PAP expression may be activated in some tissues in a constitutive or injury- and inflammation-induced manner. More recently, it has been found that PAP acts as an anti-inflammatory factor in vitro and in vivo. PAP expression can be induced by several pro- and anti-inflammatory cytokines and by itself through a JAK/STAT3-dependent pathway. PAP is able to activate the expression of the anti-inflammatory factor SOCS3 through the JAK/STAT3-dependent pathway. The JAK/STAT3/SOCS3 pathway seems to be a common point between PAP and several cytokines. Therefore, it is reasonable to propose that PAP is a new anti-inflammatory cytokine.

Animals↗

PubMed2006

Innate immune response to Francisella tularensis is mediated by TLR2 and caspase-1 activation.

Francisella tularensis, a gram-negative, facultative, intracellular bacterium, is the etiologic agent of tularemia and a category A bioterrorism agent. Little is known about the mechanism of pathogenesis of tularemia. In this paper, we describe the interaction of the live vaccine strain of F. tularensis with the innate immune system. We have found that in human and mouse dendritic cells, F. tularensis elicited a powerful inflammatory response, characterized by production of a number of cytokines and chemokines. Using cells derived from TLR2-deficient mice and in vitro transfection assays, we demonstrated that this response was mediated by TLR2 and did not require the LPS-binding protein. F. tularensis appeared to activate TLR2/TLR1 and TLR2/TLR6 heterodimers. IL-1beta secretion, a reflection of caspase-1 activation, was induced by live but not heat-killed F. tularensis, despite the fact that both forms of the bacterium equally induced the IL-1beta transcript. Our results identified activation of TLR2 and caspase-1 as the two main cellular pathways responsible for the inflammatory response to F. tularensis.

Animals↗

PubMed2005

Intracellular signaling mechanisms underlying the expression of pro-inflammatory mediators in airway diseases.

UNLABELLED: Several factors have been shown to trigger the pathogenesis of asthma and airway inflammation mechanisms. Elevated levels of pro-inflammatory cytokines including tumor necrosis factor-alpha and interleukin-1beta in the bronchoalveolar lavage fluid have been detected in asthmatic patients. Cytokines exert as potent stimuli in inflammatory responses through up-regulation of many gene expressions, including cytokines, chemokines, cytosolic phospholipase A2, cyclooxygenase, adhesion molecules and matrix metalloproteinases. The extent of these gene expressions is correlated with the severity of inflammation. However, the intracellular signaling mechanisms underlying the expression of target proteins regulated by these factors are elusive. The mechanisms underlying actions by cytokines may be integrated to the signaling networks that augment airway inflammation by recruiting leukocytes and leading to airway remodeling. Although cytokines have been reported to activate mitogen-activated protein kinases including p42/p44 and p38, and c-Jun N-terminal kinase, the relationship between the activation of these pathways and expression of inflammatory genes remains unknown. Moreover, many genes regulated by mitogen-activated protein kinases are dependent on NF-kappaB for transcription. NF-kappaB has also been shown to be involved in target protein expression at the transcriptional level in various cell types. We review the mechanisms underlying the intracellular signaling involved in several target protein expressions induced by cytokines in airway resident cells. CONCLUSION: Increased understanding of signal transduction mechanisms underlying target protein gene expression will create opportunities for the development of anti-inflammation therapeutic strategies.

Asthma↗

PubMed1987

Inhibition of carrageenin-induced pedal oedema in rats by immobilisation stress.

The effect of immobilisation stress on acute pedal inflammation induced by carrageenin, and the mechanism of stress-induced anti-inflammatory effect, were investigated in male Wistar strain albino rats. Carrageenin-induced pedal inflammation oedema was attenuated by immobilisation stress in a time-dependent manner, when the rats were restrained for 30 min, 1 h, and 2 h immediately after the induction of the inflammation. Pentobarbitone exhibited significant anti-inflammatory effect of its own in an anaesthetic dose and also inhibited stress (1 h)-induced attenuation of the inflammation. Likewise, lignocaine, injected behind the knee joint of the inflamed limb, attenuated the inflammation and also inhibited the stress-induced anti-inflammatory effect. These findings indicate the importance of the central nervous system (CNS) and the afferent/efferent neural pathways from and to the inflammatory site, in inflammation and in stress-induced anti-inflammatory effect. Earlier studies from this laboratory have shown that the central noradrenergic, histaminergic, serotonergic and GABA-ergic neurotransmitter systems have a modulatory anti-inflammatory effect on carrageenin-induced pedal oedema. Since all these neurotransmitter systems have been reported to be activated by stress, their role was assessed in the inflammation-attenuation effect of immobilisation stress. The present studies indicate that, of these neurotransmitters, only the central noradrenergic system is involved in the anti-oedema effect of stress. Endogenous opioid peptides may also be involved in the stress-inflammation interaction, since naloxone inhibited the stress effect. Bilateral adrenalectomy and peripheral chemical sympathectomy, induced by i.p. administration of 6-hydroxydopamine, augmented carrageenin oedema and antagonised the stress-induced anti-inflammatory effect. However, metyrapone, an inhibitor of endogenous corticoid synthesis, failed to inhibit the stress effect. These findings indicate that the sympatho-medullary system, which is known to be activated during stress, is responsible for the observed anti-inflammatory effect of immobilisation stress, rather than augmented release of adrenal corticoids. It is suggested that the observed inflammation reducing effect of immobilisation stress is a consequence of increased central noradrenergic and peripheral sympatho-medullary activity.

5,6-Dihydroxytryptamine↗

PubMed2006

Sequential gene expression profiling in lung transplant recipients with chronic rejection.

STUDY OBJECTIVES: Chronic allograft rejection is the leading cause of morbidity and mortality for long-term survivors of lung transplantation. Previous studies have implicated only isolated genes in the development of chronic rejection and have not examined multiple pathways in an individual concurrently. Using microarray technology, we identified and compared gene expression profiling in lung transplant recipients with and without chronic rejection, and follow sequential expression of genes differentially expressed between the two groups. DESIGN: Prospective, cohort study. SETTING: Single lung transplant center. PATIENTS OR PARTICIPANTS: Eleven transplant recipients with chronic rejection were matched with 9 control transplant recipients. INTERVENTIONS: All recipients underwent surveillance bronchoscopies at predetermined times to rule out infection and/or acute rejection. Gene expression profiling was obtained from hybridizing BAL fluid cell RNA to a 96-gene microarray. MEASUREMENTS AND RESULTS: Fifteen genes were found to be significantly differentially expressed between the two patient groups, and they are involved in inflammatory, fibrotic, and apoptotic pathways. Temporal expression of the significant genes demonstrated a change in their levels at the onset of chronic rejection, with normalization to prerejection levels as rejection continued. CONCLUSIONS: We conclude that microarray technology is valuable in studying the mechanism of chronic lung rejection, and the expression of genes in multiple pathways is elevated in patients with chronic lung rejection.

Adult↗

PubMed2003

Anti-inflammatory properties of lipid oxidation products.

Oxidative modification of lipids occurs during inflammatory processes and leads to the formation and accumulation of biologically active lipid oxidation products that induce specific cellular reactions. These reactions lead to a modulation of the inflammatory process and may determine the fate and outcome of the body's reaction in acute inflammation during host defense. The processes by which oxidized lipids may play an important role include resolution of inflammation involving apoptosis, chronic inflammatory processes, and innate and adaptive immune responses. The classical view of lipid oxidation products is that they can induce and propagate chronic inflammatory reactions. However, evidence is accumulating that cells and tissues respond towards these oxidatively formed stress signals also by activation of anti-inflammatory processes. These include defense strategies such as (a) induction of signaling pathways leading to the upregulation of anti-inflammatory genes, (b) inhibition of signaling pathways coupled to the expression of proinflammatory genes, and (c) preventing the interaction of proinflammatory bacterial products with host cells. This contribution summarizes recent findings on the anti-inflammatory action of oxidized lipoproteins and lipid oxidation products. We discuss confirmed and suggested mechanisms as well as the (patho)physiological significance of these findings.

Animals↗

PubMed2003

Down-regulation of proinflammatory capacity during apoptosis in human polymorphonuclear leukocytes.

Polymorphonuclear leukocytes (PMNs) are essential to innate immunity in humans and contribute significantly to inflammation. Although progress has been made, the molecular basis for termination of inflammation in humans is incompletely characterized. We used human oligonucleotide microarrays to identify genes encoding inflammatory mediators that were differentially regulated during the induction of apoptosis. One hundred thirty-three of 212 differentially expressed genes encoding proinflammatory factors, signal transduction mediators, adhesion molecules, and other proteins that facilitate the inflammatory response were down-regulated during the induction of apoptosis following PMN phagocytosis. Among these, 42 genes encoded proteins critical to the inflammatory response, including receptors for IL-8 beta, IL-10 alpha, IL-13 alpha 1, IL-15 alpha, IL-17, IL-18, C1q, low-density lipoprotein, IgG Fc (CD32), and formyl peptide, Toll-like receptor 6, platelet/endothelial cell adhesion molecule-1 (CD31), P-selectin (CD62), IL-1 alpha, IL-16, and granulocyte chemoattractant protein-2 were down-regulated. Many of these genes were similarly down-regulated during Fas-mediated or camptothecin-induced apoptosis. We used flow cytometry to confirm that IL-8R beta (CXCR2) and IL-1 alpha were significantly down-regulated during PMN apoptosis. We also discovered that 23 genes encoding phosphoinositide and calcium-mediated signal transduction components, which comprise complex pathways essential to the inflammatory response of host cells, were differentially regulated during PMN apoptosis. Importantly, our data demonstrate that PMNs down-regulate proinflammatory capacity at the level of gene expression during induction of apoptosis. These findings provide new insight into the molecular events that resolve inflammation following PMN activation in humans.

Apoptosis↗

PubMed2003

Correlation of very long chain fatty acid accumulation and inflammatory disease progression in childhood X-ALD: implications for potential therapies.

This study was designed to understand the role of inflammatory mediators involved in the neurobiology of childhood adrenoleukodystrophy (cALD) by comparing the differential expression of the inflammatory mediators with metabolite very long chain fatty acids that accumulate in this disease. Histopathological examinations indicated extensive demyelination and accumulation of infiltrates in perivascular cuffs in plaque area (PA) and inflammatory area (IA) compared to normal looking area (NLA) of the cALD brain and controls. The PA had excessive accumulation of cholesterol ester (25-30-fold), VLC fatty acids (8-12-fold), and exhaustive depletion of cholesterol (60-70%) and sphingomyelin (50-55%) in comparison to controls. The mRNA expression of cytokines (IL-1alpha, IL-2, IL-3, IL-6, TNF-alpha, and GM-CSF), chemokines (CCL2, -4, -7, -11, -16, -21, -22, CXCL1, CX3CL1, and SDF-2) and iNOS in IA was significantly increased compared to NLA of the cALD and controls determined by gene array, semiquantitative RT-PCR, and immunohistochemistry. These results indicate that accumulation of VLC fatty acid contents in membrane domains associated with signal transduction pathways may trigger the inflammatory process through activation of resident glial cells (microglia and astrocytes) resulting in loss of myelin and oligodendrocytes.

Adrenoleukodystrophy↗

PubMed2000

Interleukin-1 signaling in mouse astrocytes involves Akt: a study with interleukin-4 and IL-10.

Although astrocytes are well known to respond to the pro-inflammatory cytokine, interleukin-1 (IL-1), the receptor and post-receptor mechanisms that mediate IL-1 effects in this cell type are complex and need further investigation. Using electrophoretic mobility shift assay (EMSA), we show that IL-1beta-induced NFkappaB activation in primary culture of mouse astrocytes is mediated by the interaction of this cytokine with the IL-1 type I receptor/IL-1 receptor accessory protein complex, as demonstrated by the ability of blocking monoclonal antibodies against these receptors to attenuate NFkappaB activation. In addition to NFkappaB activation, IL-1beta is also able to phosphorylate Akt, as demonstrated by Western blot. The observation that addition of wortmanin, that specifically blocks Akt phosphorylation, also attenuates NFkappaB activation can be interpreted that Akt phosphorylation interacts with IL-1 signaling pathways. Furthermore, anti-inflammatory cytokines such as IL-4 and IL-10 that block IL-1b-induced NFkappaB activation also attenuate IL-1beta-induced Akt phosphorylation, despite the fact that IL-4 and IL-10 in isolation induced Akt phosphorylation. All these findings point to an interaction between Akt and NFkappaB-dependent IL-1 signaling in the primary culture of astrocytes.

Animals↗

PubMed2001

Increased retinoid signaling in vascular smooth muscle cells by proinflammatory cytokines.

Retinoids have been shown to modulate inflammation and the immune response in many cell types including macrophages, endothelial cells, and vascular smooth muscle cells. However, present knowledge of whether inflammatory mediators modulate vitamin A status in these cells is limited. To identify the role of inflammation on retinoid metabolism in vascular smooth muscle cells, the cells were exposed to a combination of proinflammatory cytokines: interleukin-1beta, interferon-gamma, and lipopolysaccharides. Without stimulation with proinflammatory cytokines, vascular smooth muscle cells expressed retinol dehydrogenases-2 and 5 mRNA detected by RT-PCR. Stimulation with the combination of cytokines induced a substantial increase of retinol dehydrogenase-5 mRNA. This was associated with increased production of ligands for retinoic acid receptors, when assayed in a retinoic acid receptor-dependent luciferase reporter system. Our results demonstrate that inflammatory mediators activate the retinoid metabolic pathway in vascular smooth muscle cells, which potentially may modulate the inflammatory response in the vascular wall.

Alcohol Oxidoreductases↗

PubMed2006

Inhibitory effects of eicosapentaenoic acid on lipopolysaccharide-induced activation in BV2 microglia.

Upon activation, microglia release proinflammatory mediators that play important roles in eliciting neuroinflammatory responses associated with neurodegenerative diseases. The anti-inflammatory properties of eicosapentaenoic acid (EPA) have been known, however, the effects responsible for lipopolysaccharide (LPS)-induced activation remain poorly understood in microglia. In the present study, we investigated the effects of EPA on the expression of proinflammatory mediators in LPS-stimulated BV2 microglia. EPA significantly inhibited the release of nitric oxide (NO), prostaglandin E(2) (PGE(2)) and proinflammatory cytokines such as interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF)-alpha in a dose-dependent manner. EPA also attenuated the production of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and proinflammatory cytokines at mRNA and/or protein levels. Moreover, EPA suppressed NF-kappaB activation by blocking IkappaB degradation, and also blocked the mitogen-activated protein kinases (MAPKs) such as ERK, p38 and JNK, and the Akt pathway. The anti-inflammatory properties of EPA may be useful for ameliorating neurodegenerative diseases as well as suppressing LPS-induced shock.

Animals↗

PubMed2002

Role of cytokines and oxidative stress in the pathophysiology of acute pancreatitis: therapeutical implications.

Severe acute pancreatitis causes a high incidence of mortality due to the systemic inflammatory response syndrome leading to multiple organ failure. At present, there is no treatment against severe acute pancreatitis, other than supportive critical care. The relationship between pancreatic injury and the uncontrolled systemic response is not completely understood. Nevertheless, experimental and clinical evidences have shown that pro-inflammatory cytokines and oxidative stress are critically involved in the development of local and systemic complications associated with severe acute pancreatitis. Serum levels of pro-inflammatory cytokines, such as TNF-alpha and IL-1beta, increase during the course of acute pancreatitis and they appear to be the driving force for the initiation and propagation of the systemic response. Accordingly, pretreatment with an antibody against TNF-alpha or blockade of TNF-alpha production with pentoxifylline ameliorates experimental acute pancreatitis. In addition, serum IL-6 and IL-8 levels appear to be correlated with severity of pancreatic inflammation. The role of oxidative stress in acute pancreatitis has been evidenced indirectly by beneficial effects of antioxidants as well as directly by pancreatic glutathione depletion and increased lipid peroxidation. Furthermore, circulating xanthine oxidase released by the damaged pancreas acts as a source of systemic oxidative stress contributing to lung inflammation. In conclusion, pancreatic injury seems to trigger at least two different pathways, i.e. pro-inflammatory cytokines and oxidative stress, both involved in the systemic effects of acute pancreatitis. Elucidation of these mechanisms and their interactions is critical to develop a treatment based on the pathophysiology of acute pancreatitis.

Acute Disease↗

PubMed1992

[Immunological phenomena in pulpal-periapical lesions].

Based on an extensive review of the literature, the authors examine immunological reactions in pulpal and periapical lesions. Although it has been known for some time that bacterial infection causes this pathology, attention has been recently focused on immunological factors in the ambit of the phlogistic process. The present study examines the correlation between the latter and the type of extent of antigenic response, focusing attention on their important role in the phenomena of osteoclastic activation and inhibition of bone repair. From a physiological point of view there are few inflammatory cells in dental pulp, like macrophages and T lymphocytes. When the pulp comes into contact with the antigenic substance it activates a specific and aspecific immune response: the form through the activation of B and T lymphocytes, and the latter through the action of LPS, PMN and complement. An important role in the immune response is played by the cytokines which are able to regulate the intensity and duration of the immune response against potential pathogenic agents. It was initially thought that these were only produced by lymphocytes and as a result they were known as lymphokines. Later it was observed that other cell populations were also able to produce them. Phlogosis of the periapex starts before the pulp is fully necrotic. Tissue detritus and products of bacterial derivation escape through the numerous endoparadontal communication pathways and stimulate an inflammatory response by the vascular system of the parodontal ligament. The concomitant immune reaction occurs due to the tendency to block and restrict the inflammation to the radicular channels, thus preventing its diffusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibody Formation↗