This study was designed to evaluate the response of innate immunity to acute bacterial inflammation in terms of cytokines and other biomolecules concentration changes in the blood of investigated childhood oncology patients during the beginning of febrile neutropenia (FN) episode and to assess the relevance of these biomarkers for sepsis/bacteremia evaluation. This study was performed at Vilnius University Children Hospital and State Research Institute Centre for Innovative Medicine from 2009 to 2011. Serum samples were collected during 82 fever episodes in a total of 53 oncology patients. The study population consisted of pediatric oncology patients admitted to the hospital with the diagnosis of neutropenia and fever. According to microbiological and clinical findings, patients with episodes of FN were classified into 2 groups: 1) fever of unknown origin (FUO) group – patients with negative blood culture, absence of clinical signs of sepsis and clinically or microbiologically documented local infection, 2) septic/bacteremia (SB) group – patients with positive blood culture (documented Gram-positive or Gram-negative bacteremia) and/or clinically documented sepsis. We measured the levels of cytokines (IL-6, IL-8, IL-10), their receptors (sIL-2R) and other biomarkers (PCT, CRP, sHLA-G) for three consecutive days. We showed that on day 1 the most accurate biomarkers for bacteremia/sepsis discrimination were cytokines (IL-6, IL-10, IL-8), on day 2 – IL-8 and PCT. On day 1 the... [to full text] / Viena iš pagrindinių taikomos šiuolaikinės intensyvios chemoterapijos komplikacijų yra organizmo imuninės sistemos slopinimas ir su tuo susijusi neutropenija, kuri savo ruožtu sąlygoja padidėjusią riziką susirgti bakterinės kilmės infekcinėmis ligomis. Šio darbo tikslas buvo įvertinti ūmaus bakterinio uždegimo bei sepsio patogenezėje dalyvaujančių citokinų (IL-6, IL-8, IL-10), citokinų receptorių (sIL-2R), ūmios fazės baltymų bei kitų imuninio atsako komponentų (CRB, PCT, sHLA-G) tinkamumą bakterinio proceso ankstyvai diagnostikai tarp pacientų su febrline neutropenija (FN), šių biožymenų tinkamumą ir pritaikomumą kasdienėje klinikinėje praktikoje. Tiriamoji medžiaga surinkta 2009–2011 m. Vilniaus universiteto Vaikų ligoninės Onkohematologijos skyriuje. Į tyrimą buvo įtraukta 53 onkohematologinėmis ligomis sergantys vaikai su FN, kurie gydymo eigoje turėjo 82 karščiavimo epizodus. Nuo pirmos karščiavimo dienos tris dienas iš eilės buvo imami kraujo mėginiai bei nustatomos citokinų (IL-6, IL-8, IL-10), CRB, PCT, sHLA-G ir sIL-2R koncentracijos. Remiantis klinikinių bei mikrobiologinių tyrimų duomenimis, FN epizodai buvo suskirstyti į dvi grupes – neaiškios kilmės karščiavimo (NKK), į kurią buvo įtraukti pacientai be sepsio požymių bei su neigiamais mikrobiologiniais pasėliais ir bakteriemijos/sepsio (BS). BS grupę sudarė pacientai su teigiamais mikrobiologiniais pasėliais ir(ar) kliniškai diagnozuotu sepsiu. Mūsų atlikto tyrimo rezultatais bakteriemijos/sepsio vertinimui FN... [toliau žr. visą tekstą]

Viena iš pagrindinių taikomos šiuolaikinės intensyvios chemoterapijos komplikacijų yra organizmo imuninės sistemos slopinimas ir su tuo susijusi neutropenija, kuri savo ruožtu sąlygoja padidėjusią riziką susirgti bakterinės kilmės infekcinėmis ligomis. Šio darbo tikslas buvo įvertinti ūmaus bakterinio uždegimo bei sepsio patogenezėje dalyvaujančių citokinų (IL-6, IL-8, IL-10), citokinų receptorių (sIL-2R), ūmios fazės baltymų bei kitų imuninio atsako komponentų (CRB, PCT, sHLA-G) tinkamumą bakterinio proceso ankstyvai diagnostikai tarp pacientų su febrline neutropenija (FN), šių biožymenų tinkamumą ir pritaikomumą kasdienėje klinikinėje praktikoje. Tiriamoji medžiaga surinkta 2009–2011 m. Vilniaus universiteto Vaikų ligoninės Onkohematologijos skyriuje. Į tyrimą buvo įtraukta 53 onkohematologinėmis ligomis sergantys vaikai su FN, kurie gydymo eigoje turėjo 82 karščiavimo epizodus. Nuo pirmos karščiavimo dienos tris dienas iš eilės buvo imami kraujo mėginiai bei nustatomos citokinų (IL-6, IL-8, IL-10), CRB, PCT, sHLA-G ir sIL-2R koncentracijos. Remiantis klinikinių bei mikrobiologinių tyrimų duomenimis, FN epizodai buvo suskirstyti į dvi grupes – neaiškios kilmės karščiavimo (NKK), į kurią buvo įtraukti pacientai be sepsio požymių bei su neigiamais mikrobiologiniais pasėliais ir bakteriemijos/sepsio (BS). BS grupę sudarė pacientai su teigiamais mikrobiologiniais pasėliais ir(ar) kliniškai diagnozuotu sepsiu. Mūsų atlikto tyrimo rezultatais bakteriemijos/sepsio vertinimui FN... [toliau žr. visą tekstą] / This study was designed to evaluate the response of innate immunity to acute bacterial inflammation in terms of cytokines and other biomolecules concentration changes in the blood of investigated childhood oncology patients during the beginning of febrile neutropenia (FN) episode and to assess the relevance of these biomarkers for sepsis/bacteremia evaluation. This study was performed at Vilnius University Children Hospital and State Research Institute Centre for Innovative Medicine from 2009 to 2011. Serum samples were collected during 82 fever episodes in a total of 53 oncology patients. The study population consisted of pediatric oncology patients admitted to the hospital with the diagnosis of neutropenia and fever. According to microbiological and clinical findings, patients with episodes of FN were classified into 2 groups: 1) fever of unknown origin (FUO) group – patients with negative blood culture, absence of clinical signs of sepsis and clinically or microbiologically documented local infection, 2) septic/bacteremia (SB) group – patients with positive blood culture (documented Gram-positive or Gram-negative bacteremia) and/or clinically documented sepsis. We measured the levels of cytokines (IL-6, IL-8, IL-10), their receptors (sIL-2R) and other biomarkers (PCT, CRP, sHLA-G) for three consecutive days. We showed that on day 1 the most accurate biomarkers for bacteremia/sepsis discrimination were cytokines (IL-6, IL-10, IL-8), on day 2 – IL-8 and PCT. On day 1 the... [to full text]

Intravenous immunoglobulin (IVIg) has been used to treat a variety of autoimmune disorders including multiple sclerosis (MS); however, its mechanism of action remains elusive. Our results demonstrate a novel finding wherein IVIg treatment induces a dramatic surge (>1000-fold increase) in the levels of IL-11 in the circulation and that the liver is the organ of increased IL-11 transcription. Furthermore, we show that IL-11Rα knockout mice, although initially protected, become resistant to protection by IVIg during experimental autoimmune encephalomyelitis (EAE) and develop disease with a similar incidence and severity as control-treated IL-11Rα-/- mice. The inability of IVIg to prevent EAE in IL-11Rα-/- mice correlated with a failure of this agent to decrease IL-17 production by myelin-reactive T-cells in the draining lymph nodes. Finally, we show that IL-11 can directly inhibit IL-17 production by lymph node cells in culture. Together, these results implicate IL-11 as an important immune effector of IVIg in the amelioration of EAE.

Intravenous immunoglobulin (IVIg) has been used to treat a variety of autoimmune disorders including multiple sclerosis (MS); however, its mechanism of action remains elusive. Our results demonstrate a novel finding wherein IVIg treatment induces a dramatic surge (>1000-fold increase) in the levels of IL-11 in the circulation and that the liver is the organ of increased IL-11 transcription. Furthermore, we show that IL-11Rα knockout mice, although initially protected, become resistant to protection by IVIg during experimental autoimmune encephalomyelitis (EAE) and develop disease with a similar incidence and severity as control-treated IL-11Rα-/- mice. The inability of IVIg to prevent EAE in IL-11Rα-/- mice correlated with a failure of this agent to decrease IL-17 production by myelin-reactive T-cells in the draining lymph nodes. Finally, we show that IL-11 can directly inhibit IL-17 production by lymph node cells in culture. Together, these results implicate IL-11 as an important immune effector of IVIg in the amelioration of EAE.

Equine influenza virus causes a mild, self-limiting upper respiratory disease in its natural host. In stark contrast, equine influenza viruses of the H7N7 subtype produce lethal infection in BALB/c mice. This dissertation explored the mechanism underlying the differential pathogenicity of the equine H7N7 influenza virus observed in horses and BALB/c mice. Initially, a comparative study of the pathogenesis was conducted in BALB/c mice inoculated intranasally with a representative isolate of either H7N7 or H3N8 subtype equine influenza virus. All H3N8 virus-infected mice survived the infection whereas 100% mortality was documented for the mice receiving the H7N7 virus by day 8 post infection. Both viruses replicated to a similar degree in the lungs at the early stages of infection. However, after day 2 post infection until the death of the mice, the pulmonary viral loads of the H7N7 group were significantly higher than those of the control, whereas the H3N8 virus was eventually eradicated from the mice at day 7 p.i. Correspondingly, a vigorous pro-inflammatory cytokine response in the lung was induced by the H7N7 virus but not the H3N8 virus, which reflected a desperate attempt by the host immune responses to restrain the overwhelming infection. The H7N7 virus was poorly sensitive to the innate immune containment, resulting in a significant higher cumulative mortality rate than that of the control virus in chicken embryos aged 9 days and older. On the contrary, in horses, replication of the paired viruses was completely cleared by the host immune responses at day 7 p.i. and the infections produced an acute yet non-lethal illness, albeit the H3N8 virus induced generally more pronounced clinical manifestations than the H7N7 virus. The clinical severity correlated to the difference in cytokine-inducing capacity between the two viruses in horses, as evidenced by the finding that the H3N8 virus triggered significantly higher levels of gene transcription of multiple key inflammatory cytokines in the circulation than those seen for the H7N7 virus. In addition, equine peripheral monocyte-derived macrophages were found to be a target of equine influenza virus and can support the productive replication of the virus in vitro.

Le neutrophile humain est une composante essentielle du système immunitaire inné. Il joue un rôle-clé comme phagocyte professionnel pour la défense contre les agents externes. De plus, il a la capacité de libérer un large éventail de produits antimicrobiens et de produire également diverses protéines immunorégulatrices, dont une vaste gamme de cytokines (IL-8, MIP-1[alpha]/[beta], IP-10, I-TAC, TNF-[alpha], etc.). La génération de ces dernières permet le recrutement massif de neutrophiles et d'autres populations leucocytaires au site inflammatoire, contribuant ainsi au bon déroulement de la réponse inflammatoire. La génération de cytokines par le neutrophile humain est induite par différents agonistes, dont des molécules bactériennes (LPS, peptides N-formylés) ou les médiateurs inflammatoires (cytokines, chimiokines, facteurs de croissance). Ces molécules vont activer des récepteurs à la surface du neutrophile et déclancher ainsi plusieurs voies de signalisation et des facteurs transcriptionnels. Dans la présente étude, nous avons déterminé l'impact de la voie de signalisation MEK/ERK dans l'induction de l'expression des cytokines chez le neutrophile humain isolé du sang périphérique. Nous avons noté un découplage du module MEK/ERK suite à une stimulation avec certains agonistes pro-inflammatoires (LPS, TNF-[alpha]), mais par pour d'autres (fMLP, GM-CSF). L'utilisation de différentes classes d'agonistes et d'inhibiteurs pharmacologiques des voies de signalisation nous a permis de mettre en évidence les rôles différents de MEK et de ERK en ce qui concerne la sécrétion et la transcription de cytokines. Les kinases ERK et MEK sont toutes deux impliquées dans la sécrétion de cytokines, mais ERK est la seule des deux qui est associée à la transcription. Par contre, nous n'avons toujours pas identifié la kinase responsable de l'activation de ERK lorsque le module MEK/ERK est découplé. Enfin, à défaut d'identifier la kinase qui phosphoryle ERK, nous montrons que la MAP3K, TAK1, agit en amont de ERK et de MEK chez les neutrophiles. Nos résultats suggèrent que les thérapies basées sur l'inhibition de MEK devront être complémentées d'une inhibition de ERK, en particulier dans des maladies inflammatoires chroniques à forte prédominance neutrophilique.

The purpose of this study was to examine the influence of physical activity on cytokine production in healthy older males. Twelve males (six very active, six less active) ages 65 to 74 were recruited for this study. Blood was obtained at rest and serum concentrations for MIP-I a, IL-1 ra, IL-6 and IL-10 were measured. No difference was found in MIP-la and IL-Ira concentrations between the two groups. The serum concentration of IL-6 was significantly lower (p = 0.016) in the very active group compared to the less active group. The very active group had a significantly higher (p = 0.016) concentration of IL-10 compared to the less active group. The beneficial influence of physical activity on cytokine production is clinically important because of the role of IL-6 and IL-10 in disease development in older adults. Through influencing cytokine concentrations, our results provide further insights into the role of physical activity in attenuating the effects of aging. / School of Physical Education

Background: Colorectal cancer (CRC) is the second leading cause of Canadian cancer mortality. Inflammation is a fundamental risk factor in the aetiology of sporadic intestinal carcinoma. Reducing the frequency or duration of gastrointestinal inflammation may decrease CRC risk. Over 200 population studies demonstrate reduced odds of developing CRC among physically active persons. Preliminary data suggests that regular exercise may slow CRC pathogenesis by decreasing and increasing intestinal expression of pro- and anti-inflammatory cytokines, respectively. This research was designed to further our understanding of how exercise influences the colonic cytokine milieu, even in the presence of immunoscenescent changes. Objectives: The objective of the first experiment (Study #1) was to compare cytokine and apoptotic protein expression in intestinal lymphocytes (IL) at baseline and in response to acute exercise-induced oxidant stress in both young and older C57BL/6 female mice. A second objective (Study #2) was to examine the effect of exercise training on the expression of pro- and anti-inflammatory cytokines and pro- and anti-apoptotic proteins in IL of older C57BL/6 female mice under ???resting??? conditions. The final objective (Study #3) was to compare the effect of acute exercise-induced stress on IL cytokine and apoptotic protein expression in trained versus untrained older C57BL/6 mice. Methods: Immediately following sacrifice, plasma was collected from the mice and stored (-80??C) until corticosterone and 8-iso-PGF2?? assessment by enzyme immunoassay. Soleus and plantaris skeletal muscles were excised and frozen in liquid nitrogen (-80??C) until spectrophotometric assessment of cytochrome c oxidase (CO) activity. Finally, the entire mouse intestinal compartment was removed and IL lysates were prepared for flow cytometric analysis of percent apoptosis (% Annexin V+ IL) and for western blot analysis of pro-inflammatory (TNF-??, IL-1??), pleiotropic (IL-6) and anti-inflammatory (IL-10) cytokine, and pro-(caspase-3, -7) and anti-(Bcl-2) apoptotic protein expression. Results: Findings from Study #1 indicate that, in mice, acute exercise increases caspase-3 (IMM and 2Hr groups vs. SED; p<0.05) and TNF-?? (IMM vs. SED and 2Hr groups; p<0.001), and decreases Bcl-2 (IMM and 2Hr groups vs. SED; p<0.01) expression in intestinal lymphocytes. Furthermore, IL expression of Bcl-2 was lower (p<0.001) and % Annexin V+ IL was higher (p<0.05) in the older vs. young mice. The results from Study #2 indicate that trained older mice had lower (p<0.05) expression of TNF-?? and caspase-7 in IL, and lower (p<0.05) concentration of 8-iso-PGF2?? in plasma compared to sedentary untrained controls. Finally, Study #3 shows that older trained mice display increased expression of pro-(TNF-??) and anti-(IL-10) inflammatory cytokines and pro-apoptotic (caspase-3, caspase-7) proteins, and decreased expression of anti-apoptotic (Bcl-2) protein in IL after acute exercise challenge compared to older untrained controls. In both Study #1 & #3, the treadmill protocol induced stress: plasma corticosterone and 8-iso-PGF2?? were higher in mice sampled immediately after acute exercise relative to the no acute exercise (sedentary) condition. This exercise effect did not differ by age (Study #1) or by training (Study #3) condition. In addition, Study #2 & Study #3 showed elevations in cytochrome c oxidase activity following long-term training. Conclusion: Collectively, these results suggest that, in C57BL/6 female mice, IL expression of pro-apoptotic proteins and pro-inflammatory cytokines does not differ by age (young vs. older animals) in response to a single intense exercise bout. However, older mice display lower expression of ???protective??? anti-apoptotic proteins and a higher percentage of early apoptotic IL compared to young mice. Additionally, long-term exercise may protect the bowel from inflammation by reducing inflammatory cytokine and apoptotic protein expression under ???resting??? (no stress) conditions. Finally, long-term training preserves the IL cytokine and apoptotic protein responses in older mice to a magnitude similar to that previously described in young mice. Alternatively, older untrained mice display reduced responsiveness to acute treadmill exercise, suggestive of immunosenescence.

In mice infected with 10$ sp4$ Giardia muris cysts, a peak lymphocyte proliferation in the spleen and Peyer's patches in response to Giardia extract occurred during the elimination and latent phases, respectively. This shows that the Peyer's patch cells are more responsive than the spleen to Giardia infection. Th2-type cytokines produced by Peyer's patch cells may play a protective role during the latent and acute phases. Th1-type cytokines may contribute to this production during the elimination phase. Cytokine production in response to Giardia extract in vitro was observed in mice immunized with this extract, but not in control mice. Therefore, Giardia antigen can induce cytokine production in vitro in a specific manner.

The incidence of preterm labor has risen over recent decades and preventative antibiotic treatment is ineffective. Associated with a 40% increased risk of preterm birth, bacterial vaginosis is characterized by a decrease in lactobacilli and increase in pathogenic bacteria in the vaginal flora. Ascent of bacterial products to the intrauterine environment stimulates cytokine and prostaglandin secretion from invading immune cells and gestational tissues. Probiotic lactobacilli modulate the immune responses in mouse macrophages and human placental trophoblast cells. The focus of this thesis was to determine the influence of Lactobacillus rhamnosus GR-1 (GR-1) on cytokines and prostaglandins which are part of the activated pathway in infection and/or inflammation mediated preterm labour. GR-1 increased amnion chemokine and reduced pro-inflammatory cytokine release. GR-1 elevated prostaglandin E2 release that was paralleled by an increase in mPGES2 expression. It is possible that t that GR-1 may enhance the host defense barriers of the amnion to pathogenic bacteria.