Increase In IL-17A Research Articles

Characterization of a new monoclonal antibody to human IL-17A (96.14)

Abstract Although IL-17A is made by CD4+ TH17 cells and there is an ever-increasing body of literature on these cells, other cells make IL-17A, including CD8+ (Tc17) and gamma-delta T cells, NK cells, and neutrophils. There are many factors that contribute to published findings of the percentage of cells producing IL-17A, including the activation or differentiation conditions, time course of activation, and antibody used for detection. It has been published that high levels of IL-17A are secreted by human PBMCs after anti-CD3/CD28-treatment alone for only 24 hrs. We have developed a new monoclonal Ab (clone 41802) that is specific for human IL-17A. The specificity of this Ab has been rigorously tested. Clone 41802 detects an increase in IL-17A in PMA/ionomycin-treated human PBMCs over resting cells by intracellular flow cytometry. This finding correlated with real-time PCR data in activated vs resting CD4+ PBMCs. This clone also detects IL-17A in a population of activated CD3+ PBMCs that is also positive for IL-22 and IL-23R by flow cytometry. Importantly, clone 41802 detects IL-17A in transfectant cells overexpressing human IL-17A, but not in cells overexpressing human IL-17F. The specificity of clone 41802 was further confirmed by western blot. In conclusion, clone 41802 is specific for human IL-17A. Although a larger percentage of IL-17A+ cells are detected in activated PBMCs than with other commercially available clones, this indicates an interesting biological finding, not a lack of antibody specificity.

The evolving systemic and local biomarker milieu at different stages of disease progression in rat collagen-induced arthritis

Rats with collagen-induced arthritis (CIA) were necropsied on 14 occasions from 4 days after induction to 27 days after disease onset to evaluate the kinetics of local (joint protein extracts) and systemic (serum) levels of inflammatory and pro-erosive factors. Systemic increases in α1 acid glycoprotein and KC/GRO together with systemic and local enrichment of interleukin (IL)-1β, IL-6, CCL2, transforming growth factor (TGF)-β and elevated IL-1α and IL-18 in joint extracts preceded the onset of clinical disease. Systemic upregulation of IL-1β, IL-6, TGF-β CCL2, RANKL and prostaglandin E2 (PGE2) during acute and/or chronic CIA coincided with systemic leukocytosis and a CD4+ T-cell increase in blood and spleen. In contrast, progression of joint erosions during clinical CIA was associated with intra-articular increases in IL-1α/β, IL-6, IL-18, CCL2, KC/GRO and RANKL, and a dramatic decline in osteoprotegerin (OPG). These data indicate that systemic and local events in inflammatory arthritis can be discrete processes, driven by multiple cellular and humoral mediators with distinct temporospatial profiles.

Mitochondrial involvement in transhemispheric diaschisis following hypoxia–ischemia: Clomethiazole-mediated amelioration

Mitochondria play a central role in both the physiological and pathophysiological regulation of cell survival/death. Increasing evidence places mitochondrial dysfunction at the center of many neuropathological conditions. The present study investigates the extent of mitochondrial dysfunction in cortical, hippocampal and cerebellar tissues in a rat model of hypoxia–ischemia (HI). We hypothesized that; mitochondrial dysfunction in situ may be prevented by treatment with clomethiazole (CMZ), a GABAA receptor agonist. Assessment of mitochondrial FAD-linked respiration at both 1- and 3-day post-HI revealed a marked decrease in activity from ipsilateral cortical and hippocampal regions (P<0.001). In addition, small changes were seen in contralateral cortical and hippocampal tissues as well as in the cerebellum at 3-days (P<0.05). Assessment of the mitochondrial electron transport chain (complexes I–V), and mitochondrial markers of integrity (citrate synthase) and oxidative stress (aconitase) confirmed mitochondrial impairment in ipsilateral regions following HI. Complexes I, II–III, V and citrate synthase were also impaired in contralateral regions and cerebellum 3-days post-HI. Treatment with CMZ (414 mg/kg/day via minipumps) provided marked protection to all aspects of neuronal tissue assessed. Circulating cytokine (interleukin [IL]-1α, IL-1β, tumor necrosis factor [TNF]-α, granulocyte macrophage colony-stimulating factor [GM-CSF], IL-4 and IL-10) levels were also assessed in these animals 3-days post-HI. Plasma IL-1α, IL-1β, TNF-α and GM-CSF levels were significantly increased post-HI. Treatment with CMZ ameliorated the increases in IL-1α, IL-1β, TNF-α and GM-CSF levels while increasing plasma IL-4 and IL-10 levels. This study provides evidence of the extent of mitochondrial damage following an HI-insult. In addition, we have shown that protection afforded by CMZ extends to preservation of mitochondrial function and integrity via anti-inflammatory mediated pathways.

In vitro and in vivo comparison of dermal irritancy of jet fuel exposure using EpiDerm™ (EPI-200) cultured human skin and hairless rats

The purpose of this study was to evaluate an in vitro EpiDerm™ human skin model (EPI-200) to study the irritation potential of jet fuels (JP-8 and JP-8+100). Parallel in vivo studies on hairless rats on the dermal irritancy of jet fuels were also conducted. Cytokines are an important part of an irritation and inflammatory cascade, which are expressed in upon dermal exposures of irritant chemicals even when there are no obvious visible marks of irritation on the skin. We have chosen two primary cytokines (IL-1α and TNF-1α) as markers of irritation response of jet fuels. Initially, the EPI-200 was treated with different quantities of JP-8 and JP-8+100 to determine quantities which did not cause significant cytotoxicity, as monitored using the MTT assay and paraffin embedded histological cross-sections. Volumes of 2.5–50 μl/tissue (∼4.0–78 μl/cm 2) of JP-8 and JP-8+100 showed a dose dependent loss of tissue viability and morphological alterations of the tissue. At a quantity of 1.25 μl/tissue (∼2.0 μl/cm 2), no significant change in tissue viability or morphology was observed for exposure time extending to 48 h. Nonetheless, this dose induced significant increase in IL-1α and TNF-α release versus non-treated controls after 24 and 48 h. In addition, IL-1α release for JP-8+100 was significantly higher than that observed for JP-8, but TNF-α release after 48 h exposure to these two jet fuels was the same. These findings parallel in vivo studies on hairless rats, which indicated higher irritation levels due to JP-8+100 versus JP-8. In vivo, transepidermal water loss (TEWL) and IL-1α expression levels followed the order JP-8+100 > JP-8 > control. Further, in vivo TNF-α levels for JP-8 and JP-8+100 were also elevated but not significantly different from one another. In aggregate, these findings indicate that EPI-200 tissue model can be utilized as an alternative to the use of animals in evaluating dermal irritation.

Cytokine response of bovine mammary gland epithelial cells to Escherichia coli, coliform culture filtrate, or lipopolysaccharide

To define the cytokine response of a cultured mammary gland epithelial cell line (ie, Mac-T) when incubated with Escherichia coli or its products. Mac-T cells and E coli from cows with mastitis. Mac-T cells were incubated with E coli or its products. The cytokine response of Mac-T cells to these treatments was quantified by measuring mRNA content of interleukin (IL)-1alpha, IL-1beta, IL-8, and tumor necrosis factor (TNF)-alpha by use of a quantitative reverse transcriptase-polymerase chain reaction assay. The amount of TNF-alpha secreted was also measured. Treatment with E coli or its products resulted in significant increases in IL-1alpha, IL-8, and TNF-alpha mRNA content in Mac-T cells. This increase was reversible when culture filtrate was incubated with polymyxin B. The amount of IL-1beta mRNA in Mac-T cells increased only slightly over baseline after treatment with E coli or its products, but this increase was not diminished by incubation of E coli filtrate with polymyxin B. Incubation of Mac-T cells with E coli or its products resulted in increased amounts of IL1alpha, IL-8, and TNF-alpha mRNA. Inhibition of this response by incubation of culture filtrate with polymyxin B suggested that lipopolysaccharide was the main bacterial product that stimulated the cytokine response. The small increase in IL-1beta content in Mac-T cells incubated with E coli or its products suggested that this cytokine had a smaller role in the Mac-T cell response to E coli.

FK506 (Tacrolimus) Inhibition of Intracellular Production and Enhancement of Interleukin 1α through Glucocorticoid Application to Chemically Treated Human Keratinocytes

Purpose: Production of the proinflammatory cytokine interleukin (IL) 1α, which is stored in keratinocytes (KCs) and is multifunctional, may be enhanced by glucocorticoids. A study was made to confirm whether immunosuppressants such as the macrocyclic lactone FK506 (tacrolimus) possibly serve to modulate glucocorticoid- stimulated IL-1α production from chemically treated KCs. Methods: Usingcultured human KCs, the effects of FK506 on the production of IL-1α treated with chemicals (trinitrobenzene sulfonic acid sodium salt, TNBS) plus hydrocortisone were analyzed by ELISA and mRNA expression of IL-1α using RT-PCR. Results: Intracellular IL-1α in TNBS-treated human KCs was increased with a low concentration of 10^–10M of hydrocortisone. Further FK506 application inhibited significantly this increased production.The mRNA expression of IL-1α at various concentrations of chemicals was not remarkably different. Conclusions: FK506may control the increase in IL-1α with glucocorticoid in KCs, suggesting FK506 to suppress harmful effects of glucocorticoids such as steroid rosacea.

Morphological and immunological evidence of a unique selective production and endoplasmic reticular accumulation of interleukin-1α in rat peritoneal macrophages induced by Pseudomonas aeruginosa exotoxin A

The immunotoxicity of Pseudomonas aeruginosa exotoxin A (ETA) on macrophages was evaluated by incubating rat peritoneal macrophages (RPM) with 1–100 ng/ml ETA for 3–60 h. Although the overall changes in cell viability and DNA, RNA, and protein synthesis of the ETA-treated RPM (E-RPM) were reduced in a dose- and time-dependent manner, there was a transient but evident rebound in RNA and/or protein synthesis at 24–36 h post-incubation (HPI) at 1–50 ng/ml ETA. However, a more apparent enhancement appeared in RNA and protein synthesis at 36–48 HPI in 10 and 50 ng/ml E-RPM after normalized on the basis of viable cell. Most 50–100 ng/ml E-RPM underwent necrosis/apoptosis before 24 HPI. By 36 HPI, 41% of 10 ng/ml E-RPM remained viable but were full of cytoplasmic granules due to the accumulation of glycoprotein in segmentally dilated endoplasmic reticulum. Immunological staining of the granules revealed strong IL-1α but weak or no signals for IL-1β, IL-1 receptor antagonist, IL-6, and TNF-α. A time-dependent increase in IL-1α but no IL-1β was detected in cell lysate of 10 ng/ml E-RPM; however, neither IL-1α nor IL-1β was detected in culture supernatant. Thus, besides cytopathic and functional effects, ETA could induce a unique selective production and endoplasmic reticular accumulation of IL-1α in RPM.

Host immune response to Salmonella enterica serovar Typhimurium infection in mice derived from wild strains.

Studies of mouse models of endotoxemia and sepsis with gram-negative bacteria have shown that the host response is genetically controlled. Mice infected with the gram-negative bacterium Salmonella enterica serovar Typhimurium exhibit marked genetic differences in disease manifestation, and the wild-derived strain Mus musculus molossinus MOLF/Ei is extremely susceptible to S. enterica serovar Typhimurium. The kinetics of bacterial proliferation within the liver and the spleen and histological examination of tissue sections have suggested that MOLF/Ei mice do not succumb to infection because of overwhelming bacterial growth in the reticuloendothelial organs or massive tissue necrosis, as observed in other Salmonella-susceptible strains. MOLF/Ei mice respond normally to lipopolysaccharide (LPS) in vivo and in vitro, as determined by the production of tumor necrosis factor alpha and spleen cell mitogenesis. However, they have a unique cytokine profile in response to infection compared to that observed for other Salmonella-susceptible mice. There was increased expression of mRNA of the interleukin-1 alpha (IL-1 alpha) and IL-1 beta genes as the infection in the spleens and livers of MOLF/Ei mice progressed. Despite the fact that MOLF/Ei mice have the ability to respond to LPS and the fact that there are significant increases in IL-1 alpha and IL-1 beta mRNA, Nos2 in the spleen is not upregulated and nitrite production by spleen cells is reduced. At the central level, the inflammatory response is characterized by strong upregulation of the inhibitory factor kappa B alpha and Toll-like receptor 2 genes, two genes known to be regulated by LPS and IL-1 in the brain. The high levels of IL-1 expression in the spleens and livers of MOLF/Ei mice may have important implications for the activation of peripheral and central innate immune mechanisms.

Effect of JP-8 Jet Fuel on Molecular and Histological Parameters Related to Acute Skin Irritation

Organic chemicals such as jet fuels and solvents can cause skin irritation after dermal exposure. The molecular responses to these chemicals resulting in acute irritation are not understood well enough to establish safe exposure limits. Male F-344 rats were dermally exposed to JP-8 jet fuel for 1 h using Hill Top Chambers. Whole skin samples were collected at 0, 1, 2, 4, and 6 h after the beginning of the exposures, homogenized, and analyzed for interleukin (IL)-1α and inducible nitric oxide synthase (iNOS) protein and nitrite levels. IL-1α levels (determined by ELISA) ranged from ∼11 to 34% above the 0-h samples over the observed time period. At 1 and 2 h, significantly higher (p < 0.05) levels of IL-1α were detected when compared to the 0-h samples. Western blot analysis revealed significantly higher (p < 0.05) levels of iNOS at 4 and 6 h compared to 0-h samples. Increases in IL-1α and iNOS expression were also observed in the skin immunohistochemically. Nitrite concentrations in skin samples were measured to estimate nitric oxide production. Although nitrite concentrations in the skin increased ∼6–27% above the 0-h samples over the observed time period, no significant changes in nitrite levels were detected. Pathological changes in the skin following JP-8 exposure were evaluated histologically. Increased numbers of granulocytes were observed infiltrating the skin at 2 h and were more prominent by 6 h. These data show that a 1-h exposure to JP-8 results in a local inflammatory response, which can be detected by changes in molecular and histological parameters.

Changes in serum levels of cytokines in mice injected with an immunostimulator C3bgp isolated from Cuscuta europea

The effect of C3 binding glycoprotein (C3bgp), isolated from Cuscuta europea seeds on induction of in vivo cytokine synthesis was investigated. Different groups of mice were stimulated with 30 μg C3bgp per mouse, injected intraperitoneally. The quantitative determination of IL-1α, IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ was performed in mouse sera by ELISA. The quantities of these cytokines were measured at different hours: 1, 2, 3, 4, 5, 6, 7, and 24 h after injection. No significant changes in serum level of IL-2, IL-4 and TNF-α in experimental animal groups were found. A little increase of IL-1α, moderate elevation of IL-10 and IFN-γ (5- to 6-fold more) and strong release, more than 10-fold of IL-6 in sera of C3bgp-treated mice were detected. The results obtained from C3bgp stimulated cultures of mouse peritoneal macrophages and mouse splenocytes suggest that C3bgp binds to mouse peritoneal macrophages and induces production mainly of IL-6, followed by IFN-γ and in a very low degree of IL-1α and IL-10. Based on the results presented, we conclude that the increased level of IL-6 was the basic after injection of C3bgp and that the mouse macrophages were the major cell targets for the C3bgp effect.

The popliteal lymph node response to streptozotocin is under type 1, MHC class-I restricted, CD8 + T-cell control

The popliteal lymph node (PLN) assay has been proposed to predict the ‘autoimmunogenic’ potential of xenobiotics. A better understanding of the processes involved in PLN responses is needed to establish the value of this assay for preclinical safety evaluation. In order to determine whether PLN responses involve CD4 + or CD8 + T-cells, the effects of streptozotocin (STZ), a prototypic immunotoxic compound, were analyzed after injection into the hind footpad of C57 BL/6 mice and major histocompatibility complex (MHC) class I or II deficient mice. The involvement of type 1 or type 2 cell control on the production of cytokine mRNAs was analyzed in lymph node cells by quantitative RT-PCR, together with the analysis of a wide range of cytokine mRNAs after STZ injection (IL-1α, IL-1β, TNF-α, IFN-γ, IL-2, IL-2 receptor, IL-4, IL-5, IL-6, IL-10 and IL-12). We have found that mice depleted in CD8 + T-cells did not respond to STZ, whereas mice depleted in CD4 + T-cells exhibited the expected positive PLN responses, with increased weight and cellularity indices. STZ induced a low production of interleukin (IL)-2 mRNAs, a mild increase in IL-1α and IL-6 mRNAs production, and a dramatic increase in IFN-γ, IL-1β, TNF-α, IL-12 and IL-2 receptor mRNAs, which correlated with positive PLN responses. No effects on IL-4, IL-5 and IL-10 mRNAs synthesis were noted. In CD8 + T-cell deficient mice, there was no production of IFN-γ or IL-6 mRNAs. These results suggest that PLN responses to STZ are under the control of type 1, MHC class-I-restricted, CD8 + T-cells. This is in accordance to the known physiopathology of STZ-induced diabetes. Additional studies are necessary to establish the mechanism of CD8+ T-cell activation.

Rhinovirus Regulation of IL-1 Receptor Antagonist In Vivo and In Vitro: A Potential Mechanism of Symptom Resolution

Rhinovirus (RV) upper respiratory tract infections are prototypic transient inflammatory responses. To address the mechanism of disease resolution in these infections, we determined if RV stimulated the production of the IL-1 receptor antagonist (IL-1ra) in vivo and in vitro. In contrast to IL-1alpha and IL-1beta, immunoreactive IL-1ra was readily detected in the nasal washings of normal human volunteers. Symptomatic RV infection caused a small increase in IL-1alpha, a modest increase in IL-1beta, and an impressive increase in IL-1ra. Maximal induction of IL-1alpha and IL-1beta was transiently noted 48 h after RV infection. In contrast, maximal induction of IL-1ra was prolonged appearing 48-72 h after RV infection. These time points corresponded to the periods of peak symptomatology and the onset of symptom resolution, respectively. Western analysis of nasal washings demonstrated that RV stimulated the accumulation of intracellular IL-1ra type I in all and secreted IL-1ra in a subset of volunteers. Unstimulated normal respiratory epithelial cells contained intracellular IL-1ra type I mRNA and protein. RV infection increased the intracellular levels and extracellular transport of this IL-1ra moiety without causing significant changes in the levels of IL-1ra mRNA. IL-1ra may play an important role in the resolution of RV respiratory infections. RV stimulates epithelial cell IL-1ra elaboration, at least in part, via a novel translational and/or posttranslational mechanism.

Cytokine mRNA expression in intestinal tissue of interleukin-2 deficient mice with bowel inflammation

Background—Mice deficient in interleukin-2 (IL-2) develop inflammatory bowel disease resembling ulcerative colitis in humans. Recent studies provided evidence that αβ T cells, particularly CD4 T cells, rather than B cells,...

Influence of smoking on the expression of various cytokines in murine bronchoalveolar lavage fluid cells

ABSTRACT The cytokine network plays an important role in the pathogenesis of allergic asthmatic lung. As the influence of smoking on cytokine expression should be considered in delineating the cytokine network, the effects of a single exposure and chronic exposure to smoke on the number and cytokine expression of bronchoalveolar lavage fluid (BALF) cells were evaluated. From a total of 126 BALB/c mice, BALF cells were obtained and analyzed using the quantitative reverse transcription-polymerase chain reaction technique (RT-PCR). The bodyweights of chronic smoking mice were found to be lower when compared to those mice that had not been exposed to smoke. The total number of BALF cells increased after smoking without significant differences in cell classification. Spontaneous mRNA expression of interleukin-1α (IL-1α), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and transforming growth factor-β (TGF-1β) was detected in all cases. The time courses of their expression patterns after exposure to smoke were similar between the chronic and single smoking mice, except for TGF-β. The levels of IL-1β, IL-1β and TGF-β mRNA increased immediately after the exposure to smoke in chronic smoking mice, whereas the levels of TGF-β mRNA increased 2 h after exposure in the single smoking mice. Moreover, the increase of IL-1α and TGF-1β mRNA in the early phase after exposure was exaggerated in chronic smoking mice. Thus, repeated exposure to smoke may have caused some alterations in the expression mechanism of cytokines such as TGF-β and IL-1α in BALF cells, while it seemed to cause a repeated pattern of acute inflammation after each exposure. In the evaluation of cytokine expression in BALF cells in smokers with various lung diseases, it is recommended that before taking samples a sufficient time interval after the last exposure to smoke be allowed to avoid the effect of acute inflammation caused by smoking.

Cloning bovine cytokine cDNA fragments and measuring bovine cytokine mRNA using the reverse transcription-polymerase chain reaction

Bovine cytokine-specific primers and the reverse transcription-polymerase chain reaction (RT-PCR) were used to clone cDNA fragments that were specific for bovine IL-1α, IL-1β, IL-2, and IFN-γ. Specificity of the cDNA fragments was verified by sequence analysis based on known bovine IL-1α, IL-1β, IL-2, and IFN-γ gene sequences. In addition, RT-PCR was used to monitor cytokine mRNA expression in concanavalin A (Con A) and lipopolysaccharide (LPS)-stimulated bovine peripheral blood mononuclear cells (PBMC), and the results were compared with those obtained by measuring PBMC cytokine secretion using biologic assays. IL-1 activity in LPS-stimulated PBMC cultures was similar at 12 h and 24 h, although the activity decreased by approximately 40% at 48 h. IL-2 and IFN-γ activity in supernatants of Con A-stimulated PBMC cultures was low at 12 h and reached maximum levels at 48 h. RT-PCR transcript analysis detected an increase in IL-1α, IL-1β, IL-2, and IFN-γ mRNA expression that was usually correlated with the detection of these soluble cytokines by the bioassays. These results indicate that RT-PCR is a sensitive and effective method of obtaining cDNA probes and that this technique can be used to monitor bovine cytokine mRNA expression.

Skin 2TM: An in vitro model to assess cutaneous immunotoxicity

The skin serves as a complex barrier protecting the internal environment against external factors (e.g. bacteria, viruses, environmental toxins and UV light). For the epidermis to produce the most effective toxicological, immunological and biochemical barrier, the major cell types of the epidermis (i.e. keratinocytes) and in the dermis (i.e. fibroblasts) must function together in a dynamic integrated fashion. Furthermore, epidermal-dermal intercellular biochemical signals such as interleukins (IL), cytokines and other growth factors provide the skin with local homoeostatic signals to ensure the skin's immune integrity in response to a variety of environmental insults. Other investigators have shown that exposure of the skin to long-wave ultraviolet light (UVA) and mid-range ultraviolet light (UVB) can alter epidermal immune functions, including epidermal cytokine (e.g. IL-1, IL-6, TNF-α, IL-10 and GM-CSF) levels. The studies reported here use a co-culture system of dermal fibroblasts and well differentiated epidermal layers with an attached stratum corneum to form an in vitro human skin analogue. Baseline endogenous levels of IL-1α and tumour necrosis factor-α (TNF-α) were detected by using commercially available ELISA kits. The tissue substrates were exposed to UVA/UVB light (280–400 nm). The UV light was administered by a Dermsol 3 mercury halide solar simulator configured with filters to remove energy levels below 280 nm and above 410 nm. Skin tissue irradiated at 4J/cm 2 revealed a significant increase in IL-1α and TNF-α in comparison with non-UV irradiated tissue. Additional experiments revealed that the topical administration of indomethacin (0.1 to 10mg/ml) to the skin tissue ameliorated the up-regulation of these immune cytokines following UV irradiation. The use of such an in vitro co-culture system may provide researchers with a unique method to quantify mechanistically immunotoxicological events in the skin after exposure to ultraviolet light.

Interleukin-6 and interleukin-1α production is associated with antigen-induced late nasal response

Background: Cytokines such as tumor necrosis factor (TNF)-α interleukin (IL)-1α IL-6 and granulocyte macrophage-colony stimulating factor (GM-CSF) are able to potentiate allergic inflammation and seem to be implicated in the development of the late allergic reaction. Methods: To study the time course of cytokine production, sequential lavages were performed after nasal allergen challenge. Thirteen patients with allergic rhinitis and four healthy subjects were exposed to grass pollen (n = 6 and n = 2, respectively) or dust mite allergen (n = 7 and n = 2, respectively). Results: Among the patients with allergic rhinitis, a single early response (single responders) developed in four, eight exhibited a dual response (dual responders) and one patient as well as the four healthy subjects did not respond. In addition to the measurement of IL-1 α, IL-6, TNF-α and GM-CSF concentrations by ELISA, the release of histamine, tryptase, and cosinophil cationic protein was also evaluated by radioimmunoassay performed on nasal lavage fluids. Concerning meditor levels in nasal lavage fluid, neither histamine release nor cytokine elevation were noted in healthy subjects. As previously described, histamine, tryptase and eosinophil cationic protein were released in single and dual responders. Concerning cytokines, TNF-α was undetectable in the majority of nasal lavages and an increase in GM-CSF concentration was occasionally observed whatever the type of response. In contrast, an increase in IL-1α and IL-6 levels was observed for dual responders during the early period (12.6 ± 3 and 9.2 ± 2 pg/ml, respectively; p < 0.01 (in both cases) and at a higher level during the late period (14.5 ± 4, p not significant and 16.7 ± 8 pglml, respectively; p < 0.01) when compared with baseline values (72 ± 2.2 and 2 ± 0.7 pg/ml respectively). For single responders IL-1α and IL-6 secretion was detected mainly during the early period. Conclusion: These data suggest a role for IL-1 a in the induction and perennisation of the inflammatory reaction in allergic rhinitis; whereas the role of IL-6 remains to be investigated.

Thymulin Modulates Cytokine Release by Peripheral Blood Mononuclear Cells: A Comparison between Healthy Volunteers and Patients with Systemic Lupus Erythematosus

Thymulin is a nonapeptide hormone isolated from the thymus gland. It has immunomodulatory effects which have not yet been well defined. Its major actions have been shown to be on T-cells and their immature precursors. In this study, thymulin was tested in vitro for its effect on the release of IL-1 alpha, IL-2, IL-6 and TNF alpha from peripheral blood mononuclear cells (PBMC) obtained from normal volunteers and patients with active systemic lupus erythematosus (SLE). In our experiments, PBMC (stimulated with LPS or PHA) were cultured for 24 h in the presence of 1,100 or 1,000 ng/ml of thymulin. Supernatants were subsequently assayed for cytokine activities using commercially available ELISA (IL-2, IL-6 and TNF alpha) and RIA (IL-1 alpha) kits. Thymulin (1 ng/ml) resulted in a significant (p < 0.01) increase in IL-1 alpha in the volunteers and a significant (p < 0.05) inhibition of this cytokine at all dose levels tested in SLE patients, whose basal levels of IL-1 alpha were significantly (p < 0.05) higher. Thymulin significantly (p < 0.05) inhibited IL-2 only in SLE patients at 1,000 ng/ml. At all dose levels tested, thymulin significantly (p < 0.01) inhibited IL-6 in volunteers, and, only at 1,000 ng/ml, it significantly (p < 0.05) inhibited it in patients with SLE. At the 1,000 ng/ml dose level, TNF alpha was significantly (p < 0.05) inhibited in both volunteers and SLE patients, whose basal levels of this cytokine were significantly (p < 0.05) higher.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum levels of helper factors (IL-1α, IL-1β and IL-6), T-cell products (sCD4 and sCD8), sIL-2R and β2-microglobulin in patients with B-CLL and benign B lymphocytosis

Chronic B-lymphocytic leukemia (B-CLL) cells may be regulated by immune functions. In an attempt to analyze such functions, helper factors (IL-1α, IL-1β and IL-6), T-cell products (sCD4 and sCD8) and sIL-2R and β 2-microglobulin were measured in serum of patients at different stages of the disease. Patients were classified as having monoclonal lymphocytosis of undetermined significance (MLUS), stable or progressive B-CLL respectively. A significant, but modest, increase of IL-1α was found in B-CLL as well as in MLUS patients whereas IL-6 levels were increased in MLUS only. sCD8 levels were increased both in MLUS and B-CLL but augmented sCD4 concentrations were found statistically significant only in progressive B-CLL. β 2-microglobulin and sIL-2R were related to the extent of the monoclonal B-cell fraction. The data indicate an increased T-suppressor activity in both MLUS and B-CLL patients and a selective increase of helper T-cell activity in progressive B-CLL. A possible immunoregulatory influence of helper T cells on disease progression is discussed.