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PubMed2001

Differential expression of vasoactive intestinal polypeptide receptor 1 and 2 mRNA in murine intestinal T lymphocyte subtypes.

Neuropeptides may exert a variety of effects on the immune cells at both systemic and mucosal immune sites. The immunoregulatory properties refer to the ability of physiological signals and pathways to influence various immune functions. Vasoactive intestinal polypeptide (VIP), a neuropeptide present in high concentration in gut, was studied for its production and receptor expression in intraepithelial and lamina propria T lymphocytes of mouse intestine. Using reverse transcription-polymerase chain reaction (RT-PCR) analysis, it was demonstrated that VIP receptor 1 (VIPR1) was constantly expressed in intraepithelial and lamina propria T lymphocytes from both small and large intestine. In contrast, VIPR2 was identified only in T cells from small intestine. Further studies on purified subpopulations of T lymphocytes indicated the existence of VIPR2 in CD8(+) T cells, but not CD4(+) and CD4CD8 double negative T cells, although all these three subpopulations displayed VIPR1. In addition, VIPR1 mRNA was detected in splenic T lymphocytes, but no signal was obtained for VIPR2 mRNA, even after stimulation of the cells with anti-CD3(epsilon)-chain mAb, phorbol 12-myristate 13-acetate (PMA) and/or VIP. The presence of VIP receptor(s) on intestinal T lymphocytes was supported by the detection of VIP on the cell surface using dual colour immunoflowcytometry. In-vitro treatment with VIP resulted in a tendency towards an increased size of the VIP immunoreactive T cell population and significantly enhanced the average immunofluorescence intensity of the surface labelling. This indicates that the receptors are partially occupied by locally produced VIP in vivo and that more peptide molecules can be bound on the lymphocytes when needed, released and accumulated in higher concentration at the action sites. We failed to detect the expression of VIP mRNA in T lymphocytes, from either intestine or spleen. These observations support that VIP may be an important immune modulator in gut acting through specific receptors on T lymphocytes. The differential mRNA expression of VIP receptor subtypes in cells with different phenotypes and in different immune compartments may suggest diverse regulatory roles of the neuropeptide in immune responses.

Animals↗
PubMed2026

Profiling tumor immune microenvironment of epithelial ovarian carcinoma.

BACKGROUND: Epithelial ovarian carcinoma (EOC) comprises five main histological subtypes: high-grade serous (HGSOC), low-grade serous (LGSOC), clear cell (CCOC), mucinous (MOC), and endometrioid (ENOC). Each histotype harbors specific genomic alterations and clinical outcome. Few studies systematically compared the tumor immune microenvironment across the five subtypes. METHODS: We performed 7-plex (CD45, CD8, CD68, CD163, FoxP3, CD20, and cytokeratin) sequential immunohistochemistry on a clinically annotated tissue microarray including 139 EOC representing the five subtypes and 26 borderline tumors (serous and mucinous). Digital pathology was used to quantify immune cell abundance, their spatial distribution (stroma vs tumor core), and correlation with survival. RESULTS: Immune cells were dominated by macrophages and more abundant in the stroma than tumor core across the five subtypes, consistent with immune excluded pattern. Compared to HGSOC, CCOC displayed the highest infiltration by CD45+ leukocytes and CD68+ macrophages, particularly M2-like CD163+ cells, suggesting a macrophage-rich, immunosuppressive phenotype. LGSOC exhibited the highest infiltration by intraepithelial FoxP3+ regulatory T cells. Comparison of borderline tumors with invasive carcinoma (LGOSC and MOC) revealed that malignant progression is accompanied by loss of CD8+ T cells, enrichment in regulatory T cells and increase of CD163+/CD68+ ratio, consistent with immune evasion during tumorigenesis. There was a trend toward better survival in HGSOC highly infiltrated by lymphocytes, either intraepithelial (CD8+ and FoxP3+) or stromal (FoxP3+ and CD20+). CONCLUSIONS: EOC is characterized by histotype-specific immune milieux defined by macrophage dominance, epithelial immune exclusion and dynamic immune remodeling during progression from borderline tumors to invasive carcinomas.

Humans↗
PubMed2006

HIV-specific T cell immunity across the entire HIV genome in Chinese men who have sex with men.

BACKGROUND: Man who has sex with man (MSM) is one of the high risk groups for spreading HIV/AIDS. It was reported that the most prevalent human immunodeficiency virus type 1 (HIV-1) strain among MSM is subtype B; however, T cell immunity remains unknown across the HIV-1 B genome in this population. METHODS: Using Elispot assay with synthetic peptides spanning the sequence of HIV-1 consensus B, HIV-1-specific cytotoxic T-cell lymphocyte responses were quantified among 3 treated and 19 untreated HIV-1 infected MSM from Beijing, China. Cross-sectional association between viral loads and cellular immune responses were analyzed. RESULTS: Peptide pools corresponding to each HIV-1 protein were used for Env, Gag, Pol, Nef, Tat/Rev, Vpr/Vpu and Vif. The results showed that the magnitude of T cell responses in the 3 treated HIV(+) MSM group [median, 770 spot forming cells (SFCs) per 10(6) peripheral blood mononuclear cells (PBMCs)] might be significantly lower than that in the 19 untreated HIV(+) MSM group (median, 6175 SFCs per 10(6) PBMCs). Nef, Gag and Pol are the most frequently targeted HIV-1 antigens; and 16 subjects (73%) were identified with vigorous T cell immunity against each of these three proteins. The overall magnitude of T cell immunity closely related to its breadth (r = 0.72, P < 0.05) and was inversely but weakly associated with viral loads (r = -0.15). Further analysis showed that both Gag (r = -0.24) and Pol specific T cells (r = -0.12) contributed to this inverse association whereas Nef specific T cells showed no association with viral loads. CONCLUSIONS: The magnitude of HIV-1 specific T cells is inversely but weakly associated with viral loads among MSM; HIV-specific T cell responses against conservative sequences (Gag and Pol) are the main contributors to this association among Chinese HIV(+) MSM. These findings have important implications for vaccine design.

Adult↗
PubMed2001

Melatonin receptor subtype MT2 (Mel 1b) and not mt1 (Mel 1a) is associated with melatonin-induced enhancement of cell-mediated and humoral immunity.

Individuals of many vertebrate species undergo seasonal changes in immune function in addition to marked seasonal changes in reproductive, metabolic, and other physiological processes. Despite growing evidence that photoperiod mediates seasonal changes in immunity, little is known regarding the neuroendocrine mechanisms underlying these changes. Enhanced immune function in short days is correlated with increased duration of nightly melatonin secretion, and recent studies indicate that melatonin can act directly on immune cells to enhance immune function. It remains unknown, however, which melatonin receptor subtype mediates immune enhancement by melatonin. The present study examined the contribution of specific melatonin receptor subtypes, mt1 (Mel 1a) and MT2 (Mel 1b), in mediating melatonin-induced enhancement of cell-mediated and humoral immune function in mice. Melatonin enhanced both splenocyte proliferation and anti-keyhole limpet hemocyanin (KLH) IgG concentrations in both wild-type (WT) and mice lacking a functional gene for melatonin receptor mt1 (mt1 -/-), suggesting that the mt1 receptor does not mediate these responses. In addition, luzindole, an MT2 receptor antagonist, attenuated melatonin-induced enhancement of splenocyte proliferation in both WT and mt1 -/- mice. Taken together, these results suggest that receptor subtype mt1 is not necessary for mediating melatonin-induced enhancement of immune function and provide the first evidence for a specific melatonin receptor subtype, MT2, that may be involved in melatonin-induced immune enhancement.

Animals↗
PubMed1994

Effects of selective type I and II adrenal steroid agonists on immune cell distribution.

Adrenal steroids exert their effects through two distinct adrenal steroid receptor subtypes; the high affinity type I, or mineralocorticoid, receptor and the lower affinity type II, or glucocorticoid, receptor. Adrenal steroids have well known effects on immune cell distribution, and although both type I and II receptors are expressed in immune cells and tissues, few data exist on the relative effects mediated through these two receptor subtypes. Accordingly, we administered selective type I and II adrenal steroid receptor agonists to young adult male Sprague-Dawley rats for 7 days and then measured immune cell distribution in the peripheral blood and spleen. Results were compared with those of similar studies using the naturally occurring glucocorticoid of the rat, corticosterone, which binds both type I and II receptors. The majority of the well characterized effects of adrenal steroids on peripheral blood immune cells (increased neutrophils and decreased lymphocytes and monocytes) were reproduced by the type II receptor agonist, RU28362. RU28362 decreased the numbers of all lymphocyte subsets [T-cells, B-cells, and natural killer (NK) cells] to very low absolute levels. The largest relative decrease (i.e. in percentage) was seen in B-cells, whereas NK cells exhibited the least relative decrease and actually showed a 2-fold increase in relative percentage during RU28362 treatment. Similar to RU28362, the type I receptor agonist, aldosterone, significantly reduced the number of lymphocytes and monocytes. In contrast to RU28362, however, aldosterone significantly decreased the number of neutrophils. Moreover, aldosterone decreased the number of T-helper cells and NK cells, while having no effect on the number of B-cells or T-suppressor/cytotoxic cells. Corticosterone at physiologically relevant concentrations had potent effects on immune cell distribution, which were indistinguishable from those of the type II receptor agonist, RU28362. Taken together, these results indicate that effects of adrenal steroids on immune cell distribution are dependent on the receptor subtype involved as well as the specific cell type targeted. These factors allow for varied and complex effects of adrenal steroids on the immune system under physiological conditions.

Aldosterone↗
PubMed1994

HLA class II molecules (HLA-DR, -DP, -DQ) on cells in the human CNS studied in situ and in vitro.

Human leucocyte antigen (HLA) class II molecules expressed by antigen-presenting cells (APC) are major restriction elements in the interaction between APC and T cells of the CD4+ subtype. To explore the immune accessory function of cells in the central nervous system (CNS), we studied the expression of HLA-DR, -DP, and -DQ molecules on CNS cells in situ and in vitro. Reactive microglia and perivascular cells in multiple sclerosis lesions expressed all three HLA class II molecules, whereas microglia in the normal CNS expressed HLA-DR only. All three HLA class II molecules were up-regulated on cultured microglia after stimulation with interferon-gamma (IFN-gamma). Microglial stimulation of allogeneic CD4+ T cells in a mixed lymphocyte reaction (MLR) was effectively blocked using anti-HLA-DR monoclonal antibodies (mAb) but not using anti-HLA-DQ mAb. HLA class II-positive astrocytes and endothelial cells were not identified in normal or diseased CNS. Cultured astrocytes stimulated with IFN-gamma could, however, be induced to express HLA class II antigens of all subtypes, although great variability was observed between different donors. Our results indicate that although both microglia and astrocytes are capable of expressing all HLA class II subtypes in vitro, subtype expression differs between normal and pathological states in situ. Such selective expression may be associated with functional properties.

Adult↗
PubMed2006

Induction of local and systemic immune reactions following infection of turkeys with avian Metapneumovirus (aMPV) subtypes A and B.

Most of the studies regarding the immunopathogenesis of avian Metapneumovirus (aMPV) have been done with subtype C of aMPV. Not much is known about the immunopathogenesis of aMPV subtypes A and B in turkeys. Specifically, local immune reactions have not been investigated yet. We conducted two experiments in commercial turkeys. We investigated local and systemic humoral and cell mediated immune reactions following infection with an attenuated vaccine strain of aMPV subtype B (Experiment I) and virulent strains of aMPV subtypes A and B (Experiment II). Turkeys infected with virulent aMPV strains developed mild respiratory signs while birds inoculated with the attenuated aMPV did not show any clinical signs. Virus neutralizing antibodies were detected locally in tracheal washes and systemically in serum as soon as 5-7 days post aMPV infection (PI) independent of the strain used. Virus neutralizing antibody titres peaked at 7 days PI and then antibody levels declined. The peak of serum ELISA antibody production varied between infected groups and ranged from 14 and 28 days PI. All aMPV strains induced an increase in the percentage of CD4+ T cell populations in spleen and Harderian gland at days 7 or 14 PI. Furthermore, as shown in Experiment I, infection with the attenuated aMPV-B strain stimulated spleen leukocytes to release significantly higher levels of interferons (IFNs), interleukin-6 and nitric oxide in ex vivo culture in comparison to virus-free controls up to 7 days PI (P<0.05). As detected by quantitative real time RT-PCR in Experiment II, infection with virulent aMPV induced an increased IFNgamma expression in the Harderian gland in comparison to virus-free controls. IFNgamma expression in the spleen varied between aMPV strains and days PI. Overall, our study demonstrates that aMPV subtypes A and B infection induced humoral and cell mediated immune reactions comparable to subtype C infections. We observed only temporary stimulation of serum virus neutralizing antibodies and of most of the local immune reactions independent of the aMPV strain used. The temporary character of immune reactions may explain the short duration of protection against challenge following aMPV vaccination in the field.

Animals↗
PubMed2025

m6A regulator-based molecular classification and hub genes associated with immune infiltration characteristics and clinical outcomes in diffuse gliomas.

BACKGROUND: m6A methylation modification is a new regulatory mechanism involved in tumorigenesis and tumor-immunity interaction. However, its impact on glioma immune microenvironment and clinical outcomes remains unclear. METHODS: Comprehensive expression profiles of 18 m6A regulators were used to identify molecular subtypes exhibiting distinct m6A modification patterns in 1673 glioma samples sourced from public datasets. A multi-genes signature was constructed for predicting clinical outcomes and response to immunotherapy in glioma patients. Immunohistochemistry and cellular experiments were performed for validation. RESULTS: Two m6A subtypes of gliomas were identified. The m6A-low-risk subtype was characterized by paucity of immune infiltrates; While the m6A-high-risk subtype had higher abundances of multiple immune cells including lymphocyte and macrophage as well as increased expression of PD-L1, corresponding to an immunosuppressive phenotype. The m6A-high-risk subtype had poorer survival than the m6A-low-risk subtype in both the glioblastoma and lower grade gliomas cohorts. Eight m6A-related hub genes of high prognostic significances were identified and selected for developing a scoring signature termed as m6Ascore. Elevated m6Ascore indicated worse survival for glioma patients under standard care, but showed enhanced response to immunotherapy. Moreover, we demonstrated that overexpression of FTO, a m6A demethylase, inhibited the expressions of m6A-related hub genes (PTX3, SPAG4), impaired glioma cell viability and reduced macrophage chemotaxis. CONCLUSION: This work develops an immune- and clinical-relevant m6A subtyping and a scoring model, which enhances our understanding of the role of m6A modification in regulating immune infiltration microenvironment in gliomas and helps to identify patients who are more likely to benefit from immunotherapy.

Humans↗
PubMed1992

[D-Ala2]deltorphin I binding and pharmacological evidence for a special subtype of delta opioid receptor on human and invertebrate immune cells.

The effects of the opioid neuropeptide [D-Ala2]deltorphin I, isolated from amphibian skin, on immunoregulatory activities were studied in representatives of vertebrates and invertebrates. The high potency of this compound parallels that of [Met]enkephalin, which was previously demonstrated in vertebrate plasma and invertebrate hemolymph. The addition of [D-Ala2]deltorphin I at 10(-11) M to human granulocytes or immunocytes of the mollusc Mytilus edulis resulted in cellular adherence and conformational changes indicative of cellular activation. This value is in line with the concentrations obtained with [Met]enkephalin, tested in the presence of the specific neutral endopeptidase 24.11 inhibitor phosphoramidon, and this opioid's synthetic analog [D-Ala2, Met5]enkephalin which, like [D-Ala2]deltorphin I, is resistant to proteolytic degradation. Both ligands appear to be acting on the same population of immunocytes. The same relationship was estimated to exist in the insect Leucophaea maderae, in which the high viscosity of the hemolymph makes the quantification of reactive cells more difficult than in Mytilus. In addition, [D-Ala2]deltorphin I is as potent as beta-endorphin in affecting the proliferation of lymphocytes in response to mitogen. Saturation experiments with unlabeled ligands and the radioligands [3H][D-Ala2]deltorphin I and [3H][D-Ala2,Met5]enkephalinamide revealed the presence of two high-affinity binding sites on human granulocytes, one sensitive to the nonequilibrium delta opioid antagonist [D-Ala2,Leu5,Cys6]enkephalinamide and the other relatively insensitive. The results obtained with [D-Ala2]deltorphin I support the view that the special role played by endogenous [Met]enkephalin in immunobiological activities of vertebrates and invertebrates is mediated by a special subtype of delta opioid receptor.

Animals↗
PubMed2026

Molecular subtyping of adrenocortical carcinoma reveals distinct subtypes with prognostic and therapeutic implications.

Adrenocortical carcinoma (ACC) is a rare but aggressive malignancy with poor survival and limited treatment options. To comprehensively characterize its molecular landscape and identify clinically relevant subtypes, we performed an integrated genomic analysis - including whole-exome sequencing, RNA sequencing, and copy number variation profiling - on 61 Chinese patients with ACC. We identified recurrent mutations in TP53 (25%), CTNNB1 (15%), ZNRF3 (10%), and MEN1 (8%). Unsupervised clustering of transcriptomic data revealed four distinct molecular subtypes: cortisol-driven (CD, 14%), immune-suppressed (IS, 40%), cell cycle-altered (CCA, 22%), and immunomodulatory (IM, 24%). The CD subtype exhibited steroidogenic pathway activation; the IS subtype showed T cell receptor downregulation and the worst disease-free survival; the CCA subtype was marked by chromosomal instability and cell cycle gene overexpression; and the IM subtype displayed enriched immune signaling and favorable outcomes. Copy number analysis further uncovered focal amplifications (e.g. TERT, CDK4) and HLA-II deletions. This study establishes a novel molecular classification of ACC, providing a framework for subtype-specific therapeutic strategies, such as CDK4/6 inhibition for CCA and immunotherapy for IM tumors, while highlighting the clinical challenges of immune-cold IS tumors.

Humans↗
PubMed1989

[Immunologic changes in active pulmonary tuberculosis treated with a fuzheng guben pill].

This paper reports the changes of immunity in treatment of active pulmonary tuberculosis with Fuzheng Guben Pill (FGP). The chemotherapy group consisted of 11 cases of active pulmonary tuberculosis and was cured by streptomycin (SM) and isonicotinylhydrazide (INH). The FGP group consisted of 14 cases of active pulmonary tuberculosis and was cured by SM and INH in combination with FGP. After 60 days of treatment, the subtype T-cell mediated immunity in the FGP group was recovered to normal level. (OKT3: 46.07 +/- 6.92 to 54.86 +/- 8.74; OKT4: 36.14 +/- 4.79 to 41.00 +/- 4.13, etc). The chemotherapy group had no obvious immunological change after medication. It was shown that FGP had an immunological modulation in active pulmonary tuberculosis patients.

Drugs, Chinese Herbal↗
PubMed2006

Individual HIV type 1 envelope-specific T cell responses and epitopes do not segregate by virus subtype.

HIV-1 vaccines are often designed to target one or several virus subtype(s). They therefore include antigens (e.g., env or env/gag/pol) from each targeted subtype to elicit subtype-directed immunity. To determine if individual T cells respond to HIV-1 antigens in a subtype-directed manner, we selected four T cell hybridomas, each representative of a different immunodominant response toward a subtype B envelope. Hybridomas were tested for responses toward 20 subtype B envelope proteins and one protein each from subtypes A, C, and D. None of the hybridomas cross-reacted with all subtype B envelopes, yet three responded to a non-B protein. Core epitopes and flanking regions affected responsiveness. This lack of subtype-directed activity was corroborated by analyses of the Los Alamos database; like immune responses, epitope distributions were not dictated by subtype. Results highlight the difficulty of predicting immune responses based on subtype alone and encourage considerations of antigenic disparity in addition to subtype disparity during HIV-1 vaccine design.

Amino Acid Sequence↗
PubMed2004

Selective knock-down of P2X7 ATP receptor function by dominant-negative subunits.

Among the family of P2X ATP-gated cation channels, the P2X7 receptor is a homomeric subtype highly expressed in immune cells of the monocyte-macrophage lineage. We report here that the WC167-168AA mutation in the ectodomain of P2X7 produced nonfunctional subunits with strong dominant-negative effect on wild-type P2X7 receptors (77% inhibition with cotransfection of wild-type and mutant DNA at a ratio of 3:1). The C168A single mutant was also very effective in suppressing P2X7 receptor function (72% reduction at a DNA ratio of 3:1), indicating the major role played by the C168A mutation in this inhibition. The dominant-negative effect is selective; the mutant subunit did not suppress the function of other receptor-channel subtypes. The reduced current responses in cells coexpressing wild-type and dominant-negative subunits display wild-type characteristics in both agonist affinity and ionic selectivity, strongly suggesting that the heteromeric channels are functionally impaired. The mutant subunits also suppressed the P2X7-dependent pore formation as assessed by uptake of the propidium dye YO-PRO-1 (Molecular Probes, Eugene, OR) in response to 2',3'-O-(4-benzoyl)-benzoyl-ATP (BzATP) in transfected human embryonic kidney 293 cells. Native responses to BzATP as well as ATP-induced ethidium dye uptake were significantly knocked down (31 +/- 9% and 25 +/- 7% of control, respectively) in mouse macrophage cell line RAW264.7 transfected with the mutant subunits. Therefore, these dominant-negative subunits provide selective genetic tools to investigate the functional roles of native P2X7 receptors.

Animals↗
PubMed2001

Roles of CD4+ and CD8+ T cells in adjuvant activity of diesel exhaust particles in mice.

Through an imbalance in Th1 and Th2 cytokine profiles, diesel exhaust particles (DEP) are thought to induce Th2-dominated IgE and IgG1 production. However, the roles of CD4+ and CD8+ T-cell subtypes in the increased immune responses to antigen in mice exposed to DEP are unclear. In the present study, we investigated whether treatment with anti-CD4 or anti-CD8 mAb abrogated the adjuvant activity of DEP. On day -1 and day 1, each group of mice was injected intraperitoneally with anti-CD4, anti-CD8, or rat IgG (vehicle). On day 0, the mice were immunized with ovalbumin (OVA) or OVA plus DEP. After 3 weeks, each mouse was boosted with 10 microg of OVA alone. On day 7 after the first injection with OVA+DEP or OVA alone, the numbers of total, IA+, CD80+/IA+ and CD86+/IA+ cells in peritoneal exudate cells (PEC) were higher in OVA+DEP-immunized mice than in OVA-immunized mice. Depletion of CD8+ cells resulted in a modulation of the production of granulocyte-macrophage colony-stimulating factor, IL-12 and PGE(2) in peritoneal exudate fluid from OVA+DEP-immunized mice. On day 28, DEP injection markedly increased IL-4 production in the culture supernatants of spleen cells from CD4+ or CD8+-depleted mice. Depletion of CD8+ cells in OVA+DEP-immunized mice resulted in a decrease in IFN-gamma production compared with that in OVA-immunized mice. Adjuvant activity of DEP was observed in anti-OVA IgE, anti-OVA IgG1, anti-OVA IgG3, and total IgE production. Depletion of CD4+ T cells abrogated the adjuvant effect of DEP on anti-OVA IgE, and anti-OVA IgG1 production in plasma. However, depletion of CD8+ T cell inhibited the upregulated anti-OVA IgG3 production. These findings suggest that DEP injection may affect not only the function of CD4+ cells but also that of CD8+ T-cell subsets to modulate the synthesis of proinflammatory cytokine in PEC and type-1 and type-2 cytokine production in spleens.

Adjuvants, Immunologic↗
PubMed1983

Recovery from a viral respiratory tract infection. IV. Specificity of protection by cytotoxic T lymphocytes.

Immune spleen cells enhanced for influenza-specific cytotoxic activity after exposure to virus-infected stimulator cells in vitro effect recovery when transferred to nude and immunocompetent mice with influenza pneumonia (5). This protective effect correlated with the virus-specific cytotoxic activity of the transferred lymphocytes and is removed by treatment with anti-0 serum and complement. The experiments presented here indicate that spleen cells taken directly from mice undergoing a primary or secondary infection are less protective than immune spleen cells that are restimulated in vitro before transfer. This decreased ability to clear pulmonary virus and effect survival correlated with their relatively lower levels of influenza-specific cytotoxicity. Protection did not correlate with the level of natural killer cell activity of transferred cells. The results also indicate the immune spleen cells that are protective are influenza A subtype cross-reactive and are H-2-restricted; H-2d immune spleen cells effected recovery of H-2d but not H-2k challenged mice.

Animals↗
PubMed2000

A regulatory role for interleukin 4 in differential inflammatory responses in the lung following infection of mice primed with Th1- or Th2-inducing pertussis vaccines.

Protection against infectious pathogens at mucosal surfaces is dependent on local antibody responses, production of inflammatory mediators, and recruitment of immune effector cells to the site of infection. Since Th1 and Th2 cells produce cytokines with pro- and anti-inflammatory activities, immunization with vaccines that induce these T-cell subtypes may regulate the subsequent inflammatory response to infection. We have demonstrated that immunization of mice with pertussis whole-cell or acellular vaccines (Pw or Pa) selectively induces Th1 and Th2 cells, respectively. In this study we have used a murine respiratory-infection model to demonstrate that priming with a Th1- or Th2-inducing pertussis vaccine can influence the local inflammatory response and immune effector cells in the lung following aerosol challenge with Bordetella pertussis. Analysis of bronchoalveolar lavage (BAL) fluid taken during the course of B. pertussis infection of naïve mice or mice immunized with Pw revealed an early influx of neutrophils and local production of interleukin 1beta (IL-1beta) in the lungs. In contrast, neutrophil infiltration and IL-1beta production were not observed following challenge of mice immunized with the Th2-inducing Pa. Conversely, during infection local production of IL-6 and IL-1ra was significantly greater in mice immunized with Pa than in those immunized with Pw. Studies of knockout mice revealed neutrophil and lymphocyte infiltration in the lungs following B. pertussis infection of IL-4-defective (IL-4(-/-)) mice but not in wild-type mice immunized with Pa. Furthermore, the levels of IL-1beta, IL-6, and IL-1ra in Pa-immunized IL-4(-/-) mice were comparable to those in mice immunized with Pw. These results demonstrate distinct influences of Th1- and Th2-inducing vaccines on the protective inflammatory responses in the lungs following challenge with B. pertussis and implicate IL-4 as an important regulator of inflammatory-cell recruitment.

Animals↗
PubMed1997

Molecular aspects of cannabinoid receptors.

Two cannabinoid receptors are reviewed with regard to their primary structure, ligand-binding properties, and signal transduction systems. Both receptors have been cloned; therefore, the expression of their genes and the functional domains within the proteins can be examined. Binding of tritiated agonists has localized these receptors to the central nervous and immune systems. The CBI receptor is predominantly expressed in brain tissues and is found in both glial elements and neurons; subcellular localization to axons and terminals is evident. This receptor is found in motor, limbic, associative, cognitive, sensory, and autonomic brain structures. CBI receptors modulate the activities of calcium and potassium channels. The CB2 receptor is predominantly expressed in the immune system and is found in spleen, tonsils, thymus, mast cells, and blood cells. Although receptors appear to be involved in cannabimimetic-induced modulation of immune cell function, the receptor subtype that is principally involved in specific effects is difficult to determine because both receptors are often coexpressed in the same cells. Cannabimimetic-induced effects on mast cells and B cells appear, however, to be mediated by CB2 receptors.

Amino Acid Sequence↗
PubMed2006

Neuropeptide mimetics and antagonists in the treatment of inflammatory disease: focus on VIP and PACAP.

Corticosteroids are the mainstay treatment for most severe inflammatory disorders. Due to the considerable toxicity associated with their long-term use, there is a great need for alternative treatments. Recently, two closely related neuropeptides with potent neuromodulatory activities, vasoactive intestinal peptide (VIP) and pituitary adenylyl cyclase activating peptide (PACAP) have emerged as candidate molecules for the treatment of such pathologies. These peptides act primarily on three high affinity receptor subtypes expressed on multiple immune cell types, and orchestrate a cytokine response that is primarily anti-inflammatory. In this regard, systemic treatment with these peptides has been shown to greatly reduce the clinical symptoms and alter the pathogenic and cytokine profiles in animal models of rheumatoid arthritis, Crohn's disease, septic shock, and multiple sclerosis. Likewise, VIP and PACAP receptor knockout and overexpressing mice show altered immune responses in different models. We review here data demonstrating the potential effectiveness of these peptides in immune disorders, discuss receptor pharmacology and signaling pathways, describe the development of receptor specific agonists and antagonists, and discuss pharmaceutical considerations relevant to the specific delivery of analogs to the appropriate targets.

Animals↗