OBJECTIVETo study the mechanism of prophylactic effects of nasal tolerance with a dual analogue (Lys262-Ala207) on experimental autoimmune myasthenia gravis (EAMG).

METHODSClinical and immunological changes were observed in Lewis rats administered with dual analogue Lys262-Ala207 nasally, to compare the effects between the rats with predetermined dosage of Lys262-Ala207 and control peptides at two different time points, before the day (Group A or C) or on the day (Group B or D) of immunization with acetylcholine receptor (AChR) in complete Freud's adjuvant for 10 consecutive days. The clinical scores was evaluated for 50 days post immunization. Numbers of MNC expressing IFN-gamma, IL-4 or IL-10 and CD4+ and/or CD25+ from lymph nodes were enumerated by flow cytometry. Proliferative response, expressed as stimulation index (SI), was suppressed in response to antigen-specific stimulation in the rats receiving dual analogue, as compared with the rats receiving saline buffer only.

RESULTSGroup A and group B of Lewis rats developed EAMG with reduced severity, as compared to the control groups. Number of cells synthesizing IFN-gamma, IL-4 or IL-10 decreased, whereas numbers of CD4+CD25+ cells increased in group A and B than those in the control groups. Proliferative response was suppressed in response to antigen-specific stimulations in the rats receiving dual analogue Lys262-Ala207.

CONCLUSIONSNasal administration with a dual analogue Lys262-Ala207 at two different time points, before the day and on the day of immunization, could delay symptoms of muscular weakness in EAMG rats, which was associated with suppression of immune function in AChR antigen-specific T cells and lay a scientific foundation for treatment of human MG with nasal dual analogue.

Administration, Intranasal ; Animals ; Antibody Affinity ; Autoantibodies ; immunology ; Dose-Response Relationship, Immunologic ; Female ; Immune Tolerance ; drug effects ; Immunity, Cellular ; Immunity, Mucosal ; Lymphocyte Activation ; Myasthenia Gravis ; immunology ; prevention & control ; Nasal Mucosa ; immunology ; Rats ; Rats, Inbred Lew

OBJECTIVETo observe the effects of astragalus polysaccharide (AP) on the intestinal mucosal morphology, level of secretory IgA (s-IgA) in intestinal mucus, and distribution of T lymphocyte subsets in Peyer's patch in rats with severe scald injury.

METHODSOne hundred and thirty SD rats were divided into sham injury group (SI, sham injured, n = 10), scald group (S, n = 30), low dosage group (LD, n = 30), moderate dosage group (MD, n = 30), and high dosage group (HD, n = 30) according to the random number table. Rats in the latter 4 groups were inflicted with 30% TBSA full-thickness scald on the back. From post injury hour 2, rats in groups LD, MD, and HD were intraperitoneally injected with 0.5 mL AP solution with the dosage of 100, 200, and 300 mg/kg each day respectively, and rats in group S were injected with 0.5 mL normal saline instead. Ten rats from group SI immediately after injury and 10 rats from each of the latter 4 groups on post injury day (PID) 3, 7, 14 were sacrificed, and their intestines were harvested. The morphology of ileal mucosa was examined after HE staining; the level of s-IgA in ileal mucus was determined with double-antibody sandwich ELISA method; the proportions of CD3⁺, CD4⁺, CD8⁺ T lymphocytes in Peyer's patches of intestine were determined with flow cytometer, and the proportion of CD4⁺ to CD8⁺ was calculated. Data were processed with one-way analysis of variance, analysis of variance of factorial design, and SNK test.

RESULTS(1) Villi in normal form and intact villus epithelial cells were observed in rats of group SI immediately after injury, while edema of villi and necrosis and desquamation of an enormous amount of villi were observed in groups with scalded rats on PID 3, with significant infiltration of inflammatory cells. On PID 7, no obvious improvement in intestinal mucosal lesion was observed in groups with scalded rats. On PID 14, the pathology in intestinal mucosa of rats remained nearly the same in group S, and it was alleviated obviously in groups LD and MD, and the morphology of intestinal mucosa of rats in group HD was recovered to that of group SI. (2) On PID 3, 7, and 14, the level of s-IgA in intestinal mucus significantly decreased in groups S, LD, MD, and HD [(43 ± 5), (45 ± 5), (46 ± 5) µg/mL; (47 ± 5), (48 ± 5), (49 ± 6) µg/mL; (50 ± 6), (51 ± 5), (52 ± 5) µg/mL; (53 ± 6), (54 ± 5), (55 ± 5) µg/mL] as compared with that of rats in group SI immediately after injury [(69 ± 4) µg/mL, with P values below 0.05]. The level of s-IgA in intestinal mucus of rats in group MD was significantly higher than that in group S at each time point (with P values below 0.05), and that of group HD was significantly higher than that in groups S and LD at each time point (with P values below 0.05). (3) Compared with those of rats in group SI immediately after injury, the proportions of CD3⁺ T lymphocytes and CD4⁺ T lymphocytes significantly decreased in groups with scalded rats at each time point (with P values below 0.05), except for those in group HD on PID 14. The proportion of CD4⁺ T lymphocytes of rats in group LD was significantly higher than that in group S on PID 3 (P < 0.05). The proportions of CD3⁺ T lymphocytes and CD4⁺ T lymphocytes were significantly higher in groups MD and HD than in groups S and LD (except for the proportion of CD4⁺ T lymphocytes in group MD on PID 3 and 14) at each time point (with P values below 0.05). The proportion of CD3⁺ T lymphocytes on PID 7 and 14 and that of CD4⁺ T lymphocytes on PID 3 were significantly higher in group HD than in group MD (with P values below 0.05). Compared with that of rats in group SI immediately after injury, the proportion of CD8⁺ T lymphocytes significantly increased in the other 4 groups at each time point (with P values below 0.05). The proportion of CD8⁺ T lymphocytes was significantly lower in rats of group LD on PID 7 and 14 and groups MD and HD at each time point than in group S (with P values below 0.05). The proportion of CD8⁺ T lymphocytes was significantly lower in rats of group MD on PID 7 and 14 and group HD at each time point than in group LD (with P values below 0.05). The proportion of CD8⁺ T lymphocytes was significantly lower in rats of group HD on PID 7 and 14 than in group MD (with P values below 0.05). On PID 3, 7, and 14, the proportion of CD4⁺ to CD8⁺ was significantly lower in groups S, LD, MD, and HD (0.65 ± 0.11, 0.68 ± 0.13, 0.73 ± 0.22; 0.76 ± 0.15, 0.78 ± 0.14, 0.90 ± 0.10; 0.85 ± 0.21, 0.89 ± 0.18, 1.08 ± 0.19; 0.99 ± 0.20, 1.05 ± 0.21, 1.25 ± 0.23) as compared with that of rats in group SI immediately after injury (1.74 ± 0.20, with P values below 0.05). The proportion of CD4⁺ to CD8⁺ was significantly higher in rats of group HD than in group MD on PID 7 (P < 0.05), and the proportion was significantly higher in these two groups than in group S at each time point (with P values below 0.05). The proportion of CD4⁺ to CD8⁺ was significantly higher in rats of group MD on PID 14 and group HD at each time point than in group LD (with P values below 0.05). Compared within each group, the proportions of CD3⁺, CD4⁺, CD8⁺ T lymphocytes and the proportion of CD4⁺ to CD8⁺ of rats in groups LD, MD, and HD showed a trend of gradual elevation along with passage of time.

CONCLUSIONSAP can improve the injury to intestinal mucosa and modulate the balance of T lymphocyte subsets in Peyer's patch in a time- and dose-dependent manner, and it can promote s-IgA secretion of intestinal mucosa in a dose-dependent manner.

Animals ; Astragalus Plant ; adverse effects ; Burns ; immunology ; pathology ; physiopathology ; Dose-Response Relationship, Drug ; Immunity, Mucosal ; Immunoglobulin A ; metabolism ; Intestinal Mucosa ; metabolism ; physiology ; Intestine, Small ; metabolism ; Peyer's Patches ; immunology ; physiopathology ; Polysaccharides ; Rats ; Rats, Sprague-Dawley ; Soft Tissue Injuries ; T-Lymphocyte Subsets ; immunology

A previous report by this laboratory demonstrated that bacterial iron chelator (siderophore) triggers inflammatory signals, including the production of CXC chemokine IL-8, in human intestinal epithelial cells (IECs). Microarray-based gene expression profiling revealed that iron chelator also induces macrophage inflammatory protein 3 alpha (MIP-3alpha)/ CC chemokine-ligand 20 (CCL20). As CCL20 is chemotactic for the cells involved in host adaptive immunity, this suggests that iron chelator may stimulate IECs to have the capacity to link mucosal innate and adaptive immunity. The basal medium from iron chelator deferoxamine (DFO)-treated HT-29 monolayers was as chemotactic as recombinant human CCL20 at equivalent concentrations to attract CCR6+ cells. The increase of CCL20 protein secretion appeared to correspond to that of CCL20 mRNA levels, as determined by real-time quantitative RT-PCR. The efficacy of DFO at inducing CCL20 mRNA was also observed in human PBMCs and in THP-1 cells, but not in human umbilical vein endothelial cells. Interestingly, unlike other proinflammatory cytokines, such as TNF-alpha and IL-1beta, a time-dependent experiment revealed that DFO slowly induces CCL20, suggesting a novel mechanism of action. A pharmacologic study also revealed that multiple signaling pathways are differentially involved in CCL20 production by DFO, while some of those pathways are not involved in TNF-alpha-induced CCL20 production. Collectively, these results demonstrate that, in addition to some bacterial products known to induce host adaptive immune responses, direct chelation of host iron by infected bacteria may also contribute to the initiation of host adaptive immunity in the intestinal mucosa.
Calcium/metabolism ; Cell Movement/drug effects ; Chemokines, CC/genetics/*metabolism ; Deferoxamine/*pharmacology ; Egtazic Acid/analogs & derivatives/pharmacology ; HT29 Cells ; Humans ; Immunity, Mucosal/*drug effects ; Intestinal Mucosa/*drug effects/immunology/metabolism ; Iron Chelating Agents/*pharmacology ; Macrophage Inflammatory Proteins/genetics/*metabolism ; NF-kappa B/metabolism ; Phosphoprotein Phosphatase/physiology ; Protein Transport/drug effects ; Protein-Serine-Threonine Kinases/physiology ; RNA, Messenger/genetics/metabolism ; Receptors, Chemokine/metabolism ; Research Support, Non-U.S. Gov't

OBJECTIVETo explore the effects of Huoxiang Zhengqi liquid (HXZQ) on enteric mucosal immune responses in mice with Bacillus dysenteriae and Salmonella typhimurium induced diarrhea (BSD).

METHODMice were randomly divided into four groups with 10 mice in each group: control group (control), BSD group, Huoxiang Zhengqi liquid treated BSD groups at high dosage and low dosage (HXZQ high, HXZQ low). HXZQ was administrated from the day of diarrhea induction at dosage of 5.21 g kg(-1) and 0.52 g kg (-1) respectively. Peyer's patch and periphery lymphocytes were prepared for flow cytometry, and level of TNF-alpha in periphery and enteric tissue homogenate were determined with ELISA. Student's t-test was used for statistics.

RESULTMice in BSD group started showing continuous diarrhea at the day of induction till the fourth day when the mice were sacrificed. Diarrhea in the mice of HXZQ high and low groups lasted for 36 and 54 h respectively. There were more CD4+ and CD8+ cells in periphery, less CD4+ cells in peyer's patch in BSD mice comparing to normal mice. In peyer's patch, there were more CD8+ cells in mice in HXZQ high and low groups and more CD4+ in mice in HXZQ high group. Higher level TNF-alpha in periphery and intestinal tissue homogenate in BSD group were observed. Mice in HXZQ high group showed the decreased level TNF-alpha in periphery and enteric tissue homogenate.

CONCLUSIONThe immune regulation on peyer's patch CD4+ and CD8+ cells and suppression on TNF-alpha level in enteric homogenate might partially explain the effect of HXZQ on improvement of BSD.

Animals ; CD4-CD8 Ratio ; Colon ; immunology ; metabolism ; pathology ; Diarrhea ; immunology ; metabolism ; microbiology ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacology ; Dysentery, Bacillary ; immunology ; metabolism ; microbiology ; Immunity, Mucosal ; drug effects ; Intestinal Mucosa ; immunology ; pathology ; Male ; Mice ; Mice, Inbred BALB C ; Peyer's Patches ; drug effects ; immunology ; pathology ; Plants, Medicinal ; chemistry ; Random Allocation ; Salmonella Infections ; immunology ; metabolism ; microbiology ; Salmonella typhimurium ; immunology ; Shigella dysenteriae ; immunology ; T-Lymphocyte Subsets ; drug effects ; immunology ; pathology ; Tumor Necrosis Factor-alpha ; blood ; metabolism

Cholera toxin, which has been frequently used as mucosal adjuvant, leads to an irreversible activation of adenylyl cyclase, thereby accumulating cAMP in target cells. Here, it was assumed that beta2-adrenergic agonist salbutamol may have modulatory functions of immunity induced by DNA vaccine, since beta2-adrenergic agonists induce a temporary cAMP accumulation. To test this assumption, the present study evaluated the modulatory functions of salbutamol co-administered with DNA vaccine expressing gB of herpes simplex virus (HSV) via intranasal (i.n.) route. We found that the i.n. co-administration of salbutamol enhanced gB-specific IgG and IgA responses in both systemic and mucosal tissues, but optimal dosages of co-administered salbutamol were required to induce maximal immune responses. Moreover, the mucosal co-delivery of salbutamol with HSV DNA vaccine induced Th2-biased immunity against HSV antigen, as evidenced by IgG isotypes and Th1/Th2-type cytokine production. The enhanced immune responses caused by co-administration of salbutamol provided effective and rapid responses to HSV mucosal challenge, thereby conferring prolonged survival and reduced inflammation against viral infection. Therefore, these results suggest that salbutamol may be an attractive adjuvant for mucosal genetic transfer of DNA vaccine.
Adjuvants, Immunologic/*pharmacology ; Adrenergic beta-Agonists/immunology/*pharmacology ; Albuterol/immunology/*pharmacology ; Animals ; Antibodies, Viral/immunology ; Cercopithecus aethiops ; Cytokines/immunology ; Dose-Response Relationship, Drug ; Dose-Response Relationship, Immunologic ; Herpes Simplex/immunology/*prevention & control ; Herpes Simplex Virus Vaccines ; Immunity, Mucosal/*drug effects/immunology ; Immunoglobulin A/immunology ; Immunoglobulin G/immunology ; Mice ; Simplexvirus/*immunology ; Th1 Cells/immunology ; Th2 Cells/immunology ; Vaccines, DNA/*immunology/pharmacology ; Vero Cells ; Viral Envelope Proteins/immunology