Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dendritic cells (DC) are key regulators of immune responses. Mature DC are traditionally considered to be immunogenic, although there is accumulating evidence that they can also be tolerogenic and induce Ag-specific regulatory T cells (Tregs). However, the mechanism of this Treg induction and the site of Treg action in vivo are yet to be defined. In this study, using the experimental model of interphotoreceptor retinoid-binding protein peptide (1-20)-induced experimental autoimmune uveoretinitis, we show that s.c. inoculation of IRBP-peptide-pulsed IL-10-producing LPS-activated mature DC (IL-10-DC) at one site (the cervical region) suppresses autoimmunity induced at a separate site (the inguinal region). Our data show that s.c. IL-10-DC correlates with an increase in the number of CD4(+)CD25(+)Foxp3(+) Tregs at the DC-draining lymph nodes (DC-dLN). However, although MHCII(-/-) IL-10-DC also induces Treg expansion at this DC-dLN, they failed to suppress experimental autoimmune uveoretinitis. Furthermore, unlike wild-type IL-10-DC, MHCII(-/-) IL-10-DC did not correlate with an increase in the percentage of Tregs expressing CD62L at the DC-dLN, nor did they associate with an increase in Treg number at a distal site. Similar effects were also observed after s.c. hen egg lysozyme-pulsed IL-10-DC, which produced a strong reduction in the number and activation of proliferating Ag-specific CD4(+) 3A9 T effector cells. We therefore propose that IL-10-DC require MHCII-dependent Ag presentation, and hence TCR ligation, to promote CD62L-mediated trafficking of Tregs to the site of T effector cell priming, where they suppress autoimmunity.
 ...
PMID:Lipopolysaccharide-activated IL-10-secreting dendritic cells suppress experimental autoimmune uveoretinitis by MHCII-dependent activation of CD62L-expressing regulatory T cells. 1832 97

We studied the effects of bactericidal proteins (lysozyme and lactoferrin) on endotoxin release from cell wall and inhibition of the growth of Escherichia coli colonies of different chemotypes. The structure of LPS core was found to be essential for the mechanisms of the interactions of the studied proteins with the cell wall. Cell viability after contact with cationic proteins is determined not by the amount of released LPS, but by the mechanism of damage to the cell wall.
 ...
PMID:Effect of chemotype on Escherichia coli interactions with bactericidal proteins. 1839 86

Cyclosporin A suppressed humoral immune response of Galleria mellonella larvae. Insects were immunized with LPS Pseudomonas aeruginosa and then injected with cyclosporin A. Immunosuppressive effects were expressed both, in larvae treated with cyclosporin A at the initial phase of immune response and at the effector phase of antibacterial immunity. Cyclosporin A moderately decreased lysozyme activity and significantly decreased antibacterial activity peptides against Escherichia coli. Immunosuppressive effects of cyclosporin A were observed after immunoblotting with antibodies anti-G. mellonella lysozyme. Tricine SDS/PAGE shown that synthesis of antibacterial peptides of larvae treated with cyclosporin A was considerably inhibited. Insects of impaired immune response by cyclosporin A action lost protective immunity to insect bacterial pathogen P. aeruginosa.
 ...
PMID:Immunosuppressive effect of cyclosporin A on insect humoral immune response. 1847 8

Since the role of striatal GABAergic medium-sized spiny (MSP) neurons in the modulation of the immune responses is largely unknown, we evaluated the humoral immune response in rats with bilateral lesion of the striatum caused by quinolinic acid, which destroys MSP neurons. Sham-operated rats and those with striatal lesions were immunized either with TNP-LPS, a T-independent antigen type 1, or one of several T-dependent antigens: ovoalbumin, bovine serum albumin, lysozyme, sheep red blood cells (SRBC) or outer membrane proteins (OMP) of Salmonella enterica serovar Typhimurium. The specific levels of serum IgM and IgG, as well as intestinal IgA antibodies were determined either by enzyme-linked immunosorbent assay (ELISA) or a haemagglutination assay 5 or 7 days after immunization. Our results show that the lesion of striatal MSP neurons attenuated the primary antibody response to the T-independent antigen type 1 (TNP-LPS), but increased the antibody response to T-dependent antigens (proteins, SRBC and OMP), indicating that the striatal neurons modulate the humoral immune response in rats. The mechanisms involved are probably related to a reduction in both the number of B cells and the expression of caveolin-1 in the spleen, as well as an increase in the number of CD4(+) T cells and in corticosterone levels of the serum.
 ...
PMID:Role of the striatum in the humoral immune response to thymus-independent and thymus-dependent antigens in rats. 1863 83

Lysozymes are key molecules of innate immunity and proved high bactericidal activity in fish, thus becoming attractive as tools for enhancing fish defences. In this study, a full-length c-type lysozyme cDNA from Senegalese sole (Solea senegalensis) has been cloned and characterized. The cDNA sequence was inferred from two overlapping fragments obtained by RACE-PCR and consisting on 631bp coding for 143 aminoacids. Catalytic and other conserved residues required for lysozyme activity were identified. Pair wise alignments showed the higher identities with c-type lysozyme from other flatfish. Expression patterns under various conditions showed a basal level and a clear upregulation mostly in hematopoietic organs after stimulation with LPS or infection with Photobacterium damselae. This study represents a first step on the genetics and function of the c-lysozyme of Senegalese sole, though disclosing g-DNA structure, allelic variability and antibacterial activity must be requirements prior its immunological properties might have biotechnological applications.
 ...
PMID:c-Lysozyme from Senegalese sole (Solea senegalensis): cDNA cloning and expression pattern. 1878 41

The effect of live bacteria (Micrococcus lysodeikticus and Vibrio anguillarum), and PAMPs (poly I:C, zymosan, LPS, LTA and CpG) on the production of intermediate toxic radicals (respiratory burst activity and production of nitric oxide) and mytilin B, myticin C and lysozyme gene expression was studied in vivo and in vitro. In vitro, bacteria were able to modulate the haemocytes' respiratory burst activity, being significantly increased after 6 h of incubation. The effect of pathogen-associated molecular patterns (PAMPs) was also studied. Zymosan produced an increase of the PMA-mediated response but an inhibition of the zymosan-mediated response. A significant increase of nitric oxide production was found at all the sampled time points (1, 3 and 6 h) in comparison with controls on both, the Gram-positive and Gram-negative bacteria. The in vivo responses measured on haemocytes after M. lysodeikticus injection were faster than those induced by V. anguillarum. However, V. anguillarum induced stronger in vitro effects. Mytilin B, myticin C and lysozyme in vitro gene expression, occurred at short times after infection. The maximum in vitro expression was detected 3 h post-infection. The differences between M. lysodeikticus and V. anguillarum in different measured parameters may suggest that different signalling pathways might be involved. Moreover, among all assayed PAMPs, LPS elicited the highest response.
 ...
PMID:Functional and molecular immune response of Mediterranean mussel (Mytilus galloprovincialis) haemocytes against pathogen-associated molecular patterns and bacteria. 1934 Sep 55

The effects of some pathogen-associated molecular patterns (PAMPs) (laminarin, LPS and poly I:C) on total hemocyte counts (THC), phenoloxidase (PO) activity, superoxide anion production and lectin, prophenoloxidase, lysozyme, cytosolic manganese superoxide dismutase (C-MnSOD) and catalase (CAT) gene expression were studied. The results showed that the production or activity of most tested immune factors and the expression of most tested genes were up-regulated after stimulation with PAMPs, among which the highest value of lectin with 4.4 times as much as that of the control group appeared at 6 h in hemocytes, of CAT with 47 times as much as that of the control group appeared at 12 h in hepatopancreas, and with 2.7 times higher than that of the control group at 24 h of C-MnSOD in hepatopancreas after laminarin injection. The peak value of proPO, lysozyme and C-MnSOD appeared at 6 h in hepatopancreas, 24 h in hepatopancreas and 24 h in hemocytes after LPS injection, respectively. The highest expression level of lysozyme appeared at 12 h in hemocytes after poly I:C injection. However, significant decreases of PO activity in hemocytes and lectin expression in hepatopancreas were found after poly I:C injection, and a dramatic down-regulation of proPO expression from 3 h to 48 h was found in hemocytes after injection with laminarin, LPS and poly I:C. The results suggest that the shrimp immune response could be activated or inhibited by different PAMPs, and that the hepatopancreas also plays a key role by synthesizing immune factors.
 ...
PMID:Immune response and gene expression in shrimp (Litopenaeus vannamei) hemocytes and hepatopancreas against some pathogen-associated molecular patterns. 1968 58

In order to determine time efficiency between the gel-based microchip (LabChip) and traditional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), glycoproteins and lipopolysaccharides were analyzed in this study. After 90 min of gel electrophoresis, glycoproteins (bovine serum albumin, lysozyme, ovalbumin, and apo-transferrin) and fluorescent lipopolysaccharides (LPS-O and LPS-S) under reducing conditions could be analyzed by SDS-PAGE, and it would take (including imaging and analyzing) more than 3 h. The same sample could also be assayed on a Bioanalyzer in combination with the LabChip, and it would only need 30 min from start to finish. The assay software automatically calculated the size and concentration of each separated peak and displayed the results in real time, thus eliminating time-consuming procedures such as imaging and analyzing. Compared to the traditional reducing SDS-PAGE, LabChip has a faster turnaround time.
 ...
PMID:Comparative studies on the analysis of glycoproteins and lipopolysaccharides by the gel-based microchip and SDS-PAGE. 1969 51

Synthesis and anti-inflammatory effects of certain furo[3',2':3,4]naphtho[1,2-d]imidazole derivatives 12-18 were studied. These compounds were synthesized from naphtho[1,2-b]furan-4,5-dione (10) which in turn was prepared from the known 2-hydroxy-1,4-naphthoquinone (7) in a one pot reaction. Furo[3',2':3,4]naphtho[1,2-d]imidazole (12) was inactive (IC(50) value of >30 microM) while its 5-phenyl derivative 13, with an IC(50) value of 16.3 and 11.4 microM against lysozyme and beta-glucuronidase release, respectively, was comparable to the positive trifluoperazine. The same potency was observed for 5-furan derivative 16 with an IC(50) value of 19.5 and 11.3 microM against lysozyme and beta-glucuronidase release, respectively. An electron-withdrawing NO(2) substituted on 5-phenyl or 5-furanyl group led to the devoid of activity as in the cases of 14 and 17. Among them, compound 15 exhibited significant inhibitory effects, with an IC(50) value of 7.4 and 5.0 microM against lysozyme and beta-glucuronidase release, respectively. For the LPS-induced NO production, the phenyl derivatives 12-15 were inactive while the nitrofuran counterparts 17 and 18 suppress LPS-induced NO production significantly, with an IC(50) value of 1.5 and 1.3 microM, respectively, which are more active than that of the positive 1400 W. Compounds 16-18 were capable of inhibiting LPS-induced iNOS protein expression at a dose-dependent manner in which compound 18, with an IC(50) of 0.52 microM in the inhibition of iNOS expression, is approximately fivefold more potent than that of the positive 1400 W. In the CLP rat animal model, compound 18 was found to be more active than the positive hydrocortisone in the inhibition of the iNOS mRNA expression in rat lung tissue. The sepsis-induced PGE2 production in rat serum decreased 150% by the pretreatment of 18 in a dose of 10 mg/kg.
 ...
PMID:Furo[3',2':3,4]naphtho[1,2-d]imidazole derivatives as potential inhibitors of inflammatory factors in sepsis. 1969 97

The accumulation of misfolded secreted IgM in the endoplasmic reticulum (ER) of X-box binding protein 1 (XBP-1)-deficient B cells has been held responsible for the inability of such cells to yield plasma cells, through the failure to mount a proper unfolded protein response. LPS-stimulated B cells incapable of secreting IgM still activate the XBP-1 axis normally, as follows: XBP-1 is turned on by cues that trigger differentiation and not in response to accumulation of unfolded IgM, but the impact of XBP-1 deficiency on glycoprotein folding and assembly has not been explored. The lack of XBP-1 compromised neither the formation of functional hen egg lysozyme-specific IgM nor the secretion of free kappa-chains. Although XBP-1 deficiency affects the synthesis of some ER chaperones, including protein disulfide isomerase, their steady state levels do not drop below the threshold required for proper assembly and maturation of the Igalpha/Igbeta heterodimer and MHC molecules. Intracellular transport and surface display of integral membrane proteins are unaffected by XBP-1 deficiency. Given the fact that we failed to observe any defects in folding of a variety of glycoproteins, we looked for other means to explain the requirement for XBP-1 in plasma cell development. We observed significantly reduced levels of phosphatidylcholine, sphingomyelin, and phosphatidylinositol in total membranes of XBP-1-deficient B cells, and reduced ER content. Terminal N-linked glycosylation of IgM and class I MHC was altered in these cells. XBP-1 hence has important roles beyond folding proteins in the ER.
 ...
PMID:XBP-1-deficient plasmablasts show normal protein folding but altered glycosylation and lipid synthesis. 1971 Apr 72


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>