Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009450 (infectious diseases)
 83,438 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytokines and the different glycosylation profiles of some acute phase proteins appear to be of great value in investigating the activity of inflammatory rheumatic diseases. Using an ELISA to measure the serum concentration of sIL-2R and IL-6 and an affinity electrophoresis with Concanavalin A as a lectin to determine the microheterogenity of the alpha-1-acid-glycoprotein (AGP), we tested the sera of 63 patients with various rheumatic and infectious diseases and 17 healthy persons and compared the results with the usual markers of inflammation, e.g. erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and with the clinical activity of the disease. ESR, CRP and sIL-2R were significantly elevated (p less than 0.001) in seropositive rheumatoid arthritis (RA) and in acute bacterial infection. ESR and CRP showed a better correlation with the clinical activity of RA than sIL-2R. Marked elevation of IL-6 was found only in 30% of RA patients in the early stage of the acute phase reaction (APR). The AGP reactivity coefficient (AGP-RC) was significantly decreased in RA (p less than 0.01) but increased in bacterial infections (p less than 0.001). Our results show that there is no advantage in measuring sIL-2R in the routine diagnosis of rheumatic diseases. Raised IL-6 levels seem to indicate an early stage of APR. If ESR and CRP are elevated, the AGP-RC helps to differentiate between infection and chronic inflammatory rheumatic diseases.
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PMID:[Interleukin-6 (IL-6), soluble interleukin-2-receptor (sIL-2R) and microheterogeneity of alpha-! acid glycoprotein (AGP): new markers of the acute-phase reaction?]. 153 25

The ability of a variety of epithelial, embryonal, placental, and neuronal cells to express the CD4 antigen and to be infected by human immunodeficiency virus 1 (HIV-1) was examined. Only two (IMR-32 and HeLa-T4) expressed CD4 detectable by indirect immunofluorescence, and both were infectable by HIV-1. Two others, a human laryngeal carcinoma (HEp-2) and human colonic carcinoma (HT-29), did not express CD4 antigen but were infectable by HIV-1. Infection of the HEp-2 cells was detectable four months (and 20 serial passages) later. Infection of HEp-2 cells was not inhibited by anti CD4 monoclonal antibody but was by the lectin concanavalin A. These results suggest the presence of a receptor other than CD4 can be involved in HIV-1 infection.
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PMID:Growth of human immunodeficiency virus I in cultured cells in the absence of the CD4 antigen. 180 30

Immunization with an inactivated whole-virus vaccine is highly effective in preventing lentivirus infection. The viral protein(s) essential to the induction of protective responses, however, have not been identified. To define the role of virion components in the induction of protective immunity, we evaluated the efficacy of glycoprotein-enriched and glycoprotein-depleted simian immunodeficiency virus (SIV) subunit vaccines prepared by lentil-lectin affinity chromatography of gradient-purified virions using the immunization and challenge regimen previously found successful with an inactivated whole-virus vaccine. Infection was determined by successful recovery of virus, the induction of SIV-specific antibody responses, and infection of naive recipients by inoculation with lymph-node-derived lymphocytes from the vaccinates. Immunization with the glycoprotein-enriched preparation prevented infection in two out of four monkeys, whereas the glycoprotein-depleted vaccine failed to prevent infection in all four vaccinates tested. However, the glycoprotein-depleted vaccine appeared to moderate the progression of SIV-induced disease compared with non-immunized infected control monkeys inoculated with the same challenge dose. These data suggest that subunit vaccines containing sufficient quantities of viral glycoproteins can protect against SIV infection, whereas subunit vaccines composed predominantly of viral core proteins cannot. The development of effective vaccines against HIV infection should include studies on the optimum presentation of the viral envelope glycoproteins to produce long-term broadly protective immune responses.
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PMID:Efficacy of SIV/deltaB670 glycoprotein-enriched and glycoprotein-depleted subunit vaccines in protecting against infection and disease in rhesus monkeys. 188 40

Infection with Schistosoma mansoni is initiated by penetration of the intact skin of the mammalian host with the head but not the tail of the parasite cercariae. The surface of cercariae is covered by a 1-2-micron thick carbohydrate-rich glycocalyx (gx). Furthermore, the transformation of cercariae to schistosomula (the next parasitic stage in the mammalian host) is associated with loss of gx from the bodies. To understand the role of gx in the host-parasite relationship, we have characterized the gx of both bodies and tails of S. mansoni cercariae. A fluorescent fucose-specific lectin-stained bodies and not tails of the organism. Moreover, when an enriched preparation of gx obtained by extraction with 40% aqueous phenol and exclusion from Sepharose CL-6B was subjected to affinity chromatography on insolubilized Lotus lectin, which binds fucose-containing glycans, only body gx was retained. Body gx is smaller and less negatively charged than tail gx. Electron microscopy showed that gx from bodies and tails is composed of 25-40-nm particles and fibrillar material. Carbohydrate composition of gx of bodies and tails indicate that fucose and glucose are major components, respectively. beta-Elimination experiments indicate that the linkage sugar is N-acetylgalactosamine in both cases. Upon treatment with alkaline borohydride, nearly 90% of gx of both bodies and tails was recovered as two glycan chains: I and II (Mr approximately 10,500 and 5,600, respectively). Glycan I was in both cases more negatively charged than glycan II. Fucose is the predominant sugar in glycan I of the bodies while glycan I of tails is mainly composed of glucose. The gx was resistant to several proteases. This resistance and the abundance of carbohydrate in gx may be of biological importance for survival of cercariae. The substantial differences observed between the gx of bodies and tails may provide the basis for understanding the mechanism of selective release of body gx during transformation.
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PMID:Glycocalyx of bodies versus tails of Schistosoma mansoni cercariae. Lectin-binding, size, charge, and electron microscopic characterization. 198 52

Two strains of Staphylococcus saprophyticus with well characterized cell surface structures were studied to determine the contribution of lectinophagocytosis versus opsonophagocytosis exerted by human phagocytic cells from five healthy donors. The luminol specific chemiluminescence assay was used to evaluate the response of phagocytes. Human polymorphonuclear leukocytes (PMNL) were demonstrated to have surface lectin receptors, since the chemiluminescence response towards both S. saprophyticus strains was inhibited by lectin-specific glycoconjugates for those organisms. Phagocytosis of S. saprophyticus by mononuclear cells was not inhibited by microbial lectin-specific glycoconjugates but was inhibited by D-mannose, suggesting that human monocytes express D-mannose specific lectins on their surface.
Infection
PMID:Chemiluminescence response of human polymorphonuclear and mononuclear phagocytic cells induced by Staphylococcus saprophyticus, lectinophagocytosis versus opsonophagocytosis. 231 75

BALB/c mice immunized by intraperitoneal injection of purified Pseudomonas aeruginosa lectin preparations are fully protected against a lethal dose of the live bacteria. Intraperitoneal inoculation of splenocytes or bone marrow cells obtained from actively immunized mice into naive syngeneic mice was shown to significantly increase their resistance to P. aeruginosa infection. A similar transfer of splenocytes or bone marrow cells from untreated control mice did not provide protection against a lethal Pseudomonas challenge. Administration of immunocompetent cells from immunized animals to naive mice by the i.v. route was less efficient than the i.p. inoculation, probably due to different homing of the cells. Only the i.p. injection concentrated the immune cells to the site of infection.
Infection
PMID:Adoptive transfer of resistance to Pseudomonas aeruginosa infection by splenocytes and bone marrow cells from BALB/c mice immunized by Pseudomonas aeruginosa lectin preparations. 261 34

Numerous bacterial strains produce surface lectins, commonly in the form of fimbriae that are filamentous assemblies of protein subunits. Among the best characterized of these are the type 1 (mannose specific) fimbrial lectins of Escherichia coli that consist almost exclusively of one class of subunit with a molecular mass of 17 kDa. They possess an extended combining site corresponding to a trisaccharide and preferentially bind carbohydrate units of oligomannose or hybrid type. Type 1 fimbriae also possess a hydrophobic region close to the carbohydrate-binding site, since aromatic alpha-mannosides inhibit strongly (up to 1000-times more than methyl alpha-mannoside) the agglutination of yeasts by the bacteria and the adherence of the latter to pig ileal epithelial cells. The combining sites of type 1 fimbriae of the salmonellae and of other enteric bacteria are different from those of E. coli in that they are smaller and do not possess a hydrophobic region. The various bacterial surface lectins appear to function primarily in the initiation of infection by mediating bacterial adherence to epithelial cells, e.g. in the urinary and gastrointestinal tracts. The mannose specific lectins also act as recognition molecules in lectinophagocytosis (i.e. phagocytosis of the bacteria in the absence of opsonins) by mouse, rat and human peritoneal macrophages, and human polymorphonuclear leukocytes. Affinity chromatography of membrane lysates from human polymorphonuclear leukocytes on immobilized type 1 fimbrial lectin, using methyl alpha-mannoside as eluent, showed that glycoproteins with apparent molecular masses of 70-80, 100 and 150 kDa act as receptors for the bacteria. Inhibition experiments with monoclonal antibodies suggest that the glycoprotein bands of 100 and 150 kDa may be identical with the alpha and beta subunits of leukocyte complement receptors and adhesion glycoproteins involved in complement-mediated opsonophagocytosis. The systems described serve as a fine illustration for the biological role of lectin-carbohydrate interactions. Further studies of these systems will lead to a deeper understanding of the molecular basis of infectious diseases, and perhaps also to new approaches for their prevention.
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PMID:Bacterial lectins, cell-cell recognition and infectious disease. 288 20

Patients with the acquired immune deficiency syndrome (AIDS) and AIDS-related conditions are known to have abnormalities of T cell subpopulations, including a decreased helper/inducer (bearing the CD4 antigen) to suppressor/cytotoxic (bearing the CD8 antigen) T cell ratio and decreased absolute numbers of T cells with the CD4+ phenotype. Infection of T cells with a retrovirus, termed human immunodeficiency virus (HIV), is thought to be important in these abnormalities. HIV infection alone does not adequately explain the CD4+ T-cell abnormalities seen in AIDS, however, and the nature of T-cell destruction in this disease remains poorly characterized. Here we describe an AIDS-related serum autoantibody that reacts with an antigen of relative molecular mass 18,000 (Mr 18K) restricted to lectin-stimulated or HIV-infected CD4+ T cells. The antibody also suppresses proliferation of CD4+ T cells in vitro and induces cytotoxicity of these cells in the presence of complement. Its role in the development of AIDS merits attention.
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PMID:An AIDS-related cytotoxic autoantibody reacts with a specific antigen on stimulated CD4+ T cells. 295 26

In vitro and in vivo experiments with Balb/c mice and Pseudomonas aeruginosa ATCC 27853 supported our hypothesis that bacterial lectins play an important role in the organotropy of infectious diseases. In vitro and in vivo adhesion of P. aeruginosa was mediated by N-acetylneuraminic acid (NANA) receptors. Blocking of the binding sites (lectins) on the bacterial surfaces with competitive specific carbohydrates (NANA) completely prevented the bacterial adhesion process in vitro. In vivo the number of adherent organisms in various organs decreased dramatically in the presence of NANA, whereas non-related carbohydrates (e.g. D-galactose) just showed negligible effects. Additionally, the application of NANA-treated organisms protected the animals from septicemia and death. Therefore, blocking of bacterial lectin receptors with specific carbohydrates might be of clinical relevance to prevent bacterial attachment to organ cells.
Infection
PMID:In vitro and in vivo inhibition of lectin mediated adhesion of Pseudomonas aeruginosa by receptor blocking carbohydrates. 311 98

The potency of the polyvalent bacterial vaccine (Infectvac) to prevent lethal infections with S. pneumoniae ATCC 6301 was examined. NMRI-mice were protected 2-5 times better than untreated controls. The protection is based on activation of resistance-mechanisms, e.g. interferon production. Most interesting is a strong activation of the phagocytosis-killing-system of alveolar macrophages after oral application of antigen (information: gut mucosa to lung mucosa). Using the same infection model the important role of bacterial lectins for infectious diseases was demonstrated. Blocking the combining site of the bacterial lectin of S. pneumoniae by intranasal application of N-acetylglucosamine (the specific carbohydrate for the lectin) was able to prevent a lethal infection with S. pneumoniae 3-times better than PBS or using not lectin relevant carbohydrates. Therefore, blocking the lectin receptor with specific carbohydrates might also be of clinical relevance to prevent acute respiratory infections (ARI).
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PMID:Lectins and their role in a new polyvalent bacterial vaccine against ARI. 322 36


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