Even though the brain has been considered to be an immunologically privileged organ, recent reports showed that certain cells of the brain may be involved in immunological process in the brain. For example, some cells of the brain can present antigen to T-lymphocytes, to express class II major histocompativility antigen, and secrete interleukin-1 and -3 molecules. In addition, they are capable to phagocytose particles and possess receptors for the Fc portion on IgG. In this study, the authors tried to isolate the microglial cells from new born mice and characterize them. The isolated cells could produce such reactive oxygen intermediates(ROIs) an superoxide and hydrogen peroxide that were measured by luminometer after amplification by lucigenin and luminol respectively and could secrete reactive nitrogen intermediates(RNIs), when the cells were incubated with r-IFN plus LPS. The cells could also ingest fluorescent particles and raise intracellular calcium after stimulation with agonists when measured by flow cytometer. Our data showed that the microglial cells of the brain may belong to a member of mononuclear phagocytic system(MPS) of the body that are responsible for the host defence against invading microorganisms.
Animals ; Brain ; Calcium ; Hydrogen Peroxide ; Immunoglobulin G ; Interleukin-1 ; Luminol ; Mice ; Nitrogen ; Oxygen ; Superoxides ; T-Lymphocytes

AIMTo establish a simple and novel method for the determination of vitamin B2 rapidly in pharmaceutical preparations.

METHODSVitamin B2 was determined by a chemiluminescence (CL) sensor combined with flow-injection (FI) technology. The analytical reagents involved in the CL reaction, luminol and hexacyanoferrate (III), were both immobilized on an anion-exchange resin column in FI system. The CL signal produced by the reaction between luminol and hexacyanoferrate (III), which were eluted from the column through sodium phosphate injection, decreased in the presence of vitamin B2.

RESULTSThe decreased CL intensity was linearly correlated with the vitamin B2 concentration in the range of 0.01-1.0 microgram.mL-1, the detection limit was 4.0 ng.mL-1 vitamin B2 (3 sigma). At a flow rate of 2.0 mL.min-1, the procedure including sampling and washing could be performed in 2 min with a relative standard deviation of less than 3.0%.

CONCLUSIONThe flow sensor exhibited both good sensitivity and stability. It could be reused more than 450 times and has been applied successfully to the analysis of vitamin B2 in pharmaceutical preparations.

Flow Injection Analysis ; methods ; Luminescent Measurements ; Luminol ; Riboflavin ; analysis ; Tablets ; chemistry

AIMTo establish a new and simple flow injection method for the rapid determination of acetylspiramycin (ASPM).

METHODSASPM was determined by chemiluminescence (CL) method combined with flow injection (FI) technology, which was based on the inhibitive effect of ASPM on the chemiluminescence reaction of the luminol-K3Fe (CN)6 system.

RESULTSThe decrease of chemiluminescence intensity was proportional to the logarithm of ASPM concentration (0.1-100) microgram.L-1, the detection limit was 40 ng.L-1 (3 sigma). The whole process, including sampling and washing, could be completed in 0.5 min with a RSD less than 3.0% (n = 5).

CONCLUSIONThe FI-CL method is of both high sensitivity and good selectivity giving a throughput of 120 h-1. The proposed method was applied successfully to the determination of ASPM in pharmaceutical preparations and human urine without any pre-treatment. It was found that the ASPM concentration reached its maximum after being orally administrated for two hours.

Anti-Bacterial Agents ; analysis ; blood ; urine ; Flow Injection Analysis ; Humans ; Luminescent Measurements ; Luminol ; chemistry ; Male ; Microchemistry ; Spiramycin ; analogs & derivatives ; analysis ; blood ; urine

PURPOSE: HL-60 is a promyelocytic cell line. Fc receptors and complement receptor 3 (CR3) play important role in the protective response of granulocytes and monocytes against microbial infection. We quantified the expression of Fc I, Fc II, Fc III, and CD11b/CD18 during differentiation using HL-60 cells by N-N-dimethylformamide (DMF). Functional studies, such as phagocytic activity, respiratory burst and ADCC, were also performed. METHODS: HL-60 cells were induced to differentiate by adding 0.8% DMF. On the 4th and 7th day after stimulation as well as before stimulation, the cells were analyzed for phenotypic and functional differentiaton. Phenotypic analysis was performed by flow cytometry after staining the cells with PE-conjugated anti-human CD64, CD32, CD16, CD11b, CD18, and isotype controls. And the measured fluorescent intensity was transformed into Molecules of Equivalent Soluble Fluorochromes (MESF). Phagocytic activity was also measured by flow cytometry after incubation with fluorochrome-conjugated beads. Respiratory burst was measured by chemiluminescence assay of cells incubated with luminol after stimulation with PMA. ADCC was measured by hemoglobin release assay. RESULTS: The expression of CD11b, CD18 and CD64 on HL-60 cells markedly increased on the 4th day and slightly decreased on the 7th day. Expression of CD32 was already induced before differentiation induction and slightly increased by DMF. CD16 was not expressed during differentiation. In phagocytic assay, the phagocytic cell fraction increased by stimulation on 4th and 7th day. Chemiluminescence showed the DMF increased the respiratory burst of HL-60 cells on the 4th and 7th day. In ADCC, DMF increased the target cell lysis continuously. CONCLUSION: HL-60 cells which were differentiated with DMF for are good models for studying opsonophagocytic assay of immunized sera.
Antibody-Dependent Cell Cytotoxicity ; Cell Line* ; Flow Cytometry ; Fluorescent Dyes ; Granulocytes ; HL-60 Cells ; Humans ; Luminescence ; Luminol ; Monocytes ; Phagocytes ; Receptors, Complement ; Receptors, Fc ; Respiratory Burst