CONICET | Buscador de Institutos y Recursos Humanos

Congreso; 15th Latin American Symposium on Biotechnology, Biomedical, Biopharmaceutical and Industrial Applications of Capillary Electrophoresis and Microchip Technology; 2009

Resumen:

&amp;amp;amp;lt;!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-1610611985 1107304683 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES-AR;} .MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:10.0pt; mso-ansi-font-size:10.0pt; mso-bidi-font-size:10.0pt;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} /* List Definitions */ @list l0 {mso-list-id:1485973092; mso-list-type:hybrid; mso-list-template-ids:1296487034 1254105766 67764249 67764251 67764239 67764249 67764251 67764239 67764249 67764251;} @list l0:level1 {mso-level-tab-stop:36.0pt; mso-level-number-position:left; text-indent:-18.0pt; mso-ansi-font-size:12.0pt; mso-bidi-font-size:12.0pt; font-family:"Times New Roman","serif"; mso-ansi-font-weight:normal; mso-ansi-font-style:normal;} ol {margin-bottom:0cm;} ul {margin-bottom:0cm;} --&amp;amp;amp;gt;  The presence of LPS was examined in homogenates of joint obtained from Yersinia-infected TNFRp55-/- and WT mice by capillary electrochromatography (CEC) using multi-walled nanotubes (MWNTs) as a pseudostationary phase (PSP). The LPS from Y. enterocolitica O:3 was extracted by hot phenol-water method, as described previously [1], and used as standard. For PSP-CEC, we used a Beckman P/ACE MDQ instrument (Beckman Instruments, Inc. Fullerton, CA) equipped with a diode array detector and a data handling system comprising an IBM personal computer and P/ACE System MDQ Software. The fused-silica capillaries had the following dimensions: 57 cm total length, 50 cm effective length, 75 μm id, 375 μm od. The detection was performed at 197 nm; the capillary temperature was maintained at 18°C, the voltage was set at 25 kV. Samples were pressure-injected at the cathodic side at 0.5 psi for 10 seconds. The background electrolyte (BGE) used consisted of phosphate buffer 20 mM plus 0.004% of MWNTs with pH 8.0. In this work we probed a several concentrations of nanotubes in BGE. We have the best separation at 0.004%, further increase of the nanoparticles concentration does not lead to further enhancement of the separation. We suppose that the presence of MWNTs decreased analytecapillary wall interactions and stacked the proteins into narrower zones, due to their large surface area and the negative charge of their surface on the surface. In view of the fact that reactive arthritis (ReA) is an aseptic synovitis [2] and none bacteria were found in the joint of arthritic mice, we investigated the presence of LPS in the joint using PSP-CEC, a high-resolution separation technique. We detected Yersinia LPS at day 14 after infection in joints of WT and TNFRp55-/- mice, with higher peak, suggesting more concentration, in knockout mice. This was in accord with impaired bacterial clearance that we detected previously in this group of mice [3]. As a conclusion we could infer that bacterial antigens may trigger acute joint inflammation.