Gobierno universitario : entre la autogestión estamental y la responsabilidad social

<p>Low doses of the relatively neutralization resistant SHIV _SF162P3 isolate were incubated at 37⁰C for four hours with concentrations of the human monoclonal antibody IgG1 b12. The mixture was then added to GHOST cells and allowed to absorb for 24 hours. The cells were washed and cultured for a further 24 hours (4/24/2 assays). Four duplicate cultures were used for each point within a replicate. Data are fitted to a second-order (quadratic) equation. Dotted lines are extrapolations to the horizontal axis calculated from the quadratic plots. Axes are truncated and some symbols are excluded to improve clarity, especially around the origin. <b>A</b>. SHIV_SF162P3 exposed to GHOST cells from passage 7 (1 replicate) and 9 (2 replicates). Gray: control cultures where virus were incubated without monoclonal antibody: y = -0.00285 x² + 1.310 x -6.009; green: Virus pre-incubated with 0.625 µg/ml IgG1 b12: y = -0.00284 x² + 0.939 x -0.517. <b>B</b>. Gray same as for A. blue: Virus pre-incubated with 0.25 µg/ml IgG1 b12: y = -0.000606 x² + 0.870 x + 3.152. <b>C</b>. SHIV_SF162P3 exposed to GHOST cells from passages 15, 17 and 21. Gray: control cultures where virus were incubated without monoclonal antibody: y = 0.00182 x² + 0.665 x + 11.01; green: Virus pre-incubated with 0.625 µg/ml IgG1 b12: y = + 0.00135 x² + 0.487 x + 8.334. <b>D</b>. Gray same as for C. blue: where cultures are exposed to virus pre-incubated with 0.25 µg/ml IgG1 b12: y = 0.00140x² + 0.616x + 5.768. Interval between points where control and 0.25 µg/ml IgG1 b12 plots cut x-axis: 7.81 infectious virus.</p

<i>In Vitro</i> Neutralization of Low Dose Inocula at Physiological Concentrations of a Monoclonal Antibody Which Protects Macaques against SHIV Challenge

<div><p>Background</p><p>Passive transfer of antibodies can be protective in the simian human immunodeficiency virus (SHIV) – rhesus macaque challenge model. The human monoclonal antibody IgG1 b12 neutralizes human immunodeficiency type 1 (HIV-1) <i>in vitro</i> and protects against challenge by SHIV. Our hypothesis is that neutralizing antibodies can only completely inactivate a relatively small number of infectious virus.</p> <p>Methods And Findings</p><p>We have used GHOST cell assays to quantify individual infectious events with HIV-1_SF162 and its SHIV derivatives: the relatively neutralization sensitive SHIV_SF162P4 isolate and the more resistant SHIV_SF162P3. A plot of the number of fluorescent GHOST cells with increasing HIV-1_SF162 dose is not linear. It is likely that with high-dose inocula, infection with multiple virus produces additive fluorescence in individual cells. In studies of the neutralization kinetics of IgG1 b12 against these isolates, events during the absorption phase of the assay, as well as the incubation phase, determine the level of neutralization. It is possible that complete inactivation of a virus is limited to the time it is exposed on the cell surface. Assays can be modified so that neutralization of these very low doses of virus can be quantified. A higher concentration of antibody is required to neutralize the same dose of resistant SHIV_SF162P3 than the sensitive SHIV_SF162P4. In the absence of selection during passage, the density of the CCR5 co-receptor on the GHOST cell surface is reduced. Changes in the CD4 : CCR5 density ratio influence neutralization.</p> <p>Conclusions</p><p>Low concentrations of IgG1 b12 completely inactivate small doses of the neutralization resistant SHIV _SF162P3. Assays need to be modified to quantify this effect. Results from modified assays may predict protection following repeated low-dose shiv challenges in rhesus macaques. It should be possible to induce this level of antibody by vaccination so that modified assays could predict the outcome of human trials.</p> </div

FACS analysis of Hi5 GHOST cells at different passage levels.

<p>Fluorescent intensities are plotted on the horizontal axis and the number of cells on the vertical. <b>A</b>. Passage 7; <b>B</b>. Passage 9; <b>C</b>. Passage 11; <b>D</b>. Passage 13; <b>E</b>. Passage 15; <b>F</b>. Passage 17; <b>G</b>. Passage 19; <b>H</b>. Passage 21; <b>I</b>. Passage 23.</p

Comparison of linear regression and fitted second-order plots of reductions in infectious virus in HIV-1 _SF162 - GHOST cell neutralization assays.

<p>Low doses of the relatively neutralization sensitive HIV-1 _SF162 isolate were incubated at 37⁰C for four hours with concentrations of the human monoclonal antibody IgG1 b12. The mixture was then added to GHOST cells and allowed to absorb for 24 hours. The cells were washed and cultured for a further 24 hours (= 4/24/2 assays). Four duplicate cultures were used for each point within a replicate. Parameters are given as means with their standard errors. Regression lines with the formula y = mx + c where y is the number of fluorescent cells plotted on the vertical axis and x is the dose of virus along the horizontal axis. <b>A</b>. Gray: three control replicates where cells were cultured without monoclonal antibody: m = 1.081 ± 0.063; c = -5.187 ± 4.375; green: three replicates where virus were incubated with 0.125 µg/ml IgG1 b12 : m = 0.545 ± 0.042; c = -1.731 ± 2.938. <b>B</b>. Gray: seven control replicates where cells were cultured without monoclonal antibody: m = 1.003 ± 0.037 ; c = -0.300 ± 3.086; blue: seven replicates where virus were incubated with 0.05 µg/ml IgG1 b12 : m = 0.737 ± 0.028; c = -0.409 ± 2.350. <b>C</b>. Gray: two control replicates where cells from early passages were cultured without monoclonal antibody: m = 0.973 ± 0.076; c = 2.409 ± 7.608; red: two replicates where virus were incubated with 0.02 µg/ml IgG1 b12: m = 0.815 ± 0.059; c = -4.545 ± 5.928; D. Gray: four control replicates where cells from later passages were cultured without monoclonal antibody: m = 1.003 ± 0.046; c = -0.301 ± 3.402; red: four replicates where virus were incubated with 0.02 µg/ml IgG1 b12: m = 1.013 ± 0.036; c = -7.313 ± 2.719. Dotted lines are extrapolations to the axes using the formula of the regression / fitted lines. Some data points have been excluded and axes truncated to improve clarity and magnify the situation around the origin.</p

Dose–response plots of HIV-1 _SF162 and SHIV variants on GHOST cells.

<p>GHOST cell cultures were exposed to different doses of virus, plotted on the x-axis (= horizontal). The number of cells which fluoresce after infection is plotted on the y-axis (= vertical). <b>A</b>. Linear regression of HIV-1 _SF162 - infected cultures: y = 1.457 ± 0.066 x -584.3 ± 89.86. <b>B</b>. Fitting of data to second-order (quadratic) equation: y = 4.31 x 10^-4 x² + 0.347 x + 26.63. <b>C</b>. Quadratic plot of SHIV_SF162P4 on GHOST cells: y = -1.03 x 10^-3 x² + 1.349 x + -4.17 x 10^-4. <b>D</b>. Quadratic plot of SHIV_SF162P3 on GHOST cells: y = -7.63 x 10^-5 x² + 0.963x + -4.077.</p

Reductions in infectious titer following exposure of HIV-1_SF162 or SHIV_SF162P4 to monoclonal antibody IgG 1 b12.

<p>Reductions in infectious virus are calculated as the ratio of the titer (V_t) at time t for the virus exposed to antibody divided by the titer (V_c) at the same time for control cultures without antibody. The ratio is transformed to log₁₀ (V_t / V_c). Incubation and absorption phases are measured in hours. Data are displayed as means with standard errors. Plots are regression lines with their 95% confidence band. Horizontal broken line represents 50% neutralization. Green: 1 µg/ml IgG1 b12; Blue: 0.4 µg/ml IgG1 b12; Red: 0.2 µg/ml IgG1 b12. Expected ratio of neutralization rates is the ratio of the antibody concentrations within an individual assay. <b>A</b>. Incubation plots of IgG1 b12 against HIV-1 _<b>SF162</b> (Ratios: Expected 1 µg/ml : 0.4 µg/ml = 2.5; The observed ratio of the gradients of the regression lines = 3.14; p < 0.0001; Expected 1 µg/ml : 0.2 µg/ml = 5; Observed: 8.03p < 0.0001; Expected 0.4 µg/ml : 0.2 µg/ml = 2; Observed = 2.56; p = 0.0251); <b>B</b>. absorption plots of IgG1 b12 against HIV-1 _<b>SF162</b> (Ratios Expected = 2.5; Observed = 1.25; p = 0.4879); C. Incubation plots of IgG1 b12 against SHIV <b>_SF162P4</b> (Ratios: Expected = 2.50; Observed = 2.50; p < 0.0001); D. Absorption plots of IgG1 b12 against SHIV <b>_SF162P4</b> (Ratios: Expected = 2.50; Observed = 1.69; p < 0.02773).</p

Frequencies of DLA class II alleles in 66 ESSs with CH and 84 healthy controls.

<p>Altogether, 10 DRB1 alleles, six DQA1 alleles and eight DQB1 alleles were found in the population. The alleles DRB1*00601and DQB1*00701 were observed in a higher frequency in cases while the alleles DRB1*00501and DQB1*00501 were more frequent in controls. Numbers in bold indicate a significant difference between cases and controls. NS; not significant.</p>*<p>After Bonferroni adjustment, significance level would be p<0.017.</p

Frequencies of three locus DLA class II haplotypes in 66 ESSs with CH and 84 healthy controls.

<p>A total of 11 different haplotypes with frequencies >1% were identified. DLA-DRB1*00601/DQA1*005011/DQB1*00701 (haplotype four) had an increased frequency in cases and DLA-DRB1*00501/DQA1*00301/DQB1*00501 (haplotype eight) was significantly more frequent in controls, both numbers shown in bold. A p value for significance was set at 0.05 for comparison of haplotype frequencies.</p

Idiopathic hepatitis liver datasets: a) Read reduction following mapping subtraction and k-mer similarity filtering.

<p>b) Effect of k-mer filtering (K-mer) & host mapping subtraction (Map) on post-assembly contig number. c) Effect of k-mer filtering (K-mer) & host mapping subtraction (Map) on viral contig size and reference coverage.</p

Effect of viral reference coverage of Illumina reads (red text), host mapping subtraction (Map), k-mer filtering (k-mer) and low-complexity filtering (LC) on viral contig size and reference coverage (post-assembly) using CLC assembler (v.6) at optimal word size.

<p>Effect of viral reference coverage of Illumina reads (red text), host mapping subtraction (Map), k-mer filtering (k-mer) and low-complexity filtering (LC) on viral contig size and reference coverage (post-assembly) using CLC assembler (v.6) at optimal word size.</p