Journal: PLoS Medicine

Article Title: A Microchip CD4 Counting Method for HIV Monitoring in Resource-Poor Settings

doi: 10.1371/journal.pmed.0020182

Figure Lengend Snippet: Purified CD4 cells were labeled with AlexaFluor-488-conjugated anti-CD4 antibodies, introduced to the flow cell in amounts ranging from zero to 200,000 cells and imaged. There is a linear correlation between the number of cells in the sample and the intensity of light emitted from the membrane filter ( R 2 = 0.999).

Article Snippet: Single-purpose flow cytometers have been designed solely for counting CD4 cells, such as the Becton Dickinson FACSCount, the Partec CyFlow, and desktop instruments from Guava and PointCare Technologies.

Techniques: Purification, Labeling, Membrane

Journal: PLoS Medicine

Article Title: A Microchip CD4 Counting Method for HIV Monitoring in Resource-Poor Settings

doi: 10.1371/journal.pmed.0020182

Figure Lengend Snippet: A total of 16.5 μl of whole blood stained with antibodies specific for CD4 and CD3 markers is delivered to the flow cell after 8 min, and an image of the same region of the membrane is obtained with two different emission filters. (A) AlexaFluor-488-conjugated anti-CD4 antibody stains CD4 + cells (T lymphocytes and monocytes) green. (B) AlexaFluor-647-conjugated anti-CD3 antibody stains CD3 + T lymphocytes red. (C) By digitally merging the two images, CD3 + CD4 + T lymphocytes (i.e., “CD4 cells”) appear yellow and are distinguished from CD4 + CD3 − monocytes (green) and CD3 + CD4 − T lymphocytes (red). (D) A lymphocyte selection algorithm is applied to the merged image, based on a lymphocyte profile as defined by size, shape, and uniformity. Objects not fitting the lymphocyte profile are deleted while remaining objects are selected and ultimately counted. A similar protocol to count CD8 cells is used in each participant. Boxed region indicates two CD4 + cells (yellow in [C]) in the original (A and B), merged (C), and processed (D) images. Large green and red objects seen in some images represent aggregates of fluorescent antibody.

Article Snippet: Single-purpose flow cytometers have been designed solely for counting CD4 cells, such as the Becton Dickinson FACSCount, the Partec CyFlow, and desktop instruments from Guava and PointCare Technologies.

Techniques: Staining, Membrane, Selection

Journal: PLoS Medicine

Article Title: A Microchip CD4 Counting Method for HIV Monitoring in Resource-Poor Settings

doi: 10.1371/journal.pmed.0020182

Figure Lengend Snippet: The participants included (A) a 31-y-old woman with a CD4 count of 83 cells/μl by flow cytometry; (B) a 33-y-old woman with a CD4 count of 271 cells/μl by flow cytometry; and (C) a 5-mo-old infant with an absolute CD4 count of 2,098 cells/μl and a CD4:CD8 ratio of 1.80 by flow cytometry. In these images, CD3 + CD8 + T cells appear red, monocytes appear green, and CD3 + CD4 + T cells appear yellow. Each image reflects 0.18 μl of whole blood.

Article Snippet: Single-purpose flow cytometers have been designed solely for counting CD4 cells, such as the Becton Dickinson FACSCount, the Partec CyFlow, and desktop instruments from Guava and PointCare Technologies.

Techniques: Flow Cytometry

Journal: PLoS Medicine

Article Title: A Microchip CD4 Counting Method for HIV Monitoring in Resource-Poor Settings

doi: 10.1371/journal.pmed.0020182

Figure Lengend Snippet: Bland–Altman methods comparison plot comparing absolute CD4 cells per microliter of whole blood obtained by the microchip system as compared to standard four-color flow cytometry processed in parallel on a FACSCalibur in 61 HIV-infected adult participants. There is a proportional bias of −50 cells/μl relative to flow cytometry. Grey line indicates zero bias. Red lines indicate upper and lower 95% limits of agreement.

Article Snippet: Single-purpose flow cytometers have been designed solely for counting CD4 cells, such as the Becton Dickinson FACSCount, the Partec CyFlow, and desktop instruments from Guava and PointCare Technologies.

Techniques: Comparison, MicroChIP Assay, Flow Cytometry, Infection

Journal: PLoS Medicine

Article Title: A Microchip CD4 Counting Method for HIV Monitoring in Resource-Poor Settings

doi: 10.1371/journal.pmed.0020182

Figure Lengend Snippet: (A and B) CD4 percentages of total T cells and (C and D) CD4:CD8 ratios in 67 human participants, including 61 adults and six children. In Passing–Bablok correlation plots (A and C), solid black lines indicate identity, blue lines indicate the observed correlations, and dashed black lines indicate 95% confidence limits. Correlations for CD4 percentages of total T cells ( r = 0.98, p < 0.0001) and CD4:CD8 ratios ( r = 0.98, p < 0.0001) are shown. For Bland–Altman methods comparison plots (B and D), notations are as described in caption.

Article Snippet: Single-purpose flow cytometers have been designed solely for counting CD4 cells, such as the Becton Dickinson FACSCount, the Partec CyFlow, and desktop instruments from Guava and PointCare Technologies.

Techniques: Comparison

Journal: Pharmaceuticals

Article Title: Identification of a Potent Allosteric Inhibitor of Human Protein Kinase CK2 by Bacterial Surface Display Library Screening

doi: 10.3390/ph10010006

Figure Lengend Snippet: Flow cytometer analysis of E. coli cells displaying α S1 -casein (170 aa) ( A ) and α S1 -casein peptide (16 aa) ( B ) after incubation with fluorophore coupled CK2. By the use of a FACSAria flow cytometer 50,000 cells were analyzed with an exication wavelength of 488 nm and an emission wavelength between 527 and 530 nm. The host strain E. coli UT5600(DE3) was outlined in the same manner (grey line). ( A ): E. coli UT5600(DE3) pKP10; ( B ): E. coli UT5600(DE3) pKP6.

Article Snippet: For each experiment at least 10,000 cells were analyzed with a FACSAria III instrument (Becton-Dickinson, Heidelberg, Germany) with a ACDV option for sorting experiments or with a CyFlow Space (Partec, Münster, Germany) for analysis.

Techniques: Flow Cytometry, Incubation

Journal: Pharmaceuticals

Article Title: Identification of a Potent Allosteric Inhibitor of Human Protein Kinase CK2 by Bacterial Surface Display Library Screening

doi: 10.3390/ph10010006

Figure Lengend Snippet: Flow cytometer analysis of E. coli cells displaying library peptides and sorting of cells with increased fluorescence. The analysis of 10,000 cells was accomplished with a FACSAria Cytometer with an integrated sorting module. The cells were incubated with fluorophore coupled CK2 and analyzed at a excitation wavelength of 488 nm and an emission wavelength between 527 and 530 nm. A sort gate was drawn around the population with an increased green fluorescence, which represent 0.54% of all events. These cells were selected out and grown on a agar plate for further analysis.

Article Snippet: For each experiment at least 10,000 cells were analyzed with a FACSAria III instrument (Becton-Dickinson, Heidelberg, Germany) with a ACDV option for sorting experiments or with a CyFlow Space (Partec, Münster, Germany) for analysis.

Techniques: Flow Cytometry, Fluorescence, Cytometry, Incubation