Method of analyzing cell samples, by creating and analyzing a resultant image

• US 7,155,050 B1
• Filed: 10/31/2000
• Issued: 12/26/2006
• Est. Priority Date: 11/03/1999
• Status: Expired due to Fees

• Current Assignee: GE Healthcare Bio-Sciences AB (GE Healthcare Technologies, Inc.)
• Original Assignee: GE Healthcare Bio-Sciences AB (GE Healthcare Technologies, Inc.)
• Inventors: Bjorkesten, Lennart, Soderman, Tobias, Sloge, Erik
• Primary Examiner(s): EDWARDS, PATRICK L
• Assistant Examiner(s): EDWARDS, PATRICK L
• Application Number:
  US10/129,448
• Time in Patent Office: 2,247 Days
• Field of Search: 382/133, 382/134, 377/10, 702/26, 435/4, 435/6, 436/172, 204/459, 204/461, 204/462
• US Class Current: 382/133
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06V 20/69 Microscopic objects, e.g. biological cells or cellular parts

Abstract

A method is provided for comparing multiple samples of cell extract containing a plurality of components. The method comprises the steps of preparing at least two samples of cell extract from at least two groups of cells and of exposing each of said sample of said cell extract to a different one of a set of matched markers, e.g. luminescent markers, to bind the marker to the cell extract to label the cell extract, each marker within said set of markers being capable of binding to the cell extract and can be individually detected from all other markers within said set. The samples are then mixed to form a mixture and said mixture is electrophoresed to separate the components within the cell extract. At least two electronic images of the electrophoresed mixture are obtained (I) by detection of the individual markers, each image being represented by detection of a marker different from the others. One resultant electronic image (I_res) of the obtained at least two electronic images is created (II) and analyzed in order to identify spot analysis areas (III). The identified spot analysis areas are applied on the respective at least two electronic images for evaluating said areas in order to detect spots representing components of said cell extracts (IV).

Claims

1. In a method of comparing multiple samples of cell extract containing a plurality of components comprising:

preparing at least two samples of cell extract from at least two groups of cells;

exposing each of said samples of said cell extract to one of a set of matched markers to bind the marker to the cell extract to label the cell extract, each marker within said set of markers being capable of binding to the cell extract and can be individually detected from all other markers within said set;

mixing said samples of labeled cell extract to form a mixture;

separating said mixture to separate the components within the cell extract;

obtaining at least two electronic images of the separated mixture by detection of the individual markers, each image being represented by detection of a marker different from the others;

the improvement comprising;

creating one resultant electronic image (I_res) of the obtained at least two electronic images by additively combining corresponding pixel intensity values (p₁, . . . , p_n;

p′

₁, . . . , p′

_N) according to predetermined function;

analyzing the resultant image in order to identify spot analysis areas, wherein the spot analysis areas are subjected to a filtration step in order to classify the areas according to predetermined criteria related to the three dimensional topography of said areas; and

applying said identified spot analysis areas on the respective at least two electronic images for evaluating said areas in order to detect spots representing components of said cell extracts.

2. The method of claim 1, wherein said separation is performed by electrophoresis.

3. The method of claim 2, wherein said set of markers comprise a luminescent set of dyes that covalently bind to the cell extract to label the cell extract, each dye within said set of dyes being capable of covalently binding to the cell extract and having generally the same ionic and pH characteristics as all other dyes within said set of dyes and emitting light at a wavelength sufficiently different from all other dyes within said set of dyes to present a different colored light.

4. The method of claim 1 further comprising:

determining a degree of similarity between pixel intensity values in the applied corresponding spot analysis areas in the two electronic images.

5. The method of claim 4, wherein said degree of similarity is determined by the Pearson Correlation method.

6. The method of claim 1, wherein the number of spot analysis areas to be identified in the resultant image is set to 800.

7. The method of claim 1, further comprising:

comparing corresponding detected spots by forming a differential expression (DE) between predetermined parameters of said detected spots.

8. The method of claim 7, wherein the differential expressions are normalised and arranged in a histogram.

9. The method of claim 8, wherein the predetermined parameters representing under and over expressed corresponding spots are set in a histogram.

10. The method of claim 9, wherein said predetermined function is a summation (P_1res=(p₁+p′

₁)/2) of corresponding pixel intensity values.

11. The method of claim 9, wherein in said predetermined function, each resultant pixel intensity value is determined as p_1res=√

{square root over (p₁2+p₁′

2)}.

12. The method of claim 1, wherein said method further comprises an alignment step to be performed before creating the resultant electronic image (I_res) in order to align the electronic images so that corresponding spots coincide.

13. The method of claim 12, wherein said alignment step includes one of or a combination of the following substeps:

aligning the at least two electronic images with respect to each other;

applying a linear transformation, or

applying a stretching function.

14. The method of claim 1, wherein said method is controlled via a user interface display comprising a predetermined number of predefined changeable views, all simultaneously available, each being a graphical or a numerical representation of different steps performed, wherein said representation comprises graphical or numerical objects of spots or spot analysis areas, where corresponding objects are linked together in the different views.