CEACAM1 based point-of-care cancer diagnostic

Abstract

The present technology regards the utilization of CEACAM1 as a biomarker for cancer. In particular the present invention regards the detection and measurement of soluble CEACAM1 levels for the detection and diagnosis of melanoma.

Claims

1. A device for the point-of-care detection of melanoma in a patient, the device configured to detect soluble Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) level in a biological sample from the patient having melanoma, the device comprising: an immunochromatographic strip comprising a sample loading zone, a reaction zone having a mobile phase comprising a first CEACAM1 antibody conjugated to a detectable moiety; and a CEACAM 1 capture zone comprising an immobilized CEACAM1 binding agent; wherein said first CEACAM1 antibody binds to the CEACAM1 A2 domain, and said immobilized CEACAM1 binding agent is a member the CEA protein family; and wherein a detectable signal accumulates in the capture zone when the biological sample comprises at least 30 ng/ml soluble CECAM1.

Description

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

(1) FIG. 1. Presentation of data showing that soluble CEACAM1 is increased in melanoma patients.

(2) FIG. 2. Schematic representation of an immunochromatographic strip for the point-of-care detection of CEACAM1 in a biological sample.

(3) FIG. 3. Schematic representation of one embodiment of a lateral-flow point-of-care rapid detection system, for the detection and measurement of CEACAM1 in a test sample.

(4) FIG. 4. Presentation of data showing that soluble CEACAM1 is increased in melanoma patients.

DETAILED DESCRIPTION OF THE INVENTION

(5) The present technology generally regards the use of soluble CEACAM1 for the diagnosis and for predicting the prognosis of cancer, including for example melanoma. The present technology also comprises in part a immunochromatographic strip for the point-of-care detection of CEACAM1 in a biological sample.

(6) CEACAM1 appears as a soluble molecule in the peripheral blood. The present technology regards the diagnosis of cancer comprising the detection of soluble CEACAM1 in a biological sample. The data presented in FIG. 1 and FIG. 4 demonstrate that soluble CEACAM1 levels function as a biomarker for at least one type of cancer, namely melanoma (a form of skin cancer that begins in melanocytes (the cells that make the pigment melanin). As shown in FIG. 1, soluble CEACAM1 is increased in melanoma patients (LR (Low Risk); HR (High Risk); Met (Metastatic patients); healthy donors). Soluble CEACAM1 is quantified using a CEACAM1 specific sandwich ELISA. For example, the specific anti-CEACAM1 5F4 mAb can be used as capturing antibody. For detection, biotinylated Kat4c mAb can be used, followed by streptavidin-horseradish peroxidase (Jackson ImmunoResearch). Biotinylation of the Kat4c mAb can be performed with Sulfo-NHS-SS-Biotin (Pierce) according to the manufacturer's instructions. The quantification can then be calculated according to standard samples of CEACAM1-Ig fusion proteins.

(7) FIG. 2 is an schematic illustration of one aspect of the present technology. Referenced generally as 1 is a immunochromatographic strip comprising a matrix material 2 having an application (or sample loading) zone 3, a reaction zone 4, a CEACAM1 capture zone 5, a control analyte capture zone 6, and an optional wicking pad 7.

(8) The test fluid (and any CEACAM1 suspended or dissolved therein) is first brought into contacted with or applied to the application zone 3 of the immunochromatographic strip 1. The immunochromatographic strip 1 comprises a matrix material 2 which facilitates the test fluid moving by capillarity action from the application zone 3 through the reaction zone 4 and past the capture zones (CEACAM1 capture zone 5 and control analyte capture zone 6) to an optional wicking pad 7. Any detectable signal in the capture zones will reveal the presence of analyte (CEACAM1 or control).

(9) The matrix material comprises a membrane material, for example nitrocellulose membrane, cellulose acetate membrane, glass-fiber membrane, or any combinations or derivatives thereof. The matrix material is porous, and any test liquid or sample applied to the matrix material at application zone 3 can move by capillary into the reaction zone 4 and continue to and/or past the capture zones 4 and 5.

(10) The reaction zone 4 contains a mobile phase comprising a first CEACAM1 specific antibody (or fragment thereof) conjugated to a detectable moiety (e.g. radioactive isotopes, enzymes, dyes, fluorescent dyes, dyed microspheres, affinity tag, or any combination or derivative thereof). The reaction zone 4 will also comprise, in mobile phase, a first control analyte specific antibody conjugated to a detectable moiety. When the test sample (and any CEACAM) moves by capillary action out of the application zone 3 and into the reaction zone 4, an antigen-antibody reaction ensues resulting in any CEACAM1 becoming bound (in mobile phase) by a first CEACAM1 specific antibody (or fragment thereof) conjugated to a detectable moiety. See FIG. 3.

(11) The antigen (CEACAM1)-antibody reaction product formed within the reaction zone then migrates with the test liquid into one or more downstream capture zones having immobilized or stationary antibody. The CEACAM1 capture zone 5 comprises an immobilized or stationary phase second CEACAM1 binding element (e.g.a second CEACAM1 antibody or fragment thereof) or CEACAM1 capture agent (e.g.CEACAM1 capture antibody). The control analyte capture zone 6 also comprises an immobilized or stationary phase second control analyte binding element (e.g.a second control analyte antibody or fragment thereof) or control analyte capture agent (e.g.control analyte capture antibody). See FIG. 3.

(12) As a result of capillary flow from the application zone 3 through the reaction zone 4 and into the capture zones 5 and 6, a concentration of the detectable moiety builds within the capture zones, and the concentration of CEACAM1 in capture zone 5 (and control analyte(s) in capture zone 6) can then be assessed qualitatively or quantitatively with a suitable measuring instrument, or if dyes that are adsorbent in the visible range are used as the detectable moiety, can be perceived with the naked eye (FIG. 3).

(13) The detection moiety can be radioactive isotopes, enzymes, dyes, fluorescent dyes, dyed microspheres, affinity tag, or any combination or derivative thereof.

(14) The CEACAM1 binding agent (or capture agent) include without limitation an antibody (or fragment thereof) specific for CEACAM1. The antibody can be either polyclonal or monoclonal. Exemplar CEACAM1 specific antibodies include: Mouse monoclonal [29H2] to CEACAM1; Mouse monoclonal [GM8G5] to CEACAM1 (GM8G5 recognizes the Human CEACAM1 A2 domain); CEACAM1 antibody number 2037.00.02 (from Strategic Diagnostics Inc) binding CEACAM1 amino acids 35-134; the CEACAM1-specific antibody 4D1/C2; anti-CEACAM1 5F4 mAb; anti-CEACAM1 Kat4c mAb; or any combination or derivative thereof. The CEACAM1 binding agent can also be a member of the CEA protein family.