Methods and means for monitoring disruption of tissue homeostasis in the total body

1. A method for determining the health status of a subject, for early detection of tissue damage, for early diagnosis and monitoring of a disease, and/or for evaluation of treatment effectiveness in a subject using circulating tissue macrophages as a mirror of disrupted tissue homeostasis and disease, the method comprising the steps of:

a) providing a peripheral blood sample from the subject which contains circulating tissue macrophages (CTM);

b) staining said CTM with a panel of differentially-labeled distinct antibodies against the backbone markers CD14, CD16 and CD300e for the identification and enumeration of different CTM subsets;

c) fixation, permeabilization and staining of the CTM using one or more detecting antibodies directed against one or more epitopes on at least one protease-induced protein fragments derived from intracellular degradation of a non-CTM protein by individual CTM in their tissues of origin, thereby identifying at least one subset of circulating tissue-specific macrophages (CTSM);

d) multiparameter flow-cytometric analysis of said stained CTM and CTSM by gating for the backbone markers CD14, CD16 and CD300e to determine the amount of signals of each distinct labeled antibody associated with individual cells, wherein the analysis comprises performing a gating strategy based on the cell surface expression of CD300e, CD14 and CD16, in combination with side scatter (SSC) analysis, and wherein the gating strategy is composed of (i) an inclusion step to include both classical monocytes and CTMs based on CD300e expression in combination with side scatter (SSC) analysis, and (ii) a subsequent subset identification step to discriminate the classical CD14high/CD16−;

e) determining the relative and absolute number of individual cells within each CTM subset and each specific subset of CTSM that express each of the measured intracellular epitopes;

f) calculating (i) the relative and absolute number of cells within each CTM subset and each specific subset of CTSM which each originate from different normal and altered tissues as defined by a set of individual protease-induced protein fragments evaluated, and ii) the amount of antibody-related signal associated to every individual intracellular peptide evaluated to obtain a test CTSM staining profile, and;

g) comparing the test CTSM staining profile with a normal CTSM staining profile for each tissue evaluated, wherein an aberrant test staining profile is indicative of tissue damage, an altered tissue homeostasis, the presence of a disease, and/or treatment effectiveness versus resistance.

2. The method according to claim 1 , wherein the subset identification step comprises the identification of classical (CD14high/CD16−) monocytes and two main CTM subsets identified as CD14high/CD16low to CD14high/CD16high, CD14low/CD16high, and CD14−/CD16high to CD14−/CD16low cells.

3. The method according to claim 1 , wherein step c) comprises intracellular staining of one or more of the following:

a. one or more epitopes of a single protease-induced protein fragment derived from an intracellularly processed tissue-associated protein;

b. one or more epitopes of two or more distinct protease-induced protein fragments derived from one intracellularly processed tissue-associated protein;

c. one or more epitopes of two or more distinct protease-induced protein fragments derived from two or more intracellularly processed proteins derived from normal cells from a single organ or tissue;

d. one or more epitopes of two or more distinct protease-induced protein fragments derived from two or more intracellularly processed proteins derived from abnormal cells from a single organ or tissue;

e. one or more epitopes of two or more distinct protease-induced protein fragments derived from two or more intracellularly processed proteins derived from normal and abnormal cells from a single organ or tissue, including a combination of at least one antibody against peptide epitopes of a normal protein and at least one antibody against peptide epitopes from an aberrant protein, and;

f. one or more epitopes of two or more distinct protease-induced protein fragments derived from two or more intracellularly processed proteins derived from normal or abnormal cells from two or more organs or tissues.

4. The method according to claim 3 , wherein step c) comprises intracellular staining of one or more epitopes of a single protease-induced protein fragment derived from an intracellularly processed tissue-associated protein.

5. The method according to claim 1 , wherein the at least one detecting antibodies allows for detection of one or more peptide epitopes derived from an aberrant protein.

6. The method according to claim 5 , wherein the aberrant protein is selected from the group consisting of oncogenic proteins, mutated proteins, fusion proteins, proteins derived from an allergen and proteins derived from a pathogen.

7. The method according to claim 6 , wherein the aberrant protein is selected from the group consisting of oncogenic proteins.

8. The method according to claim 6 , wherein the pathogen is a virus, a bacterium, a parasite or a fungus.