METHOD FOR EARLY DIAGNOSIS OF RHEUMATOID ARTHRITIS Russian patent published in 2020 - IPC G01N33/577 

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to rheumatology, and can be used for early diagnosis of rheumatoid arthritis. Method consists in adding monoclonal antibodies to TNFRI, TNFR2, CD4, CD45R0, CD45RA, CD3 into a blood sample; peripheral blood mononuclear cells are analyzed by flow cytometry. CD3^+--T-lymphocytes, naive T-helper cells (CD4⁺CD45RA⁺), T-helper memory cells (CD4⁺CD45R0⁺) are isolated by gating. Further, the TNFR1 and TNFR2 receptor expression values are determined by counting the number of receptors on the cells of the studied subpopulations, the percentage of cells carrying the TNFRI and TNFR2 receptors is determined in each selected subpopulation, after which based on parametric logistic regression model is calculated probability of presence of rheumatoid arthritis by formula

where e = 2.7182818 - mathematical constant - base of natural logarithm, α₀ = 2.386696717005736 - coefficient, α₁ = -0.00276285111326 - coefficient, α₂ = 0.00189985337763 - coefficient, α₃ = -0.28206543500757 - coefficient, x₁ - number of receptors TNFR2 on CD3⁺ T-lymphocytes, x₂ - amount of TNFR1 on T-helper cells CD4⁺CD45R0⁺, x₃ - percentage TNFR1 positive cells among naive T-helper cells CD4⁺CD45RA⁺. If value P ≥ 0.5 there is a probability of rheumatoid arthritis.

EFFECT: use of this method for mononuclear subpopulations estimation: TNFR1+TNFR2 cells, cells among naive T-helper cells and number of type 1 receptors on T-helper memory cells, as well as type 2 receptors on CD3⁺ T-cells enables distinguishing indicators of healthy donors and rheumatoid arthritis patients at an early stage.

3 cl, 2 tbl, 5 ex, 1 dwg