In vitro testing methods for late hair-hair allergic reactions Skin testing and the induction of contact allergy are two common methods for detecting late hair-inducing allergic reactions (DTH).
In skin tests, a re-response to antigens that had made the patient sensitive was induced, and contact allergy was the ability to test the recipient's ability to be sensitive to substances that had never been exposed. 1. Skin test with skin test diagnosis DTH, commonly used antigens have TB bacteria pure protein derivatives (PPD), mumps virus, candidadein, etc. , in human tests in the forearm skin injection of a small amount of soluble antigen, 24 to 48 small, measure the size of red and swollen hard knots, hard knot diameter greater than 10mm is considered positive. It shows that the subject has a certain degree of cellular immunity to the pathogen, if the skin test does not respond, can use a higher concentration of antigen repeated test, if still no response is negative, it is necessary to exclude the skin test technical error, may also be the subject has never been exposed to this antigen, may also be due to cell immune function deficiency, or due to cellular immune function deficiency,
or non-reactive due to severe infections (measles, chronic diffuse TB). 2. Contact allergies often apply low molecular weight compounds such as dinitrol chlorobenzene (DNCB) induced contact allergy. Compounds bind to skin proteins to induce DTH reactions. In animal tests, the skin appears positive if the skin appears positive after 7 to 10 days of stimulation after the first time the DNCB is applied to the skin.
This experiment is no longer used by humans.
In vitro detection method of cell immunity In vitro detection of the number and function of lymphocytes, more easy to collect blood samples, first of all need to isolate or purify lymphocytes, generally using glutalyson-panphotonic glutamine with a proportion of 1.077 lymphocytes stratification fluid, when the blood overlaps on top of lymphocytes stratified liquid centrifugation, due to red blood cells (1.092), polymorphic nuclear white blood cells (primarily 1.090), the proportions of lymphocytes (1.070) are different and separated from each other. Lymphocytes and monocytes form a thin layer at the junction of plasma and stratification.
Carefully divide this thin layer of cells, of which lymphocytes accounted for 80%, mononucleosis accounted for 20%, lymphocytes accounted for 80%, B cells accounted for 4% to 10%, as non-DT, non-B cells. ⑴ E-garland: human T cell surface has SRBC receptor (CD2) can bind to SRBC to form a rose ring-like structure, the RBM suspension and SRBC isolated by layered liquid mixed in a balanced saline containing serum, cultured at 37 degrees C 5 to 10 minutes put 4 degrees C overnight, take the cell suspension count, Peripheral blood lymphocytes in about 70% to 80% of lymphocytes form wreaths, or T cells.
Currently this method has been used to isolate T cells without having to do T-cell counting. (2) Counting T cells with monoclonal antibodies: the human PBM is divided into three equal parts, the pre-antibodies of mice anti-human CD3, CD4 and CD8 are combined with the cells, and then the second antibody of the rabbit anti-mouse IgG labeled by FITC is used for indirect immunofluorescent staining, In the results of fluorescence microscope or flow cytometer test results, in PBM cd3 antibodies dyed fluorescent cells called CD3-plus cells, or total T cells. Normal people in PBM T cells accounted for 70% to 80%. The sum of CD4-plus cells and CD8-cells in normal people should be consistent with the number of CD3-cells. The ratio of CD4-plus cells to CD8-cells is about 2/1 for normal people, while the ratio of AIDS patients is less than 1.7.