动物造模,药效评价,自身免疫性抗体被动转运 z-bio 2024-07-29 417

　　1. Rabbit corneal autoimmune antibody passive transport model IgG was obtained from patients with bullous pemphigoid (BP) and injected into the cornea of New Zealand rabbits. After 24 hours, the cornea showed epidermal separation, thickening, and blister formation. The inflammatory response is dose-dependent, with linear deposition of IgG and C3 visible at the junction of the epidermis. However, this model has been rarely used since then.

　　2. Passive Transport Model of Autoimmune Antibodies in Newborn Mice

　　(1) IgG was taken from patients with pemphigus vulgaris (PV) and injected intraperitoneally into newborn BALB/c mice at a dose of 1.5-16mg/g body weight per day. Within 18-72 hours, dose-dependent skin blisters or extensive epidermal collapse were observed. Stop administering IgG and the development of skin lesions will cease. Because injection of F (ab) 2 fragment can also cause similar skin lesions, it suggests that Fc may not be involved in this reaction.

　　(2) IgG was taken from patients with pemphigus vulgaris (PF) and injected intraperitoneally into neonatal BALB/C mice at a dose of 2 × 10mg/g body weight per day, for a total of 4 times. Similar to PV, the skin lesions observed in mice exhibit dose and titer dependence.

　　(3) In the BP model, due to the lack of cross antigen between the mouse transmembrane protein BP180 and the immune domain NC16A of human BP180, it is necessary to construct the fusion protein GST-mus180A. Immune rabbits with fusion protein to obtain IgG, and then inject IgG into newborn mice. Within 24 hours, the mice showed erythema and skin laxity, and histology showed subepidermal vesicles and neutrophil infiltration. Direct immunofluorescence showed the deposition of IgG and complement at the junction of the true epidermis.

　　(4) Mucosal pemphigus vulgaris (MMP) model was established by immunizing rabbits with laminin 332 extracted from human keratinocyte culture, and then immunizing neonatal mice with IgG extracted from rabbit blood. Method: Intraperitoneal or subcutaneous injection. If the total amount exceeds 5mg/kg, tension blisters will appear on the skin friction or injection site within 48 hours. The formation of blisters is not related to complement or mast cells, indicating that Fc is not involved in pathogenesis.

　　3. Passive transport model of autoimmune antibodies in adult mice

　　(1) Establishment of Acquired Bullous Epidermal Release (EBA) Model: Rabbits were immunized with mouse NC1 immune determinants or human type VII collagen as antigens, and then mice were immunized with the obtained rabbit polyclonal antibodies, injected at a dose of 0.3-0.9mg/g body weight. After 2-4 days, dose-dependent formation and erosion of subepidermal vesicles can be observed, and histological examination reveals neutrophil infiltration and IgG/C3 deposition at the junction of the true epidermis. Among them, inbred nude mice, BALB/C, C57BL/6, and closed group SKH-1 mice are sensitive to type VII collagen antibodies.

　　(2) MMP model: Injection of anti human laminin 332 rabbit IgG antibody into mice can cause local erythema, erosion, and scab formation within 24 hours. Histological examination shows IgG and C3 deposition, but no subepidermal vesicles or neutrophil infiltration.

　　(2) MMP model: Injection of anti human laminin 332 rabbit IgG antibody into mice can cause local erythema, erosion, and scab formation within 24 hours. Histological examination shows IgG and C3 deposition, but no subepidermal vesicles or neutrophil infiltration.

　　The passive transport model of autoimmune antibodies in mice receiving human epidermal transplantation or humanized mice can be divided into two pathways.

　　(1) After injecting serum from patients with pemphigus vulgaris, only a portion of nude mice receiving oral mucosal transplantation were able to induce blister formation. And human IgG can be detected in all mouse skin, with nearly 60% of transplants showing edema in the basal layer of the epidermis. Recently, healthy full thickness skin grafts have also been applied to SCID mice, and then injected with IgG fragments of human serum (total dose 20mg). Mild erythema can be observed after 48 hours. Histological examination revealed that after injection of anti-Dsg1, blisters appeared on the upper part of the stratum spinosum or below the stratum corneum; After injection of Dsg3, spinous release blisters appeared on the basal layer. Direct immunofluorescence shows in situ deposition of IgG.

　　Pathogenicity study of anti MMP antibodies in vivo: SCID mice receiving human epidermal grafts injected with rabbit anti laminin 332 IgG or human MMP isolated IgG may exhibit local erythema, erosion, and scabbing.

　　(2) Application of humanized mouse model: In terms of humanized type 17 collagen deficient mouse BP model, a humanized mouse model was first constructed. The clinical manifestations were similar to those of non Herlitz bullous epidermal release type 17 collagen gene knockout mice, which could express human type 17 collagen by backcrossing with C57B1/6Ncr mice. At this point, if serum or high affinity IgG (0.05-2mg/g body weight) is administered to BP patients, diffuse erythema may appear within 48 hours. Histology shows separation between true epidermis, infiltration of inflammatory cells (neutrophils, lymphocytes) with deposition of IgG and C3.