Mice, Inbred MRL lpr: A mouse substrain that is genetically predisposed to the development of systemic lupus erythematosus-like syndrome, which has been found to be clinically similar to the human disease. It has been determined that this mouse strain carries a mutation in the fas gene. Also, the MRL/lpr is a useful model to study behavioral and cognitive deficits found in autoimmune diseases and the efficacy of immunosuppressive agents.Lupus Erythematosus, Systemic: A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.Autoimmune Diseases: Disorders that are characterized by the production of antibodies that react with host tissues or immune effector cells that are autoreactive to endogenous peptides.Antibodies, Antinuclear: Autoantibodies directed against various nuclear antigens including DNA, RNA, histones, acidic nuclear proteins, or complexes of these molecular elements. Antinuclear antibodies are found in systemic autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, scleroderma, polymyositis, and mixed connective tissue disease.Lupus Nephritis: Glomerulonephritis associated with autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Lupus nephritis is histologically classified into 6 classes: class I - normal glomeruli, class II - pure mesangial alterations, class III - focal segmental glomerulonephritis, class IV - diffuse glomerulonephritis, class V - diffuse membranous glomerulonephritis, and class VI - advanced sclerosing glomerulonephritis (The World Health Organization classification 1982).Sialadenitis: INFLAMMATION of salivary tissue (SALIVARY GLANDS), usually due to INFECTION or injuries.Autoantibodies: Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.Lymphatic Diseases: Diseases of LYMPH; LYMPH NODES; or LYMPHATIC VESSELS.Lupus Vulgaris: A form of cutaneous tuberculosis. It is seen predominantly in women and typically involves the NASAL MUCOSA; BUCCAL MUCOSA; and conjunctival mucosa.Mice, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.Lymphoproliferative Disorders: Disorders characterized by proliferation of lymphoid tissue, general or unspecified.Dacryocystitis: Inflammation of the lacrimal sac. (Dorland, 27th ed)Autoimmunity: Process whereby the immune system reacts against the body's own tissues. Autoimmunity may produce or be caused by AUTOIMMUNE DISEASES.Lacrimal Apparatus: The tear-forming and tear-conducting system which includes the lacrimal glands, eyelid margins, conjunctival sac, and the tear drainage system.Antigens, CD95: A tumor necrosis factor receptor subtype found in a variety of tissues and on activated LYMPHOCYTES. It has specificity for FAS LIGAND and plays a role in regulation of peripheral immune responses and APOPTOSIS. Multiple isoforms of the protein exist due to multiple ALTERNATIVE SPLICING. The activated receptor signals via a conserved death domain that associates with specific TNF RECEPTOR-ASSOCIATED FACTORS in the CYTOPLASM.Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Vasculitis: Inflammation of any one of the blood vessels, including the ARTERIES; VEINS; and rest of the vasculature system in the body.Proteinuria: The presence of proteins in the urine, an indicator of KIDNEY DISEASES.Glomerulonephritis: Inflammation of the renal glomeruli (KIDNEY GLOMERULUS) that can be classified by the type of glomerular injuries including antibody deposition, complement activation, cellular proliferation, and glomerulosclerosis. These structural and functional abnormalities usually lead to HEMATURIA; PROTEINURIA; HYPERTENSION; and RENAL INSUFFICIENCY.Spleen: An encapsulated lymphatic organ through which venous blood filters.Hemoglobinuria: The presence of free HEMOGLOBIN in the URINE, indicating hemolysis of ERYTHROCYTES within the vascular system. After saturating the hemoglobin-binding proteins (HAPTOGLOBINS), free hemoglobin begins to appear in the urine.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Mice, Inbred C3HDisease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Mice, Inbred C57BLSplenomegaly: Enlargement of the spleen.Nephritis: Inflammation of any part of the KIDNEY.B-Lymphocytes: Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.Lupus Vasculitis, Central Nervous System: Central nervous system vasculitis that is associated with SYSTEMIC LUPUS ERYTHEMATOSUS. Clinical manifestations may include DEMENTIA; SEIZURES; CRANIAL NERVE DISEASES; HEMIPARESIS; BLINDNESS; DYSPHASIA; and other neurological disorders.Mice, Inbred BALB CSjogren's Syndrome: Chronic inflammatory and autoimmune disease in which the salivary and lacrimal glands undergo progressive destruction by lymphocytes and plasma cells resulting in decreased production of saliva and tears. The primary form, often called sicca syndrome, involves both KERATOCONJUNCTIVITIS SICCA and XEROSTOMIA. The secondary form includes, in addition, the presence of a connective tissue disease, usually rheumatoid arthritis.Antigen-Antibody Complex: The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.snRNP Core Proteins: The protein components that constitute the common core of small nuclear ribonucleoprotein particles. These proteins are commonly referred as Sm nuclear antigens due to their antigenic nature.Complement C3: A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.