KEY POINTS INFLAMMATION CELLS

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1 THE IMMUNE RESPONSE IN VARIOUS TISSUES HYPERSENSITIVE & AUTOIMMUNE RESPONSES KEY POINTS The immune system has two responses, cell mediated and humoral, Cell mediated involves T lymphocytes Humoral mediated involves antibodies The immune system has memory and can immediately respond to a recognized antigen Inflammation is acute, immunity is chronic but they work hand in hand Stem cells in bone marrow produce inflammation and immunity cells and send them to body tissues for later use PMN blood Stem cell blood Monocyte Macrophage In tissue Thymus T Lymphocyte Lymph tissue B Lymphocyte INFLAMMATION CELLS PMN s (neutrophils) respond first to an antigen Monocytes become macrophages when they leave the blood and enter the tissue Macrophages phagocytize cells, byproducts Macrophages are present in both inflammation and immunity 1

2 Thymus lymphocytes are major player in cell mediated response Helper T s join with a B lymphocyte and form a plasma cell that manufacturers antibodies (immunoglobulins) Killer T s destroy antigens allowing macrophages to phagocytize them Killer T Macrophage IgD (triggers immunity?) Helper T B lymphocyte Plasma cell IgA (found in saliva) Antigen Memory T s recognize previous antigens and respond quickly IgE (Mast cell activator) IgM (activates complement) Plasma cell makes 5 immunoglobulins IgG (80% of antibodies) GAMED Immunoglobulins attach to antigens to form an antigen/antibody complex HYPERSENSITIVE RESPONSES Immunoglobulin Macrophage If the immune response overreacts to an antigen, a hypersensitive response occurs. We sometimes call it an allergy. There are four types of hypersensitive responses, Type I, II, III, and IV. Macrophages phagocytize entire complex 2

3 TYPE I RESPONSE - ANAPHYLAXIS In response to an memorized antigen, a large amount of IgE is released TYPE I RESPONSE - ANAPHYLAXIS Histamine causes blood vessels to dilate and bronchioles to constrict causing erythema, hypotension, dyspnea HISTAMINE Mast cell IgE HISTAMINE IgE Mast cell IgE Mast cell IgE Mast cell HISTAMINE HISTAMINE IgE causes mast cells to produce a large amount of histamine Anaphylactic shock (can lead to death) Angioedema TYPE II RESPONSE- CYTOTOXIC Antigen attaches to certain cells in the body, Antibodies attach to the antigen and the cell, Both the antigen and the cell are destroyed by the immune system, Rh incompatibility is an example TYPE III RESPONSE-IMMUNE COMPLEX Antigen/antibody complexes leave blood, attach to tissue Complex as well as tissue is destroyed by immune system This response often seen in autoimmune diseases and periodontal disease 3

4 TYPE IV RESPONSE - DELAYED TYPE IV RESPONSE - DELAYED T lymphocytes respond to memorized invading antigen at skin surface, Useful for such things as skin test for TB (PPD test) Causes contact dermatitis, transplant rejections, May play a role in periodontal disease Latex allergy Response to local anesthetic Response to denture acrylic IMMUNOLOGIC CONDITIONS Lesions that occur in and around the oral cavity that have unknown etiology but the immune system is involved Conditions include Apthous ulcers Lichen planus Erythema Multiforme Reiter s Syndrome Langerhans Cell Disease APTHOUS ULCERS Commonly called canker sores T lymphocytes associated with lesion but etiology unsure Occur on nonkeratinized, movable tissue (Recurrent herpes occurs on keratinized) Occur as minor, major (Sutton s disease) or herpetiform Painful, but self limiting Characteristic oval lesion, white fibrin in middle surrounded by erythema halo 4

5 APTHOUS ULCERS LICHEN PLANUS A suspected autoimmune disease because of the presence of T lymphocytes Characterized by lacy marking called Wickham s striae The erosive form is described as desquamative gingivitis, the epithelium sloughs Minor Major Herpetiform Patients with lichen planus may have higher risk for squamous cell carcinoma No treatment for the mild form, corticosteroids for erosive Treatment is palliative, topical steroids may help LICHEN PLANUS REITER S SYNDROME Involves a triad of arthritis, urethritis, and conjunctivitis Oral lesions resemble apthous ulcers Lichen planus with typical Wickham s stria Erosive form 5

6 LANGERHAN S CELL DISEASE Involves three diseases with proliferating Langerhan s cell, a type of macrophage Letterer Siwe is acute type of lymphoma in children and is fatal Hand-Schuller-Christian is in children under 5, causes advanced periodontal disease eosinophilic granuloma causes radiolucencies that may resemble periapical abscess or periodontal disease ERYTHEMA MULTIFORME Noted for it s bullseye lesions on hands, feet May be an allergic response but not definite Most serious form is Stevens-Johnson s syndrome which involves eyes, lips, genitals ERYTHEMA MULTIFORME AUTOIMMUNE DISEASES Bullseyes Stevens-Johnson syndrome The immune system treats certain body cells an antigens, destroys them Autoimmune diseases affecting the oral cavity include Lupus erythematosus Sjögren s syndrome Pemphigus vulgaris Benign mucous mdmbrand pehphigoid Behçet s syndrome Pernicious anemia (not discussed) 6

7 LUPUS ERYTHEMATOSUS Autoimmune disease involving a type III hypersensitive response affects mainly women Butterfly shaped rash over nose is common Oral lesions are common Can be mild (discoid) or life threatening MUCOUS MEMBRANE PEMPHIGOID Also called cicatricial pemphigoid because it leaves scars Body rejects basement membrane, tissue sloughs Described as desquamative gingivitis When tissue gently rubbed, a bulla forms, called Nikolsky s sign PEMPHIGUS VULGARIS Similar to mucous membrane pemphigoid but more severe. Immunofluorescence, a lab test, shows antibodies in basement membrane Acantholysis describes the sloughing of tissue SJÖGREN S SYNDROME Autoimmune disease characterized by xerostomia, xerophthalmia Patients often have arthritis, another autoimmune disease Tongue appears to lose papillae, Patient susceptible to caries, periodontal disease 7

8 BEHÇET S SYNDROME Triad of symptoms including oral lesions, genital lesions, and ocular inflammation Oral lesions resemble apthous ulcers 8