Host Defense Against Oral Infections Flashcards

Question

Principal events of inflammation

Answer 1

* Local phagocytes release of inflammatory * Cytokines: TNF-alpha, IL-1 * Chmokines: MIP MCP * Cytokines * recruit and activate phagocytes * stimulate cell response * Vasodilation inc blood flow * Increased cepillary permeability * Leukocytes migrate to reach site of infection * PMN first * Monocytes and lymphocytes come later * Periodontitis is inflammation based infection

Answer 2

Gingival crevice and 1/3 of tooth crown is covered with GCF Gingival Crevicular Fluid contains IgG IgM IgA Salivary Ab is predominantly sIgA Antibody can be locally made paticularly in inflamed gingivae

Answer 3

Monomer Makes up for a lot of AB in serum Crosses placenta Activates complement Major opsonizing AB Found in GCF to protect gum and crown

Answer 4

Pentamer First antibody generated against any antigen Predominant antibody produced by fetus Antibody for carb antigens (ABO groups) GCF contains IgM to protect gum and crown

Answer 5

* 2 forms * In serum as monomer * Secretions as dimer (saliva) sIgA * lines oral mucosa surfaces and protects from infection * interferes with adhesion molecules of pathogen * Opsonize pathogens at mucosal surface to prevent attachment * Confers mucosal immunity * Immune Exclusion-sIgA can differentiate which bacteria can provide a commensal or pathogenic *

Answer 6

* Mediates humoral mucosal immunity * Structure: polymeric, made locally by plasma cells in mucosal epithelium * IgA is the most abundantlly synthesized antibody * 2 subclasses IgA1 and IgA2 * In plasma IgA1 dominates * in saliva they are equal * IgA1 Ab directed against protein antigens * IgA2 Ab is against polysaccharide antigens * sIgA is part of enamel pellicle and good at agglutinating microbes

Answer 7

* Mucosal epithelium- physical barrier, first line of defense against invasion * GI & Respiratory mucosa colonized by lymphocytes and APC, respond ton Ags * GI- lymphocytes are w/i epithelial layer, lamina propria and Peryers Patch * each with unique phenotype and function * Intraepithelial lymphocytes are usually CD8 T cells * Ag stimuli at 1 site elicits an antibody response that is restricted to MALT * Immune response to oral AGs differ fundamentally from responses encountered at other sites

Answer 8

* Mucosal surfaces continously flushed by exocrine secretions * DC sample Ags btw epithelial cells * Responds to harmful organisms * regulates influx of immune cells * Prevents inflammatory tissue destruction * Alterations in the normal balance of flora can cause inappropriate immune responses * Commensal bacteria then become surrogate pathogens and stimulate chronic inflammatory response

Answer 9

* GCF glushes gingival margin-oral cavity area, a vulnerable area * Plaque at gingival margin results in acute inflammation * Increases the flow of GCFto bring components to site * Healthy: dynamic equilibrium of endogenous oral microbes and host antimicrobial factors *

Answer 10

* Ecological imbalance btw resident microbes and host immune response * Dental Caries * Frequently eating fermentable barbs lead to selective advatage to higly acidogenic bacteria (lactobacilli, S. mutans) * Colonize on sugar matrix * Lead to biofilm or plaque

Answer 11

* M cells have specialized microfolds to take up Ag * Bring Ab to Intraepithelial DC * Initiate IgA response, that dominate mucosal surface * sIgA first line of defense * Oral immunization with protein Ags induce tolerance * CD4 T cells important in generation of oral mucosal tolerance *

Answer 12

* Mucins, defensins, trefoil, pellicle, lysozyme and NO * Non-specifically shoeld mucosal from microbial damage

Answer 13

* Intra-epithelial lymphocytes and Langerhans Cells * Cellular barrier to bacteria/ag * CD4 T cells- * Secretion of cytokines * sIgA- * Prevent microbe adhesion and metabolism * IgG, IgA, IgM * Prevent adhesion * Opsonization * Complement activation

Host Defense Against Oral Infections Flashcards

(37 cards)