Phagocytosis Flashcards
Process of Phagocytosis
Initiation Chemotaxis Recognition Ingestion Digestion Excretion
Oxidative Burst/Respiratory burst through engulfment of cell by wbcs
Phagocytosis
Process which cells adhere to the vascular system as a result of damage and trauma which increases surface receptors
Initiation
Cell receptors involved in the Initiation stage
CR3
Laminin receptor
Leucyl-formyl-methionyl phenylalanine receptors
Dominant phagocytic complement receptor in humans
CR3
Most potent PMN chemotactic factor;
Leucyl-formyl-methionyl phenylalanine receptors
Process which cells move to the site of injury under influence of chemotaxins
Chemotaxis
Potent chemo-attractants
C5a
C3a
Impaired chemotaxis
Job Syndrome
Lab Tests in Chemotaxis
Boyden Chamber Assay
Migration through Agarose gel
Process which cells discriminate self and non-self component
Recognition
2 mechanisms of Recognition
Direct Recognition
Indirect Recognition
Direct Recognition
Via:
Recognizes:
Direct Recognition
Via: Primitive Pattern Recognition Receptors
Recognizes: Pathogen Associated Molecular Patterns (PAMPS) on microorganisms
Indirect Recognition
Via:
Recognizes:
Indirect Recognition
Via: Opsonization
Recognizes: Opsonins coating the microorganisms
Most common Opsonins
C3b, iC3, C4b, IgG
______ coats/marks the microorganisms to facilitate increase phagocytosis by easily identifying antigens
Opsonins
Opsonins attach to the ______ of the antigens
Epitope
Antigenic determinant
Epitope
Process of cell eating which forms projections/cytoplasm extends out in the microorganisms
Ingestion
Steps in Ingestion
Pseudopod formation
Phagosome formation
Phagolysosome formation
_________ is a phagosome fused with cytoplasmic granules
Phagolysosome
Ingestion is enhanced by:
Opsonins
Surfuctants
Ingestion is inhibited by capsulated bacteria: ____________, ____________, ____________.
H. influenzae
S. pneumoniae
N. miningitidis
Microorganism inside the cell or a vacoule
Phagosome
Refers to the killing of microorganism
Digestion/Destruction
Destructon
Once fused granules degranulates, digestive enzymes promotes killing or oxidative burst of the microorganism
Effective Killing of the Microorganisms
Peroxidases: H2O2, Superoxide anion, NADPH oxidases
Lysosomal contents
Lysozymes, Lactoferrins, Defensins
Defect in Lysosomal Enzyme Activity
Chediack Higashi Syndrome
Defect in NADPH oxidase activation
Chronic Granulomatous Disease
Tests for Digetsion
Nitrotetrazolium blue Test
Interpretation: NBT Test
Blue Color - __________
No Color - __________
Interpretation: NBT Test
Blue Color - NADPH Activation
No Color - No Activation
Process which antigen is excreted and undigested part (epitope) is presented to its surface to activate adaptive immunity
Exocytosis
