Unit 2 - Innate Immune Barriers and Components

mechanical barriers

body expels pathogens → shedding skin, eyelashes, peeing, pooping,

chemical barriers consist of

antimicrobial and immunomodulatory peptides

first line defense mechansims

physical, mechanical, anatomical, chemical, genetic, microbial

first line defense

immune defenses before pathogen enters sterile tissue

hematopoietic stem cells generate

RBCs, platelets, leukocytes,

leukocytes subdivide into

myeloid and lymphoid

cells active at birth

all myeloid cells and NK cells (lymphoid)

phagocyte

engulfs and digests foreign particles and organisms

phagocytes divide into

professional and non professional

professional phagocyte cells

macrophage, neutrophils, dendritic cells, monocytes

neutrophil

first responder to infection; filled granules; phagocytoses

monocytes

circulates blood and enters tissue during infection; regulates inflammation via cytokine

monocytes differentiate to

macrophages and dendritic cells

macrophages promote

localized inflammation, immune and custodial role post infection

dendritic cells

innate immune cells, initiate adaptive immune response

eosinophil

performs frustrated phagocytosis, induce release of histamine by mast cells

eosinophils particularly attracted to

parasites coated in IgE Ab

frustrated phagocytosis

degranulate and release toxins around parasites to big to phagocytose

mast cells

in connective tissue, induce inflammation, ubiquitous response, early warning system

basphils

circulate in blood, induce inflammation, systemic response (food borne allergies)

NK cells

lymphocytes that lyse or induce apoptosis in target cell; only innate response lymphoid

complete blood count

measures RBCs, WBCs, platelets; aid in disease diagnosis

CBC-diff

measures specific WBCs

elevated CBC

indicates infection

depressed counts CBC

indicates immune exhaustion, suppression, failure