Brain Flashcards
name the 3 characteristics of the neuro-immune system
- healthy humans have 150.000 T lymphocytes in the CSF
- T cells patrol the CSF or PVS for pathogens
- memory CD4+ T cells return to the blood stream via lymphatic vessels in the meningeal spaces and the deep cervical lymph nodes
what is the definition of meningitis?
inflammation of the meninges
what is the definition of cerebritis?
inflammation of brain tissue (encephalitis)
what is sepsis?
proliferation of bacteria in the bloodstream
name 3 bacterial inflammations affecting the CNS
- tuberculosis
- syphilis
- lyme disease
name 3 viral inflammations affecting the CNS
- herpes simplex type 1
- rabies
- poliomyelitis
what is the CNS?
everything inside the skull and spine but also the optic nerve
what is the definition of immune privilege?
the permissiveness and proneness of a tissue or anatomical site to develop and sustain immune activity
how does a T cell move from lumen to CNS?
blood-brain barrier –> perivascular space –> glia limitans
what is the natural habitat of CNS T cells?
the perivascular space, reactivation in PVS is needed to enter parenchyma
how is inflammation controlled in the brain?
- limited capacity of parenchymal APCs to provide effective activation
- high levels of anti-inflammatory molecules (CD200)
- requirement of T cell re-activation after crossing the BBB
- entry of inflammatory cells is tightly regulated by BBB
name the 4 major CNS cell types
- neurons
- astrocytes
- oligodendrocytes
- microglia
name 4 exogenous causes of chronic inflammation in the CNS
- herpes simplex virus
- measles virus
- cytomegalovirus (CMV)
- Theiler’s Murine encephalomyelitis virus (TVEM)
which lymphocytes infiltrate the CNS during early, middle and late chronic inflammation?
early; macrophages
middle; expansion of T and B cells
late; mainly CD8 T cells
what is and which cells play a role in neuromyelitis optica?
demyelination of the optic nerve and the spinal cord, AQP4 and MOG specific IgG