Microglia activation is recognized as the hallmark of neuroinflammation. However, the activation profile and phenotype changes of microglia during the process of retinal degeneration are poorly understood. This study aimed to elucidate the time-spatial pattern of microglia distribution and characterize the polarized phenotype of activated microglia during retinal neuroinflammation and degenerat...

Activated forms of microglia were ultrastructurally evaluated in three neurological diseases of different aetiology (subacute sclerosing panencephalitis--SSPE, Wilson's disease and Alzheimer's disease). The occurrence of activated rod, ramified and amoeboid microglia was found in the investigated diseases. The widest ultrastructural variability of microglia was in SSPE, including the presence o...

Microglia are key players in the central nervous system in health and disease. Much pioneering research on microglia function has been carried out in vivo with the use of genetic animal models. However, to fully understand the role of microglia in neurological and psychiatric disorders, it is crucial to study primary human microglia from brain donors. We have developed a rapid procedure for the...

Brain microglial morphology relates to function, with ramified microglia surveying the micro-environment and amoeboid microglia engulfing debris. One subgroup of microglia, rod microglia, have been observed in a number of pathological conditions, however neither a function nor specific morphology has been defined. Historically, rod microglia have been described intermittently as cells with a sa...

Microglia are the primary immune cell in the brain and are postulated to play important roles outside of immunity. Administration of the dual colony-stimulating factor 1 receptor (CSF1R)/c-Kit kinase inhibitor, PLX3397, to adult mice results in the elimination of ~99% of microglia, which remain eliminated for as long as treatment continues. Upon removal of the inhibitor, microglia rapidly repop...

Persistent cognitive and behavioral symptoms that characterize many mental health disorders arise from impaired neuroplasticity in several key corticolimbic brain regions. Recent evidence suggests that reciprocal neuron-microglia interactions shape neuroplasticity during physiological conditions, implicating microglia in the neurobiology of mental health disorders. Neuron-microglia interactions...

One long standing aspect of microglia biology was never questioned; their involvement in brain disease. Based on morphological changes (retracted processes and amoeboid shape) that inevitably occur in these cells in case of damage in the central nervous system, microglia in the diseased brain were called "activated." Because "activated" microglia were always found in direct neighborhood to dead...

Cellular localization of platelet-activating factor (PAF) receptor in the rat brain was determined by (1) in situ hybridization, (2) Northern blot analysis in primary cell cultures of neurons, microglia, astrocytes, and fibroblasts, and (3) Ca2+ imaging in hippocampal culture. In situ hybridization revealed that the PAF receptor mRNA is expressed intensely in microglia and moderately in neurons...

This special issue describes exciting papers contributed to the International Journal of Alzheimer's Disease issue on microglia in Alzheimer's disease (AD). It has been well recognized that neuroinflammation is an early event in the pathogenesis of AD, in which microglia is a major player. A core theme of the articles presented in this special issue is the dichotomous role played by the microgl...

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS). Microglia are the resident innate immune cells in the CNS; they play an important role in the processes of demyelination and remyelination in MS. Microglia can function as antigen-presenting cells and phagocytes. In the past, microglia were considered to be the same cell type as macrophages, and researchers ha...