Publications by authors named "Lot D de Witte"

Microglia, the immune cells of the brain, are increasingly implicated in neurodegenerative disorders through genetic studies. However, how genetic risk factors for these diseases are related to microglial gene expression, microglial function, and ultimately disease, is still largely unknown. Microglia change rapidly in response to alterations in their cellular environment, which is regulated through changes in transcriptional programs, which are yet poorly understood.

View Article and Find Full Text PDF

Introduction: Adaptations of the immune system throughout gestation have been proposed as important mechanisms regulating successful pregnancy. Dysregulation of the maternal immune system has been associated with adverse maternal and fetal outcomes. The design and interpretation of human biomarker studies require additional insights in the trajectories and drivers of peripheral immune markers.

View Article and Find Full Text PDF

Objective: Maternal immune activation has been proposed as a mechanism for adverse pregnancy outcomes, yet the mechanisms and effects of timing remain unclear. Immune disruption in early gestation may be particularly detrimental as this is an important period for placental development, which has been associated with the pathology of adverse obstetric outcomes. To increase our understanding of risk factors for adverse obstetric outcomes, we aim to investigate the association between multiple inflammatory and angiogenic markers during early pregnancy and adverse pregnancy outcomes in a large population-based cohort.

View Article and Find Full Text PDF

A proviral reservoir persists within the central nervous system (CNS) of people with HIV, but its characteristics remain poorly understood. Research has primarily focused on cerebrospinal fluid (CSF), as acquiring brain tissue is challenging. We examined size, cellular tropism, and infection-dynamics of the viral reservoir in post-mortem brain tissue from five individuals on and off antiretroviral therapy (ART) across three brain regions.

View Article and Find Full Text PDF

Neuroglia in the CNS, represented by astroglia, oligodendroglia, and microglia, are responsible for the homeostatic support and protection of the nervous tissue. Neuroglia are intimately involved in the pathogenesis of all neurologic diseases, and neuroglial changes to a large extent define the progression of these diseases and their neurologic outcome. In contrast to neurons, neuroglia are capable of mounting an evolutionary conserved response to pathology known as reactive gliosis.

View Article and Find Full Text PDF

Neuroglial cells serve as the master regulators of the central nervous system, making it imperative for glial development to be tightly regulated both spatially and temporally to ensure optimal brain function. In this chapter, we will discuss the origin and development of the three major glia cells such as astrocytes, oligodendrocytes, and microglia in the central nervous system. While much of our understanding of neuroglia development stems from studies using animal models, we will also explore recent insights into human glial development and potential differences from rodent models.

View Article and Find Full Text PDF

The nervous tissue is composed of neurons and neuroglia, which by working in a tightly coordinated manner, define the function of the nervous system. Neuroglia, defined as homeostatic and defensive cells of the nervous system, are highly heterogeneous in form and function and are endowed with a remarkable plasticity that allows life-long adaptation to environmental challenges. Neuroglia of the peripheral nervous system are represented by myelinating, nonmyelinating, perisynaptic, and cutaneous Schwann cells, satellite glia of sensory and sympathetic ganglia and enteric glia of the enteric nervous system.

View Article and Find Full Text PDF

Microglia, the innate immune cells of the central nervous system, have been genetically implicated in multiple neurodegenerative diseases. Mapping the genetics of gene expression in human microglia has identified several loci associated with disease-associated genetic variants in microglia-specific regulatory elements. However, identifying genetic effects on splicing is challenging because of the use of short sequencing reads.

View Article and Find Full Text PDF

Prenatal infections and activation of the maternal immune system have been proposed to contribute to causing neurodevelopmental disorders (NDDs), chronic conditions often linked to brain abnormalities. Microglia are the resident immune cells of the brain and play a key role in neurodevelopment. Disruption of microglial functions can lead to brain abnormalities and increase the risk of developing NDDs.

View Article and Find Full Text PDF

Background: Antibodies against the N-methyl-D-aspartate receptor (NMDAR) have been described in the serum of people with schizophrenia spectrum disorders (schizophrenia). However, the prevalence and clinical relevance of these antibodies in schizophrenia is unclear. This knowledge gap includes the possibility of such antibodies being associated with a distinct clinical profile, which in turn might warrant a distinct treatment approach.

View Article and Find Full Text PDF

New in vitro models provide an exciting opportunity to study live human microglia. Previously, a major limitation in understanding human microglia in health and disease has been their limited availability. Here, we provide an overview of methods to obtain human stem cell or blood monocyte-derived microglia-like cells that provide a nearly unlimited source of live human microglia for research.

View Article and Find Full Text PDF

Adaptations of the immune system throughout gestation have been proposed as important mechanisms regulating successful pregnancy. Dysregulation of the maternal immune system has been associated with adverse maternal and fetal outcomes. To translate findings from mechanistic preclinical studies to human pregnancies, studies of serum immune markers are the mainstay.

View Article and Find Full Text PDF

Prenatal infections and activation of the maternal immune system have been proposed to contribute to causing neurodevelopmental disorders (NDDs), chronic conditions often linked to brain abnormalities. Microglia are the resident immune cells of the brain and play a key role in neurodevelopment. Disruption of microglial functions can lead to brain abnormalities and increase the risk of developing NDDs.

View Article and Find Full Text PDF
Article Synopsis
  • HIV persists in the central nervous system (CNS) of people living with HIV, leading to cognitive impairments even with antiretroviral therapy (ART).
  • Researchers analyzed paired cerebrospinal fluid (CSF) and blood samples from 19 untreated adults, finding higher HIV RNA levels in plasma compared to CSF and mostly consistent coreceptor usage.
  • The study revealed that some viruses in the CNS can replicate in microglia (brain immune cells) as well as T-cells, suggesting that viral evolution may help the infection spread within the CNS, which needs further investigation.
View Article and Find Full Text PDF

Disturbances in T-cells, specifically the Th17/Treg balance, have been implicated in adverse pregnancy outcomes. We investigated these two T-cell populations following pre-pregnancy and pregnancy SARS-CoV-2 infection and COVID-19 vaccination in 351 participants from a pregnancy cohort in New York City (Generation C; 2020-2022). SARS-CoV-2 infection status was determined via laboratory or medical diagnosis and COVID-19 vaccination status via survey and electronic medical records data.

View Article and Find Full Text PDF

Schizophrenia is one of the most debilitating mental disorders, and its diagnosis and treatment present significant challenges. Several clinical trials have previously evaluated the effectiveness of simvastatin, a lipid-lowering medication, as a novel add-on treatment for schizophrenia. However, treatment effects varied highly between patients and over time.

View Article and Find Full Text PDF

Importance And Objective: The brain-penetrant tetracycline antibiotics, minocycline and doxycycline, have been proposed as potential candidate drugs for treatment of schizophrenia, based on preclinical studies and clinical trials. A potential long-term beneficial effect of these antibiotics for schizophrenia patients has not been investigated. This study was designed to determine if redemption of doxycycline prescription in schizophrenia is associated with decreased incidence of disability pension, a proxy for long-term functioning.

View Article and Find Full Text PDF

Numerous studies reported an increase of postpartum mood symptoms during the COVID-19 pandemic. Yet, the link between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and perinatal mental health is less well understood. We investigated the associations between prenatal SARS-CoV-2 infection and postpartum depressive and anxiety symptoms, including examinations of infection timing and pandemic timeline.

View Article and Find Full Text PDF

Microglia, the innate immune cells of the central nervous system, have been genetically implicated in multiple neurodegenerative diseases. We previously mapped the genetic regulation of gene expression and mRNA splicing in human microglia, identifying several loci where common genetic variants in microglia-specific regulatory elements explain disease risk loci identified by GWAS. However, identifying genetic effects on splicing has been challenging due to the use of short sequencing reads to identify causal isoforms.

View Article and Find Full Text PDF

Unlabelled: Microglia, the immune cells of the brain, are increasingly implicated in neurodegenerative disorders through genetic studies. However, how genetic risk factors for these diseases are related to microglial gene expression, microglial function, and ultimately disease, is still largely unknown. Microglia change rapidly in response to alterations in their cellular environment, which is regulated through changes in transcriptional programs, which are as yet poorly understood.

View Article and Find Full Text PDF

Cerebral organoids (CerOrgs) derived from human induced pluripotent stem cells (iPSCs) are a valuable tool to study human astrocytes and their interaction with neurons and microglia. The timeline of astrocyte development and maturation in this model is currently unknown and this limits the value and applicability of the model. Therefore, we generated CerOrgs from three healthy individuals and assessed astrocyte maturation after 5, 11, 19, and 37 weeks in culture.

View Article and Find Full Text PDF
Article Synopsis
  • A study investigated the impact of prenatal infections on the brain outcomes of adolescents using data from the Generation R Study, with a focus on 1094 mother-child pairs.
  • Findings indicated that higher prenatal infection scores were associated with reduced white matter volume and smaller volumes in certain brain regions, particularly the caudal anterior cingulate.
  • The researchers concluded that while there were potential brain areas of interest related to prenatal infections, there was no evidence of effects on overall brain morphology, white matter microstructure, or functional connectivity, suggesting a need for further research on severe infections.
View Article and Find Full Text PDF

Immune-related mechanisms have been suggested to be involved in schizophrenia. Various studies have shown changes in monocytes isolated from the blood of schizophrenia patients, including changes in monocyte numbers, as well as altered protein and transcript levels of important markers. However, validation of these findings and understanding how these results are related to immune-related changes in the brain and schizophrenia genetic risk factors, is limited.

View Article and Find Full Text PDF

Background: Doxycycline and minocycline are brain-penetrant tetracycline antibiotics, which recently gained interest because of their immunomodulatory and neuroprotective properties. Observational studies have suggested that exposure to these drugs may decrease the risk to develop schizophrenia, but results are inconsistent. The aim of this study was to investigate the potential association between doxycycline use and later onset of schizophrenia.

View Article and Find Full Text PDF

There is a consensus in the field that microglia play a prominent role in neurodevelopmental processes like synaptic pruning and neuronal network maturation. Thus, a current momentum of associating microglia deficits with neurodevelopmental disorders (NDDs) emerged. This concept is challenged by rodent studies and clinical data.

View Article and Find Full Text PDF