 |
The Journal of Neuroscience, November 1, 2006, 26(44):11413-11422; doi:10.1523/JNEUROSCI.3340-06.2006
Previous Article | Next Article 
Neurobiology of Disease
Fusion of Microglia with Pyramidal Neurons after Retroviral Infection
James B. Ackman,
Faez Siddiqi,
Randall S. Walikonis, and
Joseph J. LoTurco
Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut 06269
Correspondence should be addressed to Joe LoTurco, Department of Physiology and Neurobiology, Box U-3156, University of Connecticut, Storrs, CT 06269. Email: loturco{at}uconn.edu
The neurogenic potential of the postnatal neocortex has not been tested previously with a combination of both retroviral and bromodeoxyuridine (BrdU) labeling. Here we report that injections of enhanced green fluorescent protein (eGFP) retrovirus into 134 postnatal rats resulted in GFP labeling of 642 pyramidal neurons in neocortex. GFP-labeled neocortical pyramidal neurons, however, unlike GFP-labeled glia, did not incorporate BrdU. Closer inspection of retrovirally labeled neurons revealed microglia fused to the apical dendrites of labeled pyramidal neurons. Retroviral infection of mixed cultures of cortical neurons and glia confirmed the presence of specific neuronalmicroglial fusions. Microglia did not fuse to other glial cell types, and cultures not treated with retrovirus lacked microglialneuronal fusion. Furthermore, activation of microglia by lipopolysaccharide greatly increased the virally induced fusion of microglia to neurons in culture. These results indicate a novel form of specific cell fusion between neuronal dendrites and microglia and further illustrate the need for caution when interpreting evidence for neuronogenesis in the postnatal brain.
Key words: cerebral cortex; neurogenesis; macrophage; inflammation; virus; bromodeoxyuridine; rat; pyramidal cell; dendrite; phagocytosis; cell fusion
Received Aug. 2, 2006;
revised Sept. 14, 2006;
accepted Sept. 17, 2006.
Correspondence should be addressed to Joe LoTurco, Department of Physiology and Neurobiology, Box U-3156, University of Connecticut, Storrs, CT 06269. Email: loturco{at}uconn.edu
Related articles in J. Neurosci.:
- This Week in The Journal
J. Neurosci. 2006 26: i.
[Full Text]
- Glowing Green Pyramids: A False Positive for Neocortical Neurogenesis Reveals a Novel NeuronalMicroglial Fusion in the Postnatal Brain
- Joshua J. Breunig and Jon I. Arellano
J. Neurosci. 2007 27: 1507-1508.
[Full Text]
This article has been cited by other articles:

|
 |

|
 |
 
F. Guo, J. Ma, E. McCauley, P. Bannerman, and D. Pleasure
Early Postnatal Proteolipid Promoter-Expressing Progenitors Produce Multilineage Cells In Vivo
J. Neurosci.,
June 3, 2009;
29(22):
7256 - 7270.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. Berninger, M. R. Costa, U. Koch, T. Schroeder, B. Sutor, B. Grothe, and M. Gotz
Functional Properties of Neurons Derived from In Vitro Reprogrammed Postnatal Astroglia
J. Neurosci.,
August 8, 2007;
27(32):
8654 - 8664.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Walter, B. L. Murphy, R. Y. K. Pun, A. L. Spieles-Engemann, and S. C. Danzer
Pilocarpine-Induced Seizures Cause Selective Time-Dependent Changes to Adult-Generated Hippocampal Dentate Granule Cells
J. Neurosci.,
July 11, 2007;
27(28):
7541 - 7552.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. J. Breunig and J. I. Arellano
Glowing Green Pyramids: A False Positive for Neocortical Neurogenesis Reveals a Novel Neuronal-Microglial Fusion in the Postnatal Brain
J. Neurosci.,
February 14, 2007;
27(7):
1507 - 1508.
[Full Text]
[PDF]
|
 |
|
|

|