Phosphorylation of S409/410 of TDP-43 is a consistent feature in all sporadic and familial forms of TDP-43 proteinopathies.
Accumulation of hyperphosphorylated, ubiquitinated and N-terminally truncated TAR DNA-binding protein (TDP-43) is the pathological hallmark lesion in most familial and sporadic forms of FTLD-U and ALS, which can be subsumed as TDP-43 proteinopathies. In order to get more insight into the role of abnormal phosphorylation in the disease process, the identification of specific phosphorylation sites and the generation of phosphorylation-specific antibodies are mandatory. Here, we developed and characterized novel rat monoclonal antibodies (1D3 and 7A9) raised against phosphorylated S409/410 of TDP-43. These antibodies were used to study the presence of S409/410 phosphorylation by immunohistochemistry and biochemical analysis in a large series of 64 FTLD-U cases with or without motor neuron disease including familial cases with mutations in progranulin (n = 5), valosin-containing protein (n = 4) and linkage to chromosome 9p (n = 4), 18 ALS cases as well as other neurodegenerative diseases with concomitant TDP-43 pathology (n = 5). Our data demonstrate that phosphorylation of S409/410 of TDP-43 is a highly consistent feature in pathologic inclusions in the whole spectrum of sporadic and familial forms of TDP-43 proteinopathies. Physiological nuclear TDP-43 was not detectable with these mAbs by immunohistochemistry and by immunoblot analyses. While the accumulation of phosphorylated C-terminal fragments was a robust finding in the cortical brain regions of FTLD-U and ALS, usually being much more abundant than the phosphorylated full-length TDP-43 band, spinal cord samples revealed a predominance of full-length TDP-43 over C-terminal fragments. This argues for a distinct TDP-43 species composition in inclusions in cortical versus spinal cord cells. Overall, these mAbs are powerful tools for the highly specific detection of disease-associated abnormal TDP-43 species and will be extremely useful for the neuropathological routine diagnostics of TDP-43 proteinopathies and for the investigation of emerging cellular and animal models for TDP-43 proteinopathies.
Neumann
Manuela
M
Institute of Neuropathology, University Hospital of Zürich, Schmelzbergstr. 12, 8091 Zurich, Switzerland. manuela.neumann@usz.ch
Kwong
Linda K
LK
Lee
Edward B
EB
Kremmer
Elisabeth
E
Flatley
Andrew
A
Xu
Yan
Y
Forman
Mark S
MS
Troost
Dirk
D
Kretzschmar
Hans A
HA
Trojanowski
John Q
JQ
Lee
Virginia M-Y
VM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D004268:DNA-Binding Proteins / Q000276:immunology / Q000378:metabolism*; D003704:Dementia / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000150:complications / Q000378:metabolism; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D010766:Phosphorylation; D051381:Rats; D013116:Spinal Cord / Q000378:metabolism
D000911:Antibodies, Monoclonal; D004268:DNA-Binding Proteins