T-cell receptor analysis in anti-Hu associated paraneoplastic encephalomyelitis.
OBJECTIVE
To analyze the T-cell receptor (TCR) repertoire in the inflammatory infiltrates of the nervous system and tumor of patients with anti-Hu associated paraneoplastic encephalomyelitis and sensory neuronopathy (PEM/SN).


BACKGROUND
In PEM/SN, the pathogenic role of the infiltrating T cells is speculative. TCR analysis may establish whether these lymphocytes are attracted nonspecifically by a proinflammatory environment or are driven by a specific antigen or superantigen.


METHODS
We examined frozen tissues of seven patients with PEM/SN using immunohistochemical and PCR analysis. Of 62 tissue blocks from seven patients, 19 blocks from five patients had >100 CD3+ cells per section infiltrating the nervous system or tumor. These infiltrates allowed screening of the TCR Vbeta family repertoire using a panel of 18 antibodies that recognize family-specific regions of most TCR Vbeta families against which antibodies have been generated. To distinguish between antigen-driven clonal and superantigen-driven family expansion, we extracted RNA from frozen tissue and performed reverse transcriptase (RT)-PCR analysis followed by subcloning and sequencing of the antigen-specific CDR3 region of the TCR Vbeta chain.


RESULTS
All five patients showed a limited Vbeta repertoire. An overrepresentation (>10% of total CD3+) of certain Vbeta families was identified in three patients (as high as 45% of total CD3+), which consisted mainly of CD8 + cells. CDR3 sequences obtained from one patient revealed an in situ expansion of two clones in the amygdala (one at a frequency of 57%) and four clones in the tumor.


CONCLUSIONS
These findings suggest that an antigen-driven oligoclonal cytotoxic T-cell response plays a role in the pathogenesis of anti-Hu associated PEM/SN.
Voltz
R
R
Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
Dalmau
J
J
Posner
J B
JB
Rosenfeld
M R
MR
D000368:Aged; D000369:Aged, 80 and over; D000679:Amygdala / Q000276:immunology; D001932:Brain Neoplasms / Q000150:complications / Q000276:immunology*; D017252:CD3 Complex / Q000032:analysis; D018288:Carcinoma, Small Cell / Q000150:complications / Q000276:immunology; D002529:Cerebellar Nuclei / Q000276:immunology; D004273:DNA, Neoplasm / Q000032:analysis; D051959:ELAV Proteins; D004679:Encephalomyelitis / Q000150:complications / Q000276:immunology*; D005260:Female; D005727:Ganglia, Spinal / Q000276:immunology; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins; D009847:Olivary Nucleus / Q000276:immunology; D010257:Paraneoplastic Syndromes / Q000150:complications / Q000276:immunology*; D016601:RNA-Binding Proteins / Q000032:analysis* / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013602:T-Lymphocytes, Cytotoxic / Q000737:chemistry / Q000276:immunology
D017252:CD3 Complex; D004273:DNA, Neoplasm; D051959:ELAV Proteins; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; D016693:Receptors, Antigen, T-Cell, alpha-beta