Characterization of the T cell receptor repertoire of neonatal T cells by RT-PCR and single strand conformation polymorphism analysis.
We have analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) the individual non-germ line configurations of the T cell receptor (TCR) Vbeta chains expressed by T cells from eight individual cord blood specimens. cDNA from each cord blood was amplified using a common primer coupled with a primer specific for each of 22 variable elements of the Vbeta chain family and the amplified fragments were separated under high resolution conditions. With cDNA from adult blood (as a control), all of the TCR chains were amplified as a smear consistent with the extensive polyclonality of adult T cells. In contrast, a heterogeneous pattern of amplification was observed with cDNAs from cord blood: only 26.7+/-21.9% of the 22 Vbeta chains analyzed were amplified as a smear. The majority of them were amplified as a discrete number of bands (up to 10) (in 68.2 +/-18.7% of samples) and some of them as a single fragment (4.0+/-7.8%). Only one of the eight samples analyzed expressed the majority (72.7%) of its Vbeta chains as a smear, consistent with an adult-like TCR repertoire. In conclusion, cord blood expressed, on average, a less complex TCR repertoire than adult blood.
Laboratory of Cell Biology, Istituto Superiore di Sanità, Rome, Italy.
E
E
Alfani
A R
AR
Migliaccio
M
M
Sanchez
A M
AM
Passarelli
G
G
Migliaccio
D000328:Adult; D015703:Antigens, CD / Q000097:blood; D005312:Fetal Blood / Q000166:cytology; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D019674:Genes, T-Cell Receptor beta; D006801:Humans; D016130:Immunophenotyping; D007231:Infant, Newborn; D011948:Receptors, Antigen, T-Cell / Q000097:blood / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013601:T-Lymphocytes / Q000276:immunology*
D015703:Antigens, CD; D011948:Receptors, Antigen, T-Cell