Immunophenotypic and DNA genotypic analysis of T-cell and NK-cell subpopulations in patients with B-cell chronic lymphocytic leukaemia (B-CLL).
Absolute numbers and distributions of peripheral blood T-cells and NK cells were immunophenotypically determined in 21 patients with B-CLL and compared with those obtained from a series of 13 elderly normal controls with an age range of 60-87 years. For absolute CD3+, CD4+ and CD8+ T-cell, and CD16+ NK subpopulation numbers, there were no consistent differences between the normal and B-CLL groups although some individual patient variation was seen. Immunophenotypic analyses did however reveal that CD3+ T-cells in almost half (10/21) of the B-CLL patients were Ia+ (defined as > 20% positive cells), compared to 0/13 of the elderly control group (p < 0.001), and that the proportions of CD4+ and CD8+ cells expressing membrane CD45RO were significantly increased compared to the control group. Subdivision of the B-CLL cases into those with low (< 20%) and high (> 20%) proportions of CD3+ T-cells co-expressing Ia further showed that CD45RO expression by CD4+ fractions was particularly prominent in the Ia+ subgroup, and that the relative increase of CD4+CD45RO+ cells was primarily a consequence of decreased absolute numbers of CD4+CD45RA+ lymphocytes. This study also examined extracted DNA from enriched CD3+ T-cell fractions (obtained by immunomagnetic bead selection in 9 of the B-CLL cases) by PCR analysis with two primers for the T-cell gamma gene locus. With the V gamma C (consensus) primer, 8/9 cases were polyclonal and the remaining case was oligoclonal. For comparison, 7/9 CD3+ fractions were oligoclonal with the V gamma 9 primer with the other two cases being polyclonal. No monoclonal CD3+ components were found. It is suggested that the observed increased Ia expression by CD3+ cells and the predominance of CD4+ cells expressing membrane CD45RO in patients with B-CLL may be of potential relevance to understanding the pathogenesis and patterns of disease progression.
Frolova
E A
EA
Haematological Malignancy Diagnostic Service, Leeds General Infirmary, England.
Richards
S J
SJ
Jones
R A
RA
Rawstron
A
A
Master
P S
PS
Teasdale
J
J
Short
M
M
Jack
A S
AS
Scott
C S
CS
D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000235:genetics; D001483:Base Sequence; D005260:Female; D015870:Gene Expression; D015973:Gene Expression Regulation, Leukemic; D005838:Genotype; D006684:HLA-DR Antigens / Q000235:genetics; D006801:Humans; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000502:physiology; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D017493:Leukocyte Common Antigens / Q000235:genetics; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000502:physiology*; D013601:T-Lymphocytes / Q000502:physiology
D015703:Antigens, CD; D006684:HLA-DR Antigens; D017493:Leukocyte Common Antigens