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J C Cole

Publications and source records attributed to J C Cole.

5 recordsLinked to original sources

Abnormal CD45R expression in patients with common variable immunodeficiency and X-linked agammaglobulinaemia.

This study has investigated the patterns of membrane 2H4 (CD45RA) and UCHL1 (CD45RO) expression by CD4+ and CD8+ lymphocyte subpopulations in 10 adults and seven children with common variable immunodeficiency (CVI) and X-linked hypogammaglobulinaemia (XLA). Of the 10 adults (CVI, n = 8; XLA, n = 2), only one with a diagnosis of CVI showed normal CD45R expression. For the remaining seven adult CVI patients the abnormal CD45R profiles were primarily associated with CD4+ lymphocytes in three and CD8+ lymphocytes in four. Specific increases in CD45RA- CD45RO+ fractions were found in four CVI patients and in all of these there was a concomitant reduction in circulating CD19+ B-cell numbers. Two of the CVI cases were identical twin sisters and both had the same CD45R abnormality. The two adults with XLA also showed abnormal CD45R expression (increased CD45RA+ CD45RO- components) but of particular note, in view of the fact that these were brothers, one was associated with the CD4+ subpopulation and the other with the CD8+ fraction. Similar analyses for the paediatric group revealed, in distinct contrast to the adult patients, no significant abnormalities of CD45R expression suggesting that these defects may not become apparent until a later age. Further investigations of in vitro lymphocyte proliferation (PHA and PWM) in the eight adults with CVI showed a significant correlation between abnormal responses and disordered CD45R expression. It is proposed that these abnormal patterns of CD45R expression by lymphocyte subpopulations in CVI and XLA may be of fundamental importance with respect to the pathogenesis of these particular immunodeficiencies.

Adolescent

Variant CD45R expression with autosomal dominant inheritance affects both helper/inducer (CD4+) and suppressor/cytotoxic (CD8+) T cell populations.

The differential expression of various membrane CD45R isoforms by normal lymphocyte populations is known to be closely associated with distinct immunoregulatory functions. Abnormal patterns of CD45R expression have been reported in patients with common variable immunodeficiency and HIV infection, and recent evidence has suggested the possibility that one type of variant CD45R expression may be inheritable. By multiple colour flow cytometry, we studied the immunological characteristics of CD4+ helper/inducer and CD8+ suppressor/cytotoxic T cells in a family with variant CD45R expression over three generations. This variant pattern of CD45R expression was shown to affect both CD4+ and CD8+ lymphocyte populations in individual family members and was immunologically characterized by a failure of the normal reciprocal expression of the CD45RA and CD45RO isoforms. Family studies also revealed that this trait had an autosomal dominant mode of inheritance and, in the heterozygous state, appeared not to be associated with major clinical abnormalities. The different isoforms of CD45 show distinct patterns of expression during lymphocyte ontogeny and activation, and these patterns appear to closely reflect function. Despite their diverse immunological roles, our finding that both CD4+ and CD8+ T cells in affected family members showed the same defect suggests a common regulatory mechanism(s) for both these lymphocyte populations. The recognition of this abnormality, particularly in homozygous individuals, will be of great importance in understanding the role of these molecules in immune function and disease.

Adolescent