title: Serum levels of CD8 antigen in childhood lymphoid malignancies: a possible indicator of increased suppressor cell activity in poor-risk patients.
abstract: Serum concentrations of CD8 antigen were measured at diagnosis with an enzyme-linked immunoassay in children with acute lymphoblastic leukemia (n = 344) or non-Hodgkin's lymphoma (n = 65). All patients had detectable levels of the serum antigen, which in its soluble nonreduced form appeared to be a 52-Kd homodimer as compared with the 66-Kd surface membrane component on most thymocytes and on a subset of functionally distinct T cells (suppressor/cytotoxic). Increased serum levels of CD8 in leukemia patients were significantly related to recognized high-risk prognostic features: high leukocyte count, large liver and spleen size, high serum lactic dehydrogenase level, T-cell immunophenotype, presence of a mediastinal mass, pseudodiploid karyotype, DNA index less than 1.16, and chromosomal translocation. Children with serum CD8 levels greater than or equal to 450 U/mL were more likely to fail treatment than were those with lower levels (P = .002), even in the group with non-T-cell leukemia (P = .003). In a multivariate analysis, serum CD8 antigen contributed independent prognostic information beyond that conveyed by age, leukocyte count, and race (P = .02). High serum CD8 antigen levels also correlated with advanced stages of disease in children with non-Hodgkin's lymphoma or B-cell leukemia. Children with higher serum CD8 antigen levels (greater than or equal to 700 U/mL) had a poorer treatment outcome (P = .003), even after results were adjusted for disease stage and serum lactic dehydrogenase level (P = .05). Measurement of serum levels of CD8 antigen not only has important prognostic value in childhood lymphoid malignancies but also could be useful in assessing the immunoregulatory role of T cells in patients with cancer.
authors.affiliation: Department of Hematology-Oncology, St Jude Children's Research Hospital, Memphis, TN 38101.
authors.forename: C H
authors.initials: CH
authors.lastname: Pui
authors.forename: S H
authors.initials: SH
authors.lastname: Ip
authors.forename: R K
authors.initials: RK
authors.lastname: Dodge
authors.forename: S
authors.initials: S
authors.lastname: Carrabis
authors.forename: M
authors.initials: M
authors.lastname: Brown
authors.forename: W M
authors.initials: WM
authors.lastname: Crist
authors.forename: C W
authors.initials: CW
authors.lastname: Berard
authors.forename: P
authors.initials: P
authors.lastname: Kung
authors.forename: G V
authors.initials: GV
authors.lastname: Dahl
authors.forename: S B
authors.initials: SB
authors.lastname: Murphy
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis* / Q000276:immunology; D000954:Antigens, Surface / Q000032:analysis / Q000276:immunology; D014408:Biomarkers, Tumor / Q000097:blood* / Q000276:immunology; D016827:CD8 Antigens; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007945:Leukemia, Lymphoid / Q000097:blood* / Q000188:drug therapy / Q000276:immunology; D008228:Lymphoma, Non-Hodgkin / Q000097:blood* / Q000188:drug therapy / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011379:Prognosis; D012307:Risk Factors; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D014408:Biomarkers, Tumor; D016827:CD8 Antigens