title: Rapid and simple immunophenotypic characterization of lymphocytes using a new test.
abstract: OBJECTIVE
  In this paper, we report our experience of lymphocyte phenotyping of a series of 108 consecutive samples using a simple flow cytometry test (Lymphogram). The kit consists of a combination of 5 different markers conjugated with three fluorochromes (CD8-FITC, CD19-FITC, CD56-PE, CD3-PE, CD4-PECy5) in the same tube. This allows identification of different T-cells, NK subpopulations and B lymphocytes.
  
  
  METHODS
  The samples were divided into three groups: samples with absolute lymphocytosis (> 5 x 10(9)/L) (n = 50), samples with relative lymphocytosis (> 50%) (n = 24) and other categories for which a lymphocyte immunophenotype was required (T-cell lymphoma and estimation of blood involvement in chronic lymphoproliferative disorders (CLPD) (n = 34). When CD19+ cells exceeded the normal range or there was a suspicion of CLPD without B-cell lymphopenia, clonality was investigated by means of light chain restriction analysis.
  
  
  RESULTS
  In the first group, 29 samples were abnormal (10 CLPD, 3 polyclonal B-cell lymphocytosis, 13 inversions of the CD4/CD8 ratio and 3 cases with CD4 lymphocytosis) and 21 samples were regarded as normal. In the second group 7 samples showed abnormalities (2 CLPD, 3 inverted CD4/CD8 ratios and 2 with a relative increase in CD4 cells). In one sample from the third group B-cell clonality without lymphocytosis was detected whereas in 18 samples a polyclonal pattern was observed. The presence of B-cell lymphopenia precluded further clonality study in 13 samples.
  
  
  CONCLUSIONS
  Lymphogram associated with clonality analysis is a rapid, easy and cheap method of assessing lymphocyte phenotypes in the majority of clinically relevant situations.
authors.affiliation: Departament d'Hematologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Bellido
authors.forename: E
authors.initials: E
authors.lastname: Rubiol
authors.forename: J
authors.initials: J
authors.lastname: Ubeda
authors.forename: C
authors.initials: C
authors.lastname: Estivill
authors.forename: O
authors.initials: O
authors.lastname: López
authors.forename: R
authors.initials: R
authors.lastname: Manteiga
authors.forename: J F
authors.initials: JF
authors.lastname: Nomdedéu
mesh_terms: D015703:Antigens, CD / Q000032:analysis; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D005069:Evaluation Studies as Topic; D005434:Flow Cytometry; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000032:analysis; D016130:Immunophenotyping / Q000379:methods*; D007694:Killer Cells, Natural / Q000145:classification; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology; D008218:Lymphocytosis / Q000097:blood; D008232:Lymphoproliferative Disorders / Q000097:blood
chemical_list: D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D000945:Antigens, Differentiation, T-Lymphocyte; D007147:Immunoglobulin Light Chains