Selective antipolysaccharide antibody deficiency associated with peripheral blood CD5+ B-cell predominance.
BACKGROUND
Primary humoral deficiencies vary from complete absence of B cells and/or serum immunoglobulin to lacunar deficits involving specific antibody responses to polysaccharides.


OBJECTIVE
We compared the B-cell CD5 expression in patients with selective antipolysaccharide antibody deficiencies (SPADs), common variable immunodeficiency (CVID), and IgG subclass deficiency and in normal control subjects.


METHODS
Five patient populations were evaluated: (1) patients with severe SPAD (no protective serologic postvaccine response to any of 12 polysaccharide antigens tested); (2) patients with intermediate SPAD (diminished response to polysaccharide antigens and adequate response to 1 to 3 of 12 serotypes tested); (3) patients with IgG subclass deficiency; (4) patients with CVID; and (5) age-matched control subjects. Blood was collected from all patients and evaluated by using flow cytometry. Results were compared by using the Student t test.


RESULTS
Patients with severe SPAD deficiencies had a marked predominance of CD5+ B cells in the peripheral blood (93% to 97% of total B cells, n = 2). The intermediate SPAD group had a mean CD5+ B-cell percentage that was significantly higher than that of the age-matched control group (87. 4%, n = 7, vs 52.5%, n = 20; P =.007). Patients with CVID and IgG subclass deficiency had mean CD5+ B-cell percentages that were similar to those of the age-matched control subjects.


CONCLUSIONS
Our studies demonstrate that patients with SPAD had a markedly increased percentage of CD5+ B cells in the peripheral blood as compared with age-matched control subjects and patients with other humoral deficiencies. This observation suggests that an association may be present between CD5+ B-cell predominance and SPAD.
Antall
P M
PM
Department of Pediatrics, Rainbow Babies and Children's Hospital, Northeastern Ohio Center for Immune Disorders, Cleveland, Ohio 44142, USA.
Meyerson
H
H
Kaplan
D
D
Venglarcik
J
J
Hostoffer
R W
RW
D000907:Antibodies, Bacterial / Q000097:blood*; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D018956:CD5 Antigens / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D017074:Common Variable Immunodeficiency / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000276:immunology*; D016130:Immunophenotyping; D018655:Lymphocyte Count; D008297:Male; D016555:Matched-Pair Analysis; D011135:Polysaccharides, Bacterial / Q000276:immunology*
D000907:Antibodies, Bacterial; D018956:CD5 Antigens; D011135:Polysaccharides, Bacterial