Common variable immunodeficiency with increased surface IgM-positive double-bearing B cells.
We report a case of common variable immunodeficiency (CVI) that shows low levels of IgG and IgA, but a normal quantitative or qualitative level of IgM. T-cell functions were not disturbed. Increased numbers of surface IgM (sIgM) and sIgD, sIgM and sIgG, sIgM and sIgA double-bearing B cells were observed as compared with a control. No IgG and IgA induction upon stimulation with Staphylococcus aureus Cowan I (SAC) and recombinant interleukin-2 (rIL-2), or pokeweed mitogen (PWM) and rIL-4 or rIL-6 was observed, although there was proliferation. Although mu mRNA was expressed as much as in a healthy control, transcription of gamma mRNA and alpha mRNA was very low. Furthermore, no enhanced effects of gamma mRNA and alpha mRNA were recognized upon stimulation with rIL-4 and rIL-6. These results suggest that the patient's B cells might be defective at the switching process from mu, mu and delta, mu and gamma to gamma or mu and alpha to alpha.
Motoyoshi
F
F
Department of Pediatrics, Gifu University School of Medicine, Japan.
Mori
S
S
Kondo
N
N
Kaneko
H
H
Ozawa
T
T
Kuwabara
N
N
Kato
Y
Y
Takemura
M
M
Noma
A
A
Orii
T
T
D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D005260:Female; D015870:Gene Expression; D005803:Genes, Immunoglobulin; D006801:Humans; D007075:Immunoglobulin M / Q000378:metabolism*; D007153:Immunologic Deficiency Syndromes / Q000276:immunology*; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics; D011947:Receptors, Antigen, B-Cell / Q000276:immunology*
D007075:Immunoglobulin M; D012333:RNA, Messenger; D011947:Receptors, Antigen, B-Cell