Mitogen-stimulated phospholipid synthesis in normal and immune-deficient human B cells.
Eight patients with common variable panhypogammaglobulinemia were shown in the in vitro Ig biosynthesis assay to have defective B cell responses to pokeweed mitogen (PWM). Phospholipid synthesis was assessed in the B cell plus monocyte fraction (MB) and irradiated T cells (T*) of patients and paired normal controls. Cell populations were studied separately and in the four possible combinations (1:1), with and without PWM, to reveal the effect of cell interactions. At 16 to 20 hr the mean stimulation index (SI) +/- standard error for MB cells alone was 1.01 +/- 0.02 for eight patients and 0.99 +/- 0.02 for the paired normals; the T* cell SI was 1.25 +/- 0.04 for patients and 1.28 +/- 0.05 for normals. Combinations of normal MB cells with normal T* cells showed significantly higher SI when compared with the combinations of normal MB cells with patient T* cells (p less than 0.005). However, the combination of patient MB cells with patient T* cells and the combination of patient MB cells with normal T* cells were not significantly different in SI (0.05 less than p less than 0.1). Isolation of patient and normal B cells, T* cells, and monocytes after the choline pulse showed that patient B cells gave a higher SI with normal T* help than with patient T* help. Of greatest interest is the finding that patient B cells that were defective in PWM-stimulated Ig production nevertheless showed a phospholipid synthesis response to PWM in the normal range, suggesting that the maturation defect in these B cells occurs later than the phospholipid synthesis acceleration step, or on a different pathway.
D000293:Adolescent; D000328:Adult; D000361:Agammaglobulinemia / Q000276:immunology*; D000368:Aged; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000528:radiation effects; D002450:Cell Communication; D002469:Cell Separation; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D010743:Phospholipids / Q000096:biosynthesis* / Q000528:radiation effects; D011043:Pokeweed Mitogens / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000378:metabolism / Q000528:radiation effects
D007136:Immunoglobulins; D010743:Phospholipids; D011043:Pokeweed Mitogens