Abstract
Abstract Five patients with severe combined immune deficiency (CID) disease and diminished serum C1q (27 to 44% of normal) who received bone marrow transplantation to reconstitute immunologic function were studied. The diagnosis of CID was made according to the WHO criteria. Serum levels of C1q were quantitated by radial immunodiffusion according to the method of Hanauer and Christian. Agematched controls had a serum concentration of 20.2 µg N/ml, whereas our patients with CID had a mean level of 6.3 µg N/ml. Three of the five patients had successful engraftment, partial or full immunologic reconstitution, and an increase in the serum C1q to normal after bone marrow transplantation. One patient failed to have a graft “take” with no evidence of immunologic reconstitution, and the C1q remained very low. In the fifth patient the serum levels of C1q fluctuated widely, but despite normal immunologic function the C1q remained deficient.