COMPLEMENT FACTOR-H MESSENGER-RNA IN EPSTEIN-BARR VIRUS-TRANSFORMED B-LYMPHOCYTES OF A FACTOR-H-DEFICIENT PATIENT - DETECTION BY POLYMERASECHAIN-REACTION

A Spanish family with a hereditary deficiency of factor H was identifi ed in previous studies. The deficiency was subtotal as low amounts of a dysmorphic molecule with partial identity to factor H were detected in her serum. The aim of this study was to obtain further characterisa tion of her deficiency employing her immortalised lymphocytes. After p urification of mRNA from her Epstein-Barr virus (EBV)-transformed lymp hocytes and from Raji cells, and cDNA synthesis we succeeded in amplif ying cDNA which codes for factor H domains 13-15 from both cell lines, using specific oligonucleotides. The amplified fragments were indisti nguishable from the one which was amplified from the control cloned cD NA template. The failure to amplify the 3' end of the patient's factor H mRNA suggests that the mRNA is truncated, which is consistent with the characteristics of the dysmorphic protein. Thus, factor H mRNA was detectable in Raji cells and the patient's EBV-transformed lymphocyte s. We suggest that immortalised B lymphocytes can be used for the stud y of a range of inherited complement deficiencies.