A familial hyperalphalipoproteinemia with low uptake of high density lipoproteins into peripheral lymphocytes.
A patient with an extremely high level of high density lipoprotein (HDL)-cholesterol and HDLc-like particles in the serum is discussed. The patient was a 46-year-old female with a serum total cholesterol concentration of 382 mg/dl and HDL-cholesterol level of 214 mg/dl. The HDL-cholesterol levels of her mother, brother, sister and 2 of her daughters were 82 mg/dl, 82 mg/dl, 74 mg/dl, 82 mg/dl and 82 mg/dl, respectively (mean HDL-cholesterol levels of control subjects: 52 +/- 6 mg/dl in males and 55 +/- 8 mg/dl in females). Her serum apolipoprotein A-I and E levels were elevated. Zonal ultracentrifugal analysis of her serum lipoproteins showed that the increased level of HDL-cholesterol was mainly due to HDL2; HDLc-like particles were also recognized between the LDL and HDL fractions. The incorporation of the patient's HDL and HDLc-like particles into cultured HepG2 cells was almost the same as that of HDL (1.063 less than d less than 1.21) from normal control serum. The incorporation of normal control HDL into the patient's peripheral blood lymphocytes was markedly less than that into lymphocytes from normal controls. These findings are discussed in terms of the reason for hyperalphalipoproteinemia in this patient.