HSPD1 and obesity due to melanocortin 4 receptor deficiency: A similar decoupling of obesity and metabolic disturbances has been noted in other studies when suppressing adaptive immunity, for example in RAG-1-deficient mice, which lack mature T and B lymphocytes.8 Given observations that LDL production is increased by obesity19 and that HSP60 autoimmunity contributes to atherosclerosis,12 the reduction in LDL levels achieved by HSP60 peptide treatment is of interest.