IL6 and hydrops fetalis: This is why we failed to identify cytokine proteins (IL-6, TNF-alpha, etc.), receptor expression (sTNF-R1, sTNF-R2, sFAS, etc.)and well-established HF markers, for example, BNP and NT-proBNP, which we determined in a previous study performed with Western blot techniques and mRNA expression quantified by quantitative real-time polymerase chain reaction (RT-PCR) in the same cardiac tissue [55].