Evaluation of neutral honey as a tissue fixative in histopathology

In histopathology, fixation is an initial and the most critical step in the tissue processing which is important for diagnostic microscopy. The purpose of the fixation is to preserve the tissue as in life-like condition by preventing autolysis and bacterial putrefaction. In routine laboratory, 10% neutral buffered formalin is the fixative of choice because it is ready available, cheap, fast technique, allowing long-term storage, suitable for post fixation processing and easy to use as well as its ability to prevent autolysis and bacterial growth. However, formalin is a human carcinogen. Also, the extraction of intact nucleic acids (DNA and mRNA) for molecular tests, from samples processed by formalin is difficult or impossible due to a DNA-protein or DNA-DNA crosslinks induced by formalin. To the best of our knowledge, neutral honey not the natural or artificial honeys, has not been tested to fix histological tissues. Thus, we aim to examine the efficiency of neutral buffered honey to fix histological tissues. This might replace formalin with a safer equal alternative fixative. Four specimens of skin, stomach, lung, heart, muscle, liver, kidney and pancreas from rat tissues will be used to evaluate natural, neutral, artificial honeys as tissue fixatives and compared with 10% neutral buffered formalin (NBF) as a gold standard fixative. Nuclear and cytoplasmic staining, cell morphology, clarity and uniformity of staining, quality of IHC and DNA will be used to compare the efficiency of different honeys. Independent sample t-test will be used to measure p ? value for each fixative and compared with the gold standard fixative.