Enumeration of mast cells in the human umbilical cord: implications for coiling patterns

Abstract

The abnormal umbilical cord coiling pattern affects the well-being of the newborn in different ways. Moreover the differentiation of mast cell according to these patterns may also varies. The objective: to investigate the detection and enumeration of mast cells in different patterns in human coiling cords in order to explore their effect on the newborn baby health.Materials and methods. Umbilical cord samples were collected from 105 healthy pregnant women. The cords were collected immediately after labor and kept in formalin (10%), according to coil type. Three major categories of umbilical cord coiling (normocoiled, hypercoiled, and hypocoiled) were determined according to the Umbilical Cord Index (UCI).The histological sections of the umbilical cord were collected according to UCI. This step is followed by using different histological stains, including hematoxylin and eosin and toluidine blue stains. The expression of the CD117 mast cell population in the umbilical cord tissue was determined using the immunohistochemical method in the subamniotic, perivascular and central areas. The enumeration of mast cells was done by direct counting and using Image J software. Results. The comparison of mast cell counts using Image J showed statistically significant variations (P<0.05) between normocoiled and hypercoiled cords in mast cell populations. No significant changes (P>0.05) were found in mast cell counts between normocoiled and hypocoiled umbilical cords. Conclusions. The mast cell distribution interpretation suggested that mechanical coiling during embryonic growth affects mast cell dispersal in sectioned umbilical cords. This interpretation’s functional relevance should be applied to coiling events that do not have harmful outcomes on the fetus. Future research could be done on the distribution of mast cells in the abnormally coiled umbilical cords associated with negative perinatal outcomes.