Murtadha Mezher Zidane, Haider Abdulrasool Jaafar
Perinatal Journal - 2026;34(1):81-87
The placenta supports intrauterine life through nutritional, immunologic, and endocrine functions. Hofbauer cells (HBCs) are a unique population of fetal-derived macrophages originating from fetal mesoderm that play crucial roles in regulating pregnancy. CD68 macrophages promote placental cell growth via angiogenesis induction and are predominantly located in the endosomal/lysosomal compartment within cells. To evaluate the histological and immunohistochemical expression of CD68 for HBCs and their density in placentae of different sizes. Human placental samples (n=50) were collected from Al-Qimma Surgical Hospital from normal vaginal deliveries of women aged 18-34 years. Specimens were classified into three groups based on diameter and weight: Group A (small: diameter <21cm, thickness <2.0cm, weight <=460g), Group B (large: diameter >26cm, thickness >2.6cm, weight >=500g), and Group C (control: diameter 22-25cm, thickness 2.0-2.5cm, weight 470-499g). Paraffin-embedded sections underwent H&E staining and immunohistochemical staining for CD68. Quantitative analysis was performed using Aperio ImageScope software with Positive Pixel Count algorithms. IHC expression of CD68 for HBCs was recorded as 63,690+/-31,306, 65,312+/-32,407, and 113,469+/-83,188 pixels per micron for small, large, and control group placentae, respectively. Higher expression was observed in control and large placentae compared to small placentae. Tertiary villi revealed more syncytial knots in small placentae than in large and normal-sized placentae. Low HBCs with abundant syncytial knots were more prevalent in intervillous spaces of small placentae. CD68 immunohistochemical expression serves as a specific marker for HBC detection. This study demonstrates that CD68(+) HBCs are involved in different placental structural states and are associated with developmental maturation of the placental unit. Higher CD68 expression in larger placentae indicates better placental health status.
