The umbilical cord connects the developing fetus to the placenta, acting as a lifeline for nutrient and gas exchange throughout gestation. This structure requires specialized internal architecture to withstand the physical demands of fetal movement and uterine contractions. The core of this resilience comes from a unique, gelatinous substance that encases the blood vessels, known as Wharton’s Jelly.
Defining Wharton’s Jelly
Wharton’s Jelly is a specialized mucous connective tissue found within the umbilical cord. It surrounds the three umbilical vessels—typically two arteries and one vein—that run along the length of the cord. Characterized by its pale white or grayish mucoid texture, the substance is soft yet firm and constitutes the bulk of the cord’s volume.
The anatomical arrangement places the jelly between the amniotic membrane covering the cord’s exterior and the vessels themselves, providing a buffer layer. The integrity of this gelatinous matrix defines the cord’s shape and flexibility.
The material was first described by the English physician and anatomist Thomas Wharton in his 1656 publication, Adenographia, which is the origin of its common name.
The Protective Role in the Umbilical Cord
The primary function of Wharton’s Jelly is to ensure the uninterrupted flow of blood between the placenta and the fetus. It acts as a cushion that resists physical deformation. The turgor and resilience of the jelly protect the umbilical vessels from external pressure, torsion, or knotting during fetal movements.
This protective quality is rooted in the jelly’s ability to retain large amounts of water, forming a firm, hydrated gel that maintains the cord’s architectural integrity. The jelly’s viscoelastic properties allow it to absorb mechanical stresses without collapsing the enclosed blood vessels. The substance also plays a role in the physiological process of birth; the sudden temperature change upon delivery causes the jelly to cool and shrink, naturally constricting the umbilical vessels in a process known as physiological clamping.
Unique Cellular and Structural Makeup
The protective properties of Wharton’s Jelly are directly linked to its specific composition, which is distinct from other connective tissues in the body. The substance is composed of a sparse population of cells embedded within a dense and complex extracellular matrix (ECM). The cell population primarily includes fibroblasts and macrophages that maintain the matrix’s structural integrity.
The tissue is a rich source of Mesenchymal Stem Cells (MSCs), often referred to as Wharton’s Jelly Mesenchymal Stem Cells (WJ-MSCs). These cells are considered “naïve” compared to adult-derived MSCs and exhibit a high capacity for self-renewal and differentiation into various cell types. The gelatinous texture is conferred by the ECM, which is highly concentrated with hydrophilic glycosaminoglycans, particularly hyaluronic acid and chondroitin sulfate. Hyaluronic acid is effective at binding water molecules, creating the turgid, shock-absorbing gel fundamental to the jelly’s protective function.
Applications in Regenerative Medicine
The Mesenchymal Stem Cells (WJ-MSCs) isolated from Wharton’s Jelly have generated significant interest in regenerative medicine due to their unique biological profile. WJ-MSCs are typically harvested from the umbilical cord tissue after birth using non-invasive techniques, such as enzymatic digestion or explant culture, and can be cryopreserved and banked for future use. This source is ethically advantageous because the umbilical cord is considered medical waste following delivery, avoiding the controversies associated with other stem cell sources.
Compared to MSCs derived from bone marrow or adipose tissue, WJ-MSCs demonstrate a superior proliferation rate and low immunogenicity. This immune-privileged nature makes them excellent candidates for allogeneic (non-self) transplantation. Clinical trials are investigating their potential to promote tissue repair, regulate the immune system, and differentiate into specialized cells. Research is exploring their potent immunomodulatory and anti-inflammatory effects in treating conditions such as neurological disorders, cardiovascular disease, and autoimmune conditions.