Novel threadlike structures (Bonghan ducts) inside lymphatic vessels of rabbits visualized with a Janus Green B staining method

Abstract

A staining method has been developed for in situ and in vivo observation of a threadlike tissue afloat inside the lymphatic vessels of rabbits without adherence to the vessel wall. The existence of this novel structure was not noticed previously because it is extremely difficult to detect it by microscopic inspection of lymphatic vessels. We have found a method that utilizes Janus Green B (JGB), which stained heavily the novel structure. The tissue was studied by confocal laser scanning microscopy (CLSM), light microscopy, and cryoscanning electron microscopy (cryo-SEM). The CLSM image obtained by acridine orange staining of the novel tissue revealed its characteristic nuclei distribution: rod-shaped nuclei of 10-20 microm length aligned in a broken-line/striped fashion. Hematoxylin and eosin staining revealed the threadlike structure passing through a lymphatic valve as histologically distinct from lymphatic vessels and valves. The cryo-SEM image showed the threadlike structure inside a collapsed lymphatic vessel. There were spherical globular structures observable inside sinuses in a rapidly frozen sample, which suggests liquid flowing through the longitudinal ductules in the threadlike structure. The specific staining of the JGB suggests that these threadlike structures inside lymphatic vessels have a high density of mitochondria in their cells and/or nerve-like properties, either of which may provide important clues to their physiological function.

Adult Stem Cells from the Hyaluronic Acid-Rich Node and Duct System Differentiate into Neuronal Cells and Repair Brain Injury

“…Elements of the intravascular HAR-ND are invisible without staining because typically they are very thin and transparent. The diameter of the intralymphatic HAR-NDS was 15-20 times smaller than the diameter of the surrounding lymphatic vessels [15]. The HAR-NDS diameter became artificially enlarged when alcian blue was injected (Fig.…”

“…We recently described a hyaluronic acid-rich node and duct system (HAR-NDS) [11,12] also known as the Bonghan (or Primo) vascular system [13][14][15][16]. We referred to the nodes and ducts as hyaluronic acid-rich node and hyaluronic acid-rich duct, respectively, and to the two together as hyaluronic acid-rich node(s) and duct(s) (HAR-ND) [12].…”

A Transformative Approach to Cancer Metastasis: Primo Vascular System as a Novel Microenvironment for Cancer Stem Cells

“…The PVS floating in the lymph ducts has been extensively studied in rabbits [12] , rats [13] , and mice [14] . The lymph PVS is visible in vivo and in situ with suitable staining dyes like Alcian blue [15] and fluorescent nanoparticles [13] .…”

Mechanisms of Action of Acupuncture for Chronic Pain Relief – Polymodal Receptors Are the Key Candidates

“…31 Tenderness has been one of the clearest physiological characteristics of acupuncture points since ancient medical literature. Our previous survey also clearly demonstrated that tender points and palpable bands, as well as formal acupuncture points, were used in clinical treatment by well trained Japanese acupuncturists.…”