Lymphatic System: A Path for Drug Delivery

Abstract

A Lymphatic system is a network like system being extended all over the body and useful targets for efficient drug delivery for drugs having poor oral bioavailability in the intestine and less absorbed into systemic circulation because of drug degradation in GI tract. Lymphatic targeting is not only to treat various infections not limited to pathological conditions like human immunodeficiency virus and other diseases but also used in diagnosis of tumours along with metastasis. Moreover, lymph nodes are the site for faster spread source to tumours via metastasis. Under these circumstances, there is a need for effective delivery of drugs towards and through lymphatic networks. Nano based systems and lipid based systems have unique features as necessary candidates for lymphatic delivery. The review provides information about different routes, drug transport in the lymphatic system, physicochemical properties which give impact on lymphatic delivery.

Hybrid Lymphatic Drug Delivery Vehicles as a New Avenue for Targeted Therapy: Lymphatic Trafficking, Applications, Challenges, and Future Horizons

“…Several types of bacteria, viruses, and parasites migrate and colonize within LS that considered a red spot for relapse after completion of therapy. This occurs when the patient is subjected to an appropriate therapeutic protocol and a minimal concentration of the drug is attained within LS (Sunkari and Sunduru 2020 ). For example, Bacillus anthracis bacteria produce endospores following their phagocytosis by macrophages.…”

Nano-hydroxyapatite improves intestinal absorption of acetazolamide (BCS Class IV drug)–but how?

“…The main absorption pathways for nutrients and drugs in the intestinal tract are the intercellular and intracellular pathways of the epithelium, while many large molecules and/or insoluble substances are absorbed via the lymphatic system [ 51 ]. The tight junction forms a barrier between cells, blocking the paracellular pathway, through which many substances are nevertheless absorbed by passive transport.…”

“…While most substances entering the body from the small intestine are taken up via the intestinal villi, as an alternative route, especially for the entry of large molecules, substances not absorbed via the villi may enter via the Peyer’s patch tissues [ 51 , 59 ]. These contain cells called microfold cells (M cells) that are known to absorb large substances by endocytosis on the mucosal side of the cell and expel them from the basal membrane side in a transcellular process described as transcytosis [ 60 ].…”