The anatomy and topography of the human axillary lymph nodes]

The anatomy and topography of the right and left axillary nodes were studied by the method of polychrome injections in 25 corpses of adult people dead from trauma or illnesses not related to lesions of axillary lymph nodes. Injections were made into the skin of fingers, palm and back of the hand, in the delta-shaped area, lateral surface of the chest and exterior half of the mamillary gland and also immediately into the lymph vessels of the upper extremity found with the help of interstitial injections. Detailed data on the topography of axillary lymph nodes relative to the walls, blood vessels and nerves of the axillary fossa were obtained, and the relations between the nodes were specified. From the topography of the axillary lymph nodes under study and approaching the lymph vessels as well as from literature data it is expedient to divide the axillary lymph nodes into 6 groups: lateral, medial, posterior, inferior, central and apical.     

Dendritic-cell trafficking to lymph nodes through lymphatic vessels

Antigen-presenting dendritic cells often acquire foreign antigens in peripheral tissues such as the skin. Optimal encounter with naive T cells for the presentation of these antigens requires that the dendritic cells migrate to draining lymph nodes through lymphatic vessels. In this article, we review important aspects of what is known about dendritic-cell trafficking into and through lymphatic vessels to lymph nodes. We present these findings in the context of information about lymphatic-vessel biology. Gaining a better understanding of the crosstalk between dendritic cells and lymphatic vessels during the migration of dendritic cells to lymph nodes is essential for future advances in manipulating dendritic-cell migration as a means to fine-tune immune responses in clinical settings.     

Extra-organic lymphatic vessels and regional lymph nodes of the kidneys in dogs

An anatomical investigation of extraorganic lymphatic vessels and regional renal lymph nodes has been performed in 70 dogs. The regional lymph nodes in the right kidney are stated to be quantitatively constant, as well as cranial and caudal lateroaortal lymph nodes in the left kidney in regard to the middle left lateroaortal nodes, that get lymph from the left kidney parenchyma. One middle left lateroaortal lymph node is found in 47 animals examined, two lymph nodes--in 17 animals. In 6 cases a lymphatic vessel, that gets lymph from the renal parenchyma and independently runs into the cistern of the thoracic duct is found for the first time. The variant revealed is an exception from the rule known in lymphology: lymph in its way from periphery to the central collector runs, at least, through one lymph node.     

Anatomical variants of the lymphatic vessels connecting the inguinal lymph nodes]

The study of anatomical variants of lymphatic vessels connecting inguinal lymph nodes was carried out on 56 corpses of adult persons of both sex whose deaths were not connected with lesions in the lymphatic system of the pelvis and lower extremities. The inguinal lymph nodes and their afferent and efferent lymphatic vessels were detected by the method of intradermal injection and by the method of direct injection into the lymphatic vessels. It was stated that groups of the inguinal lymph nodes, as well as the nodes in every group determined, can serve as nodes of different stages for afferent lymphatic vessels running from different parts of the body and organs.     

Individual and age variability of the anatomy and topography of the human lymph nodes

Analysis of the author's and literature data revealed two peculiarities in the lymph node anatomy. One of them is characterized with a great variability of amount and size of the nodes in every regional group. The second peculiarity is that age involution of the lymphoid tissue in the nodes is demonstrated in elderly and old persons as a decreasing amount of the lymph nodes and as their enlargement.     

Lymphatic vessels of the upper extremity and their relation to nodes in the axillary area in healthy subjects and lymph flow blockade

Large and small lymphatic vessels have been studied roentgenologically on the medial, lateral, posterior and anterior surfaces of the upper extremity in 113 patients at the age of 19-63 years at blockade of the lymphatic stream. On the medial and lateral surfaces the lymphatic vessels are filled with the contrast substance via anatomical approaches from the palmar and dorsal sides of the forearm. With isolated contrasting of various large lymphatic vessels, zones in the skin and in the subcutaneous fatty layers drained by them are revealed, as well as distribution of small vessels in the forearm and shoulder in each region. Variants of large lymphatic vessels and their tributaries are defined; an essential variability of their inflow into the axillary lymph nodes from various anatomical areas of the upper extremity is found. Into every 1-4 groups of the lymph nodes of the axillary area, 1-3 large vessels inflow, through them the contrast substance switches from the same anatomical zone repeatedly.     

Anatomy of the lymph vessels and nodes of the head and neck in green marmosets]

In 50 mature green monkeys, the lymphatic system of the skin on the hairy part of the skull (occipital, parietal, frontal) and on the face was studied. The lymphatic vessels of cranial and cervical organs flow into submental, submandibular (anterior, medial, posterior) lymph nodes and into profound cervical (cranial, medial, caudal) lymph nodes. Lymph nodes together with efferent lymphatic vessels form lymph collectors of the neck which follow the blood vessels branching: superficial jugular, profound jugular and paratracheal network.     

Innervation of mouse lymph nodes: nerve endings on muscular vessels and reticular cells

Lymph node nerve endings have been studied in 1- to 48-day-old mice. Serial sections of Epon-embedded lymph nodes were observed under the electron microscope to find the nerve endings. Most lymph node nerve fibers finally reach the smooth muscle cells of arterioles and muscular venules. Both kinds of vascular endings are similar, although endings are less numerous on venules. Nerve endings consist of one or more nerve processes surrounded by a usually incomplete Schwann cell sheath; frequently, axons show wide areas directly facing the muscle cells. The distance between such a naked axon and a myocyte ranges from 100 to 800 nm. Small granulated and clear vesicles are especially abundant in varicosities of nerve processes that are located very close to muscle cells. Nerve endings of lymph node vasculature probably correspond to vasomotor sympathetic adrenergic endings, regulating the degree of contraction of vessels which have a muscular layer. Other kinds of nerve endings also exist in lymph nodes: some axons appear free in the stroma and contact the surfaces of reticular cells; the latter also extend delicate cytoplasmic processes that surround the axons. The functional significance of nerve cell-reticular cell contacts is unknown.     

Dynamic imaging of lymphatic vessels and lymph nodes using a bimodal nanoparticulate contrast agent

BACKGROUND: Evaluation of lymphedema and lymph node metastasis in humans has relied primarily on invasive or radioactive modalities. While noninvasive technologies such as magnetic resonance imaging (MRI) offer the potential for true three-dimensional imaging of lymphatic structures, invasive modalities, such as optical fluorescence microscopy, provide higher resolution and clearer delineation of both lymph nodes and lymphatic vessels. Thus, contrast agents that image lymphatic vessels and lymph nodes by both fluorescence and MRI may further enhance our understanding of the structure and function of the lymphatic system. Recent applications of bimodal (fluorescence and MR) contrast agents in mice have not achieved clear visualization of lymphatic vessels and nodes. Here the authors describe the development of a nanoparticulate contrast agent that is taken up by lymphatic vessels to draining lymph nodes and detected by both modalities. METHODS: A unique nanoparticulate contrast agent composed of a polyamidoamine dendrimer core conjugated to paramagnetic contrast agents and fluorescent probes was synthesized. Anesthetized mice were injected with the nanoparticulates in the hind footpads and imaged by MR and fluorescence microscopy. High resolution MR and fluorescence images were obtained and compared to traditional techniques for lymphatic visualization using Evans blue dye. RESULTS: Lymph nodes and lymphatic vessels were clearly observed by both MRI and fluorescence microscopy using the bimodal nanoparticulate contrast agent. Characteristic tail-lymphatics were also visualized by both modalities. Contrast imaging yielded a higher resolution than the traditional method employing Evans blue dye. MR data correlated with fluorescence and Evans blue dye imaging. CONCLUSION: A bimodal nanoparticulate contrast agent facilitates the visualization of lymphatic vessels and lymph nodes by both fluorescence microscopy and MRI with strong correlation between the two modalities. This agent may translate to applications such as the assessment of malignancy and lymphedema in humans and the evaluation of lymphatic vessel function and morphology in animal models.     

Ontogenetic aspects of immune-complex trapping in the spleen and popliteal lymph nodes of the rat

Summary An ontogenetic approach was used to obtain information about the relation between structure and function of lymphoid tissues. In particular the development of the capacity to trap immune complexes was studied in relation to the development of the lymphoid compartments. For this purpose isologous horseradish (HRP)-anti-HRP complexes were injected into neonatal rats, and their fate was studied in the spleen and popliteal lymph nodes. Immune-complex trapping occurred as soon as primary follicles could be recognized; without follicles no trapping was observed. Several explanations for this simultaneous development of trapping capacity and follicular structure are discussed.Abbreviations i.v. intravenous(ly) - s.c. subcutaneous(ly) - HRP horseradish peroxidase - MZ marginal zone - PALS periarteriolar lymphocyte sheath