Introduction Secondary lymphoid tissue has many important roles in immunity including login to view 4 more bullets There are several types of secondary lymphoid tissue including the login to view 11 more bullets Spleen Spleen diagram The spleen is located in the left upper quadrant of the abdomen where login to view 2 more bullets There are several components of the spleen, which are divided into login to view 16 more bullets There are many clinical manifestations of asplenia including login to view 3 more bullets Lymph Nodes Lymph nodes are a diffuse network of encapsulated lymphoid tissue that login to view 2 more bullets There are several components of a lymph node, which are divided intothe login to view 22 more bullets Lymph Node Drainage Pattern Lymph Node Drainage Pattern Lymph Node Cluster Drainage Area Cervical Head Neck Hilar Lungs Mediastinal Trachea Esophagus Axillary Upper limb Breast Skin above the umbilicus Celiac Liver Stomach Spleen Pancreas Upper duodenum Superior mesenteric Lower duodenum Jejunum Ileum Colon proximal to splenic flexure Inferior mesenteric Colon between splenic flexure and upper rectum Internal iliac Lower rectum Anal canal proximal to pectinate line Bladder Cervix Prostate Paraaortic Testes Ovary Kidney Uterus Superficial inguinal Anal canal distal to pectinate line Skin below the umbilicus Scrotum Vulva Popliteal Dorsolateral foot Posterior calf