Lymphoid tissues of the snake, Spalerosophis diadema, in the different seasons.

摘要: Abstract The thymus in the snake, Spalerosophis diadema , is lymphoepithelial, clearly differentiated into cortex and medulla; it undergoes involution both winter summer. During these seasons, spleen divided distinct white red pulps. In spring autumn, lymphocytes completely obscure splenic stroma so that pulp boundaries are obliterated. Gut-associated lymphoid tissue (GALT) extensively distributed along entire gastrointestinal tract. Structures resembling Peyer's patches, except being composed of only two adjacent accumulations, prominent small intestine while decrease remarkably number size summer (the breeding season). contrast, gut-associated aggregates numerous throughout year. Differential sensitivity to seasonal variation suggested as a possible marker for functional lymphocyte populations reptiles.