Objective:　To　investigate　localization　and　distribution　of　integrin　subunit　beta　1,　beta　2　and　beta　3　and　morphological　changes　of　ligand-recepter　binding　in　thrombi　of　acute　pulmonary　embolism　(PE)　patients　and　explore　activation　of　circulated　immune　cells,　inflammatory　immune　adherence　and　coagulation　response　in　acute　venous　thrombosis.　Methods:　Thrombi　were　collected　from　patients　with　acute　PE.　Immunohistochemistry　was　done　to　detect　the　expression　and　distribution　of　integrin　beta　1,　beta　2　and　beta　3　in　cells　within　thrombi,　and　ligands　of　integrin　subunit　beta　1,　beta　2　and　beta　3　were　also　determined　by　immunohistochemistry　within　the　thrombi.　Results:　1)　Acute　venous　thrombi　were　red　thrombi　composed　of　skeletons　and　filamentous　mesh　containing　large　amounts　of　red　blood　cells　and　white　blood　cells;　2)　Integrin　subunit　beta　1,　beta　2　and　beta　3　were　expressed　on　lymphocytes,　neutrophils　and　platelets;　3)　No　expression　of　integrin　beta　1　ligands:　Laminin,　Fibronectin,　Collagen　I　or　Collagen-II　on　lymphocytes;　integrin　beta　2　ligands　including　ICAM,　factor　X　and　iC3b　are　distributed　on　neutrophils,　and　ligand　fibrinogen　bound　to　neutrophils;　integrin　beta　3　was　expressed　on　platelets　which　form　the　skeleton　of　thrombi　and　bound　to　fibrinogen　to　construct　mesh　structure;　4)　Factor　Xa　was　expressed　on　the　filamentous　mesh;　5)　Filamentous　mesh　was　fully　filled　with　red　blood　cell　dominant　blood　cells.　Conclusion:　Acute　venous　thrombosis　is　an　activation　process　of　circulated　lymphocytes,　neutrophils　and　platelets　mainly,　and　a　whole　process　including　integrin　subunit　beta　2　and　beta　3　binding　with　their　ligands.　Activation　of　immune　cells,　inflammatory　immune　adherence　and　coagulation　response　are　involved　in　the　acute　venous　thrombosis.