View source for WBR0830

 {{WBRQuestion
|QuestionAuthor= {{YD}} (Reviewed by  {{YD}})
|ExamType=USMLE Step 1
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|MainCategory=Pathology
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|SubCategory=General Principles
|MainCategory=Pathology
|MainCategory=Pathology
|SubCategory=General Principles
|Prompt=A pathologist is studying the process of healing in rats. Following acute injury, he demonstrates that inflammatory cells produce growth factors that help in wound healing. Growth factors are capable of stimulating specific cells to migrate to the site of the wound. During the proliferation stage of wound healing, which immunohistochemical stain will most likely be strongly positive?
|Explanation=Early wound healing is characterized by the presence of the inflammatory cells that produce growth factors to stimulate the migration and proliferation of fibroblasts. Fibroblasts are secretory cells that produce extracellular matrix abundant in collagen. Later during the healing process (proliferation stage) , fibroblasts then differentiate into myofibroblasts to start the process of contracture. Eventually, myofibroblasts normally disappear. Their persistence at the site is associated with cancers, fibromatoses, and fibrotic diseases. Fibroblasts are recognized by immunohistochemical analysis by their spindle-shaped appearance and their strong positivity for vimentin stain.
|AnswerA=Desmin
|AnswerAExp=Desmin is a stain for muscle cells.
|AnswerB=Cytokeratin
|AnswerBExp=Cytokeratin is a stain for epithelial cells.
|AnswerC=GFAP
|AnswerCExp=GFAP is a stain for neuroglia.
|AnswerD=Neurofilaments
|AnswerDExp=Neurofilaments is a stain for neurons.
|AnswerE=Vimentin
|AnswerEExp=Vimentin is a stain for connective tissue, including fibroblasts.
|EducationalObjectives=Vimentin stains fibroblasts, a component of connective tissue that is responsible for the early wound healing.
|References=Goodpaster T, Legesse-Miller A, Hameed MR, et al. An immunohistochemical method for identifying fibroblasts in formalin-fixed, paraffin-embedded tissue. J Histochem Cytochem. 2008;56(4):347-358.<br>
First Aid 2014 page 78
|RightAnswer=E
|WBRKeyword=Vimentin, Stain, Immunohistochemical, Intermediate filaments, Fibroblast, Fibroblasts, Healing, Wound healing, Connective tissue
|Approved=Yes
}}