Paneth cells are cone-shaped cells specialized in defending the intestinal mucosa against microbes (non-specific immunity). They are located in the crypts of the small intestine. Similar to other cells with high synthetic activity, they have a developed Golgi apparatus and a basophilic cytoplasm, the apical part of which is filled with markedly acidophilic granules containing:
The secretion of these granules into the intestinal lumen has an antimicrobial effect. 
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