Summary: The absence of germinal centers (GCs) in cartilaginous fishes lies at odds with data showing that nurse sharks can produce robust antigen-specific responses and affinity mature their B cell repertoires. To investigate this apparent incongruity. we performed RNA sequencing on single nuclei. allowing us to characterize the cell types present in the nurse shark spleen. https://parisnaturalfoodes.shop/product-category/dr-formulated-kids-watermelon-5bil/