Exosomes are formed in multivesicular endosomes.
Multivesicular endosomes take up cytoplasm and cytoplasmic molecular content and package it into membrane-bound vesicles called exosomes. The multivesicular endosomes release the exosomes into the extracellular space.
The type of cargo carried by exosomes is nucleic acids and proteins. Exosomes are secreted by all cell types; their cargo differs between cell types and can be found in all bodily fluids such as blood, saliva, and urine.
Based on this information and your general knowledge of cell biology, which ONE of the following can you deduce NOT to be included in exosome cargo?