Here is what I got back form our faculty adviser. Hopefully the additional detail is valuable for you.
"The selection of types available in OS is not very robust for a research institution, so the question of adding types comes up frequently. I never support adding types unless there is good justification both scientifically and logistically and there is not a global type that will adequately describe the collection. I prefer using what is available so as to remain compatible with other users of OS. We do not want to create a tower of Babel.
Examples: There may be instances where investigators sort cells by subtype, eg T Cells may be Natural Killer (NKT) Cells, Effector, Helper, Memory, Regulatory (suppressor), Mucosal Associated Invariant, or Gamma Delta. All are lymphocytes, but are subclasses. Therefore, It may be good to add Lymphocyte as a specimen type, but the subtypes would be a custom field.
Science is evolving, so there may come a time when “enteroid” or “organoid” will have to be added. These are human stem cell cultures that replicate human tissues. These will be a new type scientifically by nature of their origin from stem cells and subsequent cloning. Whether they are liver, colon, ileum, or lung is found in a custom field. This is an evolving area of research that has clinical implications and thus will require a type designation in the future.
Scientists will often isolate subtypes of specimens, especially with cells. These are most often described in custom fields and far less often are new types. Eg, cancer tissue is described in an annotation, but is still tissue and from the original organ. Tissues from metastatic cancer are annotated to give detail concerning the tissue of origin and the location where the metastatic tissue was captured. They are not new types."
