Howell-Jolly (H-J) bodies have classically been considered intracellular remnants of the normoblast nucleus that once occupied the red blood cell in which the inclusion is seen. Recent work, supported by light microscopic findings, has suggested these inclusions may be extracellular. Extensive scanning and electron microscopic study of H-J red blood cells has confirmed their intracellular location.
Hilberg RW, Ringle RD, Balcerzak SP. Howell-Jolly BodiesIntracellular or Extracellular?. Arch Intern Med. 1973;131(2):236-237. doi:10.1001/archinte.1973.00320080072009