Correspondence

The Vulture and Stem Cells

N Engl J Med 2003; 349:1480-1481October 9, 2003

Article

To the Editor:

Rosenthal (July 17 issue)1 begins her article by considering the myth of Prometheus. She says that a vulture preyed daily on his self-renewing liver. Indeed, Greek mythology tells us that a bird ate Prometheus's liver, but older sources allude to an eagle instead of a vulture2,3 (Figure 1Figure 1Prometheus Attacked by Zeus's Eagle.). This is not a trivial point, because vultures are scavengers, whereas eagles are birds of prey. Vultures would never eat living animals. This cultural imprecision might seem unimportant, but terminology is key with respect to the issue of the “stem-cell promise.” Semantic differences between terms such as “nuclear transfer” and “therapeutic cloning”are very important.

To continue the theme of Greek mythology, we suggest the myth of Phaethon. Helios (the Sun) drove his scalding carriage through the skies every day. Having made insistent requests, Phaethon, Helios's young and inexpert son, managed to drive the chariot for a day, but he could not stop the runaway horses, whose path threatened to burn the Earth. Annoyed, Zeus struck Phaethon with a lightning bolt. Since adult stem cells appear to show clinical safety and feasibility,4,5 it should be noted that other sources of cell therapy could be dangerous,6 at least until we have wider knowledge about how to control them.

Damian Garcia-Olmo, M.D., Ph.D.
Universidad Autonoma de Madrid, 28046 Madrid, Spain
damian.garcia@uam.es

Miguel-Angel Garcia-Olmo, M.A.
San Antonio University–UCAM, 30107 Murcia, Spain

6 References

1. 1

   Rosenthal N. Prometheus's vulture and the stem-cell promise. N Engl J Med 2003;349:267-274
   Full Text | Web of Science | Medline

2. 2

   Theogony [lines 520-525]. In: Hesiod. Homeric hymns: epic cycle: Homerica. Loeb classical library. Series no. 57. Evelyn-White HG, trans. Cambridge, Mass.: Harvard University Press, 1969.
   

3. 3

   Prometheus bound [lines 1020-1025]. In: Aeschylus. Vol. 1. Suppliant maidens: Persians: Prometheus: Seven against Thebes. Loeb classical library. Series no. 145. Smyth HW, trans. Cambridge, Mass.: Harvard University Press, 1969.
   

4. 4

   Orlic D. Adult bone marrow stem cells regenerate myocardium in ischemic heart disease. Ann N Y Acad Sci 2003;996:152-157
   CrossRef | Web of Science | Medline

5. 5

   Garcia-Olmo D, Garcia-Arranz M, Garcia LG, et al. Autologous stem cell transplantation for treatment of rectovaginal fistula in perianal Crohn's disease: a new cell-based therapy. Int J Colorectal Dis 2003;18:451-454
   CrossRef | Web of Science | Medline

6. 6

   Hochedlinger K, Jaenisch R. Nuclear transplantation, embryonic stem cells, and the potential for cell therapy. N Engl J Med 2003;349:275-286
   Full Text | Web of Science | Medline

Author/Editor Response

I commend my colleagues for their careful perusal of the ancient literature, having correctly identified two sources of the Greek legend where an eagle, probably a symbol of Zeus himself, was sent to torture the Titan Prometheus. As noted by other scholars,1 the Promethean tale resembles one described in Homer's Odyssey, in which Tityos is tormented by two vultures and may have been the original victim of this punishment.

An earlier legend holds precedence in the Caucasus, where earthquakes were allegedly caused by the struggles of a fierce giant, fettered in a mountain cave for his various impieties while a vulture pecked intermittently at his bowels.2 Perhaps it was this ancient version to which Bulfinch's The Age of Fable alludes in describing Prometheus “chained to a rock on Mount Caucasus, where a vulture preyed on his liver.”3 Other literary figures, including Byron, have also described the vulture of Promethean legend.4

As for the argument that vultures never eat live flesh, this is not strictly true. They are omnivorous, feeding chiefly on carrion because they have relatively weak beaks and lack the strength of other birds of prey. They rarely attack live prey unless it is rendered helpless. One might argue that Prometheus was defenseless against the attacks of emboldened raptors, but the true ornithologic identity of his devourer remains enshrouded in the mists of myth. Let us hope that as scientists we leave less indeterminate the documentation of the illusive stem cell's true identity.

(I am indebted to Professor Brian Bothwick, Department of Classics and Ancient History, University of Western Australia, for his invaluable tutelage and for the use of his excellent library.)

Nadia Rosenthal, Ph.D.
European Molecular Biology Laboratory, 00016 Monterotondo, Italy

4 References

1. 1

   Hesiod. Theogony. West ML, trans. Oxford, England: Clarendon Press, 1966.
   

2. 2

   Olrik A. Ragnarök. Ranisch W, trans. Berlin, Germany: W. de Gruyter, 1922.
   

3. 3

   Bulfinch T. The age of fable: or stories of gods and heroes. Boston: Charles E. Brown, 1855.
   

4. 4

   Prometheus. In: Byron GG. Works. London: John Murray, 1832.
   

Citing Articles (3)

Citing Articles

1. 1

   Dina G. Tiniakos, Apostolos Kandilis, Stephen A. Geller. (2010) Tityus: A forgotten myth of liver regeneration. Journal of Hepatology 53:2, 357-361
   CrossRef

2. 2

   M. Valdés Chavarri, D. Pascual Figal, F. Prósper Cardoso, J. Moreno Montañés, D. García Olmos, J.A. Barcia Albacar. (2005) Medicina regenerativa con células madre adultas. Revista Clínica Española 205:11, 556-564
   CrossRef

3. 3

   Damián García-Olmo, Mariano García-Arranz, Dolores Herreros, Isabel Pascual, Concepción Peiro, José Antonio Rodríguez-Montes. (2005) A Phase I Clinical Trial of the Treatment of Crohn's Fistula by Adipose Mesenchymal Stem Cell Transplantation. Diseases of the Colon & Rectum 48:7, 1416-1423
   CrossRef