Biomedical Engineering Reference
In-Depth Information
Figure 2
. Total lymphocyte output from the thoracic duct plotted as a function of body mass
for the hamster, rat, guinea pig, cat, rabbit, monkey, dog, goat, and human (in order of mass).
Equation for the fitted line is
y
= 211930
x
0.73
.
system have been well-studied (see (2)). An analogous theory for the lymphatic
system still needs to be developed. Hopefully such a theory will address ques-
tions such as how does the size and number of lymph nodes scale with animal
size? Do big animals have more lymph nodes or bigger lymph nodes than
smaller mammals? Also, if scaling relations can be developed, they may open a
window into a better understanding of the relationship between the human im-
mune system and that of other species, which are commonly used as "model
systems" for studying the effects of drugs and immune system modifiers. A
more informed approach to such studies would be nothing but helpful.
4.
ACKNOWLEDGMENTS
We thank Geoffrey West for valuable conversations about this work. Por-
tions of this work were done under the auspices of the US Department of Energy
under contract W-7405-ENG-36 and supported by NIH grant AI28433. This
work was also facilitated by interactions at the Santa Fe Institute and supported
at the Santa Fe Institute by a grant from the Joseph P. and Jeanne M. Sullivan
Foundation.
5.
REFERENCES
1.
Langman RE, Cohn M. 1987. The elephant-tadpole paradox necessitates the concept of a unit
of B cell function: the protecton.
Mol Immunol
24
:675-697.
2.
West GB, Brown JH, Enquist BJ. 1997. A general model for the origin of allometric scaling
laws in biology.
Science
276
:122-126.
3.
Brown JH, West GB. 2000.
Scaling in biology
. Oxford UP, New York.
