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Biorheological Properties of Reconstructed Erythrocytes and its Function of

Carrying-Releasing Oxygen

Xiang Wang, Wei Gao, Weiyan Peng, Jiaxin Xie and Yaojin LiCollege of Bioengineering, Chongqing University, Chongqing, P.R. CHINA

Abstract: Erythrocyte shape and biomechanical properties have close relation to its physiological function. In this research theerythrocyte was reconstructed with natural structure protein and lipids based on cellular mechanics and hemorheology concepts. The

biomechanical properties of the reconstructed erythrocyte were determined with the micropipette aspiration system. The shapes of

reconstructed erythrocyte were obtained with electron scanning microscope. The oxygen carrying-releasing function was analyzed with

the HEMOX analyzer from TCS, the experimental results indicated that the reconstructed erythrocytes were similar to the natural

erythrocyte: having biconcave disc shape, good deformability and carrying-releasing oxygen function.

Keywords:biorheological properties, reconstructed erythrocytes, carrying-releasing oxygen

INTRODUCTION

The blood substitute has been a hot researching focus

around the world. As a blood substitute, its function

should be comparable to that of natural hemoglobin,

carrying and releasing oxygen around the human bodies.

The present known blood substitutes are perfluorocarbon,

various kinds of modified hemoglobin by chemicaltechnology and gene engineering. However, the perfluor-

ocarbon molecule is hard to metabolize and imposes

harmful effects on human health due to its accumulation

in vivo. Gene engineering produced human hemoglobin

from tobacco plant root and has been used to produce

human hemoglobin, but the high cost and low yield

hinder the high production. In addition, liposome has

been used to envelope hemoglobin to be used as a blood

substitute. However, the procedure has only been carried

out in labs at present [1,2].

Erythrocyte shape and biomechanical properties have

close relation to the oxygen carrying-releasing dynamics

function. But up to now little research on artificial blood

substitutes has realized this viewpoint and mainly focused

the studies on how to use blood substitute simulating

physiology of normal red blood cells [3,4]. The main

problem of these products lies in the lack of natural

configuration, and deformability needed in circulation

like those in mature RBCs that would hinder its oxygen

carrying-releasing dynamics function.

In this research, we have studied the biorheological

properties of reconstructed erythrocytes and their function

of carrying-releasing oxygen. The reconstruction of red

blood cells in vitro could be of great significance in the

biomedical research field and may potentially solve the

shortage problems of blood supply.

MATERIALS AND METHODS

In this research the biomechanical properties of the

reconstructed RBC were determined with the micropipette

aspiration system, etc [5,6]. The image of reconstructed

RBC was obtained with an electron scanning microscope.

The dynamics function of carrying-releasing oxygen was

analyzed with the HEMOX analyzer from TCS and the

dynamics analytical system established in our lab (Figures

1 and 2).

RESULTS AND DISCUSSION

The experimental results indicated that the reconstructed

erythrocytes have a biconcave disc form that was similar

to the natural erythrocyte (Figures 3A, 3B, 3C and 3D).

Compared with normal erythrocytes the reconstructed

erythrocytes have similar biomechanical properties (m:

from 4.562 to 7.892103

dyn/cm and hfrom 0.175 to

Address correspondence to Xiang Wang, College of Bioengineering, Chongqing University, Chongqing 400044, P.R. China.

E-mail: xwangchn@vip.sina.com

Artificial Cells, Blood Substitutes, and Biotechnology, 37: 4144

Copyright# 2009 Informa UK Ltd.

ISSN: 1073-1199 print / 1532-4184 online

DOI: 10.1080/10731190802674477

41

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TV

S*: Cell Suspension

Pressure Tank

Timer

Image

Recording

Image

Processing

Measuring

Image

Parameter

Calculating

Date Time

Pressure Recording

S*

Figure 1. Schematic drawing showing the system for micropipette aspiration.

P

Flowmeter

Pressure

BalanceOxygen

Saturation

analysis

SatO2

t

O2

CO2

N2

Figure 2. Dynamics analytical system of reconstruction erythrocyte carrying-releasing oxygen.

A

Figure 3A. The electron scanning microscope patterns of

reconstructed erythrocyte. 3040.

B

Figure 3B. The electron scanning microscope patterns of

reconstructed erythrocyte with different size. 5500.

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0.372104 dyn s/cm), having good deformability

(Table 1). The reconstructed erythrocyte demonstrated

greater resistance to osmotic lysis. The reconstructed

erythrocytes have carrying-releasing oxygen function.

The reconstructed erythrocytes blood can carry oxygen

(oxygen saturation reaching up to 86%) and can release

oxygen by alternatively being replaced with carbondioxide (oxygen saturation declining lowering down to

15%). Animal experimental results show that in hemor-

rhagic shock the reconstructed erythrocytes blood has a

good resuscitation function. The survival time of Wistar

rats was very near to that of rats receiving normal blood

(Figures 4 and 5, Table 2).

CONCLUSIONS

Biorheological properties of reconstructed erythrocytes

are closely related to the function of carrying-releasing

oxygen. The reconstructed erythrocytes with bioconcave

disc shape have oxygen carrying-releasing function and

good deformability. The study indicated the physiological

function of reconstructed erythrocyte was similar to that

of natural erythrocyte.

C

Figure 3C. The electron scanning microscope patterns of

reconstructed erythrocytes. 3800.

D

Figure 3D. The electron scanning microscope patterns of

reconstructed erythrocytes. 101.

Table 1. Biomechanical properties of reconstituted erythrocyte

based on Hemispherical cap model (from Chiens theory)

Elastic

modulus

(103dyn/

cm)

Viscous

coefficient

(104dyns/cm) S/V ratio

Reconstituted

RBC

4.567.89 0.180.37 1.481.53

Normal hRBC 1.128.75 0.190.45 1.391.44

0

10

20

30

40

50

60

70

80

90

0 2 3.6 6 8 10 12Time(min)

PO2%

saturation

dissociation

Figure 4. Dynamical curve of oxygen saturation-dissociation of reconstitute erythrocyte.

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ACKNOWLEDGEMENT

Dr. Xiang Wang was supported by National Natural

Science Foundation of China (NSFC 10572159). This

research is also partially supported by 111 Project

entitled Biomechanics & Tissue Repair Engineering (No.:

B06023) and Chongqing Science & Technology Council

(CSTC 2006ba5010).

REFERENCES

1. Chang, T.M (2000). Artificial cell biotechnology for medical

applications. Blood Purif:;18(2):916. Chang, T.M. (2002).

Artificial cells for artificial organs.Artif. Cells Blood Substit.

Immobil. Biotechnol.,30(5 & 6): 469497.

2. Cheung, Anthony T.W., Driessen, Bernd, Jahr, Jonathan S.,

Duong, Patricia L., Ramanujam, Sahana, Chen, Peter C. Y.

and Gunther, Robert A. (2004). Blood substitute resuscita-

tion as a treatment modality for moderate hypovolemia,Artif.

Cells Blood Substit. Immobil. Biotechnol, 32(2):189207.

3. Spahn, D.R., Pasch, T. (2001). Physiological properties of

blood substitutes. News Physiol Sci. 16:3841.4. Sung, K.L.P., Chien, S. (1977). Viscous and elastic proper-

ties of human red cell membrane. American Institute of

Chemical Engineers 18:54.

5. Sung, K.L.P., Chien, S. (1978). Viscous and elastic proper-

ties of human red cell membrane. The American Institute of

Chemical Engineers Symposium Series: Biorheology No.

18274:81.

6. Chien, S., Sung, K.L.P., Skalak, R., Usami, S., Tozeren, A.

(1978). Theoretical and experimental studies on viscoelastic

properties of erythrocyte membrane. Biophys. J24:463.

Table 2. Anti-hemorrhagic shock results of reconstituted

erythrocyte blood

Test

group Name of group

Mean survival

time (h)

A Reconstructed erythrocytes blood 15.290.2

B Wistar blood 17.590.3*

C Wistar erythrocyte saline 14.590.5

D Wistar blood plasma 9.890.4**

E Saline 3.890.6**

F Liposome of Hb 8.090.3**

G Hbsaline 6.090.5**

H Anti-shock drug 13.090.2*

Compared with C group *: 0.01BPB0.05, **: pB0.01

0

10

20

30

40

50

60

70

80

90

0 3.3 7 10 13

Time(min)

PO2%

saturation

dissociation

Figure 5. Dynamical curve of oxygen saturation-dissociation of Human blood.

This paper was first published online on iFirst on 16 January 2009.

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