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Liposome targeting to mouse brain: Mannose as a recognition marker
Vo1,153, No, 3,1988 June 30,1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS Pages 1 038-1044
LIPOSOME TARGETING TO MOUSE BRAIN: RECOGNITION MARKER
MANNOSE AS A
Umezawa, F. and Eto, Y. Department of Pediatrics, Tokyo Jikei University School of Medicine, Minato-ku, Tokyo 105, Japan
Received May 3, 1988
SUMMARY: Liposomes prepared from lecithin:cholesterol:p-aminophenyl-alpha-mannoside (7:2:1, v/v/v) were efficiently incorporated into the mouse brain across the blood brain barrier. Furthermore, liposomes injected intraperitoneally were exclusively distributed into lysosome rich fraction and also taken up by glial cells. These data suggest that blood brain barrier cells and glial cells recognize mannose mblecule on the surface of the membrane and can be used for the treatment of brain damage by lysosomal storage disease. © 1988~ads~c Press, inc.
Lysosomal storage disease is caused by a certain lysosomal enzyme deficiency resulting in the storages of some complex carbohyrates and lipids in tissues of patients. Enzyme replacement therapy in these disorders is not successful for preventing or treating brain damage, since enzymes can not cross the blood brain barrier (1,2). It is known that most enzymes when injected as free proteins are quickly cleared from plasma and are taken up by liver and reticuloendoterial cells rather than being incorporated into specific organs or cells.(3,4). A number of alternate procedures for the treatment of lysosomal storage diseases such as bone marrow transplantation and liposomal therapy have been explored(5,6,7).
*Author to whom correspondence should be sent.
0006-291X/88 $1.50 Copyright O 1988 by Academic Press, Inc. All rights of reproduction in any form reserved.
1038
Vol. 153, No. 3, 1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Treatment by liposomes is one of the most promising procedures for delivering enzymes into brain cells across the blood brain barrier. In addition, treatment liposomes is of theoretical interest to identify recognition mechanism of liposomes by endothelial cells, glial cells or neuronal cells.
Many trials have been reported on the targeting of
liposomes into specific organs or cells(7,8,9). Coating some carbohydrates such as galactose, fucose and etc on the surface of liposomes has been used for delivery into specific organs(8,9). However, neither method can been used to introduce enzymes into the brain through the blood brain barrier. The present communication concerns the development of liposomes to target the brain using specific carbohydrate derivatives on the surface of liposomes. Specifically, mannose labeled liposomes were incorporated into the mouse brain, lysosomes and glial cells.
Materials and Methods
Materials; Phosphatidylcholine, p-aminophenyl glycoside(alpha-D-mannopyranoside,
alpha-L
or-D-fucopyranoside,beta-D-galactopyranoside,beta-D-glucopyranoside) and cholesterol were obtained from Sigma Chemical Co. USA. 3H-galactocerebroside was prepared as described by Suzuki et al. (I0). Preparation of liposomes; Liposomes were prepared from lecithin-cholesterol-p-aminophenyl-carbohydrates
(galactose, fucose
and mannose) 7:2:1, v/v/v. The liposomes were labeled with 3H-galactocerebroside as a surface marker. The preparation of llposomes was essentially carried out by the method described by Naoi et al. But briefly described as follows; these compounds were dissolved in chloroform-methanol
(2:l,v/v) and
dried in a rotary evaporator to make a film. And then 0.1M Tris-HCl
1039
Vol. 153, No. 3, 1 9 8 8
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
buffer was added and the liposome was stirred for 15 minutes and sonicated for 5 minutes in a water bath type sonicator. The suspension was centrifuged at 100,000 xg for 60 minutes and the washing was repeated twice and the pellet was dissolved in phosphate buffer(pH 7.5). Incorporation of liposomes into mice tissues:
The liposomes(0.bml)
(radioactivity 20x 104 cpm) were injected intraperitoneally into mice, (C57 black) and killed after 12, 24, 48 and 72 hours.
Each organ was
removed. The lipids were extracted and the radioactivity was measured. The subcellular fractionatlon of mouse brain and liver was carried out by the method of Clendenon et al(ll). The cell fractionation of brain cells was essentially performed by the method described by Sellinger et al(12).
Proteins were measured by Lowry et al.(13).
Results Fig. 1 shows the incorporation of 3H-galactocerebroside labeled liposomes prepared
from various aminophenyl derivatives into
normal mouse tissues such as brain, liver, spleen and kidney. The radiolabeled liposomes bearing aminophenyl-alpah-D-mannopyranoside were maximally incorporated into the mouse brain after 48 hours, whereas in the spleen and liver, these radioactivities were maximum after 12 hours. The mannose labeled liposomes were m o s t efficiently incorporated into the brain, while p-aminophenyl-beta-galactopyranoside
or alpah-D or
L-fucopyranoside labeled liposomes were crossed the blood brain barrier less efficiently.
The results of the subcellular
fractionation of mouse brain and liver after the intraperltoneal administration of liposomes labeled with amlnophenyl-alpha-mannoside are shown in Table I. In the brain, about 20 % to 30 % of total radioactivity was distributed in the mitochondria-lysosome fraction after 12 to 24 hours, whereas in the liver these radioactivities were 1040
Vol. 153, No. 3, 1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
BRAIN
LIVER
°t'
I0000 , /
0ooo
15000~ ,oooo
5000[ 1000
0
12 24
48
72 hour O" 12 24
KIDNEY
48
72 hour
SPLEEN
80000 ,90
60000 40000
0
I000 0
2000,
12 24 48 '72 hour 12 24 48 72 hour o--o:mannosederivatives D---O:galactosederivafivu
e---e:fucose derivativN (L-type)
Figure I.
IP--II:fucosederivaUv~ (D.type)
Incorporation of 3H-galactocerebroside labeled liposomes prepared from various a~Inophenyl glycoside derivatives into various normal mice tissues. -H-galactocerebroslde labeled llposomes (20 x 104 cmp) were injected into normal mice and radloactlvltles in each organ were chased after 12, 24, 48 and 72 hours.
40 to 36% after 12 to 24 hours, espectively. The maximum radioactivity in the brain was reached at 24 hours, while in the liver it was 12 hours. The incorporation rate in the brain was about 1/30 at 12 hours, i/5 at 24 hours, I/2 at 48 hours and 6/8 at 96 hours, as compared with
those of the liver. Table 2 shows the cellular distribution of the radiolabeled liposomes in the mouse brain. The cellular fraction in which liposomes were most incorporated was glial cells rather than neuronal cell. The greatest amount of radioactivity was found in the myelin fraction, however, this is probably due to co-migration of free llposomes with the myelin.
Discussion The present study demonstrates that liposomes containing aminophenyl mannoside were most efficiently incorporated into the
1041
Vol. 153, No. 3, 1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Table i. Time course and distribution of radioactivities in subcellular fractions of mice tissues after intraperitoneal injection of 3H-galactocerebroside labeled aminophenyl-mannoside containing liposomes
fraction Brain
12 hrs
2A hrs
48 hrs
96 hrs
(cpm/fraction)
Nucleus & Cell debris
99 (23.8%)
95 (5%)
44 (5.3%)
136 (21.0%)
Mitochondria & Lysosomes
80 (19.2%)
567 (30.2%)
156 (18.7%)
70 (10.8%)
Microsomes
40
Supernatant
Total
60
25
45
(9.6%)
(3.2%)
(3.0%)
(7.0%)
197 (47.4%)
1,156 (61.6%)
611 (73.0%)
396 (61.2%)
459
(1oo%)
1,878
836
(1oo%)
647
(1oo%)
(1oo%)
Liver (cpmlfraction)
Nucleus & Cell Debris
7,400 (41.6%)
1,380 (13.0%)
374 (22.0%)
88 (10.3%)
Mitochondria & Lysosomes
7,080 (39.9%)
3,855 (36.6%)
320 (18.8%)
121 (14.2%)
Microsomes
1,240
780
60
(7.0%)
(7.4%)
(3.5%)
2,034
4,532
945
625
(11.5%)
(43.0%)
(55.7%)
(73.2%)
17,754
10,547
1,699
(100%)
(100%)
(100%)
Supernatant Total
20
(2.3%)
854
(100%)
Aminophenyl-mannoside labeled liposomee (20x104 cpm) were injected into normal mice and mice were killed after 12, 24, 48 and 96 hours. Radioactivites of each fraction were expressed as cpm per brain. Parenthesis indicates percentage distribution of radioactive galactocerebroside in subcellular fraction.
mouse brain across the blood brain barrier, while other carbohydrate compounds such as fucose (D-type) and galactose were not as well incorporated
into
the brain.
These data
suggest
that
mannose can be
recognized by the cells of the blood brain barrier. Recently, carbohydrate mediated recognition systems by specific cells have been well accepted. The survival of the glycoprotein in circulation is determined largely by the nature of the exposed or 1042
Vol. 153, No. 3, 1 9 8 8
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Table 2. Time course and cellular distribution of 3H-galactocerebroside radioactivity in cellular fraction of mice brain after intraperltoneal injection of aminophenyl-mannoslde labeled liposomes
fraction
24 hrs
48 hrs
72 hrs
Neuron
1,080 (13.9%)
34 (5.1%)
61 (6.8%)
Glia
2,030 (26.1%)
344 (52.1%)
266 (29.5%)
882 (11.3%)
110 (16.6%)
280 (31.1%)
Neuron & Capillary Crude Myelin
3,787 (48.7%)
173 (26.2%) "
296 (32.7%)
Total
7,779 (100 %)
661 (I00 %)
903 (100 X)
Values are expressed as radloactivlties of each cellular fraction obtained from a mouse brain. Amlnophenyl-mannoside containing llposomes labeled with 3H-galactocerebroslde ( 20x 104 cpm) were injected intraperltoneally and mice were killed after 24j 48 and 72 hours. The radloactivitles were measured in glla, neuron, neuron & capillary and crude myelin fraction isolated as described by Selllnger et al.(13). Parenthesis indicates percentage distribution of radioactive 3Hgalactocerebroslde in each cellular fraction.
terminal sugar residues of the carbohydrate chain(Ashwell et al, 1974)(14)o
Stahl et al.(15) in 1978 reported the presence of mannose
receptors on cells of the reticuloendotherlal system of the rat, including the liver Kupffer cells and alveolar macrophages. However, the incorporation of liposomes by the brain cells has not been studied.
The subcellular fractionation study indicates that mannose
labeled llposomes are incorporated into lysosomes rich fraction both in liver and brain. Thus, alpha-mannosylated llposomes can selectively target llposome-entrapped biological active molecules toward different cell types and into lysosomes for digestion.
According to Yagi et ai.(16),
sulfatide containing liposomes were able to pass the blood brain barrier. However, on the basis of our experiment in twitcher mice, this llposome could not be transfered into the brain. Our study also demonstrates that liposomes containing aminophenylmannoslde are incorporated predominantly into glial cells rather than neuronal cells. These data suggest that gllal cells recognize mannose and posses the receptor.
1043
Vol. 153, No. 3, 1 9 8 8
BIOCHEMICAL AND BIOPHYSICALRESEARCH COMMUNICATIONS
Currently, we are studying the types of glial cells involved and the processes of endocytosls of liposomes. These basic studies may contribute to the possible treatment of the brain damage of lysosomal storage diseases.
References
i. Austin et al. (1967) in "Inborn Errors of Sphingolipid Metabolism" (S.M.Aronson and B.W. Volk eds.) pp 359-387, Pergamon. 2. Tager JM et al (1980) in "Enzyme therapy in genetic disease II) (R.J. Desnick eds), pp 393, Alan R. Liss, New York. 3. Brady RO, Barranger JA, Furbish FS, Munay GJ, Stowens D., Ginss EI (1982) in Advances in treatment of Inborn Error of Metabolism (M.D. Grawfurd, DA Gibbs and RWE Watts eds) pp 53-63, John Wiley and Son LTd, London. 4. Wakin KG, Flelscher GA (1963) J. Lab. Clin. Med. 61, 107-119. 5. Hobbs et ai.(1981) Lancet 2, 709-712. 6. ~mapperport JM, Ginn El (1984) New Engl. J. Med. 311, 84-88. 7. Gregorladls G, Neerunjum DE (1975) Biochem. Biophys. Res. Commun. 65: 537-544. 8. Surolia A., Bachhawat BK (1977) Biochem. Biophys. Acta 497, 760-765. 9. Jonah MM, Cerny EA, Rahman YE (1978) Biochem. Biophys. Acta 541, 321-333. 10. Suzuki K, Suzuki Y. (1970) Proc. Natl. Acad. Sci. USA 66, 302-309. ii. Naoi M., Yagl K. (1980) Biochem. Int. I, 591-596. 12. Clendenon N-K, Allen N. (1970) J. Neurochem. 17, 749-757. 13. Sellinnger OZ, Azcurra JM, Johnmson DE, Ohlsson WG, Lodln Z. (1971) Nature, New Biology, 230, 253-256. 14. Lowry OH, Kosebrough NJ, Farr AL, Randall RJ (1951) J. Biol. Chem. 193, 265-275. 15. Ashwell G., Morell AG (1977) Trends in Biochem. Sci. 2, 76-78. 16. Stahl PD, Rodman JS, Miller MJ, Schlesinger PH (1978) Proc. Natl. Acad. Sci, USA 75, 1399-1403. 17. Yagl K, Naol M, Sakai H, Abe H (1982) J. Appl.Biochem. 4, 121-125.
1044
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS Pages 1 038-1044
LIPOSOME TARGETING TO MOUSE BRAIN: RECOGNITION MARKER
MANNOSE AS A
Umezawa, F. and Eto, Y. Department of Pediatrics, Tokyo Jikei University School of Medicine, Minato-ku, Tokyo 105, Japan
Received May 3, 1988
SUMMARY: Liposomes prepared from lecithin:cholesterol:p-aminophenyl-alpha-mannoside (7:2:1, v/v/v) were efficiently incorporated into the mouse brain across the blood brain barrier. Furthermore, liposomes injected intraperitoneally were exclusively distributed into lysosome rich fraction and also taken up by glial cells. These data suggest that blood brain barrier cells and glial cells recognize mannose mblecule on the surface of the membrane and can be used for the treatment of brain damage by lysosomal storage disease. © 1988~ads~c Press, inc.
Lysosomal storage disease is caused by a certain lysosomal enzyme deficiency resulting in the storages of some complex carbohyrates and lipids in tissues of patients. Enzyme replacement therapy in these disorders is not successful for preventing or treating brain damage, since enzymes can not cross the blood brain barrier (1,2). It is known that most enzymes when injected as free proteins are quickly cleared from plasma and are taken up by liver and reticuloendoterial cells rather than being incorporated into specific organs or cells.(3,4). A number of alternate procedures for the treatment of lysosomal storage diseases such as bone marrow transplantation and liposomal therapy have been explored(5,6,7).
*Author to whom correspondence should be sent.
0006-291X/88 $1.50 Copyright O 1988 by Academic Press, Inc. All rights of reproduction in any form reserved.
1038
Vol. 153, No. 3, 1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Treatment by liposomes is one of the most promising procedures for delivering enzymes into brain cells across the blood brain barrier. In addition, treatment liposomes is of theoretical interest to identify recognition mechanism of liposomes by endothelial cells, glial cells or neuronal cells.
Many trials have been reported on the targeting of
liposomes into specific organs or cells(7,8,9). Coating some carbohydrates such as galactose, fucose and etc on the surface of liposomes has been used for delivery into specific organs(8,9). However, neither method can been used to introduce enzymes into the brain through the blood brain barrier. The present communication concerns the development of liposomes to target the brain using specific carbohydrate derivatives on the surface of liposomes. Specifically, mannose labeled liposomes were incorporated into the mouse brain, lysosomes and glial cells.
Materials and Methods
Materials; Phosphatidylcholine, p-aminophenyl glycoside(alpha-D-mannopyranoside,
alpha-L
or-D-fucopyranoside,beta-D-galactopyranoside,beta-D-glucopyranoside) and cholesterol were obtained from Sigma Chemical Co. USA. 3H-galactocerebroside was prepared as described by Suzuki et al. (I0). Preparation of liposomes; Liposomes were prepared from lecithin-cholesterol-p-aminophenyl-carbohydrates
(galactose, fucose
and mannose) 7:2:1, v/v/v. The liposomes were labeled with 3H-galactocerebroside as a surface marker. The preparation of llposomes was essentially carried out by the method described by Naoi et al. But briefly described as follows; these compounds were dissolved in chloroform-methanol
(2:l,v/v) and
dried in a rotary evaporator to make a film. And then 0.1M Tris-HCl
1039
Vol. 153, No. 3, 1 9 8 8
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
buffer was added and the liposome was stirred for 15 minutes and sonicated for 5 minutes in a water bath type sonicator. The suspension was centrifuged at 100,000 xg for 60 minutes and the washing was repeated twice and the pellet was dissolved in phosphate buffer(pH 7.5). Incorporation of liposomes into mice tissues:
The liposomes(0.bml)
(radioactivity 20x 104 cpm) were injected intraperitoneally into mice, (C57 black) and killed after 12, 24, 48 and 72 hours.
Each organ was
removed. The lipids were extracted and the radioactivity was measured. The subcellular fractionatlon of mouse brain and liver was carried out by the method of Clendenon et al(ll). The cell fractionation of brain cells was essentially performed by the method described by Sellinger et al(12).
Proteins were measured by Lowry et al.(13).
Results Fig. 1 shows the incorporation of 3H-galactocerebroside labeled liposomes prepared
from various aminophenyl derivatives into
normal mouse tissues such as brain, liver, spleen and kidney. The radiolabeled liposomes bearing aminophenyl-alpah-D-mannopyranoside were maximally incorporated into the mouse brain after 48 hours, whereas in the spleen and liver, these radioactivities were maximum after 12 hours. The mannose labeled liposomes were m o s t efficiently incorporated into the brain, while p-aminophenyl-beta-galactopyranoside
or alpah-D or
L-fucopyranoside labeled liposomes were crossed the blood brain barrier less efficiently.
The results of the subcellular
fractionation of mouse brain and liver after the intraperltoneal administration of liposomes labeled with amlnophenyl-alpha-mannoside are shown in Table I. In the brain, about 20 % to 30 % of total radioactivity was distributed in the mitochondria-lysosome fraction after 12 to 24 hours, whereas in the liver these radioactivities were 1040
Vol. 153, No. 3, 1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
BRAIN
LIVER
°t'
I0000 , /
0ooo
15000~ ,oooo
5000[ 1000
0
12 24
48
72 hour O" 12 24
KIDNEY
48
72 hour
SPLEEN
80000 ,90
60000 40000
0
I000 0
2000,
12 24 48 '72 hour 12 24 48 72 hour o--o:mannosederivatives D---O:galactosederivafivu
e---e:fucose derivativN (L-type)
Figure I.
IP--II:fucosederivaUv~ (D.type)
Incorporation of 3H-galactocerebroside labeled liposomes prepared from various a~Inophenyl glycoside derivatives into various normal mice tissues. -H-galactocerebroslde labeled llposomes (20 x 104 cmp) were injected into normal mice and radloactlvltles in each organ were chased after 12, 24, 48 and 72 hours.
40 to 36% after 12 to 24 hours, espectively. The maximum radioactivity in the brain was reached at 24 hours, while in the liver it was 12 hours. The incorporation rate in the brain was about 1/30 at 12 hours, i/5 at 24 hours, I/2 at 48 hours and 6/8 at 96 hours, as compared with
those of the liver. Table 2 shows the cellular distribution of the radiolabeled liposomes in the mouse brain. The cellular fraction in which liposomes were most incorporated was glial cells rather than neuronal cell. The greatest amount of radioactivity was found in the myelin fraction, however, this is probably due to co-migration of free llposomes with the myelin.
Discussion The present study demonstrates that liposomes containing aminophenyl mannoside were most efficiently incorporated into the
1041
Vol. 153, No. 3, 1988
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Table i. Time course and distribution of radioactivities in subcellular fractions of mice tissues after intraperitoneal injection of 3H-galactocerebroside labeled aminophenyl-mannoside containing liposomes
fraction Brain
12 hrs
2A hrs
48 hrs
96 hrs
(cpm/fraction)
Nucleus & Cell debris
99 (23.8%)
95 (5%)
44 (5.3%)
136 (21.0%)
Mitochondria & Lysosomes
80 (19.2%)
567 (30.2%)
156 (18.7%)
70 (10.8%)
Microsomes
40
Supernatant
Total
60
25
45
(9.6%)
(3.2%)
(3.0%)
(7.0%)
197 (47.4%)
1,156 (61.6%)
611 (73.0%)
396 (61.2%)
459
(1oo%)
1,878
836
(1oo%)
647
(1oo%)
(1oo%)
Liver (cpmlfraction)
Nucleus & Cell Debris
7,400 (41.6%)
1,380 (13.0%)
374 (22.0%)
88 (10.3%)
Mitochondria & Lysosomes
7,080 (39.9%)
3,855 (36.6%)
320 (18.8%)
121 (14.2%)
Microsomes
1,240
780
60
(7.0%)
(7.4%)
(3.5%)
2,034
4,532
945
625
(11.5%)
(43.0%)
(55.7%)
(73.2%)
17,754
10,547
1,699
(100%)
(100%)
(100%)
Supernatant Total
20
(2.3%)
854
(100%)
Aminophenyl-mannoside labeled liposomee (20x104 cpm) were injected into normal mice and mice were killed after 12, 24, 48 and 96 hours. Radioactivites of each fraction were expressed as cpm per brain. Parenthesis indicates percentage distribution of radioactive galactocerebroside in subcellular fraction.
mouse brain across the blood brain barrier, while other carbohydrate compounds such as fucose (D-type) and galactose were not as well incorporated
into
the brain.
These data
suggest
that
mannose can be
recognized by the cells of the blood brain barrier. Recently, carbohydrate mediated recognition systems by specific cells have been well accepted. The survival of the glycoprotein in circulation is determined largely by the nature of the exposed or 1042
Vol. 153, No. 3, 1 9 8 8
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Table 2. Time course and cellular distribution of 3H-galactocerebroside radioactivity in cellular fraction of mice brain after intraperltoneal injection of aminophenyl-mannoslde labeled liposomes
fraction
24 hrs
48 hrs
72 hrs
Neuron
1,080 (13.9%)
34 (5.1%)
61 (6.8%)
Glia
2,030 (26.1%)
344 (52.1%)
266 (29.5%)
882 (11.3%)
110 (16.6%)
280 (31.1%)
Neuron & Capillary Crude Myelin
3,787 (48.7%)
173 (26.2%) "
296 (32.7%)
Total
7,779 (100 %)
661 (I00 %)
903 (100 X)
Values are expressed as radloactivlties of each cellular fraction obtained from a mouse brain. Amlnophenyl-mannoside containing llposomes labeled with 3H-galactocerebroslde ( 20x 104 cpm) were injected intraperltoneally and mice were killed after 24j 48 and 72 hours. The radloactivitles were measured in glla, neuron, neuron & capillary and crude myelin fraction isolated as described by Selllnger et al.(13). Parenthesis indicates percentage distribution of radioactive 3Hgalactocerebroslde in each cellular fraction.
terminal sugar residues of the carbohydrate chain(Ashwell et al, 1974)(14)o
Stahl et al.(15) in 1978 reported the presence of mannose
receptors on cells of the reticuloendotherlal system of the rat, including the liver Kupffer cells and alveolar macrophages. However, the incorporation of liposomes by the brain cells has not been studied.
The subcellular fractionation study indicates that mannose
labeled llposomes are incorporated into lysosomes rich fraction both in liver and brain. Thus, alpha-mannosylated llposomes can selectively target llposome-entrapped biological active molecules toward different cell types and into lysosomes for digestion.
According to Yagi et ai.(16),
sulfatide containing liposomes were able to pass the blood brain barrier. However, on the basis of our experiment in twitcher mice, this llposome could not be transfered into the brain. Our study also demonstrates that liposomes containing aminophenylmannoslde are incorporated predominantly into glial cells rather than neuronal cells. These data suggest that gllal cells recognize mannose and posses the receptor.
1043
Vol. 153, No. 3, 1 9 8 8
BIOCHEMICAL AND BIOPHYSICALRESEARCH COMMUNICATIONS
Currently, we are studying the types of glial cells involved and the processes of endocytosls of liposomes. These basic studies may contribute to the possible treatment of the brain damage of lysosomal storage diseases.
References
i. Austin et al. (1967) in "Inborn Errors of Sphingolipid Metabolism" (S.M.Aronson and B.W. Volk eds.) pp 359-387, Pergamon. 2. Tager JM et al (1980) in "Enzyme therapy in genetic disease II) (R.J. Desnick eds), pp 393, Alan R. Liss, New York. 3. Brady RO, Barranger JA, Furbish FS, Munay GJ, Stowens D., Ginss EI (1982) in Advances in treatment of Inborn Error of Metabolism (M.D. Grawfurd, DA Gibbs and RWE Watts eds) pp 53-63, John Wiley and Son LTd, London. 4. Wakin KG, Flelscher GA (1963) J. Lab. Clin. Med. 61, 107-119. 5. Hobbs et ai.(1981) Lancet 2, 709-712. 6. ~mapperport JM, Ginn El (1984) New Engl. J. Med. 311, 84-88. 7. Gregorladls G, Neerunjum DE (1975) Biochem. Biophys. Res. Commun. 65: 537-544. 8. Surolia A., Bachhawat BK (1977) Biochem. Biophys. Acta 497, 760-765. 9. Jonah MM, Cerny EA, Rahman YE (1978) Biochem. Biophys. Acta 541, 321-333. 10. Suzuki K, Suzuki Y. (1970) Proc. Natl. Acad. Sci. USA 66, 302-309. ii. Naoi M., Yagl K. (1980) Biochem. Int. I, 591-596. 12. Clendenon N-K, Allen N. (1970) J. Neurochem. 17, 749-757. 13. Sellinnger OZ, Azcurra JM, Johnmson DE, Ohlsson WG, Lodln Z. (1971) Nature, New Biology, 230, 253-256. 14. Lowry OH, Kosebrough NJ, Farr AL, Randall RJ (1951) J. Biol. Chem. 193, 265-275. 15. Ashwell G., Morell AG (1977) Trends in Biochem. Sci. 2, 76-78. 16. Stahl PD, Rodman JS, Miller MJ, Schlesinger PH (1978) Proc. Natl. Acad. Sci, USA 75, 1399-1403. 17. Yagl K, Naol M, Sakai H, Abe H (1982) J. Appl.Biochem. 4, 121-125.
1044