INFECTION AND IMMUNrrY, June 1975, p. 1371-1374 Copyright 0 1975 American Society for Microbiology
Vol. 11, No. 6
Printed in U.S.A.
Systemic Amyloidosis in Mice Inoculated with Lyophilized Candida Cells STANLEY J. MANN* AND F. BLANK Skin and Cancer Hospital, Temple University Health Sciences Center, Philadelphia,
Pennsylvania 19140
Received for publication 20 January 1975
Injection of lyophilized Candida albicans or C. parapsilosis cells induced amyloidosis in outbred CFW mice. The disease process was irreversible, and a significant number of animals died of systemic amyloidosis within 400 days after the last treatment. The techniques described may represent a model system for the study of systemic amyloidosis.
Amyloidosis has been studied for over a century, but its etiology remains unknown. Amyloid deposits can occur spontaneously in many different species of animals or can be induced by a wide range of materials such as repeated inoculation with casein, bacteria, egg albumen, turpentine, or endotoxin from Escherichia coli (1, 2, 5-8, 10). Experimentally induced amyloidosis in laboratory animals may gradually regress or disappear from one or more organs once the causal agent is removed (5, 6, 11, 13). Recently, Pearsall and Lagunoff (9) reported that amyloidosis occurred in the majority of treated mice of one inbred strain at 2 weeks after a single injection of Candida albicans or Saccharomyces cerevisiae cells. A lower incidence of amyloidosis occurred in several other strains, usually later than 2 weeks after treatment. The results of the present study are in agreement with these findings (9); injections of C. albicans and C. parapsilosis cells into outbred mice induced amyloidosis. Moreover, our study showed that the disease process was irreversible. A highly significant number of animals died of systemic amyloidosis within 400 days after the last treatment. (A preliminary report of this work was presented at the First Annual Collaborative Conference, Carcinogenesis Program of the National Cancer Institute, October 1972.)
0.5% proteose peptone (Difco), 0.25% yeast extract (Difco), 0.1% KH,PO4, and 0.5% MgSO4.7H,O. The inoculated flasks were placed on a New Brunswick gyrotary shaker G25 operating at 60 rpm and incubated for 24 h at 37 C. The flasks were removed from the shaker and kept for 24 h at room temperature to allow the growth to sediment. The medium was decanted, 150 ml of fresh medium was added, and the flasks were again shaken for 24 h. Fresh medium was added a third time, and the cultures were grown for 24 h. The cells were collected by centrifugation. C. parapsilosis cells were killed by a mixture of acetone and methanol, washed with distilled water, and lyophilized. C. albicans cells were washed with distilled water and lyophilized. The harvested growth consisted of yeast cells only. Growth was obtained when lyophilized C. albicans cells were placed on Sabouraud glucose agar. The lyophilized cells were homogenized in a mortar with a pestle and suspended in tricaprylin (triolein, 99.9% pure) that was obtained from Drew Chemical Co., Booton, N.J. The injections (0.1 ml) were given subcutaneously into the inguinal area with sterile, disposable plastic syringes fitted with 25-guage needles. Each of 75 CFW mice was injected with a total of 90 mg of C. parapsilosis suspended in 1.0 ml of tricaprylin given in 10 injections of 0.1 ml during a period of 27 days. Similarly, 15 mice received 90 mg and 15 received 135 mg of C. albicans per 1.0 ml; one of the mice in the former group died during the period of treatment. Seventy-five mice were maintained as untreated controls; six animals died and were not included in the study. All mice in the experimental and control groups were weighed at the start of the experiments and then monthly throughout the period of obMATERIALS AND METHODS servation. Mice were observed thrice weekly. No infections were observed at the site of injection Animals. Eight-week-old female outbred CFW mice were obtained from Carworth Farms (Charles in any of the mice, including those treated with the River, Inc.), New York, N.Y. The animals, weighing viable C. albicans cells. Histopathology. Moribund animals were killed between 25 to 30 g, were housed eight animals and autopsied. All surviving mice were killed at 400 per cage and fed and watered ad libitum. Preparation of fungal cells. A suspension of C. days and autopsied. The spleen, kidney, liver, and albicans or C. parapsilosis was inoculated into 500-ml other abnormally appearing tissues such as lung were Erlenmeyer flasks containing 200 ml of medium. The removed and processed for histological examination. medium consisted of 5% cerelose (crude glucose), Blood smears, prepared from a sampling of moribund 1371
1372
MANN AND BLANK
mice, were treated with Wright stain. Histological sections were stained with hematoxylin and eosin, Congo red, and periodic acid-Schiff stain with diastase. All diagnoses of amyloidosis were based on histological examination. Animals that were not autopsied were not included in the data.
INFECT. IMMUN.
Amyloidosis was diagnosed as early as 27 days
after the last treatment in animals who received a total dose of 135 mg of C. albicans cells and 75 days after treatment with 90 mg of either C. albicans or C. parapsilosis cells. The results suggest that the course of the disease may depend upon the dose of the fungal cells inRESULTS jected into the mice. Most animals with amyloidosis could be recAmyloidosis was observed in 60 to 70% of the ognized prior to becoming moribund; the body mice treated with fungal cells, whereas 4.5 to was often turgid and the eyes had a pale glassy 5.5% of the untreated and tricaprylin control appearance. Frequently, animals were either animals were afflicted with amyloidosis (Table edematous or ascitic or both. Blood smears from 1). The incidence of amyloidosis may be higher moribund animals showed an increase in the than that shown in Table 1. number of leukocytes. The spleens were abnorThe survival rate of the animals in the groups mal, the liver mottled, and the cortical surface injected with lyophilized fungal cells was lower of the kidneys of many animals was pale, than that of the tricaprylin or untreated control blotchy, and diffusely granular. Moderate to groups. Only 17% of the animals treated with C. severe adhesions often occurred between various parapsilosis cells were alive at 400 days after organs or between an organ and the parietal treatment, which was significantly less than in peritoneum. the tricaprylin or untreated control groups (Fig. Deposits of amyloid were recognized readily 3). However, significantly fewer untreated conin the spleens (Fig. 1) and kidneys. Most trol animals survived to 400 days after treatanimals had deposits in the liver (Fig. 2). In ment than tricaprylin control animals (X2 = severely afflicted animals, amyloid was ob- 18.3, P < 0.05). The reason for a difference of served in the majority of internal organs includ- this magnitude between the two control groups ing heart and lung. Often, most of the normal is not known. structure of the spleen and liver was replaced by Similar results were obtained in the experiamyloid (Fig. 1 and 2). mental groups injected with two different doses a
A".._
A*
*
wo
t.
;
S SS
*
' 's,
vs 4br,
-z-,
'*
jAvx,
^
rF-q 4p'.,1, --
*
bs
7
f0 S
*
' f
lb
% -,em8
S A~~~. ~ ~ ~~~~~~ _4
_~~
*
1* v
.fr- "' 9.4 -
_
FIG. 1. Section showing masses of amyloid deposited in the liver of a mouse injected with C. parapsilosis cells. Hematoxylin and eosin.
VOL. 11, 1975
*S.
AMYLOIDOSIS IN MICE p
,i t
j
p
-
rJ
*
4± .
4, 9
N
',.
i*
I.
A
,
.
'
Is'
>
0,
-
#
q
..0 l
*
---r
*t
0,.
4
a
,
a
a
4w
,
.
V0 ,
.
Jr
0 .
10
9
VS0
T.t..-# ..._
.1
%
9
V.
LX£. .*
i
-
1373
e
El .9I U
a 0 .w
V 0
4
FIG. 2. Section of a spleen from a mouse injected with C. parapsilosis cells showing heavy deposits of amyloid. Hematoxylin and eosin. TABLE 1. Amyloidosis induced in mice with lyophilized Candida cells No. of mice
Treatment
No. of mice injected
No. of mice autopsied
Total dose (mg)a
amyloidosis
C. parapsilosis C. albicans C. albicans Untreated control Tricaprylin control
75 15 15 75 75
46
90
28
60.9
11 11
90 135
7 8
63.6 72.7
3 3
5.5 4.5
55 65
Percent
aTotal dose resulting from 10 equal treatments each suspended in 0.1 ml of tricaprylin.
of C. albicans cells. One of 15 animals injected with 90 mg in 1.0 ml of tricaprylin was alive 400 days after treatment, whereas none of 15 animals injected with 135 mg in 1.0 ml of tricaprylin survived to 400 days after treatment.
DISCUSSION Animals afflicted with amyloidosis became moribund from 27 days after the last inoculation to the termination of the experiment at 400 days. At 400 days, 8 of the 13 surviving mice treated with C. parapsilosis cells had deposits of amyloid. Such variability may be due partly to the mixed genetic background of the outbred CFW stock of mice. Moreover, a low percentage
of aged mice of the CFW stock developed "spontaneous" amyloidosis. Six of 120 untreated and tricaprylin control animals developed amyloidosis (Table 1); however, these animals were still alive 400 days after the last treatment. The frequency of amyloidosis is known to differ among inbred mouse strains inoculated with fungal cells (9). Pearsall and Lagunoff (9) observed that viable fungal cells were more effective in producing amyloidosis than killed cells. In the present study, systemic amyloidosis did not result from a mycotic infection. Fungal elements were not observed in histological sections of any autopsied animal. In a previous study, amyloidosis
1374
loot 80 E
60
QC
40
a)
02 20
~C
MANN AN]D BLANK
>_.N
-""F .~..M.".'. ._... ....
..........
TU capryld
control
Untreated Cp.......
5b0
control paraps,fos's
160
150
%wf
200
250
300
350
400
Days after last treatment
FIG. 3. Percentage of tricaprylin control (71 mice), untreated control (69 mice) and animals treated with C. parapsilosis cells (75 mice) surviving to 400 days after the last treatment. not observed in mice injected with extracts from several fungal species (3). These extracts did not include all the components of the cell wall. Cell wall components may be necessary for the induction of amyloidosis. Experimental amyloidosis in laboratory animals may regress or disappear from one or more organs once the causal agent is removed (5, 6, 11, 13). The course of the systemic amyloidosis described in the present study seems to parallel that described in man (4, 12). Limited deposits of amyloid are found frequently in aged humans, but the prognosis for systemic amyloidosis is unfavorable (4, 12). Part of the problem in determining or evaluating treatment for systemic amyloidosis in humans is the lack of a comparable experimental animal test system. The techniques described in the present study may therefore represent a model system for further studies of systemic amyloidosis. was
INFECT. IMMUN.
ACKNOWLEDGMENTS This study was supported by Public Health Service contract 1-CP-51209 and grant CA-11536 from the National Cancer Institute. We thank Bernice M. Branch for technical assistance and Gerald Pearlman for help in photography. Mice were maintained in facilities approved by the American Association for Accreditation of Laboratory Animal Care. LITERATURE CITED 1. Bailey, C. H. 1916. The production of amyloid disease and chronic nephritis in rabbits by repeated injections of living colon bacilli. J. Exp. Med. 23:773-790. 2. Barth, W., J. K. Gordon, and J. T. Willerson. 1968. Amyloidosis induced in mice by Escherichia coli endotoxin. Science 162:694-695. 3. Blank, F., 0. Chin, G. Just, D. R. Meranze, M. B. Shimkin, and R. Wieder. 1968. Carcinogens from fungi pathogenic for man. Cancer Res. 28:2276-2281. 4. Cohen, A. S., and A. A. Wills III. 1968. The incidence of amyloid deposits in 100 consecutive postmortem examinations, p. 438-445. In E. Mandema, L. Ruinen, J. H. Scholten, and A. S. Cohen (ed.), Amyloidosis. Excerpta Medica Foundation, Amsterdam. 5. DeLellis, R. A., J. S. Ram, and G. G. Glenner. 1970. Amyloid. IX. Further kinetic studies on experimental murine amyloidosis. Int. Arch. Allergy 37:175-183. 6. Dick, G. F., and L. Leiter. 1941. Some factors in the development, localization and reabsorption of experimental amyloidosis in the rabbit. Am. J. Pathol. 17:741-754. 7. Janigan, D. T. 1965. Experimental amyloidosis. Studies with a modified casein method, casein hydrolysate and gelatin. Am. J. Pathol. 47:159-171. 8. Kirkpatrick, J. B., and G. D. Sorenson. 1964. Murine amyloidosis induced by egg albumin. Lab. Invest. 13:954. 9. Pearsall, N. N., and D. Lagunoff. 1974. Immunological responses to Candida albicans. II. Amyloidosis in mice induced by candidiasis. Infect. Immun. 10:1397-1400. 10. Ram, J. S., R. A. DeLellis, and G. G. Glenner. 1968. Amyloid. III. A method for rapid induction of amyloidosis in mice. Int. Arch. Allergy 34:201-204. 11. Richter, G. W. 1954. The resorption of amyloid under experimental conditions. Am. J. Pathol. 30:239-261. 12. Symmers, W. St. C. 1956. Primary amyloidosis: a review. J. Clin. Pathol. 9:187-211. 13. Williams, G. 1967. Histological studies in the resorption of experimental amyloid. J. Pathol. Bacteriol. 94:331-336.
Vol. 11, No. 6
Printed in U.S.A.
Systemic Amyloidosis in Mice Inoculated with Lyophilized Candida Cells STANLEY J. MANN* AND F. BLANK Skin and Cancer Hospital, Temple University Health Sciences Center, Philadelphia,
Pennsylvania 19140
Received for publication 20 January 1975
Injection of lyophilized Candida albicans or C. parapsilosis cells induced amyloidosis in outbred CFW mice. The disease process was irreversible, and a significant number of animals died of systemic amyloidosis within 400 days after the last treatment. The techniques described may represent a model system for the study of systemic amyloidosis.
Amyloidosis has been studied for over a century, but its etiology remains unknown. Amyloid deposits can occur spontaneously in many different species of animals or can be induced by a wide range of materials such as repeated inoculation with casein, bacteria, egg albumen, turpentine, or endotoxin from Escherichia coli (1, 2, 5-8, 10). Experimentally induced amyloidosis in laboratory animals may gradually regress or disappear from one or more organs once the causal agent is removed (5, 6, 11, 13). Recently, Pearsall and Lagunoff (9) reported that amyloidosis occurred in the majority of treated mice of one inbred strain at 2 weeks after a single injection of Candida albicans or Saccharomyces cerevisiae cells. A lower incidence of amyloidosis occurred in several other strains, usually later than 2 weeks after treatment. The results of the present study are in agreement with these findings (9); injections of C. albicans and C. parapsilosis cells into outbred mice induced amyloidosis. Moreover, our study showed that the disease process was irreversible. A highly significant number of animals died of systemic amyloidosis within 400 days after the last treatment. (A preliminary report of this work was presented at the First Annual Collaborative Conference, Carcinogenesis Program of the National Cancer Institute, October 1972.)
0.5% proteose peptone (Difco), 0.25% yeast extract (Difco), 0.1% KH,PO4, and 0.5% MgSO4.7H,O. The inoculated flasks were placed on a New Brunswick gyrotary shaker G25 operating at 60 rpm and incubated for 24 h at 37 C. The flasks were removed from the shaker and kept for 24 h at room temperature to allow the growth to sediment. The medium was decanted, 150 ml of fresh medium was added, and the flasks were again shaken for 24 h. Fresh medium was added a third time, and the cultures were grown for 24 h. The cells were collected by centrifugation. C. parapsilosis cells were killed by a mixture of acetone and methanol, washed with distilled water, and lyophilized. C. albicans cells were washed with distilled water and lyophilized. The harvested growth consisted of yeast cells only. Growth was obtained when lyophilized C. albicans cells were placed on Sabouraud glucose agar. The lyophilized cells were homogenized in a mortar with a pestle and suspended in tricaprylin (triolein, 99.9% pure) that was obtained from Drew Chemical Co., Booton, N.J. The injections (0.1 ml) were given subcutaneously into the inguinal area with sterile, disposable plastic syringes fitted with 25-guage needles. Each of 75 CFW mice was injected with a total of 90 mg of C. parapsilosis suspended in 1.0 ml of tricaprylin given in 10 injections of 0.1 ml during a period of 27 days. Similarly, 15 mice received 90 mg and 15 received 135 mg of C. albicans per 1.0 ml; one of the mice in the former group died during the period of treatment. Seventy-five mice were maintained as untreated controls; six animals died and were not included in the study. All mice in the experimental and control groups were weighed at the start of the experiments and then monthly throughout the period of obMATERIALS AND METHODS servation. Mice were observed thrice weekly. No infections were observed at the site of injection Animals. Eight-week-old female outbred CFW mice were obtained from Carworth Farms (Charles in any of the mice, including those treated with the River, Inc.), New York, N.Y. The animals, weighing viable C. albicans cells. Histopathology. Moribund animals were killed between 25 to 30 g, were housed eight animals and autopsied. All surviving mice were killed at 400 per cage and fed and watered ad libitum. Preparation of fungal cells. A suspension of C. days and autopsied. The spleen, kidney, liver, and albicans or C. parapsilosis was inoculated into 500-ml other abnormally appearing tissues such as lung were Erlenmeyer flasks containing 200 ml of medium. The removed and processed for histological examination. medium consisted of 5% cerelose (crude glucose), Blood smears, prepared from a sampling of moribund 1371
1372
MANN AND BLANK
mice, were treated with Wright stain. Histological sections were stained with hematoxylin and eosin, Congo red, and periodic acid-Schiff stain with diastase. All diagnoses of amyloidosis were based on histological examination. Animals that were not autopsied were not included in the data.
INFECT. IMMUN.
Amyloidosis was diagnosed as early as 27 days
after the last treatment in animals who received a total dose of 135 mg of C. albicans cells and 75 days after treatment with 90 mg of either C. albicans or C. parapsilosis cells. The results suggest that the course of the disease may depend upon the dose of the fungal cells inRESULTS jected into the mice. Most animals with amyloidosis could be recAmyloidosis was observed in 60 to 70% of the ognized prior to becoming moribund; the body mice treated with fungal cells, whereas 4.5 to was often turgid and the eyes had a pale glassy 5.5% of the untreated and tricaprylin control appearance. Frequently, animals were either animals were afflicted with amyloidosis (Table edematous or ascitic or both. Blood smears from 1). The incidence of amyloidosis may be higher moribund animals showed an increase in the than that shown in Table 1. number of leukocytes. The spleens were abnorThe survival rate of the animals in the groups mal, the liver mottled, and the cortical surface injected with lyophilized fungal cells was lower of the kidneys of many animals was pale, than that of the tricaprylin or untreated control blotchy, and diffusely granular. Moderate to groups. Only 17% of the animals treated with C. severe adhesions often occurred between various parapsilosis cells were alive at 400 days after organs or between an organ and the parietal treatment, which was significantly less than in peritoneum. the tricaprylin or untreated control groups (Fig. Deposits of amyloid were recognized readily 3). However, significantly fewer untreated conin the spleens (Fig. 1) and kidneys. Most trol animals survived to 400 days after treatanimals had deposits in the liver (Fig. 2). In ment than tricaprylin control animals (X2 = severely afflicted animals, amyloid was ob- 18.3, P < 0.05). The reason for a difference of served in the majority of internal organs includ- this magnitude between the two control groups ing heart and lung. Often, most of the normal is not known. structure of the spleen and liver was replaced by Similar results were obtained in the experiamyloid (Fig. 1 and 2). mental groups injected with two different doses a
A".._
A*
*
wo
t.
;
S SS
*
' 's,
vs 4br,
-z-,
'*
jAvx,
^
rF-q 4p'.,1, --
*
bs
7
f0 S
*
' f
lb
% -,em8
S A~~~. ~ ~ ~~~~~~ _4
_~~
*
1* v
.fr- "' 9.4 -
_
FIG. 1. Section showing masses of amyloid deposited in the liver of a mouse injected with C. parapsilosis cells. Hematoxylin and eosin.
VOL. 11, 1975
*S.
AMYLOIDOSIS IN MICE p
,i t
j
p
-
rJ
*
4± .
4, 9
N
',.
i*
I.
A
,
.
'
Is'
>
0,
-
#
q
..0 l
*
---r
*t
0,.
4
a
,
a
a
4w
,
.
V0 ,
.
Jr
0 .
10
9
VS0
T.t..-# ..._
.1
%
9
V.
LX£. .*
i
-
1373
e
El .9I U
a 0 .w
V 0
4
FIG. 2. Section of a spleen from a mouse injected with C. parapsilosis cells showing heavy deposits of amyloid. Hematoxylin and eosin. TABLE 1. Amyloidosis induced in mice with lyophilized Candida cells No. of mice
Treatment
No. of mice injected
No. of mice autopsied
Total dose (mg)a
amyloidosis
C. parapsilosis C. albicans C. albicans Untreated control Tricaprylin control
75 15 15 75 75
46
90
28
60.9
11 11
90 135
7 8
63.6 72.7
3 3
5.5 4.5
55 65
Percent
aTotal dose resulting from 10 equal treatments each suspended in 0.1 ml of tricaprylin.
of C. albicans cells. One of 15 animals injected with 90 mg in 1.0 ml of tricaprylin was alive 400 days after treatment, whereas none of 15 animals injected with 135 mg in 1.0 ml of tricaprylin survived to 400 days after treatment.
DISCUSSION Animals afflicted with amyloidosis became moribund from 27 days after the last inoculation to the termination of the experiment at 400 days. At 400 days, 8 of the 13 surviving mice treated with C. parapsilosis cells had deposits of amyloid. Such variability may be due partly to the mixed genetic background of the outbred CFW stock of mice. Moreover, a low percentage
of aged mice of the CFW stock developed "spontaneous" amyloidosis. Six of 120 untreated and tricaprylin control animals developed amyloidosis (Table 1); however, these animals were still alive 400 days after the last treatment. The frequency of amyloidosis is known to differ among inbred mouse strains inoculated with fungal cells (9). Pearsall and Lagunoff (9) observed that viable fungal cells were more effective in producing amyloidosis than killed cells. In the present study, systemic amyloidosis did not result from a mycotic infection. Fungal elements were not observed in histological sections of any autopsied animal. In a previous study, amyloidosis
1374
loot 80 E
60
QC
40
a)
02 20
~C
MANN AN]D BLANK
>_.N
-""F .~..M.".'. ._... ....
..........
TU capryld
control
Untreated Cp.......
5b0
control paraps,fos's
160
150
%wf
200
250
300
350
400
Days after last treatment
FIG. 3. Percentage of tricaprylin control (71 mice), untreated control (69 mice) and animals treated with C. parapsilosis cells (75 mice) surviving to 400 days after the last treatment. not observed in mice injected with extracts from several fungal species (3). These extracts did not include all the components of the cell wall. Cell wall components may be necessary for the induction of amyloidosis. Experimental amyloidosis in laboratory animals may regress or disappear from one or more organs once the causal agent is removed (5, 6, 11, 13). The course of the systemic amyloidosis described in the present study seems to parallel that described in man (4, 12). Limited deposits of amyloid are found frequently in aged humans, but the prognosis for systemic amyloidosis is unfavorable (4, 12). Part of the problem in determining or evaluating treatment for systemic amyloidosis in humans is the lack of a comparable experimental animal test system. The techniques described in the present study may therefore represent a model system for further studies of systemic amyloidosis. was
INFECT. IMMUN.
ACKNOWLEDGMENTS This study was supported by Public Health Service contract 1-CP-51209 and grant CA-11536 from the National Cancer Institute. We thank Bernice M. Branch for technical assistance and Gerald Pearlman for help in photography. Mice were maintained in facilities approved by the American Association for Accreditation of Laboratory Animal Care. LITERATURE CITED 1. Bailey, C. H. 1916. The production of amyloid disease and chronic nephritis in rabbits by repeated injections of living colon bacilli. J. Exp. Med. 23:773-790. 2. Barth, W., J. K. Gordon, and J. T. Willerson. 1968. Amyloidosis induced in mice by Escherichia coli endotoxin. Science 162:694-695. 3. Blank, F., 0. Chin, G. Just, D. R. Meranze, M. B. Shimkin, and R. Wieder. 1968. Carcinogens from fungi pathogenic for man. Cancer Res. 28:2276-2281. 4. Cohen, A. S., and A. A. Wills III. 1968. The incidence of amyloid deposits in 100 consecutive postmortem examinations, p. 438-445. In E. Mandema, L. Ruinen, J. H. Scholten, and A. S. Cohen (ed.), Amyloidosis. Excerpta Medica Foundation, Amsterdam. 5. DeLellis, R. A., J. S. Ram, and G. G. Glenner. 1970. Amyloid. IX. Further kinetic studies on experimental murine amyloidosis. Int. Arch. Allergy 37:175-183. 6. Dick, G. F., and L. Leiter. 1941. Some factors in the development, localization and reabsorption of experimental amyloidosis in the rabbit. Am. J. Pathol. 17:741-754. 7. Janigan, D. T. 1965. Experimental amyloidosis. Studies with a modified casein method, casein hydrolysate and gelatin. Am. J. Pathol. 47:159-171. 8. Kirkpatrick, J. B., and G. D. Sorenson. 1964. Murine amyloidosis induced by egg albumin. Lab. Invest. 13:954. 9. Pearsall, N. N., and D. Lagunoff. 1974. Immunological responses to Candida albicans. II. Amyloidosis in mice induced by candidiasis. Infect. Immun. 10:1397-1400. 10. Ram, J. S., R. A. DeLellis, and G. G. Glenner. 1968. Amyloid. III. A method for rapid induction of amyloidosis in mice. Int. Arch. Allergy 34:201-204. 11. Richter, G. W. 1954. The resorption of amyloid under experimental conditions. Am. J. Pathol. 30:239-261. 12. Symmers, W. St. C. 1956. Primary amyloidosis: a review. J. Clin. Pathol. 9:187-211. 13. Williams, G. 1967. Histological studies in the resorption of experimental amyloid. J. Pathol. Bacteriol. 94:331-336.
