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Influence of splenectomy on the development of leukemia in male mice of the ICRC strain
Life Sciences Vol. 10, Part II, pp. 475-479, 1971 . Printed in Great Britain
Pergamon Press
INFLUENCE OF SPLEIMTOMY ON THE DEVELOPMEIPP OF LEUKEMIA IN MALE MICE OF THE ICRC STRAIN S . R. Pai and Kamal J. Ranadive Biology Division, Cancer Research Institute, Tata Memorial Centre, Parel, Bombay 12, India
(Received 10 February 1971; in final form 25 March 1971) âummary
The spleen has been implicated in the development of spontaneous leukemia in the ICRC strain of mice . Removal of the spleen does not reduce the incidence of leukemia in these mice . Splenectomy, following inoculation of leukemic cells, did not suppress the disease . It appears that organs other than the spleen are involved in the development of the leukemia . The failure of splenectcmized mice to develop leukemia when implanted with leakemic cells cannot be explained. It has been reported that in ARR and irradiated C57BL leukemic mice, in which the thymus was mostly involved, thymectomy, but not splenectomy, was effective in the control of the disease in these mice (1,2) .
In the ICRC strain of mice
we observed the involvement of the spleen in most of the leukemic mice that developed. spontaneous leukemia .
Prepuberal splenectamy was, therefore, per-
formed on male mice to study the development of leukemia end this aspect of the study is discussed in the present communication . Materials and Methods spontaneous lymphocytic neoplasm, the localized and generalized types, develop in intact male and female mice of the ICRC strain between the ages of 10 to 16 months .
Both the sexes are equally susceptible to this disease .
Forty randomly selected weanling male mice, between the 18th and 20th generation, were used. as experimental animals .
Splenectos~y was performed on 20
males under ether anesthesia by -k_inw a one-half inch dorsal incision in the left flank region parallel to the ribs .
The remaining 20 males were kept as
nonoperated-litter-mate controls . An homogenate of leukemic spleen from one of the experimental females of the ICRC strain was prepared in normal saline at 1%, concentration (w/v) . A
475
476
Splenectomy and Leukemia,
group of
Vol. 10, No. 8
6 eight-week-old intact and splenectcmized ICRC males received an
intraperitoneal inoculation of this homogenate .
The injected animals were ob-
served for "tumor takes" . In another group intact males received first an intraperitoneal injection of l eukemi c spleen homogenate and splenectagy followed. after the tumors were palpable .
The control and experimental groups were kept under observation and
were killed when moribund The affected organs were studied for histological changes .
The forma in -fixed tissues were stained with hematoxylin and eosin.
Blood counts were not taken; however, blood and bone marrow smears were prepared at autopsy and were stained by Giemsa after methanol fixation . Results The results of the experiments are summarized in Table 1.
Of the twenty
TABLE 1 Summary of the Observations on Intact and Splenectemized ICRC Male Mice Age at Death (in months)
Type of Mouse* I. ii .
III .
Control Splenectamty
Control + Transplant Splenectomy + Transplant
Observations
(20)
(30)
11 to 20 9 to 19
1 lymphocytec leukemia 3 lymphosarccma
(6)
3 to 4
6/6 lymphocytec leukemia
(6)
8 to 10
0/6 no leukemia
Transplant followed by (3) 3 to 4 No remissions Splenectomy 3/3 lyMPh0C tic leukemia Figures in parentheses represent the numiber of mice used for each group.
control males one developed a generalized lymphocytec leukemia at and 3 out of 20 splenectcmized males developed lymphosarccma at
14 .5 months,
9, 11 and 13
months - the localized lymphocytec neoplasm according to Dunn (3) .
At the time
of autopsy the blood smears of the control and splenectcmized males showed a number of lymphocytes (Fig . 1) and the bane marrow was full of blast cells (Fig . 2) .
The tremendous lymphocytec and lymphoblastic infiltration was seen
in the liver (Fig . 3) and kidney (Fig . 4) .
Vol. 10, No . 8
477
Splenectomy and Leukemia
Tissues from Splenectomized ICRC Male Mice with Lymphosarcoms,
Fig. l. Lymphocytes in the peripheral blood . Giemsa X920 .
Fig. 2. Blast ceIIS in the bone marrow smear . Giemsa X920 .
Fig. 3. Lymphocytes diffusely scattered Fig. 4 . Lymphocytic infiltration in the in the sinusoids of the liver. kidney . H & E X460 . H & E X460 .
478
Splenectomy and Leukemia
Vol. 10, No. 8
None of the splenectamized males developed leukemia following a transplant of leukemic spleen cells, whereas controls developed leukemia .
6
out of
6
nonoperated-litter-mate
These results were reproduced in a second
experiment using two splenectomized and intact ICRC male mice, although the spleen homogenate was prepared from mice of the second generation . Splenectomy, after the advancement of the transplanted lesion as judged from the palpable spleens, had no prophylactic effect on the hosts as all the transplanted animals died of leukemia one week after the operation. Discussion In order to remove one pf the susceptible foci in the development of leukemia, splenectomy was performed on weanling ICRC males which are susceptible to spontaneous leukemia .
The observation of localized lymphocytec neoplasm in
15% (3/20) of the splenectcmized mice and a solitary generalized lymphocytec neoplasm in a control male suggest that splenectcany was unable to control the leukemia development .
It seems that the spleen, being one of the important
hemopoietic organs carrying out the twofold func tions of the production of lymphocytes in white pulp and. the filtration of blood in red pulp, if removed, exerts a stress on the lympho-hemopoietic organs which have to carry the function(s) of the missing spleen .
Kalpaktsoglou et al . (4) found an increase
in the number of circulating lymphocytes in prepuberally splenectamized C3H(Bi) mice, however, no case of leukemia was observed in these mice (personal communication) . The value of splenectomy in chronic myeloid leukemia has been questioned as the patients developed progressive anemia, pancytopenia and myeofibrotic bone marrow (5) .
In chronic lymphocytec leukemia splenectcm~y is often con
sidered along with steroid therapy, however, the routine use of this procedure is disfavored because of the fatal condition of the disease (6) .
The present
data further confirmed that splenectamy alone failed to help the remission of the disease induced by transplantation of leukemic spleen .
The failure of the
"tumor takes" in splenectamized males, however, is difficult to explain.
Vol . 10, No. 8
Splenectomy and Leukemia
479
Acknowledents The technical assistance of Mr . B. A . Dhopte and Mr . R . S . Dolas is gratefully acknowledged ; and it is a pleasure to express our appreciation to Mr . R. Y. Nerurkar . References
4, 377 (1944) .
1.
D. P. McEndy, M. C . Boon and J . Furth, Cancer Res.
2.
H. D. Kaplan, J. Natl Cancer Inst . 11,
3.
T. M. Dunn, J. Natl Cancer Inst .
4.
P . K. Kalpaktsoglou, E. J. Yunis and R . J. Good, Anat . Rec .
5.
A. Leranto, Duodecim
6.
W. Dameshek and T . Gunz, Leukemia (Gruse and Stratten, eds), P
114 , 1281 (1954) .
(1968) .
392,
83 (1950) . 160, 781
81, 482 (1965) .
New York and London
(1960) .
356
and
Pergamon Press
INFLUENCE OF SPLEIMTOMY ON THE DEVELOPMEIPP OF LEUKEMIA IN MALE MICE OF THE ICRC STRAIN S . R. Pai and Kamal J. Ranadive Biology Division, Cancer Research Institute, Tata Memorial Centre, Parel, Bombay 12, India
(Received 10 February 1971; in final form 25 March 1971) âummary
The spleen has been implicated in the development of spontaneous leukemia in the ICRC strain of mice . Removal of the spleen does not reduce the incidence of leukemia in these mice . Splenectomy, following inoculation of leukemic cells, did not suppress the disease . It appears that organs other than the spleen are involved in the development of the leukemia . The failure of splenectcmized mice to develop leukemia when implanted with leakemic cells cannot be explained. It has been reported that in ARR and irradiated C57BL leukemic mice, in which the thymus was mostly involved, thymectomy, but not splenectomy, was effective in the control of the disease in these mice (1,2) .
In the ICRC strain of mice
we observed the involvement of the spleen in most of the leukemic mice that developed. spontaneous leukemia .
Prepuberal splenectamy was, therefore, per-
formed on male mice to study the development of leukemia end this aspect of the study is discussed in the present communication . Materials and Methods spontaneous lymphocytic neoplasm, the localized and generalized types, develop in intact male and female mice of the ICRC strain between the ages of 10 to 16 months .
Both the sexes are equally susceptible to this disease .
Forty randomly selected weanling male mice, between the 18th and 20th generation, were used. as experimental animals .
Splenectos~y was performed on 20
males under ether anesthesia by -k_inw a one-half inch dorsal incision in the left flank region parallel to the ribs .
The remaining 20 males were kept as
nonoperated-litter-mate controls . An homogenate of leukemic spleen from one of the experimental females of the ICRC strain was prepared in normal saline at 1%, concentration (w/v) . A
475
476
Splenectomy and Leukemia,
group of
Vol. 10, No. 8
6 eight-week-old intact and splenectcmized ICRC males received an
intraperitoneal inoculation of this homogenate .
The injected animals were ob-
served for "tumor takes" . In another group intact males received first an intraperitoneal injection of l eukemi c spleen homogenate and splenectagy followed. after the tumors were palpable .
The control and experimental groups were kept under observation and
were killed when moribund The affected organs were studied for histological changes .
The forma in -fixed tissues were stained with hematoxylin and eosin.
Blood counts were not taken; however, blood and bone marrow smears were prepared at autopsy and were stained by Giemsa after methanol fixation . Results The results of the experiments are summarized in Table 1.
Of the twenty
TABLE 1 Summary of the Observations on Intact and Splenectemized ICRC Male Mice Age at Death (in months)
Type of Mouse* I. ii .
III .
Control Splenectamty
Control + Transplant Splenectomy + Transplant
Observations
(20)
(30)
11 to 20 9 to 19
1 lymphocytec leukemia 3 lymphosarccma
(6)
3 to 4
6/6 lymphocytec leukemia
(6)
8 to 10
0/6 no leukemia
Transplant followed by (3) 3 to 4 No remissions Splenectomy 3/3 lyMPh0C tic leukemia Figures in parentheses represent the numiber of mice used for each group.
control males one developed a generalized lymphocytec leukemia at and 3 out of 20 splenectcmized males developed lymphosarccma at
14 .5 months,
9, 11 and 13
months - the localized lymphocytec neoplasm according to Dunn (3) .
At the time
of autopsy the blood smears of the control and splenectcmized males showed a number of lymphocytes (Fig . 1) and the bane marrow was full of blast cells (Fig . 2) .
The tremendous lymphocytec and lymphoblastic infiltration was seen
in the liver (Fig . 3) and kidney (Fig . 4) .
Vol. 10, No . 8
477
Splenectomy and Leukemia
Tissues from Splenectomized ICRC Male Mice with Lymphosarcoms,
Fig. l. Lymphocytes in the peripheral blood . Giemsa X920 .
Fig. 2. Blast ceIIS in the bone marrow smear . Giemsa X920 .
Fig. 3. Lymphocytes diffusely scattered Fig. 4 . Lymphocytic infiltration in the in the sinusoids of the liver. kidney . H & E X460 . H & E X460 .
478
Splenectomy and Leukemia
Vol. 10, No. 8
None of the splenectamized males developed leukemia following a transplant of leukemic spleen cells, whereas controls developed leukemia .
6
out of
6
nonoperated-litter-mate
These results were reproduced in a second
experiment using two splenectomized and intact ICRC male mice, although the spleen homogenate was prepared from mice of the second generation . Splenectomy, after the advancement of the transplanted lesion as judged from the palpable spleens, had no prophylactic effect on the hosts as all the transplanted animals died of leukemia one week after the operation. Discussion In order to remove one pf the susceptible foci in the development of leukemia, splenectomy was performed on weanling ICRC males which are susceptible to spontaneous leukemia .
The observation of localized lymphocytec neoplasm in
15% (3/20) of the splenectcmized mice and a solitary generalized lymphocytec neoplasm in a control male suggest that splenectcany was unable to control the leukemia development .
It seems that the spleen, being one of the important
hemopoietic organs carrying out the twofold func tions of the production of lymphocytes in white pulp and. the filtration of blood in red pulp, if removed, exerts a stress on the lympho-hemopoietic organs which have to carry the function(s) of the missing spleen .
Kalpaktsoglou et al . (4) found an increase
in the number of circulating lymphocytes in prepuberally splenectamized C3H(Bi) mice, however, no case of leukemia was observed in these mice (personal communication) . The value of splenectomy in chronic myeloid leukemia has been questioned as the patients developed progressive anemia, pancytopenia and myeofibrotic bone marrow (5) .
In chronic lymphocytec leukemia splenectcm~y is often con
sidered along with steroid therapy, however, the routine use of this procedure is disfavored because of the fatal condition of the disease (6) .
The present
data further confirmed that splenectamy alone failed to help the remission of the disease induced by transplantation of leukemic spleen .
The failure of the
"tumor takes" in splenectamized males, however, is difficult to explain.
Vol . 10, No. 8
Splenectomy and Leukemia
479
Acknowledents The technical assistance of Mr . B. A . Dhopte and Mr . R . S . Dolas is gratefully acknowledged ; and it is a pleasure to express our appreciation to Mr . R. Y. Nerurkar . References
4, 377 (1944) .
1.
D. P. McEndy, M. C . Boon and J . Furth, Cancer Res.
2.
H. D. Kaplan, J. Natl Cancer Inst . 11,
3.
T. M. Dunn, J. Natl Cancer Inst .
4.
P . K. Kalpaktsoglou, E. J. Yunis and R . J. Good, Anat . Rec .
5.
A. Leranto, Duodecim
6.
W. Dameshek and T . Gunz, Leukemia (Gruse and Stratten, eds), P
114 , 1281 (1954) .
(1968) .
392,
83 (1950) . 160, 781
81, 482 (1965) .
New York and London
(1960) .
356
and