Int. J . Cancer: 23, 728-734 (1979)
NATURAL CELL-MEDIATED CYTOTOXICITY IN HAMSTERS Surjit K. DATTA, Michael T. GALLAGHER and John J . TRENTIN Division of Experimental Biology, Baylor College of Medicine, Houston, Texas 77030, USA
Lymphoid cells from normal inbred LSH and random-bred Syrian golden hamsters were evaluated for natural cytotoxic activity against cultured simian adenovirus 7 (SA7)-induced lymphoma of the L S H hamster employing the 5"Crrelease cytotoxicity assay. Natural cytotoxic reactivity was found in both inbred and random-bred hamsters. The level of activity was much higher in random-bred (38.2% lysis) than in inbred (14.9%) hamsters. The percentage lysis of SA7 target cells was proportional t o the effector:target cell (E:T) ratio. Natural cytotoxic reactivity was high i n both spleen and bone marrow intermediate in mesenteric lymph node, and low or non-existent i n thymus. Natural cytotoxic responses were present In 4- t o 7-day-old, adult and aged (1- t o 1%-year-old) hamsters. Exposure of hamsters t o 1,100 R of wholebody irradiation had l i t t l e o r no effect on natural cytotoxic reactivity, indicating the radio-resistant nature of the reactivity in hamsters, as i n mice. Treatment of hamsters with a single dose of either 500 mg cytoxan/kg intraperitoneally (IP), o r 5 mg carrageenan I P markedly suppressed their natural cytotoxic responses, as i n mice. Growth of transplanted SA7 tumor in inbred hamsters o r of D, lymphoma i n random-bred hamsters strongly inhibited the natural spleen-cell-mediated lysis of SA7 lymphoma cells. Thus, while hamster natural cytotoxic activity shared most of the properties of mouse N K activity, it differed in (1) appearing earlier in life (2) increasing progressively into older age (1 years) and (3) being as high i n bone marrow as in spleen, or higher.
Recently, natural cell-mediated immunity mediated by natural killer (NK) cells has been described in the mouse (Herberman et al., 19750; Kiessling et al., 197%; Sendo et al., 1975; Zarling et al., 1975), rat (Nunn et al., 1976; Shellam and Hogg, 1977) and man (Oldham et al., 1975; Takasugi et al., 1973; Rosenberg et al., 1974; West et al., 1977) against target cells of a variety of tumors. NK reactivity has been extensively studied in mice, against syngeneic and allogeneic tumor target cells (Herberman et al., 1975a; Kiessling et al., 19751; Herberman and Holden, 1978). Mice can be divided into high- (CBA, C3H, C57, etc.) and low(A, AKR, etc.) responder strains. Athymic nude and Lasat (cross between athymic and asplenic) mice have higher NK cell activity than conventional mice. The N K cells are distributed in various lymphoid compartments, such as spleen, lymph node, peripheral blood and bone marrow, and may be elicited in the peritoneal cavity. Spleen has the highest NK cell reactivity, bone marrow has little and thymus cells are inactive. N K reactivity appears around 3 weeks of post-natal age, reaches a maximum level in 5-8 weeks and thereafter declines. However, natural cytotoxic (Nc) cells against chemically-induced solid tumors (sarcoma, etc.)
reported by Stutman et al. (1978) differ in both age and organ distribution. Nc cells appear at birth and do not decline with age. Spleen and bone marrow have high levels of Nc cell activity, thymus intermediate levels, and lymph node and peritoneal cells low levels. The nature of the effector cells mediating natural cytotoxicity in rodents has been mainly studied by Kiessling a n d by Herberman with their associates (Kiessling et al., 19756; Herberman et al., 1975b; Nunn et al., 1976). Their studies suggest that ( I ) although N K cells are small lymphocytes they cannot be classified as mature T or B cells or as monocyte-macrophage cells, using standard ccll characterization procedures; (2) N K cells apparently do not take part in antibody-dependent cdlular cytotoxicity; (3) the presence of NK activity is controlled in part by genes in the H-2 complex in the mouse. A recent study by Herberman et al. (1977) indicates that mouse NK cells may be pre-T cells having a low density of Fc receptor. On the other hand, there is general agreement that human NK cells bear Fc receptors but do not belong to the classical T or B or monocyte-macrophage categories (Pross and Jondal, 1975; Santoli et al., 1976; Kiuchi and Takasugi, 1976; West et al., 1977). However, under optimal rosetting conditions, they can be recovered in the E-rosetting fractions (Kay et al., 1977). Recently the phenomenon of genetic resistance (GR) to bone-marrow transplantation (Trentin et al., 1973) was compared with spleen NK-cell-mediated lysis of YAC-1 lymphoma target cells by us and others (Trentin et al., 1977; Kiessling et al., 1977). From the results, there appears to be identity between the effector mechanisms of GR and NK-cellmediated lysis. Both G R in vivo and N K cell lysis in vitro showed common characteristics. They both start functioning around 3 weeks of age and are radio-resistant and susceptible to cyclophosphamide, anti-macrophage agents carrageenan and silica, anti-bone-marrow and anti-thymocyte sera and strontium-89 treatment. The biological significance of natural cytotoxicity, although potentially very important, is not fully established. It is considered to be a new mechanism of cell-mediated cancer immunity, different from classical T, B and monocyte-macrophage immunity. It is therefore desirable to investigate the presence of NK cell activity in different species to establish whether it is a general phenomenon having a possible role in natural surveillance against the development Received: October 25, 1978 and in revised form February 20,1979.
729
NATURAL CYTOTOXIC CELLS IN HAMSTERS
TABLE I NATURAL CYTOTOXIC CELL LYSIS OF SA7 LYMPHOMA CELLS BY SPLEEN CELLS FROM 3-MONTH-OLD LSH INBRED OR RANDOM-BRED SYRIAN HAMSTERS
Experiment No.
No. of animals
Effector to SA7 target cell ratio
loo:] 1oo:l 100:l 1OO:l 1OO:l 1OO:l 1OO:l 1OO:l
Mean % lysis (range) (16-18 h incubation) Inbred
Random-bred
16.9 18.2 11.2 9.7 11.6 19.6 21.7 10.2
21.6 31.2 47.4 41.9 15.6 39.3 74.4 34.3
14.9 (9.7-21.7) p = c0.05
38.2 (15.6-74.4) p =
NATURAL CELL-MEDIATED CYTOTOXICITY IN HAMSTERS Surjit K. DATTA, Michael T. GALLAGHER and John J . TRENTIN Division of Experimental Biology, Baylor College of Medicine, Houston, Texas 77030, USA
Lymphoid cells from normal inbred LSH and random-bred Syrian golden hamsters were evaluated for natural cytotoxic activity against cultured simian adenovirus 7 (SA7)-induced lymphoma of the L S H hamster employing the 5"Crrelease cytotoxicity assay. Natural cytotoxic reactivity was found in both inbred and random-bred hamsters. The level of activity was much higher in random-bred (38.2% lysis) than in inbred (14.9%) hamsters. The percentage lysis of SA7 target cells was proportional t o the effector:target cell (E:T) ratio. Natural cytotoxic reactivity was high i n both spleen and bone marrow intermediate in mesenteric lymph node, and low or non-existent i n thymus. Natural cytotoxic responses were present In 4- t o 7-day-old, adult and aged (1- t o 1%-year-old) hamsters. Exposure of hamsters t o 1,100 R of wholebody irradiation had l i t t l e o r no effect on natural cytotoxic reactivity, indicating the radio-resistant nature of the reactivity in hamsters, as i n mice. Treatment of hamsters with a single dose of either 500 mg cytoxan/kg intraperitoneally (IP), o r 5 mg carrageenan I P markedly suppressed their natural cytotoxic responses, as i n mice. Growth of transplanted SA7 tumor in inbred hamsters o r of D, lymphoma i n random-bred hamsters strongly inhibited the natural spleen-cell-mediated lysis of SA7 lymphoma cells. Thus, while hamster natural cytotoxic activity shared most of the properties of mouse N K activity, it differed in (1) appearing earlier in life (2) increasing progressively into older age (1 years) and (3) being as high i n bone marrow as in spleen, or higher.
Recently, natural cell-mediated immunity mediated by natural killer (NK) cells has been described in the mouse (Herberman et al., 19750; Kiessling et al., 197%; Sendo et al., 1975; Zarling et al., 1975), rat (Nunn et al., 1976; Shellam and Hogg, 1977) and man (Oldham et al., 1975; Takasugi et al., 1973; Rosenberg et al., 1974; West et al., 1977) against target cells of a variety of tumors. NK reactivity has been extensively studied in mice, against syngeneic and allogeneic tumor target cells (Herberman et al., 1975a; Kiessling et al., 19751; Herberman and Holden, 1978). Mice can be divided into high- (CBA, C3H, C57, etc.) and low(A, AKR, etc.) responder strains. Athymic nude and Lasat (cross between athymic and asplenic) mice have higher NK cell activity than conventional mice. The N K cells are distributed in various lymphoid compartments, such as spleen, lymph node, peripheral blood and bone marrow, and may be elicited in the peritoneal cavity. Spleen has the highest NK cell reactivity, bone marrow has little and thymus cells are inactive. N K reactivity appears around 3 weeks of post-natal age, reaches a maximum level in 5-8 weeks and thereafter declines. However, natural cytotoxic (Nc) cells against chemically-induced solid tumors (sarcoma, etc.)
reported by Stutman et al. (1978) differ in both age and organ distribution. Nc cells appear at birth and do not decline with age. Spleen and bone marrow have high levels of Nc cell activity, thymus intermediate levels, and lymph node and peritoneal cells low levels. The nature of the effector cells mediating natural cytotoxicity in rodents has been mainly studied by Kiessling a n d by Herberman with their associates (Kiessling et al., 19756; Herberman et al., 1975b; Nunn et al., 1976). Their studies suggest that ( I ) although N K cells are small lymphocytes they cannot be classified as mature T or B cells or as monocyte-macrophage cells, using standard ccll characterization procedures; (2) N K cells apparently do not take part in antibody-dependent cdlular cytotoxicity; (3) the presence of NK activity is controlled in part by genes in the H-2 complex in the mouse. A recent study by Herberman et al. (1977) indicates that mouse NK cells may be pre-T cells having a low density of Fc receptor. On the other hand, there is general agreement that human NK cells bear Fc receptors but do not belong to the classical T or B or monocyte-macrophage categories (Pross and Jondal, 1975; Santoli et al., 1976; Kiuchi and Takasugi, 1976; West et al., 1977). However, under optimal rosetting conditions, they can be recovered in the E-rosetting fractions (Kay et al., 1977). Recently the phenomenon of genetic resistance (GR) to bone-marrow transplantation (Trentin et al., 1973) was compared with spleen NK-cell-mediated lysis of YAC-1 lymphoma target cells by us and others (Trentin et al., 1977; Kiessling et al., 1977). From the results, there appears to be identity between the effector mechanisms of GR and NK-cellmediated lysis. Both G R in vivo and N K cell lysis in vitro showed common characteristics. They both start functioning around 3 weeks of age and are radio-resistant and susceptible to cyclophosphamide, anti-macrophage agents carrageenan and silica, anti-bone-marrow and anti-thymocyte sera and strontium-89 treatment. The biological significance of natural cytotoxicity, although potentially very important, is not fully established. It is considered to be a new mechanism of cell-mediated cancer immunity, different from classical T, B and monocyte-macrophage immunity. It is therefore desirable to investigate the presence of NK cell activity in different species to establish whether it is a general phenomenon having a possible role in natural surveillance against the development Received: October 25, 1978 and in revised form February 20,1979.
729
NATURAL CYTOTOXIC CELLS IN HAMSTERS
TABLE I NATURAL CYTOTOXIC CELL LYSIS OF SA7 LYMPHOMA CELLS BY SPLEEN CELLS FROM 3-MONTH-OLD LSH INBRED OR RANDOM-BRED SYRIAN HAMSTERS
Experiment No.
No. of animals
Effector to SA7 target cell ratio
loo:] 1oo:l 100:l 1OO:l 1OO:l 1OO:l 1OO:l 1OO:l
Mean % lysis (range) (16-18 h incubation) Inbred
Random-bred
16.9 18.2 11.2 9.7 11.6 19.6 21.7 10.2
21.6 31.2 47.4 41.9 15.6 39.3 74.4 34.3
14.9 (9.7-21.7) p = c0.05
38.2 (15.6-74.4) p =
