The Experts below are selected from a list of 165 Experts worldwide ranked by ideXlab platform
Akira Ito - One of the best experts on this subject based on the ideXlab platform.
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Ultrasonographic and serologic studies of experimental cysticercosis in rats infected with Taenia Taeniaeformis
Parasite immunology, 1998Co-Authors: Akira Ito, Kazuhito Asano, Yoshimi Sakakibara, Mitsuyoshi Takiguchi, Jun Yasuda, Akira HashimotoAbstract:Rats experimentally infected with Taenia Taeniaeformis were followed-up until 14 weeks post inoculation with eggs (PIE) by hepatic ultrasonographic (US) image and serum antibody response analyses. Parasitic cysts could be imaged as small (2 mm in diameter) anechoic areas with or without a parenthesis-like echogenic small line from two weeks PIE. Immunoblot analysis using antigens from oncospheres (TtO), 30-day-old (TtM-30) and 300-day-old metacestodes (TtM-300) revealed that: (1) these three different developmental stages showed their own unique patterns suggesting the presence of stage-specific antigens; (2) faint IgM antibody responses to some components of TtO and TtM-30 or TtM-300 could be detected from one and two weeks PIE, respectively, and (3) IgG responses to some major components of both TtO and TtM-300, and TtM-30 were easily detected from four and five weeks PIE onwards, respectively. Both TtO and TtM (especially TtM-300) appeared to be highly useful for detection of antibody responses in experimentally infected rats. Due to the easiness in preparation of antigens, fully developed metacestodes may be the best candidate antigens for serodiagnosis. These results strongly suggest that both US image and antibody analyses using antigens from fully developed metacestodes are useful for detection of the early stage of cysticercosis in laboratory animal model.
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Cystic metacestodes of a rat-adapted Taenia Taeniaeformis established in the peritoneal cavity of scid and nude mice
International journal for parasitology, 1997Co-Authors: Akira Ito, Yukita SatoAbstract:Abstract In vitro-hatched (but not activated) oncospheres of a rat-adapted strain of Taenia Taeniaeformis intraperitoneally inoculated into severe combined immunodeficiency (scid), congenitally athymic (nude) and immunocompetent (normal) female BALB c mice developed into cystic metacestodes in the peritoneal cavity (but not in the liver) of scid and nude mice exclusively. This suggests that cystic metacestodes of this parasite, usually harboured in the liver only, can establish in scid and nude mice provided that the oncospheres are inoculated into the peritoneal cavity. Immunodeficient mice, especially scid mice, may be a good experimental animal model for the intermediate host of any taeniid species, of human, domestic- or wild-animal origin.
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Intraspecific variation of isoenzymes in Taenia Taeniaeformis
International journal for parasitology, 1995Co-Authors: Munehiro Okamoto, Akira Ito, Yuzaburo Oku, Masao Kamiya, Tsutomu Kurosawa, T. AgatsumaAbstract:Abstract The technique of isoenzyme electrophoresis was applied to Japanese wild populations of Taenia Taeniaeformis (isolated from Norway rats) and three laboratory reared isolates (KRN isolated from a Malaysian Norway rat, BMM from a Belgian house mouse and ACR from a Japanese gray red-backed vole). The average heterozygosities of Japanese wild populations were fairly small and total genetic variability was 0.0499. The genetic make-up of T.Taeniaeformis in Norway rats was rather uniform in the whole of Japan. In KRN isolate, each of all 10 loci examined possessed the allele which was predominant in Japanese wild populations. Similarly, each of 9 loci in BMM isolate possessed the same alleles, but one of 2 alleles at HK locus was different from that in the others.T. Taeniaeformis parasitizing house mice and rats were considered to be genetically closely related to each other. In ACR isolate, 7 out of 10 loci possessed different alleles from those in the other populations. It was considered that ACR isolate was genetically distant and its phylogenetic origin in Japan should be different from worms parasitizing Norway rats.
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Protective antibodies against Taenia Taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres.
Parasite immunology, 1994Co-Authors: Akira Ito, Kazuhito Asano, Ken-ichi OkamotoAbstract:Antibody responses against Taenia Taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres were analysed by passive transfer of serum and Western blotting. When recipient rats were injected with 1 ml serum from donors infected with eggs (infected serum), they all showed complete resistance to oral egg challenge, whereas those injected with 1 ml serum from donors injected with either oncospheres or recombinant antigens (vaccinated serum) showed no resistance. IgG and IgG subclass responses detected by Western blotting revealed that antibody responses to oncosphere antigens in infected serum thoroughly differed from those in vaccinated serum. It is suggested that IgG2 alpha responses in infected serum should be used for screening of epitopes for candidate vaccine.
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In vitro hatching of oncospheres of Taenia Taeniaeformis using eggs isolated from fresh, frozen, formalin-fixed and ethanol-fixed segments
Journal of helminthology, 1994Co-Authors: T. Negita, Akira ItoAbstract:In order to establish a simple means of handling eggs of taeniid cestodes under non-biohazardous conditions, gravid segments of Taenia Taeniaeformis were fixed in ethanol or formalin or were frozen. In vitro hatching of oncospheres was carried out by the 0.5% sodium hypochlorite method using eggs isolated from the nonviable and viable segments. No oncospheres hatched from formalized eggs, whereas almost all oncospheres hatched from all other eggs but the number of oncospheres recovered was highly variable. Oncospheres hatched from eggs isolated from frozen segments were highly fragile. The highest figures for in vitro hatching of oncospheres were recorded when eggs isolated either from segments fixed in 70% ethanol or from viable segments were used.
Masao Kamiya - One of the best experts on this subject based on the ideXlab platform.
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Taenia Taeniaeformis : Colonic hyperplasia in heavily infected rats
Experimental parasitology, 2008Co-Authors: Jose Trinipil Lagapa, Yuzaburo Oku, Masao KamiyaAbstract:Only one study previously mentioned the involvement of colon during Taenia Taeniaeformis larvae infection in rats with inconsistent occurrence of lesions. Present study aimed to determine the consistency of histopathologic changes in colonic epithelia, and the proliferation of mucosal cells through BrdU and PCNA immunohistochemistry. Results demonstrated that crypt hyperplasia of the colon was found in all infected rats, although variable in degree even in a single tissue section. Cystic cavities were frequently seen in severely hyperplastic mucosa. Proliferative zone lengths were significantly increased and PCNA positive cells were observed throughout the colonic crypt lengths at 9 but not at 6 weeks post infection. Cell proliferation involving the major types of cells in the epithelial colon was also increased in infected rats at 9 weeks post infection, with labeling indices significantly greater than the control rats throughout the BrdU time course labeling. Findings suggested that massive increases in epithelial cells and depth of colonic crypts were due to a remarkable increase in cell proliferation. The study concluded that enteropathy in the colon during T. Taeniaeformis infection could be consistently observed in heavily infected rats.
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Taenia Taeniaeformis: fate and proliferation of mucosal cells during gastric hyperplasia in larvae infected rats.
Experimental parasitology, 2008Co-Authors: Jose Trinipil Lagapa, Yuzaburo Oku, Nariaki Nonaka, Masao KamiyaAbstract:Fate and proliferation of gastric mucosal cells during hyperplasia of Taenia Taeniaeformis eggs inoculated Wistar rats were investigated using PCNA immunohistochemistry, BrdU labeling and other histopathologic staining techniques. Results revealed marked cell proliferation in gastric corpus and antral mucosa of infected rats as evidenced by increased lengths of proliferative zones and indices of BrdU labeling. The gastropathy in corpus was characterized by massive accumulation of precursors, neck and intermediate cells following significant decreases in numbers of parietal and zymogenic cells. Gastropathy in antrum was described with significant increases in precursors and mucous cells. Our results suggested that T. Taeniaeformis-induced gastric hyperplasia was initiated by depletion of parietal cells presumably due to the cestode's ES products. As a result, there was inhibition of zymogenic cell differentiation due to the disruption of normal development pathways of gastric mucosal lineages. These sequences of events were considered to cause the increase in cell proliferation and accumulation of intermediate cells resulting to the hyperplastic lesions.
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Retarded gastric acid secretion in rats infected with larval Taenia Taeniaeformis.
Parasitology research, 2002Co-Authors: Yuzaburo Oku, Jose Alexander Abella, Hong-kean Ooi, T. Yamanouchi, K. Matsuda, R. Ohtsubo, Y. Goto, Masao KamiyaAbstract:The influence of hepatic larval Taenia Taeniaeformis infection on gastric acid secretory activity and gastric mucosal integrity was investigated. After 12 weeks of infection with 2,000 T. Taeniaeformis eggs, the gastric pH values of control and infected rats were 4.1±0.6 (mean ± SD) and 8.4±0.2, respectively. There was no difference in the basal acid secretion between control (1.7±0.7 µEq.H+/15 min) and infected (1.9±0.3) rats. However, infected rats failed to respond to histamine stimulation, the maximum acid output level being 2.8±0.4 in the infected rats, compared to 12.9±3.3 in control rats. Larval T. Taeniaeformis infection resulted in the suppression of gastric acid secretion leading to hypergastrinemia.
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Taenia Taeniaeformis larval product induces gastric mucosal hyperplasia in scid mice
Japanese Journal of Veterinary Research, 2002Co-Authors: Jose Trinipil G Lagapa, Yuzaburo Oku, Nariaki Nonaka, Masao KamiyaAbstract:The effects of intraperitoneal implantation of Taenia Taeniaeformis lar vae and inoculation of in vitro larval products on gastric mucosa of SelD mice were investigated in this study. Mice surgically implanted with T. Taeniae formis larvae developed slight and moderate gastric hyperplasia. When in vi tro cultured T. Taeniaeformis larval excretory-secretory (TtLES) products con taining 1 mg of protein were injected daily into mice, they caused gastropathy after 5-7 days. Mice injected daily with O. 5mg ofTtLES products also showed slight gastric hyperplasia after day 14 and 28. The gastropathy was character ized by reduction of both parietal and zymogenic cell number and increased number of alcian blue-periodic acid Schiff (AB-PAS) -positive cells and by two -fold extension of proliferative zone of gastric units. Larval implantation dem onstrated a more potent effect in inducing gastropathy than did in vitro larval culture products. Significant decrease in number of parietal cells with con comitant increase of proliferative zone and AB-PAS-positive cell number indi cated their important roles in inducing the hyperplastic lesion. Similarities with other gastropathies indicated that there is a common fundamental regu latory mechanism involved, and that the host response may not be specific to parasites. Present study validated the induction of gastric mucosal hyperpla sia by larval ES products of T. Taeniaeformis. This proved the hypothesis of previous studies suggesting the role of larvae-derived products in inducing gastric mucosal hyperplasia in T. Taeniaeformis-infected rats.
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Gastric hyperplasia and parietal cell loss in Taenia Taeniaeformis inoculated immunodeficient mice
Parasitology international, 2002Co-Authors: Jose Trinipil G Lagapa, Yuzaburo Oku, Kenjiro Konno, Nariaki Nonaka, Mamoru Ito, Masao KamiyaAbstract:Immunodeficient mice were studied to determine their suitability as models in investigating the role of Taenia Taeniaeformis larval products in the development of gastric hyperplasia. Recombinant active gene 2 (RAG2)-deficient and severe combined immune-deficient (SCID) mice were studied as candidate animal models. RAG2-deficient mice inoculated orally with T. Taeniaeformis eggs developed gastric hyperplasia with alcian blue-periodic acid-Schiff-positive cell proliferation similar to those of rats. SCID mice inoculated with different doses and routes of T. Taeniaeformis in vitro-hatched oncospheres and those orally inoculated with eggs resulted also in different degrees of gastric hyperplasia. Influence of inoculation forms of parasite, doses and routes of inoculation on initiation of hyperplastic gastropathy was suggested to be dependent on number and size of developed larvae. Both RAG2-deficient and SCID mice with hyperplastic mucosa were observed with significant loss of parietal cells. Apparent decrease in parietal cell number was observed in SCID mice at 2 weeks after intraperitoneal inoculation with oncospheres before hyperplastic lesions developed. Earliest occurrence of gastric hyperplasia in SCID mice was observed at 3 weeks after oral inoculation of in vitro-hatched oncospheres, sooner than orally inoculated rats. The results suggested that these immunodeficient mice could be used as animal models to study factors involved in T. Taeniaeformis-induced gastric mucous cell hyperplasia.
Ken-ichi Okamoto - One of the best experts on this subject based on the ideXlab platform.
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Protective antibodies against Taenia Taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres.
Parasite immunology, 1994Co-Authors: Akira Ito, Kazuhito Asano, Ken-ichi OkamotoAbstract:Antibody responses against Taenia Taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres were analysed by passive transfer of serum and Western blotting. When recipient rats were injected with 1 ml serum from donors infected with eggs (infected serum), they all showed complete resistance to oral egg challenge, whereas those injected with 1 ml serum from donors injected with either oncospheres or recombinant antigens (vaccinated serum) showed no resistance. IgG and IgG subclass responses detected by Western blotting revealed that antibody responses to oncosphere antigens in infected serum thoroughly differed from those in vaccinated serum. It is suggested that IgG2 alpha responses in infected serum should be used for screening of epitopes for candidate vaccine.
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The role of OX22− helper T cells in protective immunity to reinfection with Taenia Taeniaeformis in rats
Parasite immunology, 1993Co-Authors: Kazuhito Asano, Akira Ito, Ken-ichi OkamotoAbstract:Summary Spleen cells (SpC) and mesenteric lymph node cells (MLNC) from F344 donor rats actively immunized by oral inoculation with Taenia Taeniaeformis eggs were syngeneically transferred into previously uninfected recipient rats by intravenous injection. Recipient rats were challenged with eggs after cell transfer. The degree of immunity was assessed by counting the number of growing metacestodes (MC) in the liver and compared with that in controls. Transfer of 2 × 108 SpC, obtained from donors immunized for ten or more (but not for three or five) days before cell transfer inhibited the establishment of most of MC. There were approximately 86–88% reductions in MC recoveries. SpC (2 × 108) obtained from donors immunized for ten days inhibited the establishment of most of MC in recipient rats when transferred nought, two, or 24 h (but not 48 h) before egg challenge. Functional cells in the immune SpC were helper T cells W3/25+, OX8− and OX22−. However, immune MLNC obtained from donors immunized for three to ten days before cell transfer had no effect on transferring immunity.
Yuzaburo Oku - One of the best experts on this subject based on the ideXlab platform.
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Taenia Taeniaeformis : Colonic hyperplasia in heavily infected rats
Experimental parasitology, 2008Co-Authors: Jose Trinipil Lagapa, Yuzaburo Oku, Masao KamiyaAbstract:Only one study previously mentioned the involvement of colon during Taenia Taeniaeformis larvae infection in rats with inconsistent occurrence of lesions. Present study aimed to determine the consistency of histopathologic changes in colonic epithelia, and the proliferation of mucosal cells through BrdU and PCNA immunohistochemistry. Results demonstrated that crypt hyperplasia of the colon was found in all infected rats, although variable in degree even in a single tissue section. Cystic cavities were frequently seen in severely hyperplastic mucosa. Proliferative zone lengths were significantly increased and PCNA positive cells were observed throughout the colonic crypt lengths at 9 but not at 6 weeks post infection. Cell proliferation involving the major types of cells in the epithelial colon was also increased in infected rats at 9 weeks post infection, with labeling indices significantly greater than the control rats throughout the BrdU time course labeling. Findings suggested that massive increases in epithelial cells and depth of colonic crypts were due to a remarkable increase in cell proliferation. The study concluded that enteropathy in the colon during T. Taeniaeformis infection could be consistently observed in heavily infected rats.
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Taenia Taeniaeformis: fate and proliferation of mucosal cells during gastric hyperplasia in larvae infected rats.
Experimental parasitology, 2008Co-Authors: Jose Trinipil Lagapa, Yuzaburo Oku, Nariaki Nonaka, Masao KamiyaAbstract:Fate and proliferation of gastric mucosal cells during hyperplasia of Taenia Taeniaeformis eggs inoculated Wistar rats were investigated using PCNA immunohistochemistry, BrdU labeling and other histopathologic staining techniques. Results revealed marked cell proliferation in gastric corpus and antral mucosa of infected rats as evidenced by increased lengths of proliferative zones and indices of BrdU labeling. The gastropathy in corpus was characterized by massive accumulation of precursors, neck and intermediate cells following significant decreases in numbers of parietal and zymogenic cells. Gastropathy in antrum was described with significant increases in precursors and mucous cells. Our results suggested that T. Taeniaeformis-induced gastric hyperplasia was initiated by depletion of parietal cells presumably due to the cestode's ES products. As a result, there was inhibition of zymogenic cell differentiation due to the disruption of normal development pathways of gastric mucosal lineages. These sequences of events were considered to cause the increase in cell proliferation and accumulation of intermediate cells resulting to the hyperplastic lesions.
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Retarded gastric acid secretion in rats infected with larval Taenia Taeniaeformis.
Parasitology research, 2002Co-Authors: Yuzaburo Oku, Jose Alexander Abella, Hong-kean Ooi, T. Yamanouchi, K. Matsuda, R. Ohtsubo, Y. Goto, Masao KamiyaAbstract:The influence of hepatic larval Taenia Taeniaeformis infection on gastric acid secretory activity and gastric mucosal integrity was investigated. After 12 weeks of infection with 2,000 T. Taeniaeformis eggs, the gastric pH values of control and infected rats were 4.1±0.6 (mean ± SD) and 8.4±0.2, respectively. There was no difference in the basal acid secretion between control (1.7±0.7 µEq.H+/15 min) and infected (1.9±0.3) rats. However, infected rats failed to respond to histamine stimulation, the maximum acid output level being 2.8±0.4 in the infected rats, compared to 12.9±3.3 in control rats. Larval T. Taeniaeformis infection resulted in the suppression of gastric acid secretion leading to hypergastrinemia.
-
Taenia Taeniaeformis larval product induces gastric mucosal hyperplasia in scid mice
Japanese Journal of Veterinary Research, 2002Co-Authors: Jose Trinipil G Lagapa, Yuzaburo Oku, Nariaki Nonaka, Masao KamiyaAbstract:The effects of intraperitoneal implantation of Taenia Taeniaeformis lar vae and inoculation of in vitro larval products on gastric mucosa of SelD mice were investigated in this study. Mice surgically implanted with T. Taeniae formis larvae developed slight and moderate gastric hyperplasia. When in vi tro cultured T. Taeniaeformis larval excretory-secretory (TtLES) products con taining 1 mg of protein were injected daily into mice, they caused gastropathy after 5-7 days. Mice injected daily with O. 5mg ofTtLES products also showed slight gastric hyperplasia after day 14 and 28. The gastropathy was character ized by reduction of both parietal and zymogenic cell number and increased number of alcian blue-periodic acid Schiff (AB-PAS) -positive cells and by two -fold extension of proliferative zone of gastric units. Larval implantation dem onstrated a more potent effect in inducing gastropathy than did in vitro larval culture products. Significant decrease in number of parietal cells with con comitant increase of proliferative zone and AB-PAS-positive cell number indi cated their important roles in inducing the hyperplastic lesion. Similarities with other gastropathies indicated that there is a common fundamental regu latory mechanism involved, and that the host response may not be specific to parasites. Present study validated the induction of gastric mucosal hyperpla sia by larval ES products of T. Taeniaeformis. This proved the hypothesis of previous studies suggesting the role of larvae-derived products in inducing gastric mucosal hyperplasia in T. Taeniaeformis-infected rats.
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Gastric hyperplasia and parietal cell loss in Taenia Taeniaeformis inoculated immunodeficient mice
Parasitology international, 2002Co-Authors: Jose Trinipil G Lagapa, Yuzaburo Oku, Kenjiro Konno, Nariaki Nonaka, Mamoru Ito, Masao KamiyaAbstract:Immunodeficient mice were studied to determine their suitability as models in investigating the role of Taenia Taeniaeformis larval products in the development of gastric hyperplasia. Recombinant active gene 2 (RAG2)-deficient and severe combined immune-deficient (SCID) mice were studied as candidate animal models. RAG2-deficient mice inoculated orally with T. Taeniaeformis eggs developed gastric hyperplasia with alcian blue-periodic acid-Schiff-positive cell proliferation similar to those of rats. SCID mice inoculated with different doses and routes of T. Taeniaeformis in vitro-hatched oncospheres and those orally inoculated with eggs resulted also in different degrees of gastric hyperplasia. Influence of inoculation forms of parasite, doses and routes of inoculation on initiation of hyperplastic gastropathy was suggested to be dependent on number and size of developed larvae. Both RAG2-deficient and SCID mice with hyperplastic mucosa were observed with significant loss of parietal cells. Apparent decrease in parietal cell number was observed in SCID mice at 2 weeks after intraperitoneal inoculation with oncospheres before hyperplastic lesions developed. Earliest occurrence of gastric hyperplasia in SCID mice was observed at 3 weeks after oral inoculation of in vitro-hatched oncospheres, sooner than orally inoculated rats. The results suggested that these immunodeficient mice could be used as animal models to study factors involved in T. Taeniaeformis-induced gastric mucous cell hyperplasia.
Kazuhito Asano - One of the best experts on this subject based on the ideXlab platform.
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Ultrasonographic and serologic studies of experimental cysticercosis in rats infected with Taenia Taeniaeformis
Parasite immunology, 1998Co-Authors: Akira Ito, Kazuhito Asano, Yoshimi Sakakibara, Mitsuyoshi Takiguchi, Jun Yasuda, Akira HashimotoAbstract:Rats experimentally infected with Taenia Taeniaeformis were followed-up until 14 weeks post inoculation with eggs (PIE) by hepatic ultrasonographic (US) image and serum antibody response analyses. Parasitic cysts could be imaged as small (2 mm in diameter) anechoic areas with or without a parenthesis-like echogenic small line from two weeks PIE. Immunoblot analysis using antigens from oncospheres (TtO), 30-day-old (TtM-30) and 300-day-old metacestodes (TtM-300) revealed that: (1) these three different developmental stages showed their own unique patterns suggesting the presence of stage-specific antigens; (2) faint IgM antibody responses to some components of TtO and TtM-30 or TtM-300 could be detected from one and two weeks PIE, respectively, and (3) IgG responses to some major components of both TtO and TtM-300, and TtM-30 were easily detected from four and five weeks PIE onwards, respectively. Both TtO and TtM (especially TtM-300) appeared to be highly useful for detection of antibody responses in experimentally infected rats. Due to the easiness in preparation of antigens, fully developed metacestodes may be the best candidate antigens for serodiagnosis. These results strongly suggest that both US image and antibody analyses using antigens from fully developed metacestodes are useful for detection of the early stage of cysticercosis in laboratory animal model.
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Protective antibodies against Taenia Taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres.
Parasite immunology, 1994Co-Authors: Akira Ito, Kazuhito Asano, Ken-ichi OkamotoAbstract:Antibody responses against Taenia Taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres were analysed by passive transfer of serum and Western blotting. When recipient rats were injected with 1 ml serum from donors infected with eggs (infected serum), they all showed complete resistance to oral egg challenge, whereas those injected with 1 ml serum from donors injected with either oncospheres or recombinant antigens (vaccinated serum) showed no resistance. IgG and IgG subclass responses detected by Western blotting revealed that antibody responses to oncosphere antigens in infected serum thoroughly differed from those in vaccinated serum. It is suggested that IgG2 alpha responses in infected serum should be used for screening of epitopes for candidate vaccine.
-
The role of OX22− helper T cells in protective immunity to reinfection with Taenia Taeniaeformis in rats
Parasite immunology, 1993Co-Authors: Kazuhito Asano, Akira Ito, Ken-ichi OkamotoAbstract:Summary Spleen cells (SpC) and mesenteric lymph node cells (MLNC) from F344 donor rats actively immunized by oral inoculation with Taenia Taeniaeformis eggs were syngeneically transferred into previously uninfected recipient rats by intravenous injection. Recipient rats were challenged with eggs after cell transfer. The degree of immunity was assessed by counting the number of growing metacestodes (MC) in the liver and compared with that in controls. Transfer of 2 × 108 SpC, obtained from donors immunized for ten or more (but not for three or five) days before cell transfer inhibited the establishment of most of MC. There were approximately 86–88% reductions in MC recoveries. SpC (2 × 108) obtained from donors immunized for ten days inhibited the establishment of most of MC in recipient rats when transferred nought, two, or 24 h (but not 48 h) before egg challenge. Functional cells in the immune SpC were helper T cells W3/25+, OX8− and OX22−. However, immune MLNC obtained from donors immunized for three to ten days before cell transfer had no effect on transferring immunity.