Anticancer immunotherapy has undergone a long evolving journey for decades, and has been dramatically applied to mainstream treatments in oncology in recent 5 years. This progress represents an advanced milestone foll...Anticancer immunotherapy has undergone a long evolving journey for decades, and has been dramatically applied to mainstream treatments in oncology in recent 5 years. This progress represents an advanced milestone following cytotoxic medicine and targeted therapy. Cellular immunity plays a pivotal role in the immune responses of hosts to tumor antigens. Such immunity is notably suppressed during neoplastic progression due to immuno-editing processes. Cellular immunity can also be selectively reactivated to combat malignancies while exploiting the advantages of contemporary scientific breakthroughs in molecular immunology and genetic engineering. The rapid advancement of cellular immunity-based therapeutic approaches has achieved high efficacy in certain cancer patients. Consequently, the landscape of oncologic medicine and pharmaceutical innovation has transformed recently. In this regard, we present a comprehensive update on clinically established anti-cancer treatments with cell immunity augmentation as the major mechanism of action.展开更多
Objective： The aim of the study was to investigate whether dendritic cell （DC） precursors, recruited by injection of chemokine ligand 3 （CCL3）, induce enhanced anti-tumor immunity after granulocyte-macrophage col...Objective： The aim of the study was to investigate whether dendritic cell （DC） precursors, recruited by injection of chemokine ligand 3 （CCL3）, induce enhanced anti-tumor immunity after granulocyte-macrophage colony stimulating factor （GM-CSF） transfection in mice ex vivo. Methods： The 615 mice were injected with CCL3 via the tail vein. Freshly isolated B220–CD11c＋ cells were cultured with cytokines. For adenoviral （Ad）-mediated gene transduction, DCs were transferred AdGM-CSF gene at different ratios of multiplicity of infection （MOI） to determine the optimal gene transfection conditions, and detecting the expression of GM-CSF after transfection. The variation of GM-CSF gene-modified DCs were analyzed by morphological observation, phenotype analysis, and mixed lymphocyte reaction （MLR）. DCs were loaded with gastric cancer antigen obtained by frozen and thawed method. The stimulated DCs vaccination induced T lymphocytes, and the killing effect of T cells to gastric cancer cells was assayed by MTT. INF-γ production was determined with the INF-γ ELISA kit. Results： B220–CD11c＋ cells numbers increased after CCL3 injection. ELISA results showed that after GM-CSF gene modification, DC could produce high level of GM-CSF. When DCs were transferred AdGM-CSF gene at MOI equal to 1：100, GM-CSF level in culture supernatants reached saturation [（130.00 ± 12.61） pg/mL]. After GM-CSF gene-modification, DCs tended to more maturated through morphological observation and were phenotypically identical to typical DC and gained the capacity to stimulate allogeneic T cells. T lymphocytes stimulated with DC transduced with GM-CSF gene showed the specific killing effect on gastric carcinoma cells and produced high level of INF-γ [（1245.00 ± 13.75） pg/mL]. Conclusion： CCL3-recruited DCs modified by adenovirus-transducted GM-CSF could produce high level of GM-CSF, which tended to more maturated, and the capacity of activating allogeneic T lymphocytes proliferation was enhanced greatly. Moreover, they could stimulate specific cytotoxic T lymphocyte （CTL） to gastric cancer ex vivo.展开更多
AIM: To investigate the effect of bone marrow-derived monocytes transfected with RNA of CT-26 (a cell line of mouse colon carcinoma) on antitumor immunity. METHODS: Mouse bone marrow-derived monocytes were incubated w...AIM: To investigate the effect of bone marrow-derived monocytes transfected with RNA of CT-26 (a cell line of mouse colon carcinoma) on antitumor immunity. METHODS: Mouse bone marrow-derived monocytes were incubated with mouse granulocyte macrophage colony stimulating factor (mGM-CSF) in vitro, and the purity of monocytes was detected by flow cytometry. Total RNA of CT-26 was obtained by TRIzol's process, and monocytes were transfected by TransMessenger in vitro. The activity of cytotoxic T lymphocytes (CTL) in vivo was estimated by the modified lactate dehydrogenase (LDH) release assay. Changes of tumor size in mice and animal's survival time were observed in different groups. RESULTS: Monocytes from mouse bone marrow were successfully incubated, and the positive rate of CDllb was over 95%. Vaccination of the monocytes transfected with total RNA induced a high level of specific CTL activity in vivo, and made mice resistant to the subsequent challenge of parental tumor cells. In vivo effects induced by monocytes transfected with total RNA were stronger than those induced by monocytes pulsed with tumor cell lysates. CONCLUSION: Antigen presenting cells transfected with total RNA of CT-26 can present endogenous? tumor antigens, activate CTL, and effectively induce specific antitumor immunity.展开更多
AIM: To assess the significance of phosphatidylinositol 3-kinase (PI3K) in colorectal cancer (CRC) and toxicity of LY294002 in CRC cells with different metastatic abilities. METHODS: Sixty formalin-fixed and paraffin-...AIM: To assess the significance of phosphatidylinositol 3-kinase (PI3K) in colorectal cancer (CRC) and toxicity of LY294002 in CRC cells with different metastatic abilities. METHODS: Sixty formalin-fixed and paraffin-embedded CRC tumor specimens were investigated. Adjacent normal colonic mucosa specimens from 10 of these cases were selected as controls. PI3K protein was detected by immunohistochemistry and PIK3CA mutations were investigated by gene sequencing analysis. A flowcytometry-based apoptosis detection kit was used to determine PI3K inhibitor-induced apoptosis in CRC cell lines SW480 and SW620. Expression of phosphorylated protein kinase B in CRC cell lines was detected by Western blotting. RESULTS: There was a significant difference in the proportion of primary lesions (30%, 18/60) vs metastatic lesions (46.7%, 28/60) that were positive for PI3K (P < 0.05). Mutations were detected in exon 9 (13.3%) and exon 20 (8.3%). Out of 60 cases, seven mutations were identified: two hotspot mutations, C.1633G>A resulting in E545A, and C.3140A>G resulting in H1047R; two novel missense mutations C.1624G>A and C.3079G>A; and three synonymous mutations (C.1641G>A, C.1581C>T and C.3027T>A). Exposure of SW480 cells to PI3K inhibitor for 48 h resulted in a significant increase of apoptotic cells in a dose-dependent manner [3.2% apoptotic cells in 0 μmol/L, 4.3% in 5 μmol/L, 6.3% in 10 μmol/L (P < 0.05), and 6.7% in 20 μmol/L (P < 0.05)]. Moreover, PI3K inhibitor induced a similar significant increase of apoptotic cells in the SW620 cell line for 48 h [3.3% apoptotic cells in 0 μmol/L, 13.3% in 5 μmol/L (P < 0.01), 19.2% in 10 μmol/L (P < 0.01), and 21.3% in 20 μmol/L (P < 0.01)]. CONCLUSION: High PI3K expression is associated with CRC metastasis. PI3K inhibitor induced apoptosis in CRC cells and displayed strong cytotoxicity for highly metastatic cells. PI3K inhibition may be an effective treatment for CRC.展开更多
The effect of monoethylphosphate (MEP, commercial available or synthesized) together with IL-2 on the selective proliferation of human γ~δ T cells in Vitro from peripheral blood mononuclear cells (PBMC) of healthy d...The effect of monoethylphosphate (MEP, commercial available or synthesized) together with IL-2 on the selective proliferation of human γ~δ T cells in Vitro from peripheral blood mononuclear cells (PBMC) of healthy donors and of cancer patients was investigated. The γ~δ T cells were stimulated by MEP to proliferate in a dose-dependent manner. The effect of synthesized MEP was 10 times greater than that of commercial MEP. When the PBMCs of healthy donors were cultured for 25 d in the medium containing different concentrations of MEP, the total cell number increased about 1000-3000 fold; and the ratio of γ~δ T cells reached to 70-80%. The selective expansion of γ~δ T cells depended on the synergic action of MEP and IL-2. The bulk cultured γ~δ T cells exhibited obvious cytotoxic activities against allogenic tumor cell lines (SQ-5,K562 alld Daudi) and autologous tumor cells. The culture system described here not only offers a simple method for obtaining a large number of γ~δ T cells which may become a new effector in the adoptive immunotherapy, but also provides a useful model for the further studies of the structure and function of γ~δ T cells in vitro.展开更多
AIM: To explore dendritic cells (DCs) multiple functions in immune modulation. METHODS: We used bone-marrow derived dendritic cells from BALB/c mice pulsed with pseudo particles from the hepatitis C virus to vaccinate...AIM: To explore dendritic cells (DCs) multiple functions in immune modulation. METHODS: We used bone-marrow derived dendritic cells from BALB/c mice pulsed with pseudo particles from the hepatitis C virus to vaccinate naive BALB/c mice. Hepatitis C virus (HCV) pseudo particles consist of the genotype 1b derived envelope proteins E1 and E2, covering a non-HCV core structure. Thus, not a single epitope, but the whole "viral surface" induces immunogenicity. For vaccination, mature and activated DC were injected subcutaneously twice. RESULTS: Humoral and cellular immune responses measured by enzyme-linked immunosorbent assay and interferon-gamma enzyme-linked immunosorbent spot test showed antibody production as well as T-cellsdirected against HCV. Furthermore, T-cell responses confi rmed two highly immunogenic regions in E1 and E2 outside the hypervariable region 1. CONCLUSION: Our results indicate dendritic cells as a promising vaccination model for HCV infection that should be evaluated further.展开更多
The precise etiology and reasons for the increase in incidence of autoimmune disorders still remain unclear, and although both genetic and environmental factors have been proven to shape individual predisposition, it ...The precise etiology and reasons for the increase in incidence of autoimmune disorders still remain unclear, and although both genetic and environmental factors have been proven to shape individual predisposition, it is not known which of the factors, if not both, is responsible for the boom observed during the last decades. In order to establish whether a higher frequency of autoimmune-predisposing alleles may explain this increase we took advantage of ancient DNA methodology to establish the genetic predisposition, conferred by cytotoxic T lymphocyte associated antigen-4 （CTLA4） ＋49A/G and human leukocyte antigens （HLA） DQBI^57, in population inhabiting Poland in the Middle Ages. After successful typing of 42 individuals from a 12th-14th＇s century archeological burial site, we found that frequencies of the predisposing alleles in the medieval population were higher than they are at present, suggesting thus that the recently observed incidence increase results most probably from factors of other than genetic nature.展开更多
In order to quantitate the bovine immunodeficiency virus line （BIVL） was established by transfecting baby hamster kidney （BIV） cells infection in vitro, a BIV indicator cell with reporter plasmids containing the f...In order to quantitate the bovine immunodeficiency virus line （BIVL） was established by transfecting baby hamster kidney （BIV） cells infection in vitro, a BIV indicator cell with reporter plasmids containing the firefly luciferase gene driven by a BIV long terminal repeat promoter. The BIV activates promoter activity of the LTR to express luciferase upon infection. BIV infection could therefore by quantified by detection of luciferase activity. Compared to standard assays used to detect BIV infection, the BIVL-based assay is 10 times more sensitive than the the CPE-based assay, and has similar sensitivity with the viral capsid protein Western blot assay BIV indicator cell line could detect BIV infection specifically. Luciferase activity of BIV infected BIVL cells showed a time dependent manner, and 60 h post infection is the optimal time to detect BIV infection. Luciferase activity of BIVL cells correlates with the BIV capsid protein expression. Moreover, a linear relationship was found between MOI and the activated intensity of luciferase expression. In brief, the BIV indicator cell line is an easy, robust and quantitive method for monitoring BIV infection.展开更多
Objective To study the selective toxicity of immunotoxin (IT) on T cells in cord blood and simultaneously determine its effect on hematopoietic progenitor cells Methods The percentage of CD 5 and CD 8 T c...Objective To study the selective toxicity of immunotoxin (IT) on T cells in cord blood and simultaneously determine its effect on hematopoietic progenitor cells Methods The percentage of CD 5 and CD 8 T cell subsets in cord blood (CB) and bone marrow (BM) as well as peripheral blood (PB) was measured by immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti alkaline phosphatase (APAAP complexes) One way mixed lymphocyte cultures (MLC) were performed to compare the proliferative response of CB with that of PB The proliferative capability of cord blood T cells and T lymphocyte transformation capacity were evaluated in the presence of anti CD 8 or anti CD 5 immunotoxin by one way MLC and colorimetric MTT (tetrazolium) assay, respectively The effect of IT on the growth of hematopoietic progenitor cell of colony forming unit granulocyte and macrophage (CFU GM), burst forming unit erythroid(BFU E), multipotential hemotapoietic progenitors (CFU Mix) from CB were estimated by colony forming assays Results A certain proportion of CD 5 and CD 8 T cells existed in CB The alloproliferative capacity of CB was similar to that of PB CD 5: Ricin at a dosage of 1×10 10 -1×10 8 mmol/L and CD 8: Ricin concentration in the range of 1×10 9 -1×10 8 mmol/L effectively decreased both the proliferative capability of T cells in MLC during CB and T cell transformation Over the dosage of 1×10 10 -1×10 9 mmol/L, both kinds of IT didn't obviously affect the growth of hematopoietic progenitor cells Conclusion CD 5: Ricin and CD 8: Ricin may effectively deplete T cells and may not significantly inhibit the function of hemaptopoietic cells at a specific dosage展开更多
文摘Anticancer immunotherapy has undergone a long evolving journey for decades, and has been dramatically applied to mainstream treatments in oncology in recent 5 years. This progress represents an advanced milestone following cytotoxic medicine and targeted therapy. Cellular immunity plays a pivotal role in the immune responses of hosts to tumor antigens. Such immunity is notably suppressed during neoplastic progression due to immuno-editing processes. Cellular immunity can also be selectively reactivated to combat malignancies while exploiting the advantages of contemporary scientific breakthroughs in molecular immunology and genetic engineering. The rapid advancement of cellular immunity-based therapeutic approaches has achieved high efficacy in certain cancer patients. Consequently, the landscape of oncologic medicine and pharmaceutical innovation has transformed recently. In this regard, we present a comprehensive update on clinically established anti-cancer treatments with cell immunity augmentation as the major mechanism of action.
基金Supported by grants of Medical Science and Technology Development Foundation, Jiangsu Province Department of Health (No. H201013)the Program for Postgraduate Research Innovation in University of Jiangsu Province (No. CX10B_054Z)the Project of Youth Foundation in Science and Education of Department of Public Health of Suzhou (2010, No. 4)
文摘Objective： The aim of the study was to investigate whether dendritic cell （DC） precursors, recruited by injection of chemokine ligand 3 （CCL3）, induce enhanced anti-tumor immunity after granulocyte-macrophage colony stimulating factor （GM-CSF） transfection in mice ex vivo. Methods： The 615 mice were injected with CCL3 via the tail vein. Freshly isolated B220–CD11c＋ cells were cultured with cytokines. For adenoviral （Ad）-mediated gene transduction, DCs were transferred AdGM-CSF gene at different ratios of multiplicity of infection （MOI） to determine the optimal gene transfection conditions, and detecting the expression of GM-CSF after transfection. The variation of GM-CSF gene-modified DCs were analyzed by morphological observation, phenotype analysis, and mixed lymphocyte reaction （MLR）. DCs were loaded with gastric cancer antigen obtained by frozen and thawed method. The stimulated DCs vaccination induced T lymphocytes, and the killing effect of T cells to gastric cancer cells was assayed by MTT. INF-γ production was determined with the INF-γ ELISA kit. Results： B220–CD11c＋ cells numbers increased after CCL3 injection. ELISA results showed that after GM-CSF gene modification, DC could produce high level of GM-CSF. When DCs were transferred AdGM-CSF gene at MOI equal to 1：100, GM-CSF level in culture supernatants reached saturation [（130.00 ± 12.61） pg/mL]. After GM-CSF gene-modification, DCs tended to more maturated through morphological observation and were phenotypically identical to typical DC and gained the capacity to stimulate allogeneic T cells. T lymphocytes stimulated with DC transduced with GM-CSF gene showed the specific killing effect on gastric carcinoma cells and produced high level of INF-γ [（1245.00 ± 13.75） pg/mL]. Conclusion： CCL3-recruited DCs modified by adenovirus-transducted GM-CSF could produce high level of GM-CSF, which tended to more maturated, and the capacity of activating allogeneic T lymphocytes proliferation was enhanced greatly. Moreover, they could stimulate specific cytotoxic T lymphocyte （CTL） to gastric cancer ex vivo.
文摘AIM: To investigate the effect of bone marrow-derived monocytes transfected with RNA of CT-26 (a cell line of mouse colon carcinoma) on antitumor immunity. METHODS: Mouse bone marrow-derived monocytes were incubated with mouse granulocyte macrophage colony stimulating factor (mGM-CSF) in vitro, and the purity of monocytes was detected by flow cytometry. Total RNA of CT-26 was obtained by TRIzol's process, and monocytes were transfected by TransMessenger in vitro. The activity of cytotoxic T lymphocytes (CTL) in vivo was estimated by the modified lactate dehydrogenase (LDH) release assay. Changes of tumor size in mice and animal's survival time were observed in different groups. RESULTS: Monocytes from mouse bone marrow were successfully incubated, and the positive rate of CDllb was over 95%. Vaccination of the monocytes transfected with total RNA induced a high level of specific CTL activity in vivo, and made mice resistant to the subsequent challenge of parental tumor cells. In vivo effects induced by monocytes transfected with total RNA were stronger than those induced by monocytes pulsed with tumor cell lysates. CONCLUSION: Antigen presenting cells transfected with total RNA of CT-26 can present endogenous? tumor antigens, activate CTL, and effectively induce specific antitumor immunity.
基金Supported by Youth Foundation of Shanghai Municipal Health Bureau, No. 2008Y087Jiangsu University Clinical Medicine Science and Technology Development Fund, No. JLY20080090
文摘AIM: To assess the significance of phosphatidylinositol 3-kinase (PI3K) in colorectal cancer (CRC) and toxicity of LY294002 in CRC cells with different metastatic abilities. METHODS: Sixty formalin-fixed and paraffin-embedded CRC tumor specimens were investigated. Adjacent normal colonic mucosa specimens from 10 of these cases were selected as controls. PI3K protein was detected by immunohistochemistry and PIK3CA mutations were investigated by gene sequencing analysis. A flowcytometry-based apoptosis detection kit was used to determine PI3K inhibitor-induced apoptosis in CRC cell lines SW480 and SW620. Expression of phosphorylated protein kinase B in CRC cell lines was detected by Western blotting. RESULTS: There was a significant difference in the proportion of primary lesions (30%, 18/60) vs metastatic lesions (46.7%, 28/60) that were positive for PI3K (P < 0.05). Mutations were detected in exon 9 (13.3%) and exon 20 (8.3%). Out of 60 cases, seven mutations were identified: two hotspot mutations, C.1633G>A resulting in E545A, and C.3140A>G resulting in H1047R; two novel missense mutations C.1624G>A and C.3079G>A; and three synonymous mutations (C.1641G>A, C.1581C>T and C.3027T>A). Exposure of SW480 cells to PI3K inhibitor for 48 h resulted in a significant increase of apoptotic cells in a dose-dependent manner [3.2% apoptotic cells in 0 μmol/L, 4.3% in 5 μmol/L, 6.3% in 10 μmol/L (P < 0.05), and 6.7% in 20 μmol/L (P < 0.05)]. Moreover, PI3K inhibitor induced a similar significant increase of apoptotic cells in the SW620 cell line for 48 h [3.3% apoptotic cells in 0 μmol/L, 13.3% in 5 μmol/L (P < 0.01), 19.2% in 10 μmol/L (P < 0.01), and 21.3% in 20 μmol/L (P < 0.01)]. CONCLUSION: High PI3K expression is associated with CRC metastasis. PI3K inhibitor induced apoptosis in CRC cells and displayed strong cytotoxicity for highly metastatic cells. PI3K inhibition may be an effective treatment for CRC.
文摘The effect of monoethylphosphate (MEP, commercial available or synthesized) together with IL-2 on the selective proliferation of human γ~δ T cells in Vitro from peripheral blood mononuclear cells (PBMC) of healthy donors and of cancer patients was investigated. The γ~δ T cells were stimulated by MEP to proliferate in a dose-dependent manner. The effect of synthesized MEP was 10 times greater than that of commercial MEP. When the PBMCs of healthy donors were cultured for 25 d in the medium containing different concentrations of MEP, the total cell number increased about 1000-3000 fold; and the ratio of γ~δ T cells reached to 70-80%. The selective expansion of γ~δ T cells depended on the synergic action of MEP and IL-2. The bulk cultured γ~δ T cells exhibited obvious cytotoxic activities against allogenic tumor cell lines (SQ-5,K562 alld Daudi) and autologous tumor cells. The culture system described here not only offers a simple method for obtaining a large number of γ~δ T cells which may become a new effector in the adoptive immunotherapy, but also provides a useful model for the further studies of the structure and function of γ~δ T cells in vitro.
文摘AIM: To explore dendritic cells (DCs) multiple functions in immune modulation. METHODS: We used bone-marrow derived dendritic cells from BALB/c mice pulsed with pseudo particles from the hepatitis C virus to vaccinate naive BALB/c mice. Hepatitis C virus (HCV) pseudo particles consist of the genotype 1b derived envelope proteins E1 and E2, covering a non-HCV core structure. Thus, not a single epitope, but the whole "viral surface" induces immunogenicity. For vaccination, mature and activated DC were injected subcutaneously twice. RESULTS: Humoral and cellular immune responses measured by enzyme-linked immunosorbent assay and interferon-gamma enzyme-linked immunosorbent spot test showed antibody production as well as T-cellsdirected against HCV. Furthermore, T-cell responses confi rmed two highly immunogenic regions in E1 and E2 outside the hypervariable region 1. CONCLUSION: Our results indicate dendritic cells as a promising vaccination model for HCV infection that should be evaluated further.
基金Project (No. 3 P05E 055 25) supported by the Ministry of Education and Science of Poland
文摘The precise etiology and reasons for the increase in incidence of autoimmune disorders still remain unclear, and although both genetic and environmental factors have been proven to shape individual predisposition, it is not known which of the factors, if not both, is responsible for the boom observed during the last decades. In order to establish whether a higher frequency of autoimmune-predisposing alleles may explain this increase we took advantage of ancient DNA methodology to establish the genetic predisposition, conferred by cytotoxic T lymphocyte associated antigen-4 （CTLA4） ＋49A/G and human leukocyte antigens （HLA） DQBI^57, in population inhabiting Poland in the Middle Ages. After successful typing of 42 individuals from a 12th-14th＇s century archeological burial site, we found that frequencies of the predisposing alleles in the medieval population were higher than they are at present, suggesting thus that the recently observed incidence increase results most probably from factors of other than genetic nature.
基金The General Foundation of Tianjin Science Committee for Applied Basic Research (08JCZDJC21000)Chinese Ministry of Education (30770081)
文摘In order to quantitate the bovine immunodeficiency virus line （BIVL） was established by transfecting baby hamster kidney （BIV） cells infection in vitro, a BIV indicator cell with reporter plasmids containing the firefly luciferase gene driven by a BIV long terminal repeat promoter. The BIV activates promoter activity of the LTR to express luciferase upon infection. BIV infection could therefore by quantified by detection of luciferase activity. Compared to standard assays used to detect BIV infection, the BIVL-based assay is 10 times more sensitive than the the CPE-based assay, and has similar sensitivity with the viral capsid protein Western blot assay BIV indicator cell line could detect BIV infection specifically. Luciferase activity of BIV infected BIVL cells showed a time dependent manner, and 60 h post infection is the optimal time to detect BIV infection. Luciferase activity of BIVL cells correlates with the BIV capsid protein expression. Moreover, a linear relationship was found between MOI and the activated intensity of luciferase expression. In brief, the BIV indicator cell line is an easy, robust and quantitive method for monitoring BIV infection.
文摘Objective To study the selective toxicity of immunotoxin (IT) on T cells in cord blood and simultaneously determine its effect on hematopoietic progenitor cells Methods The percentage of CD 5 and CD 8 T cell subsets in cord blood (CB) and bone marrow (BM) as well as peripheral blood (PB) was measured by immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti alkaline phosphatase (APAAP complexes) One way mixed lymphocyte cultures (MLC) were performed to compare the proliferative response of CB with that of PB The proliferative capability of cord blood T cells and T lymphocyte transformation capacity were evaluated in the presence of anti CD 8 or anti CD 5 immunotoxin by one way MLC and colorimetric MTT (tetrazolium) assay, respectively The effect of IT on the growth of hematopoietic progenitor cell of colony forming unit granulocyte and macrophage (CFU GM), burst forming unit erythroid(BFU E), multipotential hemotapoietic progenitors (CFU Mix) from CB were estimated by colony forming assays Results A certain proportion of CD 5 and CD 8 T cells existed in CB The alloproliferative capacity of CB was similar to that of PB CD 5: Ricin at a dosage of 1×10 10 -1×10 8 mmol/L and CD 8: Ricin concentration in the range of 1×10 9 -1×10 8 mmol/L effectively decreased both the proliferative capability of T cells in MLC during CB and T cell transformation Over the dosage of 1×10 10 -1×10 9 mmol/L, both kinds of IT didn't obviously affect the growth of hematopoietic progenitor cells Conclusion CD 5: Ricin and CD 8: Ricin may effectively deplete T cells and may not significantly inhibit the function of hemaptopoietic cells at a specific dosage
