Objective To prepare CD318-specific monoclonal antibodies and evaluate their specificity, affinity, and application in immunological detection, laying the foundation for the development of CD318-targeted antibody drugs. MethodsCD318 protein was expressed and purified, and was used as an antigen to immunize mice, then mice with higher antiserum titers were screened. We prepared CD318-specific monoclonal antibodies through cell fusion and monoclonal screening, and the specificity, affinity, and application of the obtained monoclonal antibodies in immunological assays were evaluated. Then we constructed a CD318/CD3-targeting bispecific antibody and assessed its impact on T-cell cytotoxicity. Results Thirteen monoclonal antibodies were successfully generated, with the hybridoma clone 13-8-G2 exhibiting the highest titer, strongest specificity, and broadest applicability. The antibody was identified as an IgG1 isotype with a kappa light chain. The variable region of the light chain measured 318 bp, while the heavy chain variable region was 357 bp, yielding an affinity constant of approximately 7.68×10⁹. The specificity of CD318 was confirmed using flow cytometry and immunofluorescence assays. Additionally, a CD318/CD3-targeting bispecific antibody was constructed using the variable regions of this CD318 monoclonal antibody, which demonstrated enhanced T-cell cytotoxicity. Conclusion High-affinity and highly specific CD318 monoclonal antibodies were successfully prepared, laying a foundation for the development of therapeutic antibodies targeting CD318.
Animals ; Antibodies, Monoclonal/biosynthesis* ; Mice ; Antibodies, Bispecific/immunology* ; Humans ; Mice, Inbred BALB C ; Antibody Specificity/immunology* ; CD3 Complex/immunology* ; Antigens, CD/genetics* ; T-Lymphocytes/immunology* ; Hybridomas/immunology* ; Female

Novel biologics that redirect cytotoxic T lymphocytes (CTLs) to kill tumor cells bearing a tumor associated antigen hold great promise in the clinic. However, the ability to safely and potently target CD3 on CTL toward tumor associated antigens (TAA) expressed on tumor cells remains a challenge of both technology and biology. Herein we describe the use of a Half DVD-Ig format that can redirect CTL to kill tumor cells. Notably, Half DVD-Ig molecules that are monovalent for each specificity demonstrated reduced non-specific CTL activation and conditional CTL activation upon binding to TAA compared to intact tetravalent DVD-Ig molecules that are bivalent for each specificity, while maintaining good drug like properties and appropriate PK properties.
Animals ; Antibodies, Bispecific ; immunology ; Antibodies, Monoclonal ; immunology ; pharmacokinetics ; CD3 Complex ; metabolism ; Cell Line, Tumor ; Cytotoxicity, Immunologic ; ErbB Receptors ; metabolism ; Female ; Humans ; Lymphocyte Activation ; immunology ; Mice, SCID ; Neoplasms ; immunology ; pathology ; Rats, Sprague-Dawley ; T-Lymphocytes, Cytotoxic ; immunology

OBJECTIVETo develop an easy method to amplify natural killer (NK) cells by using mononuclear cells in vitro, so as to lay the basis for NK cell therapy.

METHODSUmbilical cord blood from 3 healthy full-term pregnant women was collected, and the peripheral blood mononuclear cells (PBMNC) were harvested by density gradient centrifugation. Each sample of PBMNC was divided into 3 groups: CD16mAb, CD3 mAb and CD16mAb+CD3mAb- groups. The culture flasks were pre-coated with CD16, CD3 or CD3 plus CD16 mAb. The PBMNCs were cultured in serum-free media containing autologous plasma, recombinant human IL-2, IL-15 and IL-21 for 14 days under the same conditions. The total viable cell count was calculated. Flow cytometry was used to determine the ratio of CD56CD3 cells, MTT assay was used to measure the killing rate of NK cells under different effector/target ratio, by using the K562 cells as the target cells.

RESULTSAfter 14 days of culture, the total cell numbers of CD16mAb, CD3mAb and CD16mAb +CD3mAb groups increased by 45.71±5.54, 87.41±19.77 and 4.88±51.84 times, respectively, and those of CD3mAb group were significantly higher than the other 2 groups (P<0.05). The ratio of CD56CD3 cells before culture was 0.1663±0.0201, which was 0.8167±0.0500, 0.8077±0.0589 and 0.8077±0.0273 after incubation with CD16mAb, CD3mAb and CD16mAb +CD3mAb for 14 days, respectively (P>0.05). MTT test showed that the killing efficiencies were not significantly different among the 3 groups when the effector/target ratios were 1:1, 5:1 and 10:1 (P>0.05).

CONCLUSIONBy incubation with anti-CD3 monoclonal antibody, IL-2, IL-15 and IL-21, the highly purified NK cells can be obtained from mononucleated cells, thus providing a simple method for NK cell therapy.

CD3 Complex ; CD56 Antigen ; Cell Culture Techniques ; Cells, Cultured ; Female ; Humans ; Killer Cells, Natural ; Leukocytes, Mononuclear ; Pregnancy

The generation of T cells with maximal anti-tumor activities will significantly impact the field of T-cell-based adoptive immunotherapy. In this report, we found that OKT3/IL-2-stimulated T cells were phenotypically more heterogeneous, with enhanced anti-tumor activity in vitro and when locally administered in a solid tumor mouse model. To further improve the OKT3/IL-2-based T cell manufacturing procedure, we developed a novel T cell stimulation and expansion method in which peripheral blood mononuclear cells were electroporated with mRNA encoding a chimeric membrane protein consisting of a single-chain variable fragment against CD3 and the intracellular domains of CD28 and 4-1BB (OKT3-28BB). The expanded T cells were phenotypically and functionally similar to T cells expanded by OKT3/IL-2. Moreover, co-electroporation of CD86 and 4-1BBL could further change the phenotype and enhance the in vivo anti-tumor activity. Although T cells expanded by the co-electroporation of OKT3-28BB with CD86 and 4-1BBL showed an increased central memory phenotype, the T cells still maintained tumor lytic activities as potent as those of OKT3/IL-2 or OKT3-28BB-stimulated T cells. In different tumor mouse models, T cells expanded by OKT3-28BB RNA electroporation showed anti-tumor activities superior to those of OKT3/IL-2 T cells. Hence, T cells with both a less differentiated phenotype and potent tumor killing ability can be generated by RNA electroporation, and this T cell manufacturing procedure can be further optimized by simply co-delivering other splices of RNA, thus providing a simple and cost-effective method for generating high-quality T cells for adoptive immunotherapy.
Animals ; CD28 Antigens ; genetics ; immunology ; Electroporation ; Humans ; Immunity, Cellular ; Interleukin-2 ; immunology ; K562 Cells ; Mice ; Muromonab-CD3 ; immunology ; Neoplasms, Experimental ; genetics ; immunology ; pathology ; RNA, Messenger ; genetics ; immunology ; T-Lymphocytes ; immunology ; Tumor Necrosis Factor Receptor Superfamily, Member 9 ; genetics ; immunology

OBJECTIVETo explore the change in the expression of extracellular heat shock protein 70 (eHSP70) and interleukin 2 (IL-2) and their correlation in intestine of rats with severe scald injury, and to observe the effects of eHSP70 on CD3(+) T lymphocytes in Peyer's patch of intestine in rats with severe scald injury in vitro.

METHODS(1) Sixty male SD rats were divided into normal control group (NC, n=10, only anesthetized) and scald group (S, n=50) according to the random number table. Rats in scald group were inflicted with 30% total body surface area full-thickness scald on the back. Ten rats from group NC immediately after anesthetization and 10 rats from group S at post injury hour (PIH) 3, 6, 12, 24, 48 were sacrificed to harvest their small intestines. The expressions of eHSP70 and IL-2 were determined with enzyme-linked immunosorbent assay (ELISA), and their correlation was analyzed. (2) Another 2 male SD rats were inflicted with the same injury as above. At PIH 12, CD3(+) T lymphocytes in Peyer's patch of small intestine were isolated and cultured with RPMI 1640 nutrient solution containing 10% fetal bovine serum. Cells were divided into blank control group (BC) and 5, 10, 20 μg/mL eHSP70 groups according to the random number table, with 6 wells in each group. Cells in group BC didn't receive any other treatment, while cells in the latter three groups were treated with corresponding mass concentration of recombinant rat eHSP70. After being cultured for 48 hours, the proportions of Th1 and Th2 in CD3(+) T lymphocytes, and the apoptosis rate of CD3(+) T lymphocytes were detected with flow cytometer, while the expressions of IL-2 and IL-10 in culture supernatant of cells were determined with ELISA. The cell experiments were repeated for 10 times. Data were processed with one-way analysis of variance, Kruskal-Wallis rank sum test, SNK-q test, and Pearson correlation analysis.

RESULTS(1) Compared with those in group NC [(1 278±135) and (48.6±4.9) ng/mg], the levels of eHSP70 [(728±93), (412±31), (314±21), (528±40), (1 028±97) ng/mg] and IL-2 [(38.6±2.3), (32.3±1.0), (25.3±3.6), (33.9±4.1), (44.3±2.6) ng/mg] in intestine of rats in group S obviously decreased at PIH 3, 6, 12, 24, 48 (with q values from 3.48 to 5.32, P values below 0.05), reaching the nadir both at PIH 12, with a significantly positive correlation between the level of IL-2 and the level of eHSP70 (r=0.920, P<0.01). (2) Compared with those in group BC [(8.6±1.1)% and (3.75±0.45)%], the proportion of Th1 obviously increased [(11.3±2.1)%, (15.7±1.8)%, (10.8±1.5)%, with q values from 2.97 to 4.57, P values below 0.05], while the proportion of Th2 obviously decreased [(2.39±0.38)%, (1.05±0.23)%, (2.67±0.26)%, with q values from 2.48 to 4.32, P values below 0.05] in CD3(+) T lymphocytes of rats in 5, 10, 20 μg/mL eHSP70 groups. Compared with those in group BC [(34.3±2.2)% and (254±16) pg/mL], the apoptosis rate of CD3(+) T lymphocytes obviously decreased [(26.1±2.6)%, (20.7±1.5)%, (31.5±2.4)%, with q values from 3.47 to 4.95, P values below 0.05], while the level of IL-2 obviously increased [(417±22), (587±19), (307±27) pg/mL, with q values from 3.02 to 4.98, P values below 0.05] in culture supernatant of CD3(+) T lymphocytes of rats in 5, 10, 20 μg/mL eHSP70 groups. There was no significant difference in the level of IL-10 in culture supernatant of CD3(+) T lymphocytes of rats among the four groups (F=2.12, P>0.05).

CONCLUSIONSThe expressions of eHSP70 and IL-2 in intestine of rats are decreased after severe scald, with a obviously positive correlation between them. eHSP70 can promote the differentiation of CD3(+) T lymphocytes in Th1 orientation, decrease the apoptosis rate of the cells, and promote the release of IL-2 of cells in Peyer's patch of intestine in rats with severe scald injury in vitro.

Animals ; Burns ; metabolism ; CD3 Complex ; metabolism ; Enzyme-Linked Immunosorbent Assay ; HSP70 Heat-Shock Proteins ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-2 ; metabolism ; Intestine, Small ; metabolism ; Male ; Peyer's Patches ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Th1 Cells ; cytology

BACKGROUNDAltered immunoresponse is associated with tumorigenesis and cancer progression. This study assessed the levels of tumor-infiltrating CD3 + or CD8 + T lymphocytes and interleukin-2 (IL-2) protein in radically resected non-small cell lung cancer (NSCLC) tissues to predict overall survival (OS) of the patients.

METHODSParaffin-embedded tissue specimens from 129 NSCLC patients were retrospectively collected for immunostaining of CD8 + , CD3 + , and IL-2 expression. Clinicopathological and survival data were collected and analyzed using the Chi-squared test, Kaplan-Meier curves, and the log-rank test or the Cox regression model.

RESULTSThe data showed a significant inverse association between CD8 + T lymphocyte levels and IL-2 expression (r = -0.927; P = 0.000) and between the levels of CD8 + and CD3 + T lymphocytes (r = -0.722; P = 0.000), but a positive association between CD3 + T lymphocyte levels and IL-2 expression (r = 0.781; P = 0.000) in NSCLC tissues. Furthermore, the levels of CD3 + and CD8 + T lymphocytes and IL-2 expression were associated with tumor stage (P = 0.023, 0.006, and 0.031, respectively) and the level of CD8 + T lymphocytes was associated with the patient gender (P = 0.024). In addition, the levels of CD8 + T lymphocytes were associated with an unfavorable 5-year OS, whereas patients with high levels of CD3 + T lymphocytes in tumor lesions and IL-2-expressing tumors had significantly better 5-year OS rates than patients with low levels.

CONCLUSIONSThe levels of CD8 + T cells in tumor lesions and IL-2 expression were both independent predictors of OS for these NSCLC patients. Thus, the detection of tumor-infiltrating CD3 + or CD8 + T lymphocytes and IL-2 expression could be useful to predict the prognosis of radically resected NSCLC patients.

CD3 Complex ; metabolism ; CD8-Positive T-Lymphocytes ; metabolism ; Female ; Humans ; Immunohistochemistry ; Interleukin-2 ; metabolism ; Lung Neoplasms ; immunology ; metabolism ; Lymphocytes, Tumor-Infiltrating ; metabolism ; Male ; Prognosis

OBJECTIVETo investigate the therapeutic effects of Qingre Quyu Granule (QQG) on the patients with severe carotid stenosis, and to explore the mechanism of it.

METHODSNinety-six patients with severe carotid stenosis were enrolled in the study and were classified into a QQG group (n=48) and a control group (n=48) randomly using consecutively numbered envelopes. The patients in the QQG group were given QQG and Western medicine, those in the control group were given Western medicine merely, the course of treatment was 16 weeks. All patients went through endarterectomy after treatment. Plaques were subjected to the analysis of CD3, CD68, soluble intercellular adhesion molecule 1 (ICAM-1), matrix metalloprotease-9 (MMP-9), CD40L, tenascin-C, and collagen content lipid content by immunohistochemistry or polarized light analysis.

RESULTSBy the end of experiment, the expressions of CD3, CD68, ICAM-1, MMP9, CD40L and tenascin-C on the plaques were statistically significant lower in the QQG group compared with the control group(P<0.01). The lipid content of the plaque was also significantly lower in the QQG group compared with the control group (P<0.01). The interstitial collagen in the tissue sections of the plaques was also significantly higher in the QQG group in comparison with the control group (P<0.01).

CONCLUSIONQQG could stabilize carotid artery plaques through inhibiting pro-inflammation factors and restraining the tenascin-C and MMP9 pathway.

Aged ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; CD3 Complex ; metabolism ; CD40 Ligand ; metabolism ; Carotid Arteries ; metabolism ; pathology ; Carotid Stenosis ; blood ; complications ; drug therapy ; Collagen ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Humans ; Immunohistochemistry ; Inflammation ; complications ; pathology ; Intercellular Adhesion Molecule-1 ; metabolism ; Lipids ; blood ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Plaque, Atherosclerotic ; blood ; complications ; drug therapy ; Tenascin ; metabolism

Antigens, CD ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; metabolism ; CD3 Complex ; metabolism ; Cells, Cultured ; Humans ; Kinetics ; Lectins, C-Type ; metabolism ; Lymphocyte Activation ; T-Lymphocyte Subsets ; drug effects ; immunology ; metabolism

OBJECTIVETo observe if VIR576, an 20-mer peptide derived from the C-proximal subfragment of a1-antitrypsin (a1-AT) which inhibits human immunodeficiency virus type 1 (HIV-1) entry into the target cells by interacting with fusion peptide (FP), can also directly inhibit CD4(+) T cell activation in vitro.

METHODSSplenocytes isolated from DO11.10 OVA Tg mice were stimulated with ovalbumin or concanavalin A to test the effects of VIR576 on antigen-specific or non-antigen-specific T cell activation. Both primary CD4(+)CD25(-) T cells from DO11.10 mice and CD4(+) T cell line A2b were activated with specific antigens to evaluate the effects of VIR576.

RESULTSVIR576 inhibited antigen-specific splenocyte activation but had no significant effect on non-antigen-specific T-cell activation, which bypassed the crosstalk between the CD3-signaling complex and TCR. We furthermore observed that VIR576 could also down-regulate antigen-specific CD4(+) T-cell activation.

CONCLUSIONSGiven the high susceptibility of activated CD4(+) T cells in the mucosa to HIV-1 infection, the inhibitory effects of VIR576 on both HIV entry into the target cells and CD4(+) T-cell activation suggest the potential of VIR576 as a microbicide for prevention of sexual transmission of HIV.

Animals ; CD3 Complex ; CD4-Positive T-Lymphocytes ; drug effects ; HIV Fusion Inhibitors ; pharmacology ; HIV-1 ; Lymphocyte Activation ; drug effects ; Mice ; Mice, Transgenic ; Ovalbumin ; Peptide Fragments ; pharmacology ; alpha 1-Antitrypsin ; pharmacology

BACKGROUNDB7-H3 has been widely studied in the context of tumor progression in recent years, and behaves as a tumor cell marker in a variety of tumors including colorectal carcinoma. The mechanism of B7-H3 in tumor progression is complicated and not clear yet. Studies have revealed that B7 family molecules are expressed on infiltrated lymphocytes as well as tumor cells in tumor microenvironment, which indicates that different expression pattern may lead to different clinical outcomes.

METHODSThe expression of B7-H3 was detected in tissues of 98 colorectal carcinoma patients by using immunohistochemistry. Then the expression of B7-H3 on CD3(+) T lymphocytes isolated from fresh cancer tissues of 12 colorectal carcinoma patients was analyzed by flow cytometry assay. The relationship between the expression of B7-H3 on CD3(+) T lymphocytes and patients' clinical pathological parameters was demonstrated with statistical analysis.

RESULTSPatients with more CD3(+) T cell infiltration survived much longer than patients with less CD3(+) T cell infiltration (P < 0.05); B7-H3 was highly expressed by infiltrating CD3(+) T lymphocytes in colorectal carcinoma tissues. The expression of B7-H3 was found to be significantly related with lymph node metastasis status (P < 0.05), but not with the patient's gender, age, tumor size, differentiation degree, depth of tumor invasion, Dukes' stage, distant metastasis and whether or not mucinous adenocarcinoma was present (P > 0.05). Moreover, the survival time of patients with low expression of B7-H3 was obviously longer than those of high B7-H3 expression patients, but the seven-year survival rate showed no difference between the high and low B7-H3 expression patients (P > 0.05).

CONCLUSIONThe negative costimulatory molecule B7-H3 on infiltrating CD3(+) T lymphocytes in colorectal carcinoma bears importance in the clinical pathological progress and prognosis of colorectal carcinoma.

Adult ; Aged ; B7 Antigens ; analysis ; CD3 Complex ; analysis ; Colorectal Neoplasms ; immunology ; mortality ; pathology ; Female ; Flow Cytometry ; Humans ; Immunohistochemistry ; Lymphocytes, Tumor-Infiltrating ; immunology ; Male ; Middle Aged ; Survival Rate ; T-Lymphocytes ; immunology