OPTIMIZING A LIMITING DILUTION CULTURE SYSTEM FOR QUANTIFYING THE FREQUENCY OF INTERLEUKIN-2-PRODUCING ALLOREACTIVE T HELPER LYMPHOCYTES1

Purpose: Targeting programmed death-ligand 1 (PD-L1) may be an effective intervention for osteosarcoma and PD-L1 expression is controlled by diverse regulatory factors. Low-density lipoprotein receptor-related protein 8 (LRP8) regulates osteoblast differentiation and it is unclear whether and how LRP8 could contribute to osteosarcoma pathogenesis. In this study, we investigated the LRP8/signal transducer and activator of transcription 3 (STAT3)/PD-L1 network in osteosarcoma. Methods: The expression of LRP8, STAT3, and PD-L1 was measured in osteosarcoma tissues and paired normal tissues. The effects of LRP8 on STAT3 and PD-L1 expression were investigated in an osteosarcoma cell line. The effects on immunosuppression were investigated in an in vitro co-culture system with Jurkat cell line and osteosarcoma cell line. The effects of LRP8 were blocked by a LRP8 neutralizing antibody, dominant-negative STAT3, or STAT3 inhibitor. Results: LRP8 was overexpressed in osteosarcoma compared to normal tissues and its level was correlated with phospho-STAT3 (p-STAT3) level in osteosarcoma tissues. In osteosarcoma cell lines, LRP8 increased p-STAT3 level and promoted nuclear translocation of STAT3. STAT3 activation also increased PD-L1 mRNA, protein, and promoter activity. In addition, LRP8 enhanced PD-L1 expression via STAT3. In a co-culture system, LRP8 overexpression in an osteosarcoma cell line impaired viability and interleukin-2 secretion of Jurkat cells and induced apoptosis of Jurkat cells. The effects of LRP8 could be blocked by neutralizing LRP8 antibody or STAT3 inhibitor. Blocking LRP8 inhibits proliferation and induces apoptosis of osteosarcoma cells. Conclusions: Our results provide evidence for a novel regulation network of LRP8/STAT3/PD-L1 in osteosarcoma and LRP8 may be a potential therapeutic target in osteosarcoma.

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Differentiation of natural killer (NK) cells from human primitive marrow progenitors in a stroma-based long-term culture system: identification of a CD34+7+ NK progenitor

Blood ◽

10.1182/blood.v83.9.2594.2594 ◽

1994 ◽

Vol 83 (9) ◽

pp. 2594-2601 ◽

Cited By ~ 146

Author(s):

JS Miller ◽

KA Alley ◽

P McGlave

Keyword(s):

Nk Cells ◽

Natural Killer ◽

Culture System ◽

Interleukin 2 ◽

Early Event ◽

Hematopoietic Progenitors ◽

Long Term Culture ◽

Lineage Differentiation ◽

Marrow Stroma

Abstract We have recently described a marrow stroma-dependent long-term culture system that supports differentiation of CD34+ human marrow primitive progenitors into natural killer (NK) cells. We postulate that CD7 expression may be an early event in commitment of hematopoietic progenitors to the NK lineage. Here we compare the characteristics of CD34+7- and CD34+7+ marrow cells cultivated in the stroma-based NK culture system. These CD34+ populations were further compared with a marrow derived, more committed, CD34–7+ progenitor to emphasize the continuum of NK development and to highlight differences between progenitors in our assays. No progenitor proliferated when plated in media without stroma, underscoring the importance of stroma in NK differentiation. Plating progenitor populations in interleukin-2 containing media directly on preestablished, allogeneic, irradiated marrow stroma for 5 weeks resulted in CD56+CD3- NK cells; however, characteristics of the cultured populations differed. Fold expansion and cloning efficiency of the CD34+7+ population, determined by a functional limiting dilution assay was significantly higher than of the CD34+7- or CD34+7+ populations. This suggests that the CD34+7+ population is highly enriched for an NK progenitor and a possible intermediate in NK lineage differentiation. Further dividing the CD34+7+ population by the relative fluorescence of CD7 into CD34+7+dim and CD34+7+bright populations showed that the CD34+7+bright population exhibited a significantly higher cloning frequency than parallel experiments with CD34+7+dim cells (11.8% +/- 2.4% v 2.4% +/- 0.7%, n = 6; P = .005). Plating of the more primitive CD34+7- population in a transwell system (which separates progenitors from stroma by a microporous membrane) prevents differentiation into NK cells. In contrast, plating of CD34+7+ progenitors in transwells resulted in generation of NK cells. These data suggest that primitive, but not more mature NK progenitors may require direct contact with stroma for the initial differentiation steps. Finally, differentiation of the NK progenitors in this stroma-dependent model results in expression of CD2 not present on any of the starting populations. This observation suggests that marrow stroma can stimulate CD2 expression on NK progenitors in a previously undescribed fashion that may be analogous to the thymic effect on CD2 expression in immature T lymphocytes. These observations identify early steps in the commitment of primitive marrow CD34+ hematopoietic progenitors to a lymphoid lineage and underscore the importance of coexpression of CD7 with CD34 as an early lymphoid commitment characteristic and direct progenitor-stroma interactions in this process.

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Immunomodulatory Activities of Yunzhi and Danshen in Post-treatment Breast Cancer Patients

The American Journal of Chinese Medicine ◽

10.1142/s0192415x05002990 ◽

2005 ◽

Vol 33 (03) ◽

pp. 381-395 ◽

Cited By ~ 50

Author(s):

Chun-Kwok Wong ◽

Yi-Xi Bao ◽

Eliza Lai-Yi Wong ◽

Ping-Chung Leung ◽

Kwok Pui Fung ◽

...

Keyword(s):

Breast Cancer ◽

Body Weight ◽

Cancer Patients ◽

Salvia Miltiorrhiza ◽

Interleukin 2 ◽

Post Treatment ◽

Enzyme Linked Immunosorbent Assay ◽

Breast Cancer Patients ◽

T Helper ◽

The Absolute

Breast cancer is the most common cancer among women worldwide. Discomfort and fatigue are usually arisen from anticancer therapy such as surgery, radiotherapy, chemotherapy, hormonal therapy, or combination therapy, because of the suppressed immunological functions. Yunzhi (Coriolus versicolor) can modulate various immunological functions in vitro, in vivo, and in human clinical trials. Danshen (Salvia miltiorrhiza) has been shown to benefit the circulatory system by its vasodilating and anti-dementia activity. The purpose of this clinical trial was to evaluate the immunomodulatory effects of Yunzhi-Danshen capsules in post-treatment breast cancer patients. Eighty-two patients with breast cancer were recruited to take Yunzhi [50 mg/kg body weight, 100% polysaccharopeptide (PSP)] and Danshen (20 mg/kg body weight) capsules every day for a total of 6 months. EDTA blood samples were collected every 2 months for the investigation of immunological functions. Flow cytometry was used to assess the percentages and absolute counts of human lymphocyte subsets in whole blood. Plasma level of soluble interleukin-2 receptor (sIL-2R) was measured by enzyme-linked immunosorbent assay (ELISA). Results showed that the absolute counts of T-helper lymphocytes (CD4+), the ratio of T-helper (CD4+)/T suppressor and cytotoxic lymphocytes (CD8+), and the percentage and the absolute counts of B-lymphocytes were significantly elevated in patients with breast cancer after taking Yunzhi-Danshen capsules, while plasma sIL-2R concentration was significantly decreased (all p < 0.05). Therefore, the regular oral consumption of Yunzhi-Danshen capsules could be beneficial for promoting immunological function in post-treatment of breast cancer patients.

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