Development of NK cell expansion methods using feeder cells from human myelogenous leukemia cell line

BACKGROUND: Natural killer (NK) cells constantly survey surrounding tissues and remove newly generated cancer cells, independent of cancer antigen recognition. Although there have been a number of attempts to apply NK cells for cancer therapy, clinical application has been somewhat limited because of the difficulty in preparing a sufficient number of NK cells. Therefore, ex vivo NK cell expansion is one of the important steps for developing NK cell therapeutics. METHODS: CD3+ depleted lymphocytes were cocultured with IL-2 and with feeder cells (peripheral blood mononuclear cells [PBMCs], K562, and Jurkat) for 15 days. Expanded NK cells were tested for cytotoxicity against cancer cell lines. RESULTS: We compared feeder activities of three different cells-PBMC, K562, and Jurkat. K562 expanded NK cells by almost 20 fold and also showed powerful cytotoxic activity against cancer cells. K562-NK cells remarkably expressed the NK cell activation receptors, NKG2D, and DNAM-1. K562-NK cells exhibited more than two-fold production of cytotoxic granules compared with Jurkat-NK cells, producing more perforin and granzyme B than naive NK cells. CONCLUSION: Our findings suggest that K562 are more efficient feeder cells than Jurkat or PBMCs. K562 feeder cells expanded NK cells by almost 20 fold and showed powerful cytotoxic activity against cancer cells. We herein propose an intriguing approach for a design of NK cell expansion.

Hearing Outcomes According to the Types of Mastoidectomy: A Comparison between Canal Wall Up and Canal Wall Down Mastoidectomy

OBJECTIVES: The aim of this study was to compare the hearing outcomes between canal wall up mastoidectmy (CWUM) and canal wall down mastoidectmy (CWDM). METHODS: One hundred seventy one chronic suppurative otitis media (CSOM) patients were enrolled in this retrospective study. The patients who underwent the second staged ossiculoplasty at least 6 months after mastoidectomy and who had an intact, well aerated tympanic cavity as well as intact mobile stapes at the time of operation were selected from the medical record. Based on the type of mastoid surgery, the patients were categorized into two groups: the CWUM (n=38) and CWDM groups (n=133). The hearing results of the CWUM and CWDM groups were compared using the pre- and post-operative air-bone gap (ABG) at 3 months after ossiculoplasty. RESULTS: The preoperative ABG in both groups (CWUM and CWDM) were 28.4+/-15.6 dB and 31.8+/-14.5 dB, respectively (P=0.18). Both groups didn't show any significant difference (10.9 dB vs. 13.5 dB, respectively) (P=0.21) for the postoperative ABG closure. The proportion of patients with an ABG less than 20 dB was 58.6% of the CWDM patients and 68.4% of the CWUM patients (P=0.25). CONCLUSION: The type of mastoid surgery (CWUM and CWDM) did not affect the hearing results of CSOM patients. When choosing the type of mastoidectomy procedure for CSOM surgery, the hearing outcomes are basically the same for both types of procedure.

A Case of Neurovascular Cross-compression of the Eighth Cranial Nerve Representing Longstanding Uncompensated Vestibular Hypofunction / 대한평형의학회지

The neurovascular cross-compression (NVCC) of the eighth cranial nerve (CN) is a clinical entity with symptoms of recurrent vertigo or tinnitus. Although the diagnostic criteria have been defined, the precise clinical presentation and pathomechanism have not been clarified. The treatment response to the carbamazepine; drug of choice for first line medical treatment, has been considered as one of the diagnostic criteria. Herein, we present a case of chronic uncompensated unilateral vestibular hypofunction who responded dramatically to carbamazepine medication. A 55 year-old male admitted to the hospital with symptoms of recurrent oscillopsia and headache for more than 7 years. His symptoms were aggravated by positional changes. Vestibular function tests showed spontaneous nystagmus, canal paresis on caloric test and vestibular dysfunction on dynamic posturography, which represented unilateral uncompensated vestibular hypofunction. Although his symptom was not relived by vestibular rehabilitation, he was treated with carbamazepine. A long standing uncompensated unilateral vestibular hypofunction without any auditory symptoms could be one of the clinical presentations in NVCC of the eighth CN.

Production of TGF-beta1 as a Mechanism for Defective Antigen-presenting Cell Function of Macrophages Generated in vitro with M-CSF

BACKGROUND: Macrophages generated in vitro using macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 from bone marrow cells (BM-Mp) are defective in antigen presenting cell (APC) function as shown by their ability to induce the proliferation of anti-CD3 mAb-primed syngeneic T cells. However, they do express major histocompatibility (MHC) class I and II molecules, accessory molecules and intracellular adhesion molecules. Here we demonstrate that the defective APC function of macrophages is mainly due to production of TGF-beta1 by BM-Mp. METHODS: Microarray analysis showed that TGF-beta1 was highly expressed in BM-Mp, compared to a macrophage cell line, B6D, which exerted efficient APC function. Production of TGF-beta1 by BM-Mp was confirmed by neutralization experiments of TGF-beta1 as well as by real time-polymerase chain reaction (PCR). RESULTS: Addition of anti-TGF-beta1 monoclonal antibody to cultures of BM-Mp and anti-CD3 mAb-primed syngeneic T cells efficiently induced the proliferation of syngeneic T cells. Conversely, the APC function of B6D cells was almost completely suppressed by addition of TGF-beta1. Quantitative real time-PCR analysis also confirmed the enhanced expression of TGF-beta1 in BM-Mp. CONCLUSION: The defective APC function of macrophages generated in vitro with M-CSF and IL-6 was mainly due to the production of TGF-beta1 by macrophages.

Production of TGF-beta1 as a Mechanism for Defective Antigen-presenting Cell Function of Macrophages Generated in vitro with M-CSF

BACKGROUND: Macrophages generated in vitro using macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 from bone marrow cells (BM-Mp) are defective in antigen presenting cell (APC) function as shown by their ability to induce the proliferation of anti-CD3 mAb-primed syngeneic T cells. However, they do express major histocompatibility (MHC) class I and II molecules, accessory molecules and intracellular adhesion molecules. Here we demonstrate that the defective APC function of macrophages is mainly due to production of TGF-beta1 by BM-Mp. METHODS: Microarray analysis showed that TGF-beta1 was highly expressed in BM-Mp, compared to a macrophage cell line, B6D, which exerted efficient APC function. Production of TGF-beta1 by BM-Mp was confirmed by neutralization experiments of TGF-beta1 as well as by real time-polymerase chain reaction (PCR). RESULTS: Addition of anti-TGF-beta1 monoclonal antibody to cultures of BM-Mp and anti-CD3 mAb-primed syngeneic T cells efficiently induced the proliferation of syngeneic T cells. Conversely, the APC function of B6D cells was almost completely suppressed by addition of TGF-beta1. Quantitative real time-PCR analysis also confirmed the enhanced expression of TGF-beta1 in BM-Mp. CONCLUSION: The defective APC function of macrophages generated in vitro with M-CSF and IL-6 was mainly due to the production of TGF-beta1 by macrophages.