• IMMUNE NETWORK
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• 제23권1호
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• pp.8.1-8.13
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• 2023

CD8⁺ T cells are activated by TCRs that recognize specific cognate Ags, while NK-cell activation is regulated by a balance between signals from germline-encoded activating and inhibitory NK receptors. Through these different processes of Ag recognition, CD8⁺ T cells and NK cells play distinct roles as adaptive and innate immune cells, respectively. However, some human CD8⁺ T cells have been found to express activating or inhibitory NK receptors. CD8⁺ T-cell populations expressing NK receptors straddle the innate-adaptive boundary with their innate-like features. Recent breakthrough technical advances in multi-omics analysis have enabled elucidation of the unique immunologic characteristics of these populations. However, studies have not yet fully clarified the heterogeneity and immunological characteristics of each CD8⁺ T-cell population expressing NK receptors. Here we aimed to review the current knowledge of various CD8⁺ T-cell populations expressing NK receptors, and to pave the way for delineating the landscape and identifying the various roles of these T-cell populations.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.175-180
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• 2007

In order to determine the role of Peyer's patch lymphocytes (PPL) in self-clearing of Cryptosporidium parvum infection in murine models, changes in PPL subsets, their cytokine expression, and in vitro IgG1 and IgA secretions by PPL were observed in primary- and challenge-infected C57BL/6 mice. In primary-infected mice, the percentages of CD4+ T cells, CD8+ T cells, slgA+ B cells, IL-2+ T cells, and $IFN-{\gamma}+$ T cells among the PPL, increased significantly (P < 0.05) on day 10 post-infection (PI). Secretion of IgG1 and IgA in vitro by PPL also increased on day 10 PI. However, all these responses, with the exception of IgG1 and IgA secretions, decreased in challenge-infected mice on day 7 post-challenge (= day 13 PI); their IgG1 and IgA levels were higher (P > 0.05) than those in primary-infected mice. The results suggest that murine PPL play an important role in self-clearing of primary C. parvum infections through proliferation of CD4+, CD8+, IL-2+, and $IFN-{\gamma}+$ T cells, and IgG1 and IgA-secreting 8 cells. In challenge infections, the role of T cells is reduced whereas that of 8 cells secreting IgA appeared to be continuously important.

• 생명과학회지
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• 제22권3호
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• pp.312-317
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• 2012

고강도운동의 지속시간이 백혈구 조성과 T-림프구 활성 보조인자로서의 $CD4^+$와 $CD8^+$수준의 변화 그리고 림프수의 세포사에 미치는 영향을 조사하기 위해 쥐실험을 하였다. 고강도 운동을 매일 20, 60, 그리고 120분 동안 8주간 실시하였다. 혈액내의 총 백혈구 수는 20분간 운동을 했을 때 상승하였고 이것은 다시 120분 까지 대조군의 수준 이하로 감소하였다. 림프구의 수준변화 패턴 역시 운동시간의 영향을 받았으며 그 변화 정도는 총 백혈구의 그것과 유사하였다. 고강도운동을 실시한 쥐의 혈액 내 $CD4^+$와 $CD8^+$의 수준은 운동시간이 120분간 지속될 때까지 변화가 없었기 때문에 T-림프구의 활성에는 영향을 주지 않는 것으로 보인다. 거의 모든 초기단계 및 후기 단계의 림프구의 세포자멸사는 운동시간에 영향을 받지 않았으나 120분간 운동한 그룹에서 후기단계의 림프구 자멸사 수준이 증가되는 것으로 보아 이때 세포노화의 촉진이 일어났으리라 사료된다. 운동시간이 길어질수록 림프구의 괴사 수준이 증가되는 것을 확인 하였고 이에 따라 고강도운동에 의한 림프구 손상과 면역력 저하의 가능성이 예상된다. 본 연구에서 장시간 동안의 고강도 운동은 림프구의 염증관련 기능과 세포 수에 있어서의 손상 등을 일으켜 면역력의 저하를 초래할 수 있다고 보며 따라서 적어도 본 연구조건에 한해서 20분 이상의 고강도운동은 건강유지 차원에서 바람직하지 않다고 판단된다.

• IMMUNE NETWORK
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• 제10권4호
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• pp.126-134
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• 2010

Background: $CD8^+$ T cells contribute to the clearance of Hepatitis B virus (HBV) infection and an insufficient $CD8^+$ T cell response may be one of the major factors leading to chronic HBV infection. Since the HBx antigen of HBV can up-regulate cellular expression of several immunomodulatory molecules, we hypothesized that HBx expression in hepatocytes might affect $CD8^+$ T cell activity. Methods: We analyzed the activation and apoptosis of $CD8^+$ T cells co-cultured with primary hepatocytes rendered capable of expressing HBx by recombinant baculovirus infection. Results: Expression of HBx in hepatocytes induced low production of $interferon-{\gamma}$ and apoptosis of CD8+ T cells, with no effect on CD8 T cell proliferation. However, transcriptional levels of H-2K, ICAM-1 and PD-1 ligand did not correlate with HBx expression in hepatocytes. Conclusion: Our results suggest that HBx may inhibit $CD8^+$ T cell response by regulation of $interferon-{\gamma}$ production and apoptosis.

• Journal of Nutrition and Health
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• 제43권2호
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• pp.152-160
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• 2010

본 연구에서는 노화에 따른 영양 태와 면역지표의 변화를 알아보기 위해 연령대가 다른 성인 여성 총 54명을 대상으로 실시하였다. 연령 이외의 환경적 유전적 차이를 최소화하기 위하여 대부분이 한 가족 내 3세대, 즉 20대인 딸, 40~50대인 어머니, 60세 이상의 할머니들로 구성시켰다. 대상자들의 신체 계측, 식이 섭취 조사, 생화학적 검사를 통해 영양상태를 판정하였고, 면역지표를 평가하기 위해 총 백혈구 수 및 백혈구 백분율을 측정하였다. 또한 세포매개성 면역능력을 측정하기 위해 T ltmphocyte과 CD4 +, CD8 + 그리고 NK cells의 수와 비율을 측정하였으며 체액성 면역지표를 알아보기 위해 면역 글로불린 G, A, M의 농도를 측정하였다. 신체 계측 결과 연령이 증가됨에 따라 평균 체지방 함량은 증가하였고 체내 총 수분량과 근육의 양은 줄어드는 경향을 나타냈다. 각 연령별 영양 섭취 상태를 조사한 결과 20대 여대생군의 경우 열량과 철분을 제외한 다른 영양소의 영양상태는 비교적 양호하였으나 3대 영양소의 열량 섭취 비율 또한 한국인 영양섭취기준과 거의 일치하는 것으로 나타났다. 40~50대 어머니군에서도 철분의 영양 상태가 권장량에 비해 부족하였고, 할머니군에서는 에너지 섭취량은 권장량에 비해 낮은 반면 단백질과 철분의 섭취량은 양호한 것으로 나타났다. 총 백혈구 수 및 백혈구 백분율은 조사 대상자 대부분이 정상 범위에 속해 연령 증가에 따른 유의성이 없었으며, T lymphocyte 및 CD4 +, CD8 +와 NK cells을 조사한 결과 T lymphocyte과 CD4 + T cells은 연령 증가에 따라 유의적 차를 보이지 않는 반면 CD8 + T cells은 연령이 증가할수록 유의적으로 감소하여 CD4 +：CD8 +의 비율이 노화됨에 따라 증가하는 경향을 나타냈고, 전체 lymphocyte 중에서 NK cells과 B lymphocyte 수는 유의적 차를 보이지 않았으나 면역 글로불린 M은 노화에 따라 그 농도가 감소하는데 비해 면역 글로불린 A는 각 군별 유의성이 없었고, 면역 글로불린 G는 어머니군에서 유의적으로 높았다. 영양 면역학은 비교적 최근의 관심 분야이고 더욱이 국내에서 이 분야의 연구는 매우 미흡한 실정이다. 그러므로 급속히 발달하고 있는 면역학 이론의 올바른 이해와 새로운 연구 방법의 신속한 적용, 정확한 연구 결과의 해석으로 좀더 구체적이고 체계적인 연구를 통해 각 영양소가 인체 면역지표에 미치는 구체적 메커니즘을 밝히고 면역능 증진을 위한 생리적 활성을 줄 수 있는 각 영양소의 권장량에 대한 연구가 앞으로 이루어져야 할 것으로 보인다.

• 대한의생명과학회지
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• 제27권4호
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• pp.329-333
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• 2021

We previously identified that tumor cells genetically modified with a 4-1BBL co-stimulatory molecule had anticancer effects in a CT26 mouse colorectal tumor model. To identify the distinction between immune cells in a mouse tumor model treated with tumor cells genetically modified with 4-1BBL or β-gal, we examined the immune cells in CT26-WT, CT26-βgal, and CT26-4-1BBL tumor bearing mice 21 days after tumor cell administration. The CD8+ T cells population in mice treated with tumor cells genetically modified with 4-1BBL was significantly increased on day 21 compared to that of tumor cells genetically modified with β-gal in the spleen and tumor tissue. The CD4+ T cell population was not different between the two mice groups. The Foxp3+CD25^high CD4 T cell population decreased on day 21 in tumor tissues, but the decrease was not significant. We also found that CD8 T cells had pivotal roles in inhibiting tumor growth by treating mice with ant-CD4 and CD8 antibodies. These results suggest that tumor cells genetically modified with 4-1BBL could inhibit tumor growth by affecting on CD8 T lymphocytes.

• 한국임상수의학회지
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• 제40권3호
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• pp.203-208
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• 2023

A 13-year-old neutered male mixed-breed dog presented with generalized lymphadenopathy and erythematous cutaneous lesions in the ear pinnae. Fine-needle aspiration cytology of the lymph nodes revealed small to intermediate lymphocytes with a "hand mirror" configuration as the predominant cell type. Histopathological analysis of the lymph node showed an infiltrate of CD3-positive small lymphocytes compressing the follicles against the capsule owing to neoplastic cell expansion. Flow cytometric analysis revealed a homogeneous population of CD3+/CD4-/CD5+/CD8-/CD21+/CD34-/CD45- cells in both the peripheral blood and aspirated lymph nodes, which supports the diagnosis of T-zone lymphoma. Laboratory tests revealed lymphocytosis (14,144 cells/µL) in the peripheral blood. However, contrary to expectations, the bone marrow examination revealed no evidence of lymphocytic infiltration. T-zone lymphoma is an indolent lymphoma with a long survival period, and knowledge of its characteristics may affect disease staging and prognosis evaluation. Therefore, peripheral blood count as a sole screening tool for bone marrow metastasis should be used with caution.

• 약학회지
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• 제46권3호
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• pp.213-218
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• 2002

In the previous report, we described the in vivo antitumor activity of PJ-4, a protein-polysaccharide fraction prepared from the culture filtrate of an insect-born fungus, Paecilomyces tenuipes DGUM 32001. In the present study, we elucidated the immunomodulating activity of PJ-4 on the BALB/c mouse splenic lymphocytes using flow cytometrical techniques. As a result, PJ-4 was found to stimulate the lymphocytes not only to form lymphoblasts but also to express CD25 (IL-2 receptor $\alpha$ chain) molecule, which is well known as a T cell activation marker. More interestingly, its T cell stimulatory activity was more strongly exerted on CD8$^{+}$ T cells than on CD4$^{+}$ T cells. All these data suggest that PJ-4 exerts its antitumor activity at least partly through stimulation of T cells which play major roles in the cell-mediated immune system.tem.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3815-3819
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• 2012

The CD4+CD25+ regulatory T cell (Treg) is a special kind of T cell subset. Studies have showed that Treg cells are involved in a number of physiological processes and pathologic conditions such as autoimmune diseases, transplantation tolerance and cancer. Tregs with unique capacity for immune inhibition can impair anti-tumour immunity and help tumor cells to escape from immune surveillance. The aim of our study was to investigate whether Tregs are involved in hepatocellular carcinoma (HCC). A BABL/C mouse with HCC in situ model was established to evaluate the Treg existence in carcinoma tissues and the changes of Tregs in spleen using flow cytometry and immunohistochemistry methods. Granzyme B expression in carcinoma tissues was analyzed by immunohistochemistry to investigate the tumor local immune status.The proportion of CD4+CD25+/CD4+ spleen lymphocytes of tumor bearing mice ($18.8%{\pm}1.26%$) was found to be significantly higher than that in normal mice ($9.99%{\pm}1.90%$) (P<0.01 ). Immunohistochemistry of spleen tissue also confirmed that there was an increase in Treg in tumor-bearing mice, while in carcinomas it showed Treg cells to be present in tumor infiltrating lymphocyte areas while Granzyme B was rarely observed. Anti-tumour immunity was suppressed, and this might be associated with the increase of Tregs. Our observations suggest that the CD4+CD25+Treg/CD4+ proportion in spleen lymphocytes can be a sensitive index to evaluate the change of Tregs in hepatocellular carcinoma mice and the Treg may be a promising therapeutic target for cancer.

• IMMUNE NETWORK
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• 제23권1호
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• pp.9.1-9.15
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• 2023

Cancer immunotherapies continue to face numerous obstacles in the successful treatment of solid malignancies. While immunotherapy has emerged as an extremely effective treatment option for hematologic malignancies, it is largely ineffective against solid tumors due in part to metabolic challenges present in the tumor microenvironment (TME). Tumor-infiltrating CD8⁺ T cells face fierce competition with cancer cells for limited nutrients. The strong metabolic suppression in the TME often leads to impaired T-cell recruitment to the tumor site and hyporesponsive effector functions via T-cell exhaustion. Growing evidence suggests that mitochondria play a key role in CD8⁺ T-cell activation, migration, effector functions, and persistence in tumors. Therefore, targeting the mitochondrial metabolism of adoptively transferred T cells has the potential to greatly improve the effectiveness of cancer immunotherapies in treating solid malignancies.