一、PBMC細胞計數的現狀
1. 目前,絕大多數的科研工作者仍在使用血球計數板在顯微鏡下進行手工計數PBMCs;

2. 但是顯微鏡下由于白細胞和紅細胞大小非常接近,不能完全區分白細胞和紅細胞;
3. 通過紅細胞的雙凹形形態鑒別紅細胞,需要經驗豐富的操作者,且不停地調焦來鑒別;可想而知要把每個紅細胞鑒別出來,要耗費多長的時間,需要多強的工作量。
PBMC樣本的差異性大
由于個體的差異(如正常人和病人)和人工分離提取的差異,紅細胞和血小板污染的程度差異性非常大,因此我們經常看到分離后的PBMC樣本千差萬別(見下圖),這也大大增加了在同一條件下,簡單快速準確計數PBMC的難度和檢測PBMC活性的難度。

二、PBMC精確計數或活力分析的重要性
PBMC(外周血單個核細胞)是免疫學功能研究中最常用的細胞模型,如細胞增殖、細胞毒性、細胞因子分泌等。
如在癌癥免疫治療領域中,需從病人全血中分離出PBMC,分離的PBMC進一步擴增或進行不同的功能檢測。激活擴增后的細胞再回輸到病人體內進行細胞治療。在整個流程中,從分離到檢測,到培養,到回輸等過程,細胞濃度和細胞活力都是必須監測的參數。
密度梯度分離液是從外周血、骨髓,及臍血分離單個核細胞最常用的方法。但是不可避免的,分離后的細胞中,會有殘存的紅細胞及血小板混合在單個核細胞中。殘存的紅細胞和血小板的多少,與個體的差異,以及分離的效果相關;但是不管分離的技術多高超,經驗多豐富,都不可避免會存在紅細胞和血小板的污染。
PBMC實驗的特征
1. 隨著時間的延長,細胞質量下降;
2. 臨床試驗相關的樣品量很大;
3. 細胞樣品不純,分離之路依賴病人樣本和操作者
如何精確、快速、簡便計數PBMC以及精確分析PBMC活力,是免疫學研究以及免疫治療領域至關重要的步驟。
1. 使用血球計數板在顯微鏡下進行手工計數PBMC,即耗時耗人力,更不能達到精確計數的目的。
2. 通過明場的常規細胞計數儀同樣不能區分紅細胞,不能達到精確計數PBMC和精確活力分析的目的。
3. 迫切需要快速、簡便、精確計數PBMC的工具替代人工計數。Nexcelom公司走在了市場領先的位置,在常規明場的細胞計數儀基礎上,開發出了雙熒光細胞活力分析儀,可通過AOPI染料進行PBMC的快速精確計數和活力分析。
參考文獻
1. Preliminary Report: Evaluation of Storage Conditions and Cryococktails during Peripheral Blood Mononuclear Cell Cryopreservation", L.M. Cosentino, W. Corwin, J.M Baust, N.Diaz-Mayoral, H.Cooley, W. Shao, R. Van Buskirk, and J.G Baust, Cell Preservation Technology, Volume 5 Number 4, 2007
2. "Viability and Functional Activity of Cryopreserved Mononuclear Cells", A. Weinberg, L. Zhang, D. Brown, A. Brice, B.Polsky, M. S. Hirsch, S. Owens, and K. Lamb Clincal and Diagnostic Laboratory Immunology, July, 2000, P714-716
3. "Cell loss and recovery in umbilical cord blood processing: a comparison of postthaw and postwash samples", V. Laroche, D. H. McKenna, G. Moroff, T. Schierman, D. Kadidlo, and J. McCullough, Transfusion, Vol., 45, Dec. 2005.
4. "Viability and Recovery of Peripheral Blood Mononuclear Cells Cryopreserved for up to 12 Years in a Multicenter Study", C. A. Kleeberger, R. H. Lyles, J. B. Margolick, C. R. Rinaldo, J. P. Phair, and J. V. Giorgi, Clinccal and Diagnostic laboratory Immunology, Vol. 6, No. 1, Jan. 1999.
三、如何精確計數PBMC和活力分析檢測
通過AOPI染料進行雙熒光計數和活力分析,是可以排除紅細胞、血小板、細胞碎片等污染的精確計數方法。
AO(吖啶橙)和PI(碘化丙啶)是可對DNA染色的細胞核染色試劑。其中AO可以通過完整的細胞膜,嵌入所有細胞(活細胞和死細胞)的細胞核,呈現綠色熒光;PI只能通過不完整的細胞膜,即死細胞的細胞膜,嵌入所有死細胞的細胞核,呈現紅色熒光。
活死單個核細胞可呈現熒光信號。而成熟的紅細胞及血小板,因為沒有細胞核,不能被AO/PI染色,因此可以完全被排除在外不被計數。

通過AOPI染料進行雙熒光計數和活力分析,可以精確計數分離后的PBMC以及活力分析,亦可進行全血中的PBMC。
分離液后樣本PBMC計數&活性分析舉例 全血樣本PBMC計數細胞及活性分析舉例


明場圖像顯示RBC/血小板污染 明場圖像根本無法計數
雙熒光活力分析儀結果報告輸出 雙熒光活力分析儀結果報告輸出


四、Cellometer細胞計數和活力分析儀器型號選擇
1. 雙熒光計數和活力分析是PBMC計數的最佳選擇方法。
三款儀器型號可選:AUTO2000/K2/ VISION CBA,可精確、快速、簡便進行PBMC計數和活力分析。



AUTO2000雙熒光細胞活力分析儀 K2雙熒光細胞分析儀 VISION CBA細胞功能分析系統
觸屏操控 電腦操控 電腦操控,高配置,可分析凋亡&細胞周期等
2. 明場的自動細胞計數儀進行PBMC計數,可通過臺盼藍排斥法進行PBMC的活力檢測。
雖然也能達到自動、快速的目的,但是仍無法有效的排除紅細胞的干擾,達到精確計數的目的。
臺盼藍排斥法檢測細胞死活,是通過臺盼藍這個細胞活性染料,其不能透過活細胞正常完整的細胞膜,故活細胞不著色,但死亡細胞的細胞膜通透性增加,可使染料通過細胞膜進入細胞內,使死細胞著色呈藍色。是最常用的檢測細胞活率的方法。
但是臺盼藍排斥法并不能精確計數活死細胞,原因是細胞膜通透性不一樣,進入細胞內的染料差異也很大,所以經常會出現很難判定是死細胞還是活細胞。
如果對PBMC計數的準確性要求不是很高,但是需要快速、自動計數,而且對實驗的一致性和重復性的要求高,可選擇以下三款計數儀:AUTO1000/MINI/AUTO T4。



MINI自動細胞計數儀 AUTO1000一體式細胞計數儀 AUTO T4自動細胞計數儀
電腦操控,小巧美觀,性價比高 一體化設計,觸屏操控 經典款,符合GLP/GMP
參考文獻
1. Chan, L.L., Wilkinson, A.R., Paradis, B.D. and Lai, N. (2012b) Rapid Image-based Cytometry for Comparison of Fluorescent Viability Staining Methods. Journal of Fluorescence 22, 1301-1311.
2. Almeida, C.-A.M., Roberts, S.G., Laird, R., McKinnon, E., Ahmed, I., Pfafferott, K., Turley, J., Keane, N.M., Lucas, A., Rushton, B., Chopra, A., Mallal, S. and John, M. (2009) Automation of the ELISpot assay for high-throughput detection of antigen-specific T-cell responses. Journal of Immunological Methods 344, 1-5.
3. Constantino, B.T. and Cogionis, B. (2000) Nucleated RBCs - Significance in the Peripheral Blood Film. Laboratory Medicine 31, 223-229.
4. Laroche, V., McKenna, D.H., Moroff, G., Schierman, T., Kadidlo, D. and McCullough, J. (2005) Cell loss and recovery in umbilical cord blood processing: a comparison of postthaw and postwash samples. Transfusion 45, 1909-1916.
5. Sigfusson, A. and Souhami, R. (1984) The Effects of Erythrocyte Contamination on Pokeweed Mitogen Induced Immunoglobulin-Synthesis in Man. Journal of Immunological Methods 72, 167-170.
6. Szabo, S.E., Monroe, S.L., Fiorino, S., Bitzan, J. and Loper, K. (2004) Evaluation of an Automated Instrument for Viability and Concentration Measurements of Cryopreserved Hematopoietic Cells. Laboratory Hematology 10, 109-111.
五、使用儀器發表文章
Author |
Date |
Title |
Journal |
Cell Type |
Cellometer / Applications |
Mahato, Ram I |
November 2013 |
Synthesis and Characterization of an Anti-Apoptotic Immunosuppressive Compound for Improving the Outcome of Islet Transplantation |
Bioconjugate Chemistry |
PBMC |
Cellometer Auto T4... Cell Counting |
Banerjee, Subhadra |
October 2013 |
Expression of the B-Cell Receptor Component CD79a on Immature Myeloid Cells Contributes to Their Tumor Promoting Effects |
PLOS ONE |
PBMC |
Cellometer (Not Specified)... Cell Concentration |
Bogoslovsky, Tanya |
September 2013 |
Cryopreservation and Enumeration of Human Endothelial Progenitor and Endothelial Cells for Clinical Trials |
Blood Disorders and Transfusion |
PBMC |
Cellometer Auto T4... Trypan Blue Exclusion |
Singh, Harjeet |
May 2013 |
Manufacture of Clincal-Grade CD-19-Specific T Cells Stably Expressing Chimeric Antigen Receptor Using Sleeping Beauty System and Artifical Antigen Presenting Cells |
PLoS one |
PBMC, Daudi, NALM-6, EL-4 |
Cellometer Unspecfied... Trypan blue viability |
Shankar Pandey, Gouri |
January 2013 |
Detection of Intracellular Factor VIII Protein in Peripheral Blood Mononuclear Cells by Flow Cytometry |
BioMed Research International |
PBMCs |
Cellometer Unspecfied... Trypan blue viability |
Filbert, Helene |
October 2012 |
Serum-free freezing media support high cell quality and excellent ELISPOT assay performance across a wide variety of different assay protocols |
Cancer Immunology and Immunotherapy |
PBMC |
Nexcelom Cellometer... Trypan blue viability |
Duran, M.C. |
July 2012 |
Enhanced protocol for CD14+ cell enrichment from equine peripheral blood via anti-human CD14 mAb and automated magnetic activated cell sorting |
Equine Veterinary Journal |
PBMCs |
Cellometer Auto T4... Trypan blue viability |
O'Connor, Colleen M. |
February 2012 |
Adoptive T-cell therapy improves treatment of canine non-Hodgkin lymphoma post chemotherapy |
Scientific Reports |
T-cells and PBMC |
Cellometer Auto T4... Trypan blue viability |
Clark, Eva H. |
January 2012 |
Plasmodium falciparum Malaria in the Peruvian Amazon, a Region of low Transmission, Is Associated with Immunologic Memory |
Infection and Immunity |
PBMC |
Cellometer Auto T4... Trypan blue viability |
Sethu, Palaniappan |
December 2011 |
Clinical application of microfluidic leukocyte enrichment protocol in mild phenotype sickle cell disease (SCD) |
Biomedical Microdevices |
Leukocyte-enriched sample, PBMC |
Cellometer (Not Specified)... Cell Number |
Uhl, Elizabeth |
August 2011 |
Identification of Altered MicroRNA Expression in Canine Lymphoid Cell Lines and Cases of B- and T-Cell Lymphomas |
Genes, Chromosomes, & Cancer |
GL-1; CL-1, LN, PBMC |
Cellometer Auto T4... Other |
Lee, Moo-Seung |
June 2011 |
Shiga toxins induce autophagy leading to differential signalling pathways in toxin-sensitive and toxin resistant human cells |
Cellular Microbiology |
Primary PBMCs, THP-1 |
Cellometer Automated Cell counter... Other |
Zierold, Claudia |
May 2011 |
Developing mechanistic insights into cardiovascular cell therapy: Cardiovascular Cell Therapy Research Network Biorepository Core Laboratory rationale |
American Heart Journal |
Bone Marrow, PBMC |
Cellometer Auto T4... Trypan blue viability |
Pathak, Shresh |
February 2011 |
IL-1B; Is Overexpressed and Aberrantly Regulated in Corticosteroid Nonresponders with Autoimmune Inner Ear Disease |
The Journal of Immunology |
PBMC |
Cellometer Auto T4... Trypan blue viability |
Wullner, Danika |
June 2010 |
Considerations for optimization and validation of an in vitro PBMC derived T cell assay for immunogenicity prediction of biotherapeutics |
Clinical Immunology |
PBMC, Dendritic, CD4 |
Cellometer Auto T4... Trypan blue viability |
Bruchova, Hana |
March 2009 |
Erythropoiesis in polycythemia vera is hyper-proliferative and has accelerated maturation |
Blood Cells, Molecules, and Diseases |
PBMC |
Cellometer Auto T4... Trypan blue viability |
Meyers, John A. |
February 2009 |
Chronic Lymphocytic Leukemia and B and T Cells Differ in their Response to Cyclic Nucleotide Phosphodiesterase Inhibitors |
The Journal of Immunology |
CLL cells, PBMC |
Cellometer Auto T4/M10... Normalizati |
White, William N. |
December 2008 |
Clinical application of microfluidic leukocyte enrichment protocol in mild phenotype sick cell disease (SCD) |
Biomedical Microdevices |
PBMC, PNM, Erythrocytes |
Cellometer Auto T4... Other |
Bruchova, Hana |
August 2007 |
Regulated expression of microRNAs in normal and polycythemia vera erythropoiesis |
Experimental Hematology |
PBMC, JAK2 V617F |
Cellometer Auto T4... Trypan blue viability |