Terapia com células CAR-T: reprogramação celular para o combate de neoplasias malignas / CAR-T cell therapy: cell reprogramming to combat malignant neoplasms

As células CAR-T são linfócitos geneticamente modificados para reconhecerem um espectro amplo de antígenos de superfície celulares. Além disso, atacam células tumorais malignas, que expressam esses antígenos, por meio da ativação da coestimulação citoplasmática, secreção de citocinas, citólise de células tumorais e proliferação de células T. O objetivo desse estudo é abordar a imunoterapia com células CAR-T, a fim de explicar seu conceito, processo de fabricação e papel no tratamento de neoplasias hematológicas e tumores sólidos. Foi realizada uma revisão através do portal PubMed, utilizando como descritores: "car-t cell therapy" e "neoplasms", determinados com base nos "Descritores em Ciências da Saúde". Foram obtidos, inicialmente, 10 artigos, os quais foram lidos integralmente para a confecção dessa revisão. Além disso, foram adicionados 3 ensaios clínicos atualizados sobre o tema. Na terapia com células CAR-T, as células T são coletadas do paciente, geneticamente modificadas para incluir receptores de antígeno específicos e, posteriormente, expandidas em laboratórios e transfundidas de volta para o paciente. Assim, esses receptores podem reconhecer células tumorais que expressam um antígeno associado a um tumor. A terapia com células CAR-T é mais conhecida por seu papel no tratamento de malignidades hematológicas de células B, sendo a proteína CD19 o alvo antigênico mais bem estudado até o momento. Entretanto, estudos estão sendo feitos para verificar a eficácia desse tratamento, também, em tumores sólidos. Portanto, apesar de inicialmente ser indicada apenas para um grupo seleto de pessoas, essa terapia tem demonstrado grande potencial para atuar em um espectro maior de pacientes.

The CAR-T cells are lymphocytes genetically modified to recognize a broader spectrum of cell surface antigens. In addition, they attack malignant tumor cells, which express these antigens, by activating cytoplasmic co-stimulation, cytokine secretion, tumor cell cytolysis and T cell proliferation. The aim of this study is to address immunotherapy with CAR-T cells, in order to explain its concept, manufacturing process and role in the treatment of hematological neoplasms and solid tumors. This is a literature review conducted through the PubMed portal, that uses the terms "car-t cell therapy" and "neoplasms" as descriptors, determined based on the DeCS (Descritores em Ciências da Saúde). To prepare this review, initially 10 articles were found and read in full. In addition, 3 updated clinical trials on the subject were added. For CAR-T cell therapy, T cells are collected from the patient, genetically modified to include specific antigen receptors, and later expanded in laboratories and transfused back to the patient. Thus, these receptors can recognize tumor cells that express a tumor-associated antigen. CAR-T cell therapy is best known for its role in the treatment of B cell hematological malignancies, with the CD19 protein being the most studied antigenic target to date. However, studies are being conducted to verify the effectiveness of this treatment, also, in solid tumors. Therefore, despite being formulated only for a selected group of patients, this therapy has great potential to act on a broader spectrum of patients.

Chimeric Antigen Receptor T Cell Therapy: A Novel Modality for Immune Modulation / 전남의대학술지

Cancer remains a leading cause of death, despite multimodal treatment approaches. Even in patients with a healthy immune response, cancer cells can escape the immune system during tumorigenesis. Cancer cells incapacitate the normal cell-mediated immune system by expressing immune modulation ligands such as programmed death (PD) ligand 1, the B7 molecule, or secreting activators of immune modulators. Chimeric antigen receptor (CAR) T cells were originally designed to target cancer cells. Engineered approaches allow CAR T cells, which possess a simplified yet specific receptor, to be easily activated in limited situations. CAR T cell treatment is a derivative of the antigen-antibody reaction and can be applied to various diseases. In this review, the current successes of CAR T cells in cancer treatment and the therapeutic potential of CAR T cells are discussed.

Progress in shark single-domain antibody / 生物工程学报

Monoclonal antibody (mAb) is an important biological macromolecule and widely used in immune detection, in vitro diagnostics, and drug discovery. However, the inherent properties of mAb restrict its further development, such as high molecular weight and complex structure. Therefore, there is an urgent need to develop alternatives for mAb. Various types of miniaturized antibodies have been developed, among which the variable domain of immunoglobulin new antigen receptor (VNAR) is very attractive. The shark single-domain antibody, also known as shark VNAR, is an antigen-binding domain obtained by genetic engineering technology based on the immunoglobulin new antigen receptor (IgNAR) that naturally exists in selachimorpha. It has a molecular weight of 12 kDa, which is the smallest antigen-binding domain found in the known vertebrates at present. Compared with mAb, the shark VNAR exhibits various superiorities, such as low molecular weight, high affinity, tolerance to the harsh environment, good water solubility, strong tissue penetration, and recognition of the hidden epitopes. It has attracted wide attention in the fields of immunochemical reagents and drug discovery. In this review, various aspects of shark VNAR are elaborated, including the structural and functional characteristics, generating and humanization techniques, affinity maturation strategies, application fields, advantages and disadvantages, and prospects.

A general view of CD33⁺ leukemic stem cells and CAR-T cells as interesting targets in acute myeloblatsic leukemia therapy

Acute myeloblastic leukemia (AML) is the most frequent acute leukemia in adulthood with very poor overall survival rates. In the past few decades, significant progresses had led to the findings of new therapeutic approaches and the better understanding of the molecular complexity of this hematologic malignancy. Leukemic stem cells (LSCs) play a key role in the initiation, progression, regression, and drug resistance of different types of leukemia. The cellular and molecular characteristics of LSCs and their mechanism in the development of leukemia had not yet been specified. Therefore, determining their cellular and molecular characteristics and creating new approaches for targeted therapy of LSCs is crucial for the future of leukemia research. For this reason, the recognition of surface maker targets on the cell surface of LSCs has attracted much attention. CD33 has been detected on blasts in most AML patients, making them an interesting target for AML therapy. Genetic engineering of T cells with chimeric antigen receptor (CAR-T cell therapy) is a novel therapeutic strategy. It extends the range of antigens available for use in adoptive T-cell immunotherapy. This review will focus on CAR-T cell approaches as well as monoclonal antibody (mAB)-based therapy, the two antibody-based therapies utilized in AML treatment.

Chimeric Antigen Receptor T-Cell Therapy for Diffuse Large B-Cell Lymphoma / 대한내과학회지

CD19 chimeric antigen receptor T-cell (CAR-T) therapy, a genetically engineered cell therapy, showed unprecedented efficacy in the treatment of relapsed or refractory diffuse large B-cell lymphoma. Two agents, axicabtagene ciloleucel and tisagenlecleucel, were approved by the Food and Drug Administration in 2017. However, CAR-T therapy is a treatment with complex logistics and high costs, as well as inherent adverse events, including cytokine-release syndrome and neurotoxicity. In addition, predictive biomarkers for efficacy and toxicity are lacking. Industry-academy cooperation is urgently required to develop CAR-T therapy that is effective, safe, and affordable for patients in Korea.

Delayed Terminal Ileal Perforation in a Relapsed/Refractory B-Cell Lymphoma Patient with Rapid Remission Following Chimeric Antigen Receptor T-Cell Therapy / Journal of the Korean Cancer Association, 대한암학회지

Chimeric antigen receptor T-cell strategy targeting CD19 (CART19) has prominent anti-tumor effect for relapsed/refractory B-cell lymphomas. CART19-associated complications have been gradually recognized, however, late-onset complications have not been extensively studied. Herein, for the first time we report a diffuse large B-cell lymphoma patient with terminal ileum involvement obtained rapid remission and developed spontaneous terminal ileal perforation 38 days following CART19 infusion. The late-onset perforation reminds us that, for the safety of CART treatment, more cautions are warranted for the management of delayed GI complications.

Application of Chimeric Antigen Receptor-Modified NK Cells in Multiple Myeloma / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the killing effect of CAR (CD138-CD28-CD3ζ)-NK cells on myeloma cells through construction of CAR(CD138-CD28-CD3)-NK cells.</p><p><b>METHODS</b>The antiCD138scFv-CD28-CD3 zeta plasmid pcDNA3.1 was constructed, which then together with 3 plasmid lentiviral packaging system were transfected into 293T cells, the virus was collected. Furthermore, in order to get the stably transfected cell line, the NK92MI cell line was infected by the virus, then the positive cells were screened by puromycin. The expression of the CARNK cells were verified by RT-PCR and Western blot. At last the ability of secreting cytokine CD107a was detected by flow cytometry, and the statistical analysis was carried out to verify the anti-myeloma effect of CAR-NK cells.</p><p><b>RESULTS</b>Gene fragment of the CAR(antiCD138scFv-CD28-CD3ζ) was constructed successfully by gene engineering technique in vitro, and the gene sequence was verified to be correct by sequencing. By virus packaging technology, the virus expressing the protein of the CAR was obtained. PCR and Western blot verified the expression of CAR fusion protein on the sufurce of NK cells. The cell killing experiment confirmed that the CAR-NK cells possessed the ability to secrete cytokine CD107a superior to control cells and showed the obvious killing effect on multiple myeloma cells.</p><p><b>CONCLUSION</b>The CAR can be constructed in vitro, and express on NK92 cells. The CAR-NK cells can kill the multiple myeloma cells expressing CD138 antigen, thereby plays an antimyeloma effect.</p>

Applicability of PCR-based clonality assay in dogs with multicentric lymphoma / Aplicabilidade do ensaio de clonalidade por PCR em cães com linfoma multicêntrico

Linfoma multicêntrico apresenta alta prevalência dentre as neoplasias em cães, e o diagnóstico rotineiro não é eficaz para avaliação de prognóstico. A PCR para rearranjos de receptores de antígeno (PRRA) apresenta potencial para classificação e estadiamento de linfomas. Este trabalho objetiva relatar o desenvolvimento de um protocolo de PRRA para aplicação em cães, baseando-se em condições e primers descritos na literatura. Foram coletados aspirados de linfonodo de 10 cães com linfoma multicêntrico e 15 lâminas de linfonodo positivas para linfoma já secas ao ar, fixadas e coradas. O protocolo utilizado demonstrou-se eficaz na amplificação de DNA das amostras frescas e das lâminas, com sensibilidade de 75%, similar à de estudos anteriores. Resultados parciais sugerem prevalência de linfomas de células B (60%) sobre células T (40%). O presente estudo abre precedentes para uma série de novos estudos com diagnóstico molecular de linfomas.(AU)

Diagnosis of Lymphoid Malignancy by PCR for Analysis of Antigen Receptor Rearrangement after Blood Transfusion in a Dog with Acute Lymphocytic Leukemia

Acute lymphocytic leukemia (ALL) is uncommon lymphoid malignancy in dogs, and its diagnosis is challenging. A 14-year-old spayed female mixed breed dog was transferred to a veterinary medical teaching hospital for an immediate blood transfusion. The dog showed lethargy, pale mucous membranes, and a weak femoral pulse. Complete blood count revealed non-regenerative anemia and severe leukopenia with thrombocytopenia. ALL was tentatively diagnosed based on the predominance of immature lymphoblasts on blood film examination. For confirmation of lymphoid malignancy, PCR for antigen receptor rearrangement (PARR) on a peripheral blood sample and flow cytometry analysis were performed after blood transfusion. Flow cytometry analysis revealed that lymphocyte subsets were of normal composition, but PARR detected a T-cell malignancy. The dog was diagnosed with ALL and survived 1 wk after diagnosis. In conclusion, after blood transfusion, flow cytometry was not a reliable diagnostic method for an ALL dog, whereas PARR could detect lymphoid malignancy. Our results suggest that PARR should be the first-line diagnostic tool to detect canine lymphoid malignancy after a blood transfusion.

Application of Chimeric Antigen Receptor-Modified CAR-T/NK Cells to Treatment of Multiple Myeloma / 中国实验血液学杂志

Chimeric antigen receptor(CAR) is a synthesized transmembrane protein, which redirects the modified cells through specific or associated antigen on tumor cells. CAR-modified T/NK cells, especially CAR-T cells, are a new tool of rapidly developing of adoptive immunotherapy of tumor in recent years, they give T/NK cells the targeting cytotoxic activity and can overcome the tumor immunosuppressive microenvironment and break the state of the host immune tolerance. CAR combines the single-chain antibody to tumor-associated antigen with T/NK cells' activated motifs, giving T/NK cells' tumor targeting activity, so enhancing their cytotoxic activity and lasting the vitality by gene transduction. In this article the CAR development, comparison of CAR-T and CAR-NK cells, surface markers on MM cells and use of CAR in MM, and CAR perspectives are summarized.

Cloning of VH and VL Gene of Human anti-IL1RAP McAb and Construction of Recombinant Chimeric Receptor / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To clone the variable region genes of human anti-IL1RAP (IL-1 receptor accessory protein) monoclonal antibodies (McAb) and to construct IL1RAP chimeric antigen receptors (CARs).</p><p><b>METHODS</b>The VH and VL DNA of IL1RAP single chain antibodies were amplified by RACE and overlap extension PCR from total RNA extracted from 3H6E10 and 10D8A7 hybridoma and ligated into specific IL1RAP single-chain variable fragments (scFv). CD8α transmembrane domain, CD137 intracellular domain, TCR ζ chain, human CD8α signal peptide and scFv-anti-IL1RAP were cloned into plasmid LV-lac. Recombinant lentiviruses were generated by co-transfection of recombinant plasmid LV-lac, pMD2. G, and psPAX2 helper vectors into 293FT packing cells.</p><p><b>RESULTS</b>The VH and VL genes of 2 human anti-IL1RAP McAb were acquired. The 3H6E10 VH and VL genes consisted of 402 bp and 393 bp encoding 134 and 131 aminoacid residues, respectively; 10D8A7 VH and VL genes consisted of 423 bp and 381 bp encoding 141 and 127 amine acid residues, respectively. Recombinant expression vertors LV-3H6E10 scFv-ICD and LV-10D8A7 scFv-ICD (ICD: CD8α transmembrane domain-CD137 intracellular domain-TCR ζ chain) were constructed. The target fragments were demonstrated by sequencing analysis. Recombinant plasmids were transfected into 293FT cells and lentiviral particles were acquired.</p><p><b>CONCLUSION</b>Human anti-IL1RAP recombinant receptors are constructed successfully and lay a good foundation for the construction of IL1RAP-CAR killer T cell vaccine.</p>

The human application of gene therapy to re-program T-cell specificity using chimeric antigen receptors / 癌症

The adoptive transfer of T cells is a promising approach to treat cancers. Primary human T cells can be modified using viral and non-viral vectors to promote the specific targeting of cancer cells via the introduction of exogenous T-cell receptors (TCRs) or chimeric antigen receptors (CARs). This gene transfer displays the potential to increase the specificity and potency of the anticancer response while decreasing the systemic adverse effects that arise from conventional treatments that target both cancerous and healthy cells. This review highlights the generation of clinical-grade T cells expressing CARs for immunotherapy, the use of these cells to target B-cell malignancies and, particularly, the first clinical trials deploying the Sleeping Beauty gene transfer system, which engineers T cells to target CD19+ leukemia and non-Hodgkin's lymphoma.

Vaccine strategies utilizing C-type lectin receptors on dendritic cells in vivo

Dendritic cells (DCs) are professional antigen-presenting cells capable of initiating and regulating innate and adaptive immunity. The development of effective ways to produce a large number of DCs in laboratories made the use of DCs available in various vaccine approaches. Compared to conventional vaccines, focused on protective antibody responses, DC vaccines emphasize protective T cell immunity but might elicit strong antibody responses as well. In addition, the recent discoveries of functionally distinct DC subsets in various organs and tissues are likely to increase the potential of exploiting DCs in vaccines and immunotherapy. Vaccines composed of DCs generated ex vivo, pulsed with antigens, and matured prior to being re-infused to the body have been widely tried clinically but resulted in limited success due to various obstacles. In this review, new approaches that protein vaccines are selectively targeted to the endocytic C-type lectin receptors on surface of DCs in vivo are discussed.

Advances in immunotherapy of hematological malignancies by using chimeric antigen receptor-modified lymphocytes / 中国实验血液学杂志

Chimeric antigen receptors (CAR) are fusion proteins between single-chain variable fragments (scFv) from monoclonal antibodies and signaling domains of T-cells, which allow T-cells recognize specific cell-surface targets in an MHC-unrestricted fashion. The structure of CAR has changed over time, from first generation CAR (scFv + signaling moiety) to 2 and 3 generation CAR (combined with one or multiple costimulatory endodomains, such as CD28, 4-1BB and OX40), which enhance persistence, expansion and cytotoxicity of CAR. Many clinical trials treating hematological malignancies using the CAR-modified T-cells targeting CD19 and CD20 are under evaluation or even finished. These clinical trials indicated that CAR-based immunotherapy prolonged the survival of patients with relapsed/refractory B-cell malignancies. Furthermore, CAR have being studied to translate to other fields like adoptive therapy after hematopoietic stem cell transplantation. As to the treatment toxicity, CAR modified T-cell infusion is tolerant and safe in most patients. However, insertional mutagenesis, off-target effect and inflammatory response are safety issues surrounding CAR-modified T-cell therapy. In this review, the use of CAR technique in treatment of hematologic malignancies and evaluation of CAR safety are summarized.

Advances in the study of natural small molecular antibody / 药学学报

Small molecule antibodies are naturally existed and well functioned but not structurally related to the conventional antibodies. They are only composed of heavy protein chains or light chains, much smaller than common antibody. The first small molecule antibody, called Nanobody was engineered from heavy-chain antibodies found in camelids. Cartilaginous fishes also have heavy-chain antibodies (IgNAR, "immunoglobulin new antigen receptor"), from which single-domain antibodies called Vnar fragments can be obtained. In addition, free light chain (FLC) antibodies in human bodies are being developed as therapeutic and diagnostic agents. Comparing to intact antibodies, common advantages of small molecule antibodies are with better solubility, tissue penetration, stability towards heat and enzymes, and comparatively low production costs. This article reviews the structural characteristics and mechanism of action of the Nanobody, IgNAR and FLC.

Study of dual rearrangements of lymphocytic antigen receptor genes in non-Hodgkin lymphoma / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the rate of dual rearrangements of lymphocytic antigen receptor genes in non-Hodgkin lymphomas (NHL) and its pathogenesis and pathologic significance.</p><p><b>METHODS</b>PCR analysis of monoclonal, polyclonal and dual rearrangements of IgH and TCR gamma, TCR beta genes was carried out in 125 cases of NHL to evaluate the rate of dual rearrangements, immunohistochemistry was performed for a Ki67 protein expression in 117 cases and the proliferation index was calculated. The relationship between antigen receptor gene rearrangements and proliferation index was analyzed.</p><p><b>RESULTS</b>Combination of the two pairs of IgH gene primers with the multiplex PCR for TCR gamma and TCR beta gene revealed dual rearrangements in 8% (8/96) of B-NHL, 17% (5/29) of T-NHL. In B cell NHL, IgH gene monoclonal, dural and polyclonal rearrangements were identified in 65, 8 and 15 cases respectively, while in T-cell NHL, they were in 15, 5 and 9 cases, respectively. There was no significant difference between proliferation index and monoclonal, dual, polyclonal rearrangements in both B-NHL and T-NHL by One-way test.</p><p><b>CONCLUSION</b>Dual rearrangements in NHL are not rare and have no relationship with proliferation index.</p>

WEHI-231 cells are defective in the ligand-induced internalization of B cell antigen receptor

No abstract available.

Diagnostic Usefulness and Limitation of Fine Needle Aspiration Cytology of Lymph Node: Analysis of 176 Cases Confirmed by Biopsy / 대한세포병리학회지

The accuracy of fine needle aspiration cytology(FNAC) of the lymph node was investigated through a review of 176 FNAC cases and the corresponding biopsies. We chose 157 FNAC cases after the exclusion of 19 inadequate ones. Sensitivity of malignancy was 94.0%, specificity 100%, false negativity 6.0%, and false positivity 0.0%. The overall diagnostic accuracy was 96.8%. Sensitivity of metastatic carcinoma was 98.0% and that of malignant lymphoma was 87.9%. False negative cases included one metastatic carcinoma and four malignant lymphomas. The aspirates of metastatic carcinoma with false negativity exhibited a diffuse smear of keratin debris without viable cells, which led to the difficulty in differentiation from benign epithelial cyst. The cases of malignant lymphoma with false negative diagnosis were two Hodgkin diseases, one Lennert's lymphoma, and one peripheral T cell lymphoma in the histologic sections. On the analysis of 39 cases of tuberculosis, 17 cases(43.6%) were diagnosed as tuberculosis, 4(10.3%) as granulomatous lymphadenitis, 3(7.7%) as necrotizing lymphadenitis, and 15(38.5%) as reactive hyperplasia or pyogenic inflammation. Sensitivity of tuberculosis was 53.9%. In conclusion, lymph node FNAC is an excellent non-invasive diagnostic tool for the diagnosis of metastatic carcinoma. The diagnostic accuracy of malignant lymphoma could be improved with flow cytometry or polymerase chain reaction for antigen receptor genes. For the FNAC diagnosis of tuberculosis, AFB stain, culture, and PCR would be helpful as adjuvant techniques.

Two Cases of Familial Juvenile Hyperuricemic Nephropathy

The accuracy of fine needle aspiration cytology (FNAC) of the lymph node was investigated through a review of 176 FNAC cases and the corresponding biopsies. We chose 157 FNAC cases after the exclusion of 19 inadequate ones. Sensitivity of malignancy was 94.0%, specificity 100%, false negativity 6.0%, and false positivity 0.0%. The overall diagnostic accuracy was 96.8%. Sensitivity of metastatic carcinoma was 98.0% and that of malignant lymphoma was 87.9%. False negative cases included one metastatic carcinoma and four malignant lymphomas. The aspirates of metastatic carcinoma with false negativity exhibited a diffuse smear of keratin debris without viable cells, which led to the difficulty in differentiation from benign epithelial cyst. The cases of malignant lymphoma with false negative diagnosis were two Hodgkin diseases, one Lennert's lymphoma, and one peripheral T cell lymphoma in the histologic sections. On the analysis of 39 cases of tuberculosis, 17 cases (43.6%) were diagnosed as tuberculosis, 4 (10.3%) as granulomatous lymphadenitis, 3 (7.7%) as necrotizing lymphadenitis, and 15 (38.5%) as reactive hyperplasia or pyogenic inflammation. Sensitivity of tuberculosis was 53.9%. In conclusion, lymph node FNAC is an excellent non-invasive diagnostic tool for the diagnosis of metastatic carcinoma. The diagnostic accuracy of malignant lymphoma could be improved with flow cytometry or polymerase chain reaction for antigen receptor genes. For the FNAC diagnosis of tuberculosis, AFB stain, culture, and PCR would be helpful as adjuvant techniques.