Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
Tujuan Sel punca yang diisolasi dari darah tali pusat diketahui merupakan populasi sel mononuklear yang terdapat dalam darah tali pusat. Hingga saat ini, telah banyak laporan mengenai penggunaan sel tipe ini sebagai alternatif transplantasi sel punca secara alogenik. Berdasarkan laporan beberapa hasil studi klinis, sel darah tali pusat dapat ditoleransi sekalipun pada kasus ketidakcocokan human leukocyte antigen (HLA) pada beberapa alel dengan jumlah kasus graft versus host reaction yang rendah. Penelitian ini mengkarakterisasi profil imunogenisitas sel mononuklear darah tali pusat yang diketahui banyak mengandung sel punca, melalui analisis reaksi alogenik yang ditimbulkannya dan dibandingkan dengan reaksi terhadap sel yang berasal dari darah tepi. Metode Aloreaktifitas dari darah tali pusat dianalisis dengan pemeriksaan mixed lymphocyte reaction (MLR) dilanjutkan dengan deteksi IFN-γ yang disekresikan ke dalam medium. Tipe HLA sel donor dan efektor diperiksa dengan pemeriksaan HLA berbasis PCR untuk menentukan reaktivitas alogenik. Lebih lanjut, tingkat ekspresi HLA kelas I dan II ditentukan dengan teknik flowcytometry menggunakan antibodi monoklonal terhadap kedua molekul tersebut. Hasil Dalam medium kultur MLR dengan sel darah tali pusat, ditemukan bahwa titer IFN-γ yang terdeteksi jauh lebih rendah daripada hasil MLR sel darah tepi. Hal ini menunjukan bahwa stimulasi alogenik yang ditimbulkan oleh sel darah tali pusat lebih rendah daripada darah tepi, sekaligus mengindikasikan rendahnya potensi rejeksi tipe sel tersebut. Hasil pemeriksaan tipe HLA menunjukkan bahwa hanya terdapat 1-3 kecocokan alel dari 8 alel pasangan sel yang digunakan dalam esai MLR. Lebih lanjut, ditemukan bahwa ekspresi molekul HLA kelas I pada sel darah tali pusat sangat rendah dan hanya sebagian kecil sel yang mengekspresikan HLA kelas II. Kesimpulan Studi ini mendemonstrasikan rendahnya imunogenisitas sel darah tali pusat melalui rendahnya IFN-γ yang disekresikan pada pemeriksaan MLR dan juga melalui rendahnya ekspresi molekul HLA kelas I serta lebih sedikitnya sel yang mengekspresikan HLA kelas II pada UCBMC. Hasil penelitian ini diharapkan akan menambah pemahaman mengenai pemanfaatan darah tali pusat sebagai sumber alternatif sel punca pada transplantasi alogenik.

---

Abstract
Aim Umbilical cord blood mononucleated (UCBMC) cells has been shown to be the stem cells originated from umbilical cord blood. To date, UCBMC has been introduced as an alternative source for stem cells used in autologous and allogeneic transplantations. Several clinical studies have demonstrated that UCBMCs required less stringent selection for HLA matches between donor and recipient with less cases of graft versus host reaction. In this study, UCBMCs are known to contain many stem cells, were characterized and compared to peripheral blood for their immunogenic profile. Method To elucidate the potential of UCBMC alloreactivity, mixed lymphocyte reaction (MLR) assay was performed. The donor and effectors cells were HLA-typed using PCR method to determine their alloreactivity. Further, to distinguish the level of HLA class I and II expression flowcytometry was done using monoclonal antibodies against those molecules. All the analyse were carried out on UCBMCs and peripheral blood mononucleated cells (PBMCs). Results The result of MLR assay showed that there was less IFN-γ secretion detected in the co-cultured medium in the presence of UCBMCs compared to PBMCs counterpart, indicating less possible rejection of UCBMC. Further, we found that there were only 1-3 alleles of HLA match (out of 8 alleles) among the PBMCs and UCBMCs. By using flowcytometry assay, we could further demonstrate lower HLA Class I expression level with less amount of HLA Class II expressing cells in UCBMC compared to those in PBMCs. Conclusion These findings clearly demonstrate the low immunogenicity of UCBMCs, based on the low level of secreted IFN-γ in the MLR assay, low expression level of HLA Class I, and small population of HLA Class II expressing cells. The outcomes from this study would raise a better understanding in the usage of umbilical cord blood as an alternative source of stem cells for allogeneic transplantation. Key words: umbilical cord blood, immunogenicity, stem cell.

Abstrak :
Penggunaan antibodi poliklonal dalam sis tern pondeteksi antigen P24 HIV- 1 layak untuk dipertimbangkan mengingat variasi susunan epitop P24 pada berbagai subtipe HIV -I berpotensi mengaldbatksn kegagalan pengenalan epitop oleh antibndi monoklonal. Antibodi poliklonal yang dipero!eh melalui induksi dengan antigen rekombinan berpotensi bereaksi seeara non spesifik terhadap protein kontaminan yang terdapat dalam sediaan antigen rekombinan sehingga dapat berpengaruh pada spesifisitas sistem pendeteksi antigen. Pada penelitian sebelumnya diperoleh informasi mengenai reaksi non spesifik serum anti P24 HIV -I poliklonal yang dihasilkan melalui imunisasi kelinci, khnsusnya terhadap antigen E.coli dan Bovine Serum Albumin (BSA). Oleh ksrena penelitian ini, maka diteliti efek purifikssi dengan kromatografi afinitas dalam menghilangkan reaktivitas non spesifik antara serum anti P24 dengan E.coli dan BSA. Dampak ini dinilai dengan menggunakan teknik sandwich Enzyme Linked Immunoassay (ELISA). Purifikasi dilaknkan dengan menggunakan dua kolom kromatografi afinitas dengan ligan E.coli pada kolom pertama dan ligan P24 rekombinan HIV-1 pada kolom kedua CnBr -.sepharose digunakan sebagai matriks. Proses elusi menggunakan glycine HCI, pH 2,7. Eluen basil purifikasi dikonfirmasi dengan teknik SDS PAGE, western blot dan sandwich ELISA pendeteksi antigen P24 HIV -I. Pada SDS PAGE terbentuk pita an tara berat molekul 45-116 kDa yang menunjukkan pita antibodi. Pada uji western blot terdapat pita spesifik protein P24 rekombinan H!V -! dan tidak muncul pita non spesiflk terhadnp E.ooli. Sedangkan pada uji sandwich ELISA, eluen menunjukkan nilai abwrbansi yang lebih tinggi dibandingkan dengan kontrol negatif, dan terdapat penurunan nilai absorbansi dibandingkan dengan sistem laripa antibodi yang dipurifikasi. Nilai absorbansi cluen juga tidak menunjukkan hasil yang berbeda dengan kontrol negatif jika direaksikan dengan antigen E.coli. Namun reaktifitas non spesiflk e]uen dengan BSA pacta sistem sandwich ELISA tidak berbeda dengan reaktifitas serum prepuriflkasi. Pada uji western blot dan sandwich ELISA diperoleh pula informasi yang menunjukkan adanya reaksi non spesifik antara antibedi anti-kelinci yang digunakan dengan protein E.eo!L Puriflkasi antibedi dengan menggunakan metode kromatografi afmitas telah berhasil dilaknkan dengan kondisi optimal pemurnian dan telah diperoleh eluen yang mengandung antibodi terhadap P24 rekombinan HIV -1 yang tidak bereaksi dengan protein E.coli Reagensia yang digunakan dalam sistem pendeteksi berpotensi menimbulkan ikatan non spesiflk yang dapat mengganggu nilai absorbansi sehingga sebelum digunakan harus dinilai kelayakannya untuk digunakan dalam sistem diagnostik tertentu.

---

Polyclonal antibody may be important to be considered in sandwich ELISA which detected HIV-1 P24 due tO the existing variations in P24 epitope structure. Variations in epitope structure has the potential to produce false negative result in serologic diagnostic system that utilize monoclonal antibody. Polyclonal antibody induced by recombinant antigen could exhibit non specific reaction due to the presence of coniaminanl in antigen preparation that originates from the host used for expression of the recombinant antigen. In the previous research, we have already known that our polycional antibody in P24 H!V recombinant immunized rabbit serum had non specific reaction with E. coli protein and Bovine Serum Albumin (BSA) in sandwich ELISA system for detecting HIV-1 P24 recombinant protein. This was the ma}or reason to purifY the antibody with affinity chromatography. Our goal war to reduce the non specific reaction. We used sandwich Enzyme Linked Immunoassay (ELISA) to see the effect of purification. We used two columns affinity chromatography with different ligand in each column and CnBr sepharose as solid support. The first column utilized E.coli protein as ligand and the second one used HIV-1 P24 recombinant protein. We used glycine HCI, pH 2, 7 to elute antibody from qfflnity chromatography column. Eluen from the second column was coNfirmed with SDS PAGE, western blot and sandwich ELISA. SDS PAGE followed by comassie blue staining showed specific bands between 45-116 kDa molecular weight, which were interpreted as heavy and light chain fragments of antibody. Purified antibody in the second eluen was shown to be reactive with HIV-1 P24 recombinant protein but not E. coli protein by western blot analysis. There was a decline in the absorbance when eluen was used as detection antibody in sandwich ELISA system, compared with the system that utilized pre purified antibody. We also observed there was non specific reaction between the components in sandwich ELISA for detection of H/V-1 P24 recombinant antigen, in that we found the antibody against anti- rabbit JgG which was used in sandwich ELISA system had non specific reaction with E,cali protein. We concluded that we gained optimal condition in polyclonal antibody purification to reduce non specific reaction between polyclonal antibody to HW-1 P24 recombinant antigen with E.coli protein. Reagents which used in our sandwich ELISA system potentially Caused non specific reaction so we have to consider their application.

Abstrak :
[ABSTRAK
Pendahuluan: Infeksi dengue merupakan salah satu penyakit endemik di daerah tropis dan subtropis yang disebabkan oleh virus dengue (DENV). Hingga saat ini belum ada antiviral yang efektif untuk infeksi dengue. Penyebaran dan sirkulasi serotipe DENV berfariasi di setiap lokasi geografi, hal ini menyulitkan dalam melakukan evaluasi vaksin DENV. Oleh karena itu perlu dikembangkan kandidat vaksin DENV menggunakan strain Indonesia supaya dapat memberikan proteksi maksimal. Pada peneltian ini dikembangkan kandidat vaksin DNA tetravalen DENV berbasis gen prM-E DENV strain Indonesia. Metode: Konstruksi plasmid rekombinan kandidat vaksi dilakukan dengan cara menyisipkan gen prM-E setiap serotipe DENV ke dalam vektor pUMVC4a. Gen prM-E DENV merupakan strain Indonesia, yang diamplifikasi dari serum pasien yang terinfeksi dengan virus ini. Kemampuan plasmid rekombinan mengekspresikan protein prM-E DENV diuji di sel mamalia. Kemampuan kandidat vaksin menginduksi respon imun humoral dievaluasi secara monovalen dan tetravalen di mencit jenis ddY. Titer IgG anti dengue diperiksa menggunakan teknik ELISA, sedangkan titer antibodi netralisasi di tentukan dengan uji FRNT. Proteksi vaksin terhadap mencit yang diimunisasi dievaluasi dengan melakukan uji tantang menggunakan sel K562 yang diinfeksi DENV-2. Viremi virus di tentukan dengan menggunakan teknik foccus assay. Hasil: Konstruksi plasmid rekombinan kandidat vaksin DENV-1 dan DENV-3 sudah berhasil dilakukan. Plasmid dapat mengekspresikan protein prM-E DENV di sel mamalia, namun karakteristik dan kinetik protein masih belum dapat diketahui dengan jelas. Keempat kandidat vaksin DNA yang sedang dikembangkan dapat menginduksi respon imun, baik secara monovalen maupun tetravalen. Imunisasi secara tetravalen dapat memberikan proteksi pada mencit yang diuji tantang dengan sel K562 yang diinfeksi dengan DENV-2.;

---

ABSTRACT
Introduction: Dengue infections are caused by dengue viruses (DENV) and are endemic in tropical and subtropical regions. At present, there is no effective antiviral treatment for dengue infection. Distribution and circulation of DENV serotypes varies by geographic location, it is difficult to evaluate DENV vaccine. Therefore, it is necessary to develop a vaccine candidate DENV using Indonesian strains in order to provide maximum protection. However, in this study, we constructed a recombinant plasmid-based prM-E gene from the Indonesia strain as a DENV DNA vaccine candidate. Methode: The recombinant plasmid was prepared by inserting the prM-E gene from each DENV serotypes into the plasmid backbone pUMVC4a. prM-E gene an Indonesia strain, which was amplified from patient sera infected with DENV. The ability of the recombinant plasmid expressing the prM-E DENV protein tested in mammalian cells. The ability of candidate vaccines induce humoral immune responses were evaluated monovalent and tetravalent in ddY mice. IgG titers of anti-dengue examined using ELISA technique, while neutralizing antibody titers determined with FRNT test. Vaccine protection against the immunized mice was evaluated by conducting challenge test using K562 cells infected by DENV-2. Viremia was determined by using the foccus assay. Result: Construction of recombinant plasmid vaccine candidate DENV-1 and DENV-3 was successfully performed. Plasmids can express prM-E DENV proteins in mammalian cells, but the characteristics and kinetics of protein still can not clearly known. Fourth DNA vaccine candidate that is being developed to induce an immune response, either monovalent or tetravalent. Tetravalent immunization may provide protection in mice challenged tested with K562 cells infected with DENV-2.;Introduction: Dengue infections are caused by dengue viruses (DENV) and are endemic in tropical and subtropical regions. At present, there is no effective antiviral treatment for dengue infection. Distribution and circulation of DENV serotypes varies by geographic location, it is difficult to evaluate DENV vaccine. Therefore, it is necessary to develop a vaccine candidate DENV using Indonesian strains in order to provide maximum protection. However, in this study, we constructed a recombinant plasmid-based prM-E gene from the Indonesia strain as a DENV DNA vaccine candidate. Methode: The recombinant plasmid was prepared by inserting the prM-E gene from each DENV serotypes into the plasmid backbone pUMVC4a. prM-E gene an Indonesia strain, which was amplified from patient sera infected with DENV. The ability of the recombinant plasmid expressing the prM-E DENV protein tested in mammalian cells. The ability of candidate vaccines induce humoral immune responses were evaluated monovalent and tetravalent in ddY mice. IgG titers of anti-dengue examined using ELISA technique, while neutralizing antibody titers determined with FRNT test. Vaccine protection against the immunized mice was evaluated by conducting challenge test using K562 cells infected by DENV-2. Viremia was determined by using the foccus assay. Result: Construction of recombinant plasmid vaccine candidate DENV-1 and DENV-3 was successfully performed. Plasmids can express prM-E DENV proteins in mammalian cells, but the characteristics and kinetics of protein still can not clearly known. Fourth DNA vaccine candidate that is being developed to induce an immune response, either monovalent or tetravalent. Tetravalent immunization may provide protection in mice challenged tested with K562 cells infected with DENV-2., Introduction: Dengue infections are caused by dengue viruses (DENV) and are endemic in tropical and subtropical regions. At present, there is no effective antiviral treatment for dengue infection. Distribution and circulation of DENV serotypes varies by geographic location, it is difficult to evaluate DENV vaccine. Therefore, it is necessary to develop a vaccine candidate DENV using Indonesian strains in order to provide maximum protection. However, in this study, we constructed a recombinant plasmid-based prM-E gene from the Indonesia strain as a DENV DNA vaccine candidate. Methode: The recombinant plasmid was prepared by inserting the prM-E gene from each DENV serotypes into the plasmid backbone pUMVC4a. prM-E gene an Indonesia strain, which was amplified from patient sera infected with DENV. The ability of the recombinant plasmid expressing the prM-E DENV protein tested in mammalian cells. The ability of candidate vaccines induce humoral immune responses were evaluated monovalent and tetravalent in ddY mice. IgG titers of anti-dengue examined using ELISA technique, while neutralizing antibody titers determined with FRNT test. Vaccine protection against the immunized mice was evaluated by conducting challenge test using K562 cells infected by DENV-2. Viremia was determined by using the foccus assay. Result: Construction of recombinant plasmid vaccine candidate DENV-1 and DENV-3 was successfully performed. Plasmids can express prM-E DENV proteins in mammalian cells, but the characteristics and kinetics of protein still can not clearly known. Fourth DNA vaccine candidate that is being developed to induce an immune response, either monovalent or tetravalent. Tetravalent immunization may provide protection in mice challenged tested with K562 cells infected with DENV-2.]

Abstrak :
The book will introduce the different technological advances that led to this breakthrough. In addition, several examples will be provided of nucleotide variants in noncoding sequences that have been shown to be associated with various human diseases.