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Selain dari embrio, sumsum tulang dan darah tali pusat, sel punca dapat diisolasi dari jaringan lemak. Liposuction menghasilkan limbah lemak yang dapat diujicobakan menjadi sumber sel punca mesenkimal. Pada penelitian ini dilakulan isolasi sel punca asal lipoaspirat dengan cara menurut Zuk dan Caroline yang dimodifikasi sesuai dengan kondisi laboratorium. Usaha isolasi memberikan hasil identitas sel punca yang sesuai dengan ketentuan sel punca menurut Dominici. Identitas sel punca ditetapkan menggunakan antibodi berfluoresensi dan dideteksi dengan alat flowcytometer. Supernatan kultur sel punca dikumpulkan dan kadar enzim Indoleamine 2,3-dioksigenase di tetapkan menggunakan metode elisa. Dari hasil didapat bahwa sel punca yang dikultur dengan keberadaan IFN gamma menghasilkan kadar IDO yang tinggi. IDO berperan dalam menyebabkan sifat supresi sel imun. Sehingga dapat dikatakan bahwa sel punca hasil isolasi dari sumber lipoaspirat menunjukkan sifat imunosupresi diliaht dari kadar IDO yang terukur.

Antioxidants possess ability to protect body from damage caused by free radical-induced oxidative stress. In order to evaluate the antioxidant activity of spice ethanol extracts of cucurmin has been used as positive control. Antioxidant activities have been determined by measuring 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activity and hydrogen peroxide (H2O2) scavenging activity of spice extracts including turmeric (Curcuma longa L. ), white saffron (Curcuma mangga Val.), temulawak (Curcuma xanthorrhiza Roxb), ginger (Zingiber officinale Roscoe). Ten concentrations of extracts 100; 50; 25; 12.5; 6.25; 3.125; 1.563; 0.781; 0.391 and 0.195 μg/mL were performed to determine the DPPH and H2O2 scavenging activities. Results showed that Inhibitory Concentrations (IC)-50 of DPPH were as followed C. longa 8.33 μg/mL; C. mangga 277.79; C. xanthorrhiza 39.58 μg/mL μg/m; Z. officinale 10.51 μg/mL; and curcumin 7.85 μg/mL. Meanwhile, the highest H2O2 scavenging activity each extract were as followed C. longa 55.82%, C. mangga 44.52%, C. xanthorrhiza 49.04%, Z. officinale 46.21 and curcumin 52.77%. In our current study, C. longa extract showed the highest antioxidant activity among all tested extracts and the lowest antioxidant activity was C. mangga. C. longa could be a potential candidate to inhibit the oxidative stress.

Keywords: DPPH, antioxidant, free radical, hydrogen peroxide, C. longa, C. mangga, C. xanthorrhiza, Z. officinale , curcumin

Within the last few years, mesenchymal stem cell (MSC) has been reported to have immunomodulator capacity towards autoimmune diseases and to prevent tissue rejection in allogenic transplantation. Many studies have shown MSC’s ability to inhibit T cell proliferation and to induce immunosuppressive microenvironment through the production of prostaglandins, and interleukin-10. Moreover, it has been reported that MSC also has a capability in reducing circulating autoantibody in autoimmune patients following MSC transfusion. So far, there has been no report stating the presence of Fc receptors (receptors for immunoglobulin) on MSCs. Therefore, the aim of this study is to know whether MSCs isolated from lipoaspirate express FcγRs by measuring transcription of mRNA of FcγRs, The MSCs was isolated from lipoaspirate, cultured in suitable medium and confirmed to be MSC according to the criteria published by International Society for Cellular Therapy. Total mRNA of MSC was isolated, and detection of human FcγR1, FcγR2a and FcγR2b mRNA was performed in a thermocycler. The result of this study showed that at the first passage of MSCs, FcγRs mRNA was detected. However the expression was no longer present after more than 4 passages. Further, increased level of FcγRs mRNA expression was detected with the addition of IFNγ in the culture.  This preliminary finding opens a new insight for the understanding of interaction between MSCs and immunoglobulin G through FcgRs.

Keywords: mesenchymal stem cell, Fcγ receptor, interferon γ, immunoglobulin G.

  Enzim indoleamin-2,3-dioksigenase (IDO) adalah enzim penting pada katabolisme triptofan dan derivat indoleamin lain. IDO memecah triptofan dan derivat indoleamin lain menjadi produk antara kinurenin. Enzim ini diekspresikan pada jaringan manusia dan hewan khususnya pada jaringan limfoid dan plasenta. Sel-sel imun seperti makrofag dan sel dendritik mengekspresikan IDO. Beberapa penelitian menyebutkan bahwa ekspresi IDO bertanggungjawab terhadap efek tolerogenik sistem imun. Penghambatan terhadap aktivitas IDO dapat berakibat meningkatnya reaktivitas respon imun. Sebaliknya peningkatan aktivitas IDO dapat meningkatkan efek tolerogenik sistem imun. Peningkatan efek tolerogenik ini dibutuhkan diantaranya untuk menunjang keberhasilan tindakan transplantasi jaringan dari donor yang berbeda. Sel punca mesenkimal adalah sel punca yang dapat diisolasi dari sumsum tulang, jaringan lemak, dan darah. Sel punca mesenkimal telah terbukti mampu mengurangi risiko terjadinya reaksi penolakan transplantasi jaringan. Pada percobaan in vitro, ditemukan  adanya sekresi IDO bila sel punca mesenkimal dikultur bersama dengan  limfosit yang berasal dari 2 donor yang berbeda. Tulisan ini membahas tentang peran IDO dalam respon imun dan hubungannya dengan efek imunosupresi dari sel punca mesenkimal.

Kata kunci : Indoleamin-2,3-dioksigenase, sel punca mesenkimal, imunosupresi

Abstract

Lipoaspirate, a wasted by product from liposuction procedure recently has been shown to contain abundant mesenchymal stem cells (MSCs). A simplified method which is suitable to be performed in a basic laboratory will facilitate development of stem cell research in developing countries.  Digesting with collagenase type I, followed by a basic filtration method and purification by cell culture could isolate MSCs which fulfill the minimum criteria according Mesenchymal and Tissue Stem Cell Committee of the International Society of Cell Therapy. The procedure was practicable to be performed within a basic laboratory. The outcomes from this study are expected to encourage the progress of stem cell research in Indonesia.