Pouneh Dokouhaki

The efficient isolation of murine splenic dendritic cells and their cytochemical features

Despite their importance in professional antigen presentation and their ubiquitous presence, dendritic cells (DCs) are usually found in such trace amounts in tissues that their isolation with high purity is a difficult task. Because of their scarcity, accurate determination of the purity of isolated dendritic cells is very important. In this study, we purified murine splenic dendritic cells by a three-step enrichment method and evaluated their morphological, cytochemical and functional characteristics. Purity of the isolated cells was determined by established methods such as flow cytometry (FC) and immunocytochemistry (ICC) using anti-CD11c monoclonal antibody. In order to test purified DC functional properties, we used in vivo antigen presentation assay. Our results showed that antigen-pulsed DCs are potent stimulators of antigen-specific lymphocyte proliferation. We studied myeloperoxidase (MPO) and non-specific esterase (NSE) activity in isolated cells to determine the purity of dendritic cells compared to more conventional methods. Our results showed that murine splenic dendritic cells were deficient in both MPO and NSE activity and the percentage of purity obtained by NSE staining on isolated cells was comparable to the results obtained by either FC or ICC. To our knowledge, this is the first report on using NSE activity for determination of the purity of isolated murine splenic dendritic cells. We, therefore, recommend that NSE activity be employed as a simple, inexpensive and yet accurate method for evaluation of the purity of isolated murine splenic dendritic cells.

Mutual helper effect in copulsing of dendritic cells with 2 antigens: a novel approach for improvement of dendritic-based vaccine efficacy against tumors and infectious diseases simultaneously.

To develop an efficient dendritic cell (DC)-based immunotherapy protocol, we examined whether simultaneous pulsing of DCs with a given antigen and a third-party antigen could enhance their antigen presentation capacity. Purified splenic DCs of Balb/c mice were pulsed separately with immunoglobulin G, ovalbumin, conalbumin, P15 peptide of Mycobacterium tuberculosis, and prostate-specific antigen or double combinations of the aforementioned antigens. In some settings, DCs pulsed with 1 antigen were mixed equally with those pulsed with another antigen. Antigen-pulsed DCs were injected into the footpad of syngeneic mice and proliferation of whole, CD4− and CD8− depleted lymph node cells was measured after restimulation with cognate antigen. Antigen-specific production of interferon-gamma (IFNγ) was tested in culture supernatants. Frequency of responding lymph node cells was determined by IFNγ enzyme-linked immunosorbent spot assay. Our results showed that copulsing of DCs with 2 unrelated antigens increased the capacity of DCs to induce antigen-specific T-cell proliferation against both antigens up to 16-fold. Injection of 2 populations of DCs each pulsed with a different antigen, increased proliferation of primed T cells significantly as well. Both CD4− and CD8− depleted populations showed vigorous proliferative response in copulsing system. In addition, copulsing of DCs with 2 antigens resulted in higher frequency of antigen-specific responding cells and significantly more IFNγ production. Our results clearly showed that unrelated peptides and proteins could be used to enhance efficacy of DC-based vaccines and in this system, each antigen served to help the other one, a condition that we termed as “mutual helper effect.”

REPERTOIRE AND CLONALITY OF TCELL RECEPTOR BETA VARIABLE GENES EXPRESSED IN ENDOMETRIUM AND BLOOD T CELLS OF PATIENTS WITH RECURRENT SPONTANEOUS ABORTION

Problem  Recurrent spontaneous abortion (RSA) is a relatively common disorder, the underlying causes of which are thought to be immunological in most cases.

Evaluation of thyroglobulin expression in murine reproductive organs during pregnancy.

Citation Moravej A, Jeddi‐Tehrani M, Salek‐Moghaddam AR, Dokouhaki P, Ghods R, Rabbani H, Kazemi‐Sefat GE, Shahbazi M, Zarnani AH. Evaluation of thyroglobulin expression in murine reproductive organs during pregnancy. Am J Reprod Immunol 2010; 64: 97–103

Expression profile and clonality of T-cell receptor beta variable genes in normal human endometrium.

In spite of their key immunological role, αβ+ T cells residing in endometrium have not been extensively explored. We analyzed here expression profile of TCRBV genes in normal human endometrium compared with peripheral blood.