Little is known about the immunobiology of interleukin-17 (IL-17)-producing T cells and regulatory T cells (Treg) in chronic lymphocytic leukemia (CLL). In this study, the frequencies of Th17, Tc17, and CD39(+) Treg cells were enumerated in peripheral T cells isolated from 40 CLL patients and 15 normal subjects by flow cytometry. Our results showed a lower frequency of Th17 and Tc17 cells in progressive (0.99 ± 0.12 % of total CD3(+)CD4(+) cells; 0.44 ± 0.09 % of total CD8(+) cells) compared to indolent patients (1.57 ± 0.24 %, p = 0.042; 0.82 ± 0.2 %, p = 0.09) and normal subjects (1.78 ± 0.2 %, p = 0.003; 0.71 ± 0.09 %, p = 0.04). Decrease in IL-17-producing T cells was associated with CD39(+) Treg cells expansion. Variation of IL-17-producing cells and Treg cells in indolent and progressive patients was neither associated to the expression levels of Th1- and Th2-specific transcription factors T-bet and GATA-3 nor to the frequencies of IFN-γ and IL-4-producing CD4(+) T cells in a selected number of samples. Additionally, suppressive potential of CD4(+) Treg was similar in CLL patients and normal subjects. Our data indicate that progression of CLL is associated with downregulation of IL-17-producing T cells and expansion of Treg cells, implying contribution of these subsets of T cells in the progression of CLL.

Little is known regarding the immunobiology of regulatory T (Treg) cells in hematopoietic malignancies, particularly in chronic lymphocytic leukemia (CLL). In the present study, we showed that the frequencies of CD8(+) and CD4(+) Treg cells were significantly increased in progressive as compared with indolent CLL patients and normal subjects. Enriched CD4(+) Treg cells induced a similar level of inhibition in polyclonally activated B cells and effector T cells from CLL patients and normal subjects. Our results suggest that the increase in circulating Treg cells may result in downregulation of tumor-specific immune response, leading to tumor expansion and disease progression.

Natural killer T (NKT) cells are a subset of innate immune cells displaying a limited repertoire of antigen specificities and CD1d restriction. Little is known about contribution of NKT cells in cancer initiation and progression. In this study, the frequencies of NKT-like cells, B cells expressing CD1d molecule and CD4(+) regulatory (Treg) cells were analyzed in 40 patients with chronic lymphocytic leukemia (CLL) and 15 healthy subjects by flow cytometry. Our results showed that the frequency of CD3(+)CD56(+) NKT-like cells is significantly decreased in progressive (4.9 ± 0.8 % of total CD3(+) T cells) compared with indolent (8.1 ± 1.2 %, p = 0.036) patients and healthy subjects (10.6 ± 1.7 %, p = 0.003). However, no association was found between NKT-like cell frequency and immunoglobulin heavy chain variable region gene (IGHV) mutation or CD38 and ZAP70 expression. On the other hand, expression of CD1d molecule was significantly higher in leukemic B cells of patients with CLL (75 ± 1.5 % of total CD19(+) B cells) compared to B cells from healthy subjects (59.6 ± 2.2 %, p < 0.001), with no significant difference between progressive and indolent patients. Interestingly, the frequency of Treg cells was inversely correlated with that of NKT-like cells in patients with CLL (r = -0.4, p = 0.002). Our results suggest a protective role for NKT-like cells in patients with CLL, which seems to be downregulated presumably by Treg cells.

The Wnt molecules are a family of secretory glycoproteins implicated in proliferation and differentiation of both normal and malignant cells. Despite extensive investigation of the WNT genes expression profile in various tumors, little is known about their expression in chronic lymphocytic leukemia (CLL). In this study, the expression profile of 14 WNT genes was investigated in a large number of Iranian patients with CLL. Semi-quantitative RT-PCR was performed on peripheral blood leukemic cells obtained from 62 patients with CLL. Peripheral blood mononuclear cells isolated from 11 age matched normal subjects served as control to determine baseline expression level of these genes. Our results have demonstrated significant up-regulation of WNT-3, WNT-4, WNT-5B, WNT-7B, WNT-9A, WNT-10A, and WNT-16B in patients with CLL compared to normal subjects (p < 0.05 to p < 0.0001). WNT gene expression analysis in different CLL subtypes showed a similar pattern of expression in progressive and indolent clinical subtypes. Over-expression of WNT-5A and WNT-9A genes was observed in patients with no mutation in their immunoglobulin (Ig) variable region heavy chain (Ig VH) genes compared to those with mutated Ig VH genes. Comparison between patients expressing VH1 (n = 9), VH3 (n = 40) and VH4 (n = 12) gene families, revealed down-regulation of WNT-3 and WNT-9A in VH3 positive patients. Our results indicate up-regulation of many members of the WNT gene family in CLL suggesting involvement of the Wnt canonical and/or noncanonical signaling pathways in CLL tumorigenesis.

Iranian soldiers were attacked with chemical bombs, rockets and artillery shells 387 times during the 8-years war by Iraq (1980–1988). More than 1,000 tons of sulfur mustard gas was used in the battlefields by the Iraqis against Iranian people. A high rate of morbidities occurred as the result of these attacks. This study aimed to evaluate the delayed toxic effects of sulfur mustard gas on Iranian victims. During a systematic search, a total of 193 (109 more relevant to the main aim) articles on sulfur mustard gas were reviewed using known international and national databases. No special evaluation was conducted on the quality of the articles and their publication in accredited journals was considered sufficient. High rate of morbidities as the result of chemical attacks by sulfur mustard among Iranian people occurred. Iranian researchers found a numerous late complications among the victims which we be listed as wide range of respiratory, ocular, dermatological, psychological, hematological, immunological, gastrointestinal and endocrine complications, all influenced the quality of life of exposed victims. The mortality rate due to this agent was 3%. Although, mortality rate induced by sulfur mustard among Iranian people was low, variety and chronicity of toxic effects and complications of this chemical agent were dramatic.

The mutational status of the immunoglobulin variable region heavy chain genes (IGHV) is an important prognostic marker in chronic lymphocytic leukemia (CLL). The data accumulated in the literature has largely been derived from studies conducted on Caucasian Western populations. Little is known about Asian CLL patients. In this study the IGHV genes usage and somatic hypermutation status have been investigated in 87 Iranian CLL patients. Based on a cut-off of 98% nucleotide sequence homology, 64.4% and 35.6% of the patients expressed mutated and unmutated IGHV genes, respectively, with most non-progressive patients being in the mutated group (35 ⁄ 44 vs 19 ⁄ 40; P = 0.009). Progression-free survival (PFS) and time to first treatment (TTFT) were significantly higher in our mutated and non-progressive patients compared to unmutated and progressive subtypes, respectively. The most frequently used IGHV gene was IGHV3-7 (12.6%) followed by IGHV3-30 (11.4%), IGHV3-48 (9.2%), IGHV4-39 (6.9%), and IGHV1-8 (6.9%) genes, which taken together comprised nearly half of the IGHV genes expressed in the Iranian CLL patients. Of the IGHV genes, IGHV3-7 was significantly over-represented in non-progressive compared to progressive CLL patients (P = 0.036), whereas IGHV1-69 and IGHV1-2 were expressed at a higher frequency in unmutated compared to mutated CLL patients (P < 0.03). Comparison of IGHV gene usage in our patients with that of Western CLL patients revealed significant differences in expression of IGHV1-69, IGHV3-7, IGHV3-21, and IGHV4-34 genes. Analysis of the IGHV third complementary determining region (HCDR3) sequences revealed a high frequency use of certain HCDR3 motifs, such as YYYGMDV, in our samples. These findings imply contribution of antigen selection and regional (ethnic ⁄ geo-

Fc receptor-like (FCRL) 1-5 molecules are exclusively expressed in B-cells and have recently been considered as potential targets for immunotherapy of B-cell malignancies. In this study, the expression pattern of FCRL1-5 molecules was investigated in Iranian patients with B-cell chronic lymphocytic leukemia (B-CLL). Our RT-PCR results have demonstrated that all FCRL molecules, except FCRL4, were expressed in the vast majority of the patients with B-CLL. However, comparison of the relative mRNA expression levels of FCRL between B-CLL (n 5 86) and elderly normal subjects (n 5 10) revealed significantly lower expression levels of FCRL1 (p < 0.0001), FCRL3 (p 5 0.01) and FCRL4 (p 5 0.002), but not FCRL2 or FCRL5, in cases with B-CLL. No significant differences were observed between the indolent and progressive subtypes of patients with B-CLL. Comparison between the mutated and unmutated subtypes revealed a significantly higher expression level of FCRL3 (p 5 0.017) in patients with mutated CLL. Surface and intracytoplasmic expression of FCRL1, 2, 4 and 5 in leukemic cells of 12 patients by flow cytometry revealed similar results to those obtained by RT-PCR with a few exceptions. Thus, while FCRL4 was expressed in only 2 samples at intracytoplasmic level, FCRL1 and 2 were expressed in the majority of samples, both at surface and intracytoplasm. FCRL5 protein was also detected in 10 samples, but surface expression was confirmed in only 2. Analysis of B-cells from 5 normal subjects by flow cytometry revealed higher expression levels of FCRL molecules compared to CLL. Our results indicate differential expression of FCRL molecules in B-CLL and suggest the potential implication of FCRL1 and 2 for immunotherapeutic interventions.

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