T cell responses to an HLA-A2-restricted adipophilin peptide correlate with BMI in patients with atherosclerosis.

INTRODUCTION: Atherosclerosis is an inflammatory disease causing a vast array of cardiovascular diseases. Adipophilin has been reported to be highly expressed in atherosclerotic lesions. This study investigated the possible existence of auto-reactive T cells against an HLA-A02-restricted adipophilin-derived peptide as well as peptides from Epstein-barr virus (EBV), Cytomegalovirus (CMV) and influenza (Flu) virus in patients with atherosclerosis. METHODS: HLA-A02 expression on peripheral blood mononuclear cells (PBMCs) was examined by flow cytometry. PBMCs from HLA-A02 individuals were stimulated with adipophilin, CMV, EBV, and Flu peptides at a concentration of 10 µM. Interferon (IFN)-γ production was evaluated in the culture supernatant using a commercial ELISA test. RESULTS: The levels of IFN-γ production against an HLA-A02-restricted adipophilin peptide and peptides from CMV, EBV, and Flu revealed no statistically significant differences between patients and healthy controls. However, we found a positive correlation between IFN-γ production against adipophilin and Body mass index (BMI) of patients (R = 0.8, P = 0.003), whereas no significant correlation was found in healthy controls (R = -0.267, P = 0.378). No correlation between BMI and IFN-γ production against CMV, EBV, or Flu peptides was found. DISCUSSION: Atherosclerotic patients with higher BMIs might have greater numbers of T cells against adipophilin that is highly expressed in atherosclerotic plaques. Therefore, autoimmune reactions may have a greater role in the development of atherosclerosis in individuals with higher BMI.

CagA-positive and CagA-negative Helicobacter pylori strains differentially affect the expression of micro RNAs 21, 92a, 155 and 663 in human umbilical vein endothelial cells.

Given that the basic mechanism of the effect of Helicobacter (H.) pylori in the induction of atherosclerosis remains unknown and regarding the regulatory role of micro RNAs (miRNAs) in endothelial cell (EC) functions, we aimed to investigate the effect of H. pylori on the expression of miRNAs involved in atherosclerosis (atheromiRs) and their correlation with apoptosis in human umbilical vein EC (HUVEC). HUVECs were treated with different cytotoxin associated gene A (CagA) positive and negative H. pylori derived products, then the levels of apoptosis and miR-21, 92a, 155 and 663 were measured using flowcytometry and real time-PCR methods, respectively. Although, comparing induced apoptosis and necrosis in HUVECs revealed that water extract of CagA+ H. pylori (HpWE) was more potent than CagA- one and H. pylori lipopolysacharide (Hp-LPS), no significant difference was observed between LPS extracted from CagA+ and CagA- strains. Besides, CagA+ HpWE significantly increased the levels of anti-apoptotic miR-21, and inflammatory miRNAs 155 and 663 but not miR-92a. A positive correlation was observed between apoptosis and necrosis and miR-155 as well as the expressions of miR-21 with miR-155 (P=0.024) and miR-663 (P=0.0001). As H. pylori products differentially influenced phenotypic and epigenetic changes in ECs pictured in apoptosis and in the expression of atheromiRs, we suggest that the presence of CagA molecule accompanied by these atheromiRs may act as beneficial biomarkers predicting ECs apoptosis as a sign of plaque rupture.

A Versatile Murine Model of Subcortical White Matter Stroke for the Study of Axonal Degeneration and White Matter Neurobiology.

Stroke affecting white matter accounts for up to 25% of clinical stroke presentations, occurs silently at rates that may be 5-10 fold greater, and contributes significantly to the development of vascular dementia. Few models of focal white matter stroke exist and this lack of appropriate models has hampered understanding of the neurobiologic mechanisms involved in injury response and repair after this type of stroke. The main limitation of other subcortical stroke models is that they do not focally restrict the infarct to the white matter or have primarily been validated in non-murine species. This limits the ability to apply the wide variety of murine research tools to study the neurobiology of white matter stroke. Here we present a methodology for the reliable production of a focal stroke in murine white matter using a local injection of an irreversible eNOS inhibitor. We also present several variations on the general protocol including two unique stereotactic variations, retrograde neuronal tracing, as well as fresh tissue labeling and dissection that greatly expand the potential applications of this technique. These variations allow for multiple approaches to analyze the neurobiologic effects of this common and understudied form of stroke.

CD45RO+ memory T-cells produce IL-17 in patients with atherosclerosis.

Several CD4+ T helper (Th) cell subsets are shown to play a role in atherosclerotic lesion formation and progression. We investigated the frequencies of IL-17 and IFN-γ producing CD4+ T-cell subsets in the peripheral blood mononuclear cells (PBMCs) of 10 patients with atherosclerosis and 6 individuals with normal/insignificant coronary artery disease. Th1 and Th17 memory and effector T-cells were enumerated by flowcytometry and correlated with the clinical data and lipid profiles of the subjects. We found the ex-vivo (P=0.0001) and in-vitro production of IL-17 (P=0.001) but not IFN-γ by CD4+ memory T-cells of patients. CD45RO+ memory cells were the major producers of IL-17 and the CD4+CD45RO+PD-1- T-cells of the patients produced higher levels of IFN-γ than controls (P=0.02). Positive correlations between the frequency of CD4+CD45RO+IL-17+IFN-γ- T-cells and serum LDL-C (P=0.007), triglyceride (P=0.02), and systolic (P=0.001) and diastolic (P=0.009) blood pressures (BP) were found. The frequency of CD4+CD45RO+IL-17-IFN-γ- T-cells, which was higher in controls than patients, showed negative correlations with the serum LDL-C (P=0.01) and triglyceride (P=0.02) levels and systolic (P=0.003) and diastolic (P=0.01) BPs. The ex-vivo Th17 deviation of memory T-cells in atherosclerosis and high PD-1 expression are associated with the correlates of atherogenesis such as LDL, TG, and BP.

Registered report: Interactions between cancer stem cells and their niche govern metastatic colonization.

The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by replicating selected results from a substantial number of high-profile papers in the field of cancer biology published between 2010 and 2012. This Registered report describes the proposed replication plan of key experiments from 'Interactions between cancer stem cells and their niche govern metastatic colonization' by Malanchi and colleagues, published in Nature in 2012 (Malanchi et al., 2012). The key experiments that will be replicated are those reported in Figures 2H, 3A, 3B, and S13. In these experiments, Malanchi and colleagues analyze messenger RNA levels of periostin (POSTN) in pulmonary fibroblasts, endothelial cells, and immune cells isolated from mice with micrometastases to determine which cell type is producing POSTN in the metastatic niche (Figure 2H; Malanchi et al., 2012). Additionally, they examine MMTV-PyMT control or POSTN null mice to test the effect of POSTN on primary tumor growth and metastasis (Figures 3A, 3B, and S13; Malanchi et al., 2012). The Reproducibility Project: Cancer Biology is a collaboration between the Center for Open Science and Science Exchange, and the results of the replications will be published in eLife.

A profile of transcriptomic changes in the rd10 mouse model of retinitis pigmentosa.

PURPOSE: Retinitis pigmentosa (RP) is a photoreceptor disease that affects approximately 100,000 people in the United States. Treatment options are limited, and the prognosis for most patients is progressive vision loss. Unfortunately, understanding of the molecular underpinnings of RP initiation and progression is still limited. However, the development of animal models of RP, coupled with high-throughput sequencing, has provided an opportunity to study the underlying cellular and molecular changes in this disease. METHODS: Using RNA-Seq, we present the first retinal transcriptome analysis of the rd10 murine model of retinal degeneration. RESULTS: Our data confirm the loss of rod-specific transcripts and the increased relative expression of Müller-specific transcripts, emphasizing the important role of reactive gliosis and innate immune activation in RP. Moreover, we report substantial changes in relative isoform usage among neuronal differentiation and morphogenesis genes, including a marked shift to shorter transcripts. CONCLUSIONS: Our analyses implicate remodeling of the inner retina and possible Müller cell dedifferentiation.

Elevated PD-1 expression and decreased telomerase activity in memory T cells of patients with symptomatic Herpes Zoster infection.

We investigated PD-1 levels on VZV-specific CD8+ T-cells of patients with zoster and the effect of PD-1 on the telomerase activity. CD3, CD8, CD137 and PD-1 expressions were analyzed on PBMCs from 9 symptomatic and 5 asymptomatic individuals. The effect of PD-1 blockade at the time of stimulation on the telomerase activity of non-senescent CD57-CD45RO+CD8+CD3+ memory T-cells was evaluated. PD-1 was elevated on CD8+ T-cells in patients. The frequency of PD-1+ and CD137- cells in total CD3+CD8+ T cells of patients was elevated compared to controls. Telomerase activity of non-senescent memory T-cells was lower than that of controls. Blockade of PD-1 at the time of stimulation increased telomerase activity of non-senescent memory T-cells, accompanied by increased CD137 expression. Low telomerase activity of the patients with reactivated zoster could be partially overcome by blocking PD-1 pathway.

Virally delivered channelrhodopsin-2 safely and effectively restores visual function in multiple mouse models of blindness.

Previous work established retinal expression of channelrhodopsin-2 (ChR2), an algal cation channel gated by light, restored physiological and behavioral visual responses in otherwise blind rd1 mice. However, a viable ChR2-based human therapy must meet several key criteria: (i) ChR2 expression must be targeted, robust, and long-term, (ii) ChR2 must provide long-term and continuous therapeutic efficacy, and (iii) both viral vector delivery and ChR2 expression must be safe. Here, we demonstrate the development of a clinically relevant therapy for late stage retinal degeneration using ChR2. We achieved specific and stable expression of ChR2 in ON bipolar cells using a recombinant adeno-associated viral vector (rAAV) packaged in a tyrosine-mutated capsid. Targeted expression led to ChR2-driven electrophysiological ON responses in postsynaptic retinal ganglion cells and significant improvement in visually guided behavior for multiple models of blindness up to 10 months postinjection. Light levels to elicit visually guided behavioral responses were within the physiological range of cone photoreceptors. Finally, chronic ChR2 expression was nontoxic, with transgene biodistribution limited to the eye. No measurable immune or inflammatory response was observed following intraocular vector administration. Together, these data indicate that virally delivered ChR2 can provide a viable and efficacious clinical therapy for photoreceptor disease-related blindness.

Towards optogenetic sensory replacement.

Over the last several years we have developed a rapidly-expanding suite of genetically-encoded reagents (e.g., ChR2, Halo, Arch, Mac, and others) that, when expressed in specific neuron types in the nervous system, enable their activities to be powerfully and precisely activated and silenced in response to light. If the genes that encode for these reagents can be delivered to cells in the body using gene therapy methods, and if the resultant protein payloads operate safely and effectively over therapeutically important periods of time, these molecules could subserve a set of precise prosthetics that use light as the trigger of information entry into the nervous system, e.g. for sensory replacement. Here we discuss the use of ChR2 to make the photoreceptor-deprived retina, as found in diseases such as retinitis pigmentosa, sensitive to light, enabling restoration of functional vision in a mouse model of blindness. We also discuss arrays of light sources that could be useful for delivering patterned sensory information into the nervous system.

Association of interleukin-18 gene promoter polymorphisms with breast cancer.

Interleukin-18 [IL-18] gene promoter polymorphism is reported to be a genetic risk factor for several types of cancer. The aims of this investigation were to evaluate and compare the frequencies of IL-18 gene promoter polymorphisms at positions -137 [G/C] and -607 [C/A] in breast cancer patients and healthy controls as well as to study the contribution of these data with clinicopathological parameters at diagnosis. The studied populations comprised 250 cases with breast carcinoma and 206 healthy subjects. IL-18 gene promoter polymorphisms at positions -137 and -607 were amplified in patient and control groups using allele specific polymerase chain reaction [AS-PCR]. The frequencies of GG, GC and CC genotypes of -137 SNP were 141 [56.4%], 96 [38.4%] and 13 [5.2%] in patients vs. 110 [53.4%], 72 [34.9%] and 24 [11.7%] in controls, respectively. A significant decrease of the CC genotype was observed in patients [p = 0.04]. The frequency of the CC genotype at position -137 was also significantly higher in patients with metastasis than non-metastatic patients [21.4% vs. 4.3%] [p = 0.02]. There was no significant association between genotype frequencies at position -607 with breast cancer or its clinicopathological parameters at diagnosis. Moreover, allelic frequencies at these positions did not contribute to breast cancer incidence. The distribution of IL-18 gene haplotypes and genotype combinations were not significantly different between patients and normal control individuals. This is the first report investigating the contribution of IL-18 gene promoter polymorphisms to breast cancer. These results suggest contrast effects of IL-18 gene in cancer induction and progression. Key words: Breast cancer, IL-18, polymorphism.

Cytotoxic T lymphocyte antigen-4 promoter variants in breast cancer.

CTLA4 is a coinhibitory molecule expressed mainly on activated T lymphocytes. To test the putative involvement of CTLA-4 in inhibitory state of immunity to breast cancer, we genotyped 283 patients and 245 healthy control subjects for -1722 T/C, -1661 A/G, and -318 C/T single nucleotide polymorphisms in the promoter region of the CTLA4 gene. There were no significant differences in genotype, allele, or haplotype frequencies in all three loci between patients and healthy controls. Moreover, the incidence of the most frequent haplotype combination (TAC/TAC, T -1722, A -1661, C -318) was only slightly higher among healthy controls than patients (68.4 vs. 64.8%, P = 0.2). This haplotype combination was associated with lower stages of the disease (P = 0.0007), however, and higher estrogen receptor (ER) expression in patients (P = 0.006). Association with tumor prognostic or predictive factors was also observed with certain genotypes: the -1661 AA genotype was associated with lesser lymph node (LN) involvement (P = 0.017) and higher ER expression (P = 0.004), and the -318 CC genotype with lesser LN involvement (P = 0.007). These results suggest that CTLA4 promoter variants participate in the progression of breast cancer rather than in its initial development.

Heterozygosity in CTLA-4 gene and severe preeclampsia.

OBJECTIVE: One of the major complications of pregnancy, preeclampsia makes pregnancy termination inevitable in most cases. Similarities exist between the mechanisms that maintain normal pregnancy, allograft transplants, and, it is postulated, peripheral self-tolerance. In addition, the critical role of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) molecule in maintaining self-tolerance has been established. Therefore, the frequency of CTLA-4 A49G polymorphism was investigated in severe preeclampsia. PATIENTS AND METHODS: Genomic DNA extracted from mononuclear cells of the peripheral blood of 36 pregnant women with severe preeclampsia and 151 healthy women was analyzed. A49G polymorphism in position 49 of exon-1 of the CTLA-4 gene was studied by the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) method. RESULTS: The frequency of the GG genotype was 2 (5.6%) in patients and 19 (12.6%) in controls, while the frequency of the AA genotype was 4 (11.1%) and 60 (39.7%). Interestingly, the frequency of the AG genotype was significantly higher in preeclamptic than in healthy women from the general population (83.3% vs. 47.7%; P=0.0005). CONCLUSION: These data suggest that heterozygosity in the CTLA-4 A49G allele might be a predisposing factor for severe preeclampsia. Whether the observed association results from linkage imbalance with other loci on chromosome 2 or other polymorphisms of the CTLA-4 gene or even from a preferential transfer and/or expression of one allele from a heterozygous mother to the fetus will be the subject of future investigations.

Preferential placental transfer of Helicobacter pylori specific IgG.

OBJECTIVE: To evaluate the placental transfer of Helicobacter pylori-specific IgG in Iranian mothers. METHOD: The antibodies were measured in sera of 156 mother/newborn pairs using a commercially available indirect Enzyme Linked Immunosorbent Assay (ELISA). The study population was among healthy pregnant women who attended to the Zeinabieh hospital of Shiraz University of Medical Sciences in 1999. RESULTS: In total 74.7% of mothers were seropositive and more than 82% of seropositive mothers transferred Helicobacter pylori-specific IgG antibodies to their fetuses. The mean maternal Helicobacter pylori-specific IgG was significantly higher than that of the newborns (104.01 vs. 68.30 IU/ml, p < 0.001), however, there was a good correlation between maternal and neonatal antibodies. The level of maternal Helicobacter pylori-specific IgG was significantly lower in carriers of blood group B + compared to carriers of blood groups A + and O + . However, the cord/maternal ratio of Helicobacter pylori-specific IgG was significantly higher in blood group B + phenotype compared to blood group phenotypes A + and O + . CONCLUSION: The high rate of seropositivity among mothers highlights the risk of acquisition of Helicobacter pylori infection in early infancy for Iranian children. Our results also suggest that mothers having blood group B + are more likely to transfer Helicobacter pylori-specific IgG to their neonates.

Placental transfer of tetanus-specific immunoglobulin G in Iranian mothers.

OBJECTIVES: To investigate placental transfer of anti-tetanus immunoglobulin (Ig)G antibodies in Iranian mothers. METHODS: Sera collected from 209 pregnant women and their paired infants were evaluated for tetanus-specific antibodies by a commercial enzyme-linked immunosorbent assay. RESULTS: In total, 15 (7.2%) out of 209 mothers and 12 (5.7%) out of 209 newborns were negative for anti-tetanus IgG. A highly significant correlation was observed between maternal and fetal anti-tetanus IgG (r = 0.80). The mean cord/maternal blood ratio of anti-tetanus IgG was 1.22 +/- 0.97. The mean cord/maternal blood ratio of anti-tetanus IgG in mothers with blood groups B+ and AB+ was lower than in mothers with other blood groups (p = 0.027). In addition, among mothers who had more than 0.5 IU/ml anti-tetanus IgG, a higher percentage of cases with cord/maternal blood ratio of < 1 was observed in carriers of blood groups B+ and AB+ compared to those with other blood groups (45.2% vs. 41.8%). Parity of more than 4 had a significant negative effect on both frequency of high positive sera and the mean of anti-tetanus IgG level in maternal and neonatal sera. CONCLUSIONS: A relatively high percentage of pregnant women were not immune against tetanus. It was also found that the main factors that affect infants' tetanus-specific IgG are maternal concentration of this immunoglobulin, parity and maternal blood group.

Exon-1 polymorphism of ctla-4 gene in Iranian patients with Graves' disease.

Polymorphisms in ctla-4 gene have been shown to be associated with the Graves' disease (GD) susceptibility in different populations in the world. This study was undertaken to disclose the probable association of exon-1 polymorphism of ctla-4 with GD in Iranian patients. A49G polymorphism was investigated in 90 patients and 90 age/sex matched normal healthy controls, using PCR-SSCP and PCR-RFLP methods. Frequencies of AA, AG and GG genotypes among patients were found to be 21 (23.3%), 49 (54.5%) and 20 (22.2%) while these frequencies among healthy controls were 30 (33.3%), 53 (58.9%) and 7(7.8%), respectively. A significant increase of GG genotype and G allele was observed in patients (p = 0.012 and p = 0.025). In conclusion, consistent with the results of most other studies, the presence of a G allele in position 49 of ctla-4 exon-1 is associated with susceptibility to GD in Iranian population.

High risk HPV types in southern Iranian patients with cervical cancer.

This study was undertaken to assess the rate of HPV infection in cervical carcinoma among southern Iranian patients. 101 archival cervical carcinoma tissue samples of a 10 year period were studied for the presence of HPV DNA in southern Iran by a polymerase chain reaction method. In addition, the presence of high risk HPV-16 and HPV-18 genotypes was investigated. In total, 88 (87.1%) of the samples were HPV DNA positive, of which 83 were squamous cell carcinomas and 5 were adenocarcinomas. HPV-16 genotype was detected in 26.7% of HPV positive cervical carcinomas; however, none of the samples were positive for the existence of HPV-18 genotype. Collectively, these results suggest that HPV-16 and HPV-18 are not the frequent high risk HPV types in our patients and circulating HPV types in southern Iranian population are different from many other populations.

Placental transfer of rubella-specific IgG in fullterm and preterm newborns.

OBJECTIVES: This study was undertaken to investigate placental transfer of anti-rubella IgG immunoglobulins in Iranian mothers. METHODS: In total, 231 pregnant women and their paired infants enrolled in this study of which, 197 gave birth to fullterm and 26 gave birth to preterm infants. Rubella specific antibodies were detected by an in-house whole-virus ELISA assay in maternal and cord sera of 188 fullterm and 26 preterm infants. RESULTS: A highly significant correlation was observed between anti-rubella IgG in newborns in total, in preterm and fullterm neonates with their paired mothers (P-values=0.0001, 0.002, 0.0001, respectively). A borderline significant difference was observed between mean anti-rubella IgG in fullterm and preterm neonates (P=0.04). Mean cord/maternal ratio of anti-rubella IgG was 0.83 which was surprisingly low. A significant lower anti-rubella IgG was observed in newborns born from mothers with blood group B+ than those born from mothers with blood groups A+ (P=0.04) and O+ (P=0.02), respectively. The same difference was observed between mean maternal anti-rubella IgG in those with blood groups B+ and A+ (P=0.04) and those with blood groups B+ and O+ (P=0.05). In addition, a low frequency of B+ blood group in high positive sera and a high frequency of this blood group among low positive and negative sera was detected. CONCLUSIONS: Our data suggest that the main factors that influence the infants' rubella-specific IgG concentration are maternal concentration of this immunoglobulin, maternal blood group, and neonatal gestational age.

Effects of Citrus aurantifolia concentrated extract on the spontaneous proliferation of MDA-MB-453 and RPMI-8866 tumor cell lines.

The in vitro effects of concentrated lime juice (CLJ) extract on the spontaneous proliferation of a human breast carcinoma cell line (MDA-MB-453) and a human lymphoblastoid B cell line (RPMI-8866) were investigated. CLJ extract was prepared by freeze-drying fresh fruit juice and dialyzing the concentrated extract against phosphate buffered saline in order to deplete low molecular weight micronutrients such as flavonoids as well as adjusting the pH of the extract to the physiological range. The effects of different concentrations of the CLJ extract on the spontaneous proliferative responses of the cell lines were determined by 3H-thymidine incorporation after 24 hrs of incubation. CLJ extract had no significant effect on MDA-MB-453 cell line, however, using the concentrations of 125, 250, and 500 microg/ml of CLJ extract a significant inhibition of the spontaneous proliferation of RPMI-8866 cell line was detected (P < 0.05). Due to the protein nature of the biologically active macromolecules of the CLJ extract (Gharagozloo and Ghaderi, 2001), it is reasonable to assume that the protein components of the CLJ extract may have anti-proliferative effects on tumor cell lines.

Human leukocyte antigen class II allele frequencies and haplotype association in Iranian normal population.

The polymorphism of the HLA class II genes DRB1, DQA1, and DQB1 was investigated in 100 unrelated Iranian individuals from Fars province in Southern Iran, using the restriction fragment length polymorphism (RFLP) method. Subtyping of DRB1*04, *15, and *16 alleles was performed using PCR amplification with sequence specific primes (PCR-SSP). The allele and the haplotype frequencies were calculated. The most common DRB1 alleles were DRB1*11, DRB1*15, and DRB1*04 with a frequency of 25.0%, 14.5%, and 10.5%, respectively. In contrast, the allelic frequency of DRB1*12 and DRB1*08 was very low (1.5% for each). In the DR15 group DRB1*1501 was the most prevalent variant (6.0%). Concerning DR4, the most common alleles were DRB1*0405 and DRB1*0402 (3.5% for each). Interestingly, DRB1*0402 was associated with DQB1*0302 and DRB1*0405 was associated with DQB1*0302 and DQB1*02, the latter being a rare DRB1/DQB1 haplotype in Caucasian individuals. The most frequent DQB1 alleles were DQB1*0301 (31.0%), and DQB1*05 (22.0%). The most frequent DQA1 variants were DQA1*0501 (39.0%) and DQA1*0102 (14.5%). The most common haplotype was DRB1*11-DQB1*0301-DQA1*0501 (25.0%) followed by DRB1*0301-DQB1*02-DQA1*0501 (10%) and DRB1*0701- DQB1*02-DQA1*0201 (6.5%). Data presented in this study suggest that the Iranian population shares some HLA components with populations resident in eastern and southern European countries.

Apoptotic death of neurons exhibiting peripherin aggregates is mediated by the proinflammatory cytokine tumor necrosis factor-alpha.

Peripherin, a neuronal intermediate filament protein associated with axonal spheroids in amyotrophic lateral sclerosis (ALS), induces the selective degeneration of motor neurons when overexpressed in transgenic mice. To further clarify the selectivity and mechanism of peripherin-induced neuronal death, we analyzed the effects of peripherin overexpression in primary neuronal cultures. Peripherin overexpression led to the formation of cytoplasmic protein aggregates and caused the death not only of motor neurons, but also of dorsal root ganglion (DRG) neurons that were cultured from dissociated spinal cords of peripherin transgenic embryos. Apoptosis of DRG neurons containing peripherin aggregates was dependent on the proinflammatory central nervous system environment of spinal cultures, rich in activated microglia, and required TNF-alpha. This synergistic proapoptotic effect may contribute to neuronal selectivity in ALS.