Polymorphism of the heat-shock protein gene HSP70-2 in systemic lupus erythematosus

A Review of the Mechanism of Vascular Endothelial Injury in Immunoglobulin A Vasculitis

Immunoglobulin A (IgA) vasculitis (IgAV), also known as Henoch-Schönlein purpura, is the most common form of childhood vasculitis. It is characterized by cutaneous hemorrhage, resulting from red blood cell leakage into the skin or mucosae, possibly caused by damage to small blood vessels. These acute symptoms usually disappear without treatment. Endothelial cells are distributed on the inner surfaces of blood vessels and lymphatic vessels, and have important functions in metabolism and endocrine function, as well as being the primary targets of external stimuli and endogenous immune activity. Injury to endothelial cells is a feature of IgA vasculitis. Endothelial cell damage may be related to the deposition of immune complexes, the activation of complement, inflammatory factors, and chemokines, oxidative stress, hemodynamics, and coagulation factors. Both epigenetic mechanisms and genetic diversity provide a genetic background for endothelial cell injury. Here, research on the role of endothelial cells in allergic IgA vasculitis is reviewed.

Heat shock and HSP70 regulate 5-FU-mediated caspase-1 activation in myeloid-derived suppressor cells and tumor growth in mice

Background

We have previously shown that 5-fluorouracil (5-FU) selectively kills myeloid-derived suppressor cells (MDSCs) and activates NLRP3 (NOD-leucine rich repeat and pyrin containing protein 3) inflammasome. NLRP3 activation leads to caspase-1 activation and production of IL-1β, which in turn favors secondary tumor growth. We decided to explore the effects of either a heat shock (HS) or the deficiency in heat shock protein (HSP) 70, previously shown to respectively inhibit or increase NLRP3 inflammasome activation in macrophages.

Methods

Caspase-1 activation was detected in vitro in MSC-2 cells by western blot and in vivo or ex vivo in tumor and/or splenic MDSCs by flow cytometry. The effects of HS, HSP70 deficiency and anakinra (an IL-1 inhibitor) on tumor growth and mice survival were studied in C57BL/6 WT or Hsp70^−/− tumor-bearing mice. Finally, Th17 polarization was evaluated by qPCR (Il17a, Rorc) and angiogenic markers by qPCR (Pecam1, Eng) and immunohistochemistry (ERG).

Results

HS inhibits 5-FU-mediated caspase-1 activation in vitro and in vivo without affecting its cytotoxicity on MDSCs. Moreover, it enhances the antitumor effect of 5-FU treatment and favors mice survival. Interestingly, it is associated to a decreased Th17 and angiogenesis markers in tumors. IL-1β injection is able to bypass HS+5-FU antitumor effects. In contrast, in Hsp70^−/− MDSCs, 5-FU-mediated caspase-1 activation is increased in vivo and in vitro without effect on 5-FU cytotoxicity. In Hsp70^−/− mice, the antitumor effect of 5-FU was impeded, with an increased Th17 and angiogenesis markers in tumors. Finally, the effects of 5-FU on tumor growth can be restored by inhibiting IL-1β, using anakinra.

Conclusion

This study provides evidence on the role of HSP70 in tuning 5-FU antitumor effect and suggests that HS can be used to improve 5-FU anticancer effect.

Can the hyperthermia-mediated heat shock factor/heat shock protein 70 pathway dampen the cytokine storm during SARS-CoV-2 infection?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a major global public health problem. Infection by this virus involves many pathophysiological processes, such as a "cytokine storm," that is, very aggressive inflammatory response that offers new perspectives for the management and treatment of patients. Here, we analyse relevant mechanism involved in the hyperthermia-mediated heat shock factors (HSFs)/heat shock proteins (HSP)70 pathway which may provide a possible treatment tool.

Hsp70 Gene Polymorphisms Are Associated With Disease Susceptibility and HRQOL Improvement in Chinese Han Population With Systemic Lupus Erythematosus

OBJECTIVES

The aim of this study is to investigate whether heat shock protein 70 (Hsp70) gene polymorphisms are implicated in systemic lupus erythematous (SLE) susceptibility, the efficacy of glucocorticoids (GCs) treatment, and improvement of health-related quality of life.

METHODS

A total of 499 SLE patients and 499 controls were included in a case-control study, and 468 SLE patients treated with GCs for 12 weeks were involved in a follow-up study. Patients who completed the 12-week follow-up were divided into GCs-sensitive and GCs-insensitive group by using the SLE disease activity index. The SF-36 was used to evaluate the health-related quality of life of SLE patients, and genotyping was performed by improved multiplex ligation detection reaction.

RESULTS

rs2075800 was associated with SLE susceptibility (adjusted odds ratio [ORadj], 1.437; 95% confidence interval [CI], 1.113-1.855; Padj = 0.005; PBH = 0.020 by dominant model; ORadj, 1.602; 95% CI, 1.072-2.395; Padj = 0.022; PBH = 0.029 by TT vs CC model; ORadj = 1.396; 95% CI = 1.067-1.826; Padj = 0.015; PBH = 0.029 by TC vs CC model). In the follow-up study, rs2075799 was associated with the improvement in mental health (p = 0.004, PBH = 0.044), but we failed to find any association between the efficacy of GCs and Hsp70 gene polymorphisms.

CONCLUSIONS

Hsp70 gene polymorphisms may be associated with susceptibility to SLE and improvement of mental health in Chinese Han population.

Response to oxidative stress of peripheral blood mononuclear cells from multiple sclerosis patients and healthy controls

The complex scenario of multiple sclerosis (MS) pathology involves several mechanisms, including oxidative stress response. The heat shock proteins (HSPs) are important for the protection of the cells; however, their role in MS is not clear. The present research is focused on the response of peripheral blood mononuclear cells (PBMCs) to oxidative stress and to the involvement of HSP70-2 (a protein coded by the HSPA1B gene, located in the MHC class III). To this aim, we challenged PBMCs from MS patients and healthy controls with hydrogen peroxide. Specifically, PBMCs mitochondrial activity, HSP70-2 protein expression and the production of intracellular reactive oxygen species were assessed. These parameters were also related to the HSP70-2 rs1061581 polymorphism, which is linked to the risk of developing MS. Moreover, mitochondrial activity and HSP70-2 protein levels were also related to disease severity. Overall, our results indicate that PBMCs, from both MS patients and healthy controls, may display a similar response towards an oxidative insult; within this context, HSP70-2 does not seem to be central in the protection of PBMCs. Nevertheless, the HSP70-2 rs1061581 polymorphism is related to ROS levels and appears to have a role in the different expression of HSP70-2 under oxidative stimulus.

HSP70 is a negative regulator of NLRP3 inflammasome activation

The NOD-leucine rich repeat and pyrin containing protein 3 (NLRP3) inflammasome is a multi-protein complex, aimed at producing IL-1β in response to danger signals which must be tightly regulated. Here we investigated the importance of the stress sensor, Heat Shock Protein 70 (HSP70) on NLRP3 inflammasome activation. HSP70 deficiency leads to the worsening of NLRP3-dependent peritonitis in mice. HSP70 deficiency also enhances caspase-1 activation and IL-1β production in murine Bone Marrow-Derived Macrophages (BMDMs) under NLRP3 activator treatment in vitro. This observation is associated with an increased number and size of Apoptosis associated Speck-like protein containing a CARD domain (ASC)/NLRP3 specks. Conversely, the overexpression of HSP70 in BMDMs decreases caspase-1 activation and IL-1β production under NLRP3 activator treatment. HSP70 interacts with NLRP3 and this interaction is lost upon NLRP3 inflammasome activation. Heat shock inhibits NLRP3 inflammasome activation in vitro and inhibits peritonitis in mice. Therefore this study provides evidence on the inhibitory role of HSP70 on NLRP3 inflammasome and open the possibility of treating inflammatory diseases via HSP70 induction and/or by hyperthermia.

Glycoprotein 96 polymorphisms are associated with the risk of systemic lupus erythematosus: A case-control study

AIM

To investigate the clinical implications of a genetic polymorphism in glycoprotein 96 (GP96), by analyzing the association between the genotype and haplotype of GP96 with systemic lupus erythematosus (SLE).

METHOD

We analyzed cell-surface expression of GP96 in peripheral blood mononuclear cells (PBMCs) and serum titer of anti-GP96 antibody of SLE patients. Single nucleotide polymorphisms and deletion mutants of GP96 were detected by two-dimensional gene scanning (TDGS). Odds ratios with 95% confidence intervals (CI) were determined for each genotype and haplotype through the chi-square test.

RESULTS

In total, 216 Korean SLE patients and 215 age- and sex-matched healthy controls were enrolled. In SLE patients, as opposed to healthy controls, cell-surface expression of GP96 among human leukocyte antigen-DR+ PBMCs (76.4% vs 45.5%, respectively, P < 0.001) and serum anti-GP96 antibody titers (0.98 vs 0.50, respectively, P = 0.012) increased. TDGS revealed six polymorphic sites in GP96, two of which were significantly associated with SLE (exon 1, g.-7C>G, odds ratio [OR] 1.78, 95% CI 1.16-2.75, P = 0.009; exon 17, g.17009_17011del, OR 1.76, 95% CI 1.18-2.64, P = 0.006). Two haplotypes (121111, 211212) were strongly associated with SLE (OR 8.92, 95% CI 1.10-72.6, P = 0.041; OR 3.03, 95% CI 1.22-7.50, P = 0.017, respectively) and specific clinical manifestations (discoid rash, arthritis, renal disorder, neurologic disorder, and hematologic disorder). Haplotype-based analysis revealed a stronger association between GP96 and SLE than did genotype-based analysis.

CONCLUSION

The two polymorphisms, each in exons 1 and 17 of GP96 are potential genetic risk factors of SLE. Two haplotypes 121111 and 211212 are related to not only SLE but also specific clinical manifestations.

A Case of Henoch-Schonlein Purpura Associated with Rotavirus Infection in an Elderly Asian Male and Review of the Literature

Patient: Male, 73

Final Diagnosis: Henoch-Schönlein purpura (HSP)

Symptoms: Abdominal pain • bloating • blood in stool • nausea • vomiting

Medication: —

Clinical Procedure: EGD • colonoscopy • kidney biopsy • skin biopsy • arthrocentesis

Specialty: Rheumatology

Heat shock proteins in the kidney

Heat shock proteins (Hsps) are essential to cell survival through their function as protein chaperones. The role they play in kidney health and disease is varied. Hsp induction may be either beneficial or detrimental to the kidney, depending on the specific Hsp, type of cell, and context. This review addresses the role of Hsps in the kidney, including during development, as osmoprotectants, and in various kidney disease models. Heat shock transcription factor, activated by a stress on renal cells, induces Hsp elaboration and separately regulates immune responses that can contribute to renal injury. Induced Hsps in the intracellular compartment are mostly beneficial in the kidney by stabilizing and restoring cell architecture and function through acting as protein chaperones. Intracellular Hsps also inhibit apoptosis and facilitate cell proliferation, preserving renal tubule viability after acute injury, but enhancing progression of cystic kidney disease and malignancy. Induced Hsps in the extracellular compartment, either circulating or located on outer cell membranes, are mainly detrimental through enhancing inflammation pathways to injury. Correctly harnessing these stress proteins promises the opportunity to alter the course of acute and chronic kidney disease.

Heat shock protein 70-2 and tumor necrosis factor-α gene polymorphisms in Chinese children with Henoch-Schönlein purpura

BACKGROUND

Henoch-Schönlein purpura (HSP) or IgA-associated vasculitis is related to immune disturbances. Polymorphisms of the heat shock protein 70-2 gene (HSP70-2) and the tumor necrosis factor-a gene (TNF-α) are known to be associated with immune diseases. The purpose of this study was to investigate the likely association of HSP70-2 (+1267A/G) and TNF-α (+308A/G) gene polymorphisms with HSP in children.

METHODS

The polymerase chain reaction restriction fragment length polymorphism method was used to detect the HSP70-2 and TNF-α polymorphisms in 205 cases of children with HSP and 53 controls; and the association of these polymorphisms with HSP and HSP nephritis (HSPN) was analyzed.

RESULTS

The G/G genotypic frequencies at the +1267A/G position of HSP70-2 in the HSP group (22.9%) were significantly higher than those in the healthy control group (9.4%) (χ(2)=4.764, P<0.05). The frequencies of the A/A, A/G and G/G genotypes of HSP70-2 in patients in the nephritis-free group and the HSPN group showed no statistically significant difference. The A/A genotype frequency at the +308G/A position of TNF-α in the HSP group was 8.3%, which was higher than that in the control group (χ(2)=6.447, P<0.05). The A allele frequency of TNF-α in the HSP group was higher than that in the control group, with a statistically significant difference (χ(2)=7.241, P<0.05).

CONCLUSIONS

The HSP70-2 (+1267A/G) and TNF-α (+308G/A) gene polymorphisms were associated with HSP in children. The G/G homozygosity of HSP70-2 and the A/A homozygosity of TNF-α may be genetic predisposing factors for HSP.

Heat-shock protein 70-2 BB genotype is associated with reduced risks of the steroid-dependent and refractory phenotypes of ulcerative colitis

Previous studies have demonstrated the protective role of inducible heat-shock protein (HSP) 70 in intestinal cells. The HSP70-2 gene has a PstI site due to an A-G transition at the 1,267 position and different genotypes are associated with various levels of mRNA expression. The present study aimed to clarify the effect of the HSP70-2 polymorphism on the risk of ulcerative colitis (UC), including its clinical phenotypes. A total of 121 patients with UC and 500 healthy control (HC) subjects participated in the study. To assess the polymorphisms at the 1,267 position of the HSP70-2 gene, restriction fragment length polymorphism analysis was performed. The subjects in the study were classified by disease behavior, severity and extent of disease. Although no significant difference of the HSP70-2 genotype distribution was identified between the HC and UC groups, the BB genotype exhibited a lower risk of the steroid-dependent phenotype [odds ratio (OR), 0.12; 95% confidence interval (CI), 0.02-0.95; P=0.02]. The same genotype was also associated with a lower risk of the refractory phenotype (OR, 0.16; 95% CI, 0.04-0.73; P=0.01). There was no direct correlation between the polymorphism of the HSP70-2 gene and UC susceptibility. However, there was an association between a reduced risk of the steroid-dependent and refractory phenotypes of UC and the BB genotype.

Are Hsp70 protein expression and genetic polymorphism implicated in multiple sclerosis inflammation?

Genetic and environmental factors contribute to disease Multiple Sclerosis (MS) susceptibility, the most prevalent neurological pathology affecting young individuals in Western countries. We focused our attention on HSP70-2, an inducible chaperon induced under stress conditions. Genotype analysis of HSP70-2 (+1267 A/G) polymorphism revealed a significant association between the minor allele G and presence of MS (OR:1.31, 95% CI: 1.02-1.69, P = 0.039). In addition, Hsp70-2 protein content in vitro from PBMC was significantly lower in MS patients with GG genotype compared to AA genotype, indicating an implication of the G allele of HSP70-2 gene polymorphism in the development of MS.

Overexpression of HSPA2 is correlated with poor prognosis in esophageal squamous cell carcinoma

Background

Heat shock-related 70 kDa protein 2 (HSPA2) has been identified as a potential cancer-promoting protein expressed at abnormal levels in a subset of cancers. However, its important role in esophageal squamous cell carcinoma (ESCC) is hardly known by people. The purpose of this study is to assess HSPA2 expression and to explore its role in ESCC.

Methods

Thirty ESCC samples, paired adjacent non-cancerous tissues and normal esophageal tissues, were collected for HSPA2 detection by quantitative RT-PCR (qRT-PCR) and western blotting. Additionally, the expression of HSPA2 in ESCC and adjacent non-cancerous tissues from 120 patients was analyzed by immunohistochemistry, and correlated with clinicopathological parameters and patients’ outcome.

Results

HSPA2 mRNA and protein were overexpressed in ESCC tissues. Overexpression of HSPA2 was significantly associated with primary tumor, TNM stage, lymph node metastases and recurrence, respectively (all, P <0.05). Kaplan-Meier curves showed that elevated HSPA2 expression was associated with shorter disease-free survival and overall survival in ESCC patients. Cox multivariate regression analysis revealed that overexpression of HSPA2 was an independent prognostic factor in disease-free survival and overall survival for ESCC patients (hazard ratio was 2.115 and 2.210, respectively, P <0.05).

Conclusions

Our findings demonstrate that overexpression of HSPA2 may contribute to the malignant progression of ESCC and present a novel prognostic indicator for ESCC patients.

Crohn's disease and polymorphism of heat shock protein gene HSP70-2 in the Chinese population

BACKGROUND AND AIMS

Crohn's disease (CD) is a multifactorial disorder with a pivotal role of the genetic component. A single nucleotide polymorphism in heat shock protein 70-2 (HSP70-2) has been shown to be associated with a severe clinical course in CD. The purpose of this study was to identify associations between the HSP70-2 polymorphism and the clinical courses of CD in the Chinese population.

METHODS

One hundred patients with CD and 190 healthy individuals were genotyped for the HSP70-2 PstI polymorphism by restriction fragment length polymorphism analysis.

RESULTS

The genotype frequency of the PstI polymorphism did not differ between patients and controls. The A allele was higher in CD patients than in controls (61% vs 52%, P = 0.047, odds ratio [OR] = 1.423, 95% confidence interval [CI]: 1.004-2.015). Furthermore, this polymorphism was higher in the penetrating or fistula surgery of CD patients than in controls (63% vs 52%, P = 0.049, OR = 1.530, 95% CI: 1.001-2.337; Table ). But there was no significant difference between the penetrating or fistula surgery patients and no surgery patients (P = 0.673, OR = 0.883, 95% CI: 0.495-1.574). We used multivariate analysis to determine the effects of genotypes on sex, disease behavior, disease location, and so on. No significant difference was observed between these parameters and genotype.

CONCLUSION

This study reported that the allele A of PstI polymorphism was the association between CD and HSP70-2 gene in the Chinese population. It was also association between penetrating or fistula surgery of CD and HSP70-2 gene in the Chinese population.

Polymorphisms in the Hsp70 gene locus are genetically associated with systemic lupus erythematosus

BACKGROUND

Heat shock proteins (Hsps) play a role in the delivery and presentation of antigenic peptides and are thought to be involved in the pathogenesis of multifactorial diseases.

OBJECTIVE

To investigate genes encoding cytosolic Hsp70 proteins for associations of allelic variants with systemic lupus erythematosus (SLE).

METHODS

Case-control studies of two independent Caucasian SLE cohorts were performed. In a haplotype-tagging single-nucleotide polymorphism approach, common variants of HspA1L, HspA1A and HspA1B were genotyped and principal component analyses were performed for the cohort from the Oklahoma Medical Research Foundation (OMRF). Relative quantification of mRNA was carried out for each Hsp70 gene in healthy controls. Conditional regression analysis was performed to determine if allelic variants in Hsp70 act independently of HLA-DR3.

RESULTS

On analysis of common genetic variants of HspA1L, HspA1A and HspA1B, a haplotype significantly associated with SLE in the Erlangen-SLE cohort was identified, which was confirmed in the OMRF cohort. Depending on the cohorts, OR ranging from 1.43 to 1.88 and 2.64 to 3.16 was observed for individuals heterozygous and homozygous for the associated haplotype, respectively. Patients carrying the risk haplotype or the risk allele more often displayed autoantibodies to Ro and La in both cohorts. In healthy controls bearing this haplotype, the amount of HspA1A mRNA was significantly increased, whereas total Hsp70 protein concentration was not altered.

CONCLUSIONS

Allelic variants of the Hsp70 genes are significantly associated with SLE in Caucasians, independently of HLA-DR3, and correlate with the presence of autoantibodies to Ro and La. Hence, the Hsp70 gene locus appears to be involved in SLE pathogenesis.

Correlation between some Th1 and Th2 cytokine receptor gene polymorphisms and systemic lupus erythematosus in Chinese patients

BACKGROUND

Genetic factors seem to play a significant role in the susceptibility to systemic lupus erythematosus (SLE). Some researchers have described amino acid polymorphisms within the interleukin-4 receptor (IL-4R) [isoleucine50valine (Ile50Val), arginine576glutamine (Arg576Gln), etc.], the IL-10R (G241A and G520A), and the interferon-gamma receptor (IFN-gammaR) [valine14methionine (Val14Met) and glutamine64arginine (Gln64Arg)].

METHODS

The Ile50Val genotypes were examined by the reverse transcription-polymerase chain reaction-single-strand conformation polymorphism (RT-PCR-SSCP) method and DNA sequencing. The RT-PCR-restriction fragment length polymorphism (RT-PCR-RFLP) method was used to detect the Arg576Gln, G241A, G520A, Val14Met, and Gln64Arg genotypes.

RESULTS

There were significant differences in the genotype frequencies of Ile50/Ile50, G520/G520, and G520/A520 between the SLE group and healthy control group. There was a positive correlation between the IL-4R Ile50/Ile50 genotype and the susceptibility to SLE (P = 0.022). This was also found for the IL-10R G520/G520 (P = 0.004) and G520/A520 (P = 0.055) genotypes. The risk of SLE susceptibility was increased in individuals with the genotype combinations Ile50/Ile50 and Gln576/Arg576 (P = 0.056) and G241/G241 and G520/G520 (P = 0.004). The IFN-gammaR2 Arg64/Arg64 genotype decreased the risk of SLE (P = 0.047). A decreased risk of development of SLE was detected in individuals with the genotype combination IFN-gammaR2 Arg64/Arg64 and IFN-gammaR1 Val14/Val14 (P = 0.004).

CONCLUSIONS

The IL-4R Ile50/Ile50 and IL-10R2 G520/G520 and G520/A520 genotypes were shown to determine the susceptibility to SLE in a Chinese population, as were the combinations Ile50/Ile50 and Gln576/Arg576, and G241/G241 and G520/G520.

The interferon-gamma receptor gene polymorphisms (Val14Met and Gln64Arg) are not associated with systemic lupus erythematosus in Chinese patients

Genetic polymorphism is a difference in DNA sequence among individuals, groups, or populations that give rise to different forms. Differences in DNA sequences that occur naturally in a population. Single nucleotide substitutions, insertions and deletions of nucleotides and repetitive sequences (microsatellites) are all examples of polymorphism. The position at which such a sequence difference is found is a polymorphic site. A single nucleotide substitution is called a single nucleotide polymorphism (SNP). SNPs can occur in coding parts of the gene. If they result in genetic code change, amino-acid polymorphism would occur. The heterodimeric IFN-gamma receptor (IFNGR) complex was made up of two receptor subunits including IFNGR-1 and IFNGR-2. There exist five dbSNP alleles in IFNGR1 exon region and six dbSNP alleles in IFNGR2. Some researchers had found that the greatest risk of the development of systemic lupus erythematosus (SLE) be detected in the individuals who had the Met14/Val14 genotype or the combination of IFNGR1 Met14/Val14 genotype and IFNGR2 Gln64/Gln64 genotype in Japanese patients. So we aimed to assess the association between two polymorphisms within the IFNGR gene (A88G and A839G) and SLE in Chinese patients. This study included 154 patients with SLE and 159 unrelated healthy controls. We examined the IFNGR genotype by the reverse transcription-polymerase chain reaction (RT-PCR)-single-strand conformation polymorphism method, RT-PCR-restriction fragment length polymorphism method and DNA sequencing. Genotype frequencies between SLE patients and controls were compared and relationship between genotype frequencies and clinical manifestations of SLE were evaluated. We found that IFNGR2 Arg64/Arg64 genotype decrease the risk of SLE (OR = 2.326, 95% CI 1.181-4.581, Fisher P = 0.015), and the same as IFNGR2 Arg64/Arg64 genotype and IFNGR1 Val14/Val14 genotype combination (OR = 2.420, 95% CI 1.206-4.854, Fisher P = 0.013). The allelic frequency of Val14/Met14 is significantly higher in the patients with oral ulcer or thrombocytopenia when compared with patient without these clinical feature (OR = 4.630, 95% CI 1.370-15.640, Fisher P = 0.021; or OR = 6.368, 95% CI 2.009-20.191, Fisher P = 0.003). On the contrary, the allelic frequency of Val14/Val14 is lower in the patients with oral ulcer or thrombocytopenia than those without these clinical feature (OR = 0.216, 95% CI 0.064-0.730, Fisher P = 0.021; or OR = 0.157, 95% CI 0.050-0.498, Fisher P = 0.003). And after data analysis, we also find that the allelic frequency of Gln64/Gln64 is lower in the patients with arthritis when compared with patient without arthritis (OR = 0.369, 95% CI 0.166-0.818, Fisher P = 0.017). We can conclude that the IFNGR polymorphisms (Val14Met and Gln64Arg) are protective in SLE in Chinese patients. We describe a novel association between Val14/Met14 carriage and patients with oral ulcer or thrombocytopenia.

Heat shock protein gene 70-2 polymorphism is differentially associated with the clinical phenotypes of ulcerative colitis and Crohn's disease

BACKGROUND AND AIM

A single nucleotide polymorphism in heat shock protein 70-2 (HSP70-2) has been shown to be associated with a severe clinical course in Crohn's disease (CD), but it is not known if such a relationship exists in ulcerative colitis (UC). The aim of the present study was to identify associations between the HSP70-2 polymorphism and the clinical courses of CD and UC in Koreans.

METHODS

Restriction fragment length polymorphism analysis was performed for HSP70-2 polymorphisms using the PstI-cleavage site present in the B allele but not in the A allele of the DNA obtained from 101 patients with CD, 144 patients with UC, and 245 age- and sex-matched healthy controls. Study subjects were classified by disease behavior, severity and extent of disease.

RESULTS

In CD, multivariate analysis showed that the AA genotype of HSP70-2 polymorphisms was associated with non-perforating disease (OR 10.10, 95% CI 1.66-15.38) and male sex (OR 3.56, 95% CI 1.04-12.23), and that the BB genotype was associated with severe CD (OR 12.03, 95% CI 1.60-101.56). In contrast, multivariate analysis for UC showed that the AA genotype was associated with severe UC (OR 2.02, 95% CI 1.34-3.03).

CONCLUSIONS

CD patients with BB genotype of HSP70-2 polymorphism tend to experience a more severe clinical course and allele A is associated with more severe UC. HSP70-2 polymorphism may be used to predict CD and UC phenotypes, which can illuminate immunological differences in CD and UC.

Crohn's disease and polymorphism of heat shock protein gene HSP70-2 in the Tunisian population

BACKGROUND AND AIMS

Crohn's disease is a multifactorial disorder with a pivotal role of the genetic component. HSP70-2 gene, located in IBD3 region, has a PstI polymorphic site associated recently with Crohn's disease especially with a perforating form. In this study, we sought to determine whether this polymorphism was associated with Crohn's disease in the Tunisian population and its correlation with clinical manifestation of the disease.

METHODS

In all, 148 patients with Crohn's disease and 81 healthy individuals were genotyped for the HSP70-2 PstI polymorphism by restriction fragment length polymorphism analysis.

RESULTS

The allele and genotype frequency of the PstI polymorphism did not differ between patients and controls. Furthermore, this polymorphism was not associated with specific disease behavior.

CONCLUSION

This study reported the absence of association between Crohn's disease and HSP70-2 gene in the Tunisian population. The allele A of PstI polymorphism was not associated with phenotype of the disease.

Polymorphisms of the interleukin-4 gene in chinese patients with systemic lupus erythematosus in Taiwan

We aimed to evaluate the relationship between two polymorphisms of the IL4 gene (-590T/C and intron 3) and systemic lupus erythematosus in Chinese patients in Taiwan. This study included 91 patients with systemic lupus erythematosus (SLE) and 163 unrelated, age matched healthy controls living in the same area. The typing of -590T/C and intron 3 VNTR (variable number of tandem repeats) polymorphisms were performed by PCR-RFLP and PCR, respectively. Allelic frequencies and carriage rates between SLE patients and controls were compared, and the relationship between allelic frequencies and clinical manifestations of SLE was evaluated. The genotype frequencies of IL-4 intron 3 were found to differ significantly between SLE patients with and without discoid rash (chi-square test, P = 0.03 5). The allelic frequency of intron 3 RP1 was significant different in the patients with discoid rash when compared to patients without this clinical feature (OR = 3.70, 95% CI 2.04-6.72, chi2 test, P = 0.029). The RP1/RP1 homozygous carriage was significantly associated with patients with discoid rash when compared to patients without this clinical feature (OR = 6.04, 95% CI 2.81-12.95, P = 0.01). The allelic frequency of -590T was significant different in the patients with discoid rash when compared to patients without this clinical feature (OR = 3.44, 95% CI 1.88-6.31, chi-square test, P=0.04). The T/T homozygous carriage was significantly associated with patients with discoid rash when compared to patients without this clinical feature (OR = 5.41, 95% CI 2.50-11.68, P = 0.02). We describe a novel association between RPI/RPI and T/T homozygous carriage and patients with discoid rash. The role of the intron 3 polymorphism of the IL4 gene in SLE remains unclear and further substantiation based on larger patient samples is needed.

Heat shock protein 70-2+1267 AA homozygotes have an increased risk of septic shock in adults with community-acquired pneumonia

OBJECTIVE

Heat shock protein (HSP)70-2 is an important immunomodulatory protein induced in response to inflammatory stimuli. We assessed whether HSP70-2+1267 genotype influenced the risk of septic shock in a prospective cohort study of community-acquired pneumonia and whether HSP70-2+1267 genotype is a better predictor of septic shock than the genotype at lymphotoxin-alpha +250.

DESIGN

Prospective cohort study.

SETTING

A large, nonprofit, private hospital system in Memphis, TN.

PATIENTS

Adults admitted with community-acquired pneumonia between 1998 and 2001. Septic shock was defined according to consensus criteria (American College of Chest Physicians/Society of Critical Care Medicine, 1992).

INTERVENTIONS

Blood sampling.

MEASUREMENTS AND MAIN RESULTS

A total of 343 subjects were enrolled; 30 had septic shock. HSP70-2+1267 and lymphotoxin-alpha +250 genotype was determined using polymerase chain reaction and restriction enzyme digestion. HSP70-2+1267 AA genotype was the strongest predictor of septic shock (p =.0005; relative risk, 3.5). Lymphotoxin-alpha +250 AA genotype was also associated with an increased risk of septic shock (p =.002; relative risk, 2.7). Logistic regression analysis found only age (p =.04) and HSP70-2+1267 genotype (p =.006) were predictors of septic shock. The greatest risk of septic shock was associated with carriage of the HSP70-2+1267 A/lymphotoxin-alpha +250 A haplotype (p <.0001).

CONCLUSIONS

HSP70-2+1267 genotype is a stronger predictor of septic shock in patients with community-acquired pneumonia than lymphotoxin-alpha +250 genotype.

Molecular chaperones in the kidney

The normal milieu of the kidney includes hypoxia, large osmotic fluxes, and an enormous amount of fluid/solute reabsorption. Renal adaptation to these conditions requires a host of molecular chaperones that stabilize protein conformation, target nascent proteins to their final intracellular destination, and prevent protein aggregation. Under physiologic or pharmacologic stress, inducible molecular chaperones provide additional mechanisms for repairing or degrading non-native proteins and for inhibiting stress-induced apoptosis. In contrast to intracellular chaperones, chaperones present on the cell surface regulate the immune system and have cytokine-like effects. A diverse range of chaperones and chaperone functions provide the renal cell with an armamentarium of responses to improve the chances of survival.

Heat shock protein 70 gene polymorphisms in Mexican patients with spondyloarthropathies

OBJECTIVE

To investigate the role of HSP70 genes as contributors to genetic susceptibility of the spondyloarthropathies (SpA) in the Mexican population.

METHODS

The study included 150 patients with SpA (undifferentiated spondyloarthropathy (uSpA) 68, ankylosing spondylitis (AS) 60, and reactive arthritis 22) and 158 healthy controls. HSP70-1, HSP70-2 and HSP70-hom genotypes were analysed by the polymerase chain reaction-restriction fragment length polymorphism technique. Statistical methods included the Mantel-Haenzel, chi(2), Fisher's exact test, and Woolf's method for odds ratio (OR).

RESULTS

HSP70-2 B/B genotype frequency was increased in the whole group of patients with SpA (pC<0.05, OR=4.3), as well as in the different clinical subgroups (pC<0.05, OR=4.2 for AS; pC<0.05, OR=4.4 for uSpA; and pC<0.05, OR=4.1 for ReA). This frequency remained significantly increased when the patients with B27 negative SpA were analysed. On the other hand, HSP70-hom locus analysis showed significantly increased frequency of A allele in the whole group of SpA (pC<0.05, OR=3.4), as well as in the groups with AS (pC<0.05, OR=5.6) and with uSpA (pC<0.05, OR=3.1), when compared with healthy controls. In this case, also, the genotype A/A was increased in the whole group of SpA (pC<0.05, OR=4.5), as well as in patients with AS (pC<0.05, OR=6.4) and with uSpA (pC<0.05, OR=3.7). When the patients with B27 negative SpA were analysed the frequencies of HSP70-hom A allele and A/A genotype remained significantly increased in the whole group of SpA (pC<0.05, OR=3.2 for the A allele and pC<0.05, OR=4.2 for the A/A genotype) and in the uSpA subgroup (pC<0.05, OR=3.8 for the A allele and pC<0.05, OR=4.3 for the A/A genotype).

CONCLUSION

In addition to the association of SpA with HLA-B27, there is a significant association of HSP70-2 and HSP70-hom alleles with SpA in Mexicans. This association seems to be independent of the susceptibility conferred by HLA-B27 in the group of patients with uSpA.

Analysis of hsp70 gene polymorphism in allergic asthma

BACKGROUND

Allergic asthma is a multifactorial and probably multigenic inflammatory disease of the upper airways, and has been associated with the HLA class II alleles DR4 and DR7. Here we investigated possible associations with other polymorphic susceptibility/resistance genes located within the major histocompatibility complex, i.e., the genes coding the major 70-kDa heat-shock proteins (HSP; Hsp70) hsp70-1, hsp70-2, and hsp70-HOM, whose products are overexpressed in the bronchi of asthmatic patients.

METHODS

Genomic DNA was extracted from peripheral blood lymphocytes or buccal epithelial cells of 48 patients with allergic asthma and 31 selected nonatopic control subjects, in whom we previously reported a strong association of atopy with DR4/DR7 alleles.

RESULTS

No evidence was found for an independent role of hsp70 gene polymorphism in susceptibility to allergic asthma. However, hsp70 alleles might be involved in extended haplotypes of HLA markers.

CONCLUSIONS

Our data suggest that Hsp70 overexpression in asthma results from complex interactions between environmental exposures and genetic background rather than from specific genetic variations in hsp70 genes.

[Immunogenetic bases of systemic lupus erythematosus in humans]

INTRODUCTION

Systemic lupus erythematosus (SLE) is an autoimmune disease of unknown pathogenesis. Familial studies and concordance rates among affected twins suggest that human SLE has a strong genetic basis.

CURRENT KNOWLEDGE AND KEY POINTS

Recent studies have emphasized that SLE, like other autoimmune diseases, is a complex genetic trait with contributions of both major histocompatibility complex (MHC) associated genes and multiple non-MHC genes. Recent significant advances have been made in the genetic analysis of complex traits, which allow the identification of new candidate genes in SLE. Among the genes reviewed in this article, some polymorphisms of Fc gamma receptor genes and other genes or loci localized on the long arm of the human chromosome 1 appear to be very promising.

FUTURE PROSPECTS AND PROJECTS

The identification of new susceptibility genes in SLE will certainly provide important insights into the breakdown of self-tolerance mechanisms leading to autoimmune diseases. To achieve this objective, the recruitment of a large number of genetic traits of multiplex families presenting with SLE is therefore essential. More than 125 multiplex families have been collected to date in France.