Family study of the major histocompatibility complex in HLA DR3 negative patients with systemic lupus erythematosus

Susceptibility to systemic lupus erythematosus (SLE) is known to be governed by genes in the HLA region of the 6th chromosome. From previous studies it has not been possible to distinguish between the effects of null genes for the complement component C4 and HLA-DR3, because of the marked linkage disequilibrium between DR3 and a null allele of C4A (C4A QO) in caucasoid populations. We report here an immunogenetic study of 44 cases of SLE, selected because they were DR3 negative. Eighteen of the 30 Caucasoid cases (60%) had extended HLA haplotypes with a C4 null allele, compared with 22 of 60 (37%) of a control panel of 60 DR3 negative normal Caucasoid subjects. This difference is significant (chi 2 = 4.41; 0.05 greater than P greater than 0.01). Of 14 non-caucasoid patients analysed, 10 had a C4 null allele. It is concluded that the null alleles of the C4 A and B genes are themselves directly responsible for conferring susceptibility to SLE.     

Graves病患者外周血单个核细胞上催乳素受体mRNA的表达

目的:了解弥漫性毒性甲状腺肿(Graves disease,GD)患者外周血单个核细胞(peripheral blood mononuclear cells,PBMC)上催乳素受体(prolactin receptor,PRLR)mRNA表达及血清催乳素(prolactin,PRL)水平的变化。方法:选取新诊断或未治疗GD患者为病例组(GD组,19例),健康体检者为正常对照组(NC组,12例);测定入选者PBMC上PRLR mRNA表达及血清PRL水平。结果:1)GD组及NC组PBMC上均有PRLR表达,GD组患者PRLR表达量明显高于NC组(P<0.05);2)GD组患者血清PRL水平较NC组轻度增高,但差异无统计学意义(P>0.05)。结论:GD患者PBMC的PRLR mRNA表达增加,PRL可能参与了GD的自身免疫过程。     

Hyperprolactinemia and autoimmune diseases

The autoimmune diseases are more common in females. The sex hormones have an important role in this gender bias, mainly estrogen and prolactin (PRL) which modulate the immune response. PRL is secreted from the pituitary gland and other organs and cells mainly the lymphocytes. PRL has an immunostimulatory effect and promotes autoimmunity: PRL impairs the negative selection of autoreactive B lymphocytes occurring during B cell maturation into fully functional B cells. PRL has an anti-apoptotic effect, enhances proliferative response to antigens and mitogens and enhances the production of immunoglobulins and autoantibodies. Hyperprolactinemia (HPRL) is observed in multi-organ and organ specific autoimmune diseases like systemic lupus erythematosus (SLE) rheumatoid arthritis (RA), Sjogren's syndrome (SS), Hashimoto's thyroiditis (HT) and multiple sclerosis (MS). There is no consistent correlation between PRL levels and disease activity. Murine models and small studies in SLE patients suggest some role of dopamine agonists in the therapy of those diseases. The genetic factor may have a role in humans as in animal models. The PRL isoform has an important effect on the bioactivity on prolactin receptors (PRL-Rs).     

Expression of prolactin receptor and prolactin in normal and malignant thyroid: A tissue microarray study

Objective There is increasing evidence involving prolactin (PRL) and its receptor (PRLR) in the development of different cancers. The aim of the present study was to investigate the expression of PRLR and PRL in human thyroid tissues. Design and Methods Using tissue microarray (TMA) by immunohistochemical staining, we examined the expression level of PRLR and PRL in 314 specimens from 71 thyroid cancer patients and 15 normal thyroid samples. Results Expression of the PRLR was observed in 93.3% of normal thyroid samples and in 76.1% of all thyroid cancers, while expression of PRL was observed in only 10% of medullary thyroid carcinomas and not at all in the other specimens, whether normal or neoplastic. Moreover, results suggested an overexpression of PRLR in 70% of medullary thyroid carcinomas, whereas 53.3% of poorly differentiated thyroid carcinomas showed a negative pattern of staining (p=0.014 vs normal). Conclusions Present data revealed, for the first time, a widespread expression of PRLR in normal and neoplastic human thyroid tissues as well as a scarce expression of PRL, observed only in a few medullary thyroid carcinomas. Whether the overexpression of PRLR observed in medullary thyroid carcinomas or the underexpression of PRLR observed in poorly differentiated thyroid carcinomas play a contributory role in the oncogenesis of these tumors remains to be determined.     

Prolactin receptor expression in gynaecomastia and male breast carcinoma

Aims:  Despite the well-established function of prolactin (PRL) in normal breast development, its role in breast cancer pathogenesis is still controversial. PRL activity is dependent on the activation of a transmembrane protein, the PRL receptor (PRLR). The aim was to evaluate and compare PRLR expression in gynaecomastia and male breast carcinoma (MBC).
Methods and results:  PRLR expression was detected immunohistochemically in 30 cases of gynaecomastia and 30 cases of MBC. The whole series was also assessed for oestrogen receptors (ER), progesterone receptors (PR) and androgen receptors (AR). A cut-off of 10% was used as the criterion for positivity. Histological type and tumour differentiation were evaluated. Pathological stage was assessed [Tumour Node Metastasis (TNM)-International Union Against Cancer system]. Statistical analysis was performed with Fisher's exact test. PRLR positivity was seen in 20% of gynaecomastia cases and in 60% of MBC cases ( P  = 0.003). In gynaecomastia immunoreactivity was predominantly observed in luminal cell borders, whereas in MBC the reactivity was heterogeneous and mainly cytoplasmic. There was no statistically significant correlation between PRLR expression and ER, PR, AR, pTNM, or histological grade.
Conclusions:  PRLR is significantly more expressed in MBC than in gynaecomastia, and with different patterns of reactivity, suggesting a role for PRL in male breast carcinogenesis.     

Lipogenesis impaired in periparturient rats exposed to altered gravity is independent of prolactin and glucocorticoid secretion

Perturbed prolactin (PRL) secretion and concomitant downregulation of PRL receptor (PRLR) in periparturient dams exposed to altered gravity are linked to aberrant lipogenesis and reduced neonatal survival. PRL and glucocorticoids (GC) are known to modulate PRLR expression. We hypothesized that improving levels of PRLR would mitigate the increased gravity [hypergravity (HG)]-induced effects of impaired mammary lipogenesis and increase neonatal survival. The objective of this study was to determine if prepartum PRL or GC supplementation would override the HG-induced repression of PRLR along with lipogenic genes and increase tissue fatty acid synthesis. Pregnant rats were exposed to either 2g (HG) or kept at 1g (control) from day 11 of gestation (G11) through Postnatal day 1 (P1). HG exposed rats were supplemented with either PRL or corticosterone or a placebo from G13 to P1. On P1, mammary, liver and adipose tissues were collected to measure glucose incorporation into lipids and mRNA abundance of PRL long and short form receptors (Prlr-l, Prlr-s), glucocorticoid receptor (Nr3c1), Acetyl CoA carboxylase-α (Acaca), fatty acid synthase (Fasn), lipoprotein lipase (Lpl), Sterol Regulatory Element Binding Protein-1 (Srebp1) and protein kinase B (Akt1) genes by quantitative polymerase chain reaction (qPCR). PRL and GC supplementation had a limited effect on lipogenesis in the three tissues of HG group likely due to their inability to increase abundance of key down-regulated genes, including Prlr-l and Nr3c1. There was no difference in the abundance of genes coding for milk proteins or those associated with milk fat globule formation and secretion. These data suggest that reduced lipogenesis in HG exposed dams is independent of PRL and GC secretion but may be associated with dysregulation of multiple metabolic regulators at the level of mRNA expression.     

Prolactin and autoimmunity

Sex hormones, especially estrogen and prolactin (PRL), have an important role in modulating the immune response. PRL is secreted from the pituitary gland as well as other organs and cells particularly lymphocytes. PRL has an immune stimulatory effect and promotes autoimmunity. PRL interferes specifically with B cell tolerance induction, enhances proliferative response to antigens and mitogens and increases the production of immune globulins, cytokines and autoantibodies. Hyperprolactinemia (HPRL) in women present with clinical manifestations of galactorrhea, primary or secondary amenorrhea, delayed menarche or a change in the menses either in the amount or in the regularity. Furthermore in the last 2 decades multi-organ and organ specific autoimmune diseases like systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjogren's syndrome (SS), Hashimoto's thyroiditis (HT), multiple sclerosis (MS), psoriasis, hepatitis C patients, Beh?et's disease, peripartum cardiomyopathy (PPCM) and active celiac disease were discussed to be associated with HPRL. There is data showing correlation between PRL level and diseases activity in few diseases. Genetic factors may have a role in humans as in animal models. The PRL isoforms based on the differences in the amino acid sequence and size of the cytoplasmic domain have an important effect on the bioactivity on prolactin receptors (PRL-Rs).     

泌乳素促进类风湿关节炎患者外周血单个核细胞分泌白细胞介素-6

目的:探讨类风湿关节炎(RA)患者血清泌乳素(PRL)水平与疾病活动程度的关系,以及PRL促进外周血单个核细胞(PBMCs)分泌白细胞介素-6(IL-6)的机制。方法:收集我院2015年3月至9月40例初治RA患者临床及实验室资料。采用化学发光免疫分析法(CLIA)检测血清PRL水平,ELISA检测IL-6水平,RT-q PCR检测泌乳素受体(PRLR)mRNA的表达,Western blot法检测MAPK通路相关蛋白p-p38的蛋白水平。结果:RA患者血清PRL水平明显升高(P0.01),活动期RA患者PRL水平明显高于非活动期RA患者(P0.01)。PRL水平与DAS28评分、ESR和CRP呈正相关(P0.01)。RA患者PBMCs中PRLR水平明显升高(P0.01)。PRL可诱导PBMCs分泌IL-6,siRNA沉默PRLR或采用MAPK通路抑制剂可抑制IL-6的产生。结论:RA患者血清PRL升高与DAS28评分、ESR和CRP呈正相关,PRL可作为预测RA严重程度的指标。PRL通过与PRLR相互作用,激活p38 MAPK通路,从而促进IL-6分泌。     

Prolactin promoter polymorphism (-1149 G/T) is associated with anti-DNA antibodies in Mexican patients with systemic lupus erythematosus

Prolactin (PRL) is a 23-kDa protein hormone that is synthesized mainly by the anterior pituitary gland. However, PRL can also be synthesized and secreted by extrapituitary tissues, particularly immune cells. A biallelic polymorphism (-1149 G/T) in the prolactin promoter has been shown to be functionally important, as modulation of prolactin expression has been associated with SLE in some populations. We have performed an association study using Mexican patients with SLE. We used qPCR to determine the SNP allele and genotype frequencies. We did not find statistically significant differences in allele and genotype frequencies between patients and healthy controls. However, we found a statistically significant association between the G allele and the presence of anti-dsDNA antibodies in serum (Allele frequency (G): P?=?0.005; Genotyping frequency (GG): P?=?0.001, OR?=?7.8, 95% CI 3.59-27.1). Our data demonstrate that the prolactin promoter polymorphism -1149 G/T does not significantly contribute to SLE disease susceptibility but does predispose carriers to other immunological changes.     

Prolactin Promoter Polymorphism (−1149 G/T) is Associated with ANTI–DNA Antibodies in Mexican Patients with Systemic Lupus Erythematosus

Prolactin (PRL) is a 23-kDa protein hormone that is synthesized mainly by the anterior pituitary gland. However, PRL can also be synthesized and secreted by extrapituitary tissues, particularly immune cells. A biallelic polymorphism (?1149 G/T) in the prolactin promoter has been shown to be functionally important, as modulation of prolactin expression has been associated with SLE in some populations. We have performed an association study using Mexican patients with SLE. We used qPCR to determine the SNP allele and genotype frequencies. We did not find statistically significant differences in allele and genotype frequencies between patients and healthy controls. However, we found a statistically significant association between the G allele and the presence of anti–dsDNA antibodies in serum (Allele frequency (G): P?=?0.005; Genotyping frequency (GG): P?=?0.001, OR?=?7.8, 95% CI 3.59–27.1). Our data demonstrate that the prolactin promoter polymorphism ?1149 G/T does not significantly contribute to SLE disease susceptibility but does predispose carriers to other immunological changes.     

Prolactin may be a promising therapeutic target for myasthenia gravis: hypothesis and importance

Myasthenia gravis (MG) is an autoimmune disease that affects the transmission signals from nerves to muscles. The basic pathology is the production of anti-acetylcholine receptor (AChR) antibodies (AChRAb) which is the consequence for the generation of autoreactive T lymphocytes responsing to AChR. However, the molecular mechanism of MG and the production of autoreactive T lymphocytes remain elusive. Recently beside its pivotal role in reproduction, the pituitary hormone prolactin (PRL) has been attributed to an immunomodulatory function. Furthermore it has been shown to be expressed in T cells and conversely it also affects the function of T cells, such as directly stimulating the proliferation and survival of T lymphocytes. In addition, elevated PRL levels frequently are described in autoimmune diseases, such as systemic lupus erythematosus (SLE) and multiple sclerosis (MS). So we hypothesized that the stimulating effect of PRL on T-cells function may be implied in the pathogenesis of MG and, perhaps, prolactin may be a promising therapeutic target for MG.     

Identification and sequence analysis of prolactin receptor and its differential expression profile at various developmental stages in striped hamsters

Prolactin (PRL) plays critical roles in regulation of biological functions with the binding of specific prolactin receptor (PRLR). Revealing the expression patterns of PRLR at different developmental stages is beneficial to better understand the role of PRL and its mechanism of action in striped hamsters. In this study, the cDNA sequence of PRLR (2866-base-pairs) was harvested from the pituitary of mature female striped hamsters (Cricetulus barabensis) that contains an 834-base-pair 5′-untranslated region (1-834 bp), a 1848-base-pair open reading frame (835-2682 bp), and a 184-base-pair 3′-untranslated region (2683-2866). The 1848-base-pair open reading frame encodes a mature prolactin-binding protein of 592 amino acids. In the mature PRLR, two prolactin-binding motifs, 12 cysteines, and five potential Asn-linked glycosylation sites were detected. Our results showed that the PRLR mRNA quantity in the hypothalamus, pituitary, ovaries, or testis was developmental-stage-dependent, with the highest level at sub-adult stage and the lowest level at old stage. We also found that PRLR mRNAs were highest in pituitary, medium level in hypothalamus, and lowest in ovaries or testis. PRLR mRNAs were significantly higher in males than in females, except in the hypothalamus and pituitary from 7-week-old striped hamsters. Moreover, the PRLR mRNAs in the hypothalamus, pituitary, and ovaries or testis were positively correlated with the expression levels of GnRH in the hypothalamus. These results indicated that the PRLR has conserved domain in striped hamster, but also possesses specific character. PRLR has multiple biological functions including positively regulating reproduction in the striped hamster.     

生长激素和泌乳素在SLE患者血清中的表达及其与SLE病情程度的相关性研究

目的 研究生长激素(GH)和泌乳素(PRL)在SLE患者血清中的表达及其与SLE病情程度的相关性.方法 将105例SLE患者根据活动评分分为4个等级,分别为无活动患者,轻度活动患者,中度活动患者,重度活动患者.选取86例正常健康者作为对照组.每组抽取静脉血5mL,ELISA试剂盒检测血清中GH和PRL的水平.结果 SLE患者血清中GH和PRL的水平较正常对照组显著升高(P＜0.01),且不同病理分级中的水平也不同,其中重度组的水平最高,中度、轻度、无活动期患者血清中的水平依次降低,但均比正常对照组水平高(P＜0.01).结论 GH、PRL在SLE患者血清中的表达较正常对照组显著升高,且随着病情程度的加重,其水平逐渐增加,这为SLE患者的进一步研究提供了有力的理论依据.     

系统性红斑狼疮患者血清泌乳素水平的检测及其临床意义

目的：探讨系统性红斑狼疮(SLE)患者血清泌乳素(PRL)水平检测的临床意义。方法：应用免疫放射量度分析法测定了75例SEE患者与25例健康人血清PRL水平。结果：SLE患者血清PRL水平明显高于正常对照组，且活动期升高更明显；高泌乳素血症(HPRL)发生率为40％，伴HPRL的患者肾损害发生率明显高于血清PRL正常者；血清PRL水平与SLEDM评分、抗ds-DNA抗体滴度倒数呈正相关，与C3呈负相关。结论：SLE患者血清PRL水平升高与病情活动相关，其检测可作为监测狼疮病情活动性的指标之一；血清PRL水平升高与肾脏损害相关，提示PRL可能在SLE肾损害中起作用。     

Evaluating the role of the 620W allele of protein tyrosine phosphatase PTPN22 in Crohn's disease and multiple sclerosis

The 620W allele of PTPN22 has been associated with susceptibility to several different forms of chronic inflammatory disease, including Type 1 diabetes (T1D), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and autoimmune thyroiditis (AIT). We set out to explore its possible role in two other inflammatory diseases: multiple sclerosis (MS) and Crohn's disease (CD). In our cohort of 496 MS trios from the United Kingdom, we observed reduced transmission of the PTPN22 620W allele. The CD sample consisted of 169 trios as well as 249 cases of CD with their 207 matched control subjects collected in the province of Québec, Canada; there was also no evidence of association between the PTPN22 620W allele and susceptibility for CD. Pooled analyses combining our data with published data assessed a total of 1496 cases of MS and 1019 cases of CD but demonstrated no evidence of association with either disease. Given the modest odds ratios of known risk alleles for inflammatory diseases, these analyses do not exclude a role for the PTPN22 allele in susceptibility to CD or MS, but they do suggest that such a putative role would probably be more modest than that reported so far in T1D, RA, SLE, and AIT.     

HLA-DRB1*15 Confers Susceptibility to Juvenile SLE But is Not Associated with Disease Presentation: An Egyptian Study

The etiology of Systemic lupus erythematosus (SLE) seems to be multifactorial including environmental as well as genetic factors. Major histocompatibility complex (MHC) genes especially HLA-DRB1 and HLA-DQB1 are strongly implicated in susceptibility to SLE. Moreover ethnicity has been found to have a significant role in both disease susceptibility and disease expression. This study was carried out to determine HLA-DRB1 allele association with SLE susceptibility and disease presentation in Egyptian children with juvenile onset SLE. HLA-DRB1 allele typing was done using polymerase chain reaction-sequence-specific oligonucleotide probe for 65 juvenile Egyptian SLE patients and 150 healthy controls. p-values were corrected for the number of the alleles tested (Pc). HLA-DRB1*15 g allele was significantly increased in SLE children versus controls (OR = 4.76; 95% CI = 1.83–12.4; p = 0.001 and Pc = 0.012). No HLA-DRB1 allele was found to be statistically significant associated with musculoskeletal, cutaneous, hematologic, cardiac or neuropsychiatric manifestations in SLE patients (p > 0.05). Moreover no statistically significant association was found between HLA-DRB1 alleles and clinical presentation or histologic classes of lupus nephritis. The current work suggests that HLA-DRB1*15g allele may be a susceptibility allele in Egyptian children with SLE but is not related to clinical presentation of SLE.     

Association of tumor necrosis factor receptor 2 (TNFR2) polymorphism with susceptibility to systemic lupus erythematosus

Multiple genetic as well as environmental factors are considered to be involved in the development of systemic lupus erythematosus (SLE). A number of previous studies have suggested a possible role for tumor necrosis factor (TNF) in the pathogenesis of SLE. In addition, one of the candidate loci suggested by the genome-wide linkage analysis corresponds to the chromosomal position encompassing the TNF receptor 2 gene (TNFR2). The purpose of this study was to analyze the polymorphism of TNFR2 and its possible association with the susceptibility to SLE, using the case-control association analysis. Polymorphism screening of the exons containing previously reported nonsynonymous base substitutions was carried out by the polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) method, using genomic DNA from 81 Japanese patients with SLE and 207 healthy individuals. Two alleles were present in exon 6, coding for methionine (196M) and arginine (196R) at position 196. 30 of 81 patients (37.0%) with SLE were positive for the 196R allele, which was significantly more frequent compared with 39 of 207 healthy individuals (18.8%) (chi2=10.6, df=l, P=0.001, odds ratio=2.53, 95% CI: 1.45-4.43). Genotype analysis revealed that the presence of one 196R allele was sufficient for rendering susceptibility. The association of 196R allele with SLE was independent from that of HLA-DRB1*1501. In conclusion, the TNFR2 196R allele was found to be significantly associated with the susceptibility to SLE in the Japanese population. Further population and functional studies will be of particular importance to establish TNFR2 as one of the susceptibility genes to SLE.     

A genetic marker within the CD44 gene confirms linkage at 11p13 in African-American families with lupus stratified by thrombocytopenia,but genetic association with CD44 is not present

Systemic lupus erythematosus (SLE) is complicated from both a clinical and genetic standpoint. We have stratified SLE families by the presence of thrombocytopenia, which is associated with increased mortality among SLE patients, and found genetic linkage at chromosome 11p13 in African-American families. In the present study we have evaluated CD44, a gene very close (0.5 cM) to the peak LOD score marker, as a candidate gene. Using a newly identified short DNA repeat within the CD44 gene, we find a LOD score of 2.7, which confirms linkage within this genetic interval. However, using a panel of four single nucleotide markers spanning the CD44 gene, we find no genetic association with SLE. Therefore, these data further suggest an SLE susceptibility gene at 11p13, but also imply that an ancestral mutation in the CD44 gene does not account for the linkage.