Micro RNAs upregulated in Vitiligo skin play an important role in its aetiopathogenesis by altering TRP1 expression and keratinocyte-melanocytes cross-talk

Translation of genes is regulated by many factors including microRNAs (miRNAs). miRNA profiling of lesional and non-lesional epidermal RNA from 18 vitiligo patients revealed significant upregulation of 29 miRNAs in the lesional epidermis, of which 6 miRNAs were transfected in normal human epidermal keratinocytes (NHEKs) to study their downstream effects using quantitative proteomics. Many proteins involved in oxidative stress, Vesicle trafficking, Cellular apoptosis, Mitochondrial proteins and Keratins were regulated after miRNA transfections in the keratinocytes. However, tyrosinase related protein-1 (TRP1/TYRP1), a melanogenesis protein, was consistently downregulated in NHEKs by all the six miRNAs tested, which was quite intriguing. TRP1 was also downregulated in lesional epidermis compared with non-lesional epidermis. Since melanocytes synthesize and transfer melanosomes to the surrounding keratinocytes, we hypothesized that downregulation of TRP1 in NHEKs may have a role in melanosome transfer, which was confirmed by our co-culture experiments. Downregulation of TRP1 in keratinocytes negatively affected the melanosome transfer from melanocytes to keratinocytes resulting in melanin accumulation which may be leading to melanin induced cytotoxicity in melanocytes. Regulation of key processes involved in aetiopathogenesis of vitiligo along with TRP1 suggests that miRNAs act in an integrated manner which may be detrimental for the loss of melanocytes in vitiligo.

Association and expression of the antigen-processing gene PSMB8, coding for low-molecular-mass protease 7, with vitiligo in North India: case-control study

BACKGROUND

Vitiligo is a multifactorial, autoimmune, depigmenting disorder of the skin where aberrant presentation of autoantigens may have a role.

OBJECTIVES

To study the association of two antigen-processing genes, PSMB8 and PSMB9, with vitiligo.

METHODS

In total 1320 cases of vitiligo (1050 generalized and 270 localized) and 752 healthy controls were studied for the PSMB9 exon 3 G/A single-nucleotide polymorphism (SNP), PSMB8 exon 2 C/A SNP and PSMB8 intron 6 G/T SNP at site 37 360 using polymerase chain reaction (PCR)-restriction fragment length polymorphism. Real-time PCR was used for transcriptional expression of PSMB8 and cytokines. Expression of ubiquitinated proteins and phosphorylated-p38 (P-p38) was studied by Western blotting.

RESULTS

Significant increases in PSMB8 exon 2 allele A (P < 2.07 × 10^-6 , odds ratio 1·93) and genotypes AA (P < 1.03 × 10^-6 , odds ratio 2·51) and AC (P < 1.29 × 10^-6 , odds ratio 1·63) were observed in patients with vitiligo. Interferon-γ stimulation induced lower expression of PSMB8 in peripheral blood mononuclear cells of cases compared with controls, suggesting impaired antigen processing, which was confirmed by accumulation of ubiquitinated proteins in both lesional and nonlesional skin of patients with vitiligo. Expression of proinflammatory cytokines - interleukin (IL)-6, IL-1β and IL-8 - was higher in the lesional skin. P-p38 expression was variable but correlated with the amount of ubiquitinated proteins in the lesional and nonlesional skin, suggesting that the inflammatory cytokine responses in lesional skin could be a result of both P-p38-dependent and -independent pathways.

CONCLUSIONS

The PSMB8 exon 2 SNP is significantly associated with vitiligo. Accumulation of ubiquitinated proteins in skin of cases of vitiligo suggests their aberrant processing, which may promote the development of the disease.

Mapping architectural and transcriptional alterations in non-lesional and lesional epidermis in vitiligo

In vitiligo, chronic loss of melanocytes and consequent absence of melanin from the epidermis presents a challenge for long-term tissue maintenance. The stable vitiligo patches are known to attain an irreversible depigmented state. However, the molecular and cellular processes resulting in this remodeled tissue homeostasis is unclear. To investigate the complex interplay of inductive signals and cell intrinsic factors that support the new acquired state, we compared the matched lesional and non-lesional epidermis obtained from stable non-segmental vitiligo subjects. Hierarchical clustering of genome-wide expression of transcripts surprisingly segregated lesional and non-lesional samples in two distinct clades, despite the apparent heterogeneity in the lesions of different vitiligo subjects. Pathway enrichment showed the expected downregulation of melanogenic pathway and a significant downregulation of cornification and keratinocyte differentiation processes. These perturbations could indeed be recapitulated in the lesional epidermal tissue, including blunting of rete-ridges, thickening of stratum corneum and increase in the size of corneocytes. In addition, we identify marked increase in the putrescine levels due to the elevated expression of spermine/spermidine acetyl transferase. Our study provides insights into the intrinsic self-renewing ability of damaged lesional tissue to restore epidermal functionality in vitiligo.

Do we really need to differentiate mesenchymal stem cells into insulin-producing cells for attenuation of the autoimmune responses in type 1 diabetes: immunoprophylactic effects of precursors to insulin-producing cells

BACKGROUND

Type 1 diabetes (T1D) is a multifactorial autoimmune disorder where pancreatic beta cells are lost before the clinical manifestations of the disease. Administration of mesenchymal stem cells (MSCs) or MSCs differentiated into insulin-producing cells (IPCs) have yielded limited success when used therapeutically. We have evaluated the immunoprophylactic potentials of precursors to insulin-producing cells (pIPCs) and IPCs in nonobese diabetic (NOD) mice to ask a basic question: do we need to differentiate MSCs into IPCs or will pIPCs suffice to attenuate autoimmune responses in T1D?

METHODS

Bone marrow-derived MSCs from Balb/c mice were characterized following the International Society for Cellular Therapy (ISCT) guidelines. MSCs cultured in high-glucose media for 11 to 13 passages were characterized for the expression of pancreatic lineage genes using real-time polymerase chain reaction. Expression of the PDX1 gene in pIPCs was assessed using Western blot and fluorescence-activated cell sorting (FACS). Triple-positive MSCs were differentiated into IPCs using a three-step protocol after sorting them for cell surface markers, i.e. CD29, CD44, and SCA-1. Nonobese diabetic mice were administered pIPCs, IPCs, or phosphate-buffered saline (PBS) into the tail vein at weeks 9 or 10 and followed-up for 29-30 weeks for fasting blood glucose levels. Two consecutive blood sugar levels of more than 250 mg/dl were considered diabetic.

RESULTS

MSCs grown in high-glucose media for 11 to 13 passages expressed genes of the pancreatic lineage such as PDX1, beta2, neurogenin, PAX4, Insulin, and glucagon. Furthermore, Western blot and FACS analysis for PDX-1, a transcription factor necessary for beta cell maturation, confirmed that these cells were precursors of insulin-producing cells (pIPCs). NOD mice administered with pIPCs were better protected from developing diabetes with a protective efficacy of 78.4% (p < 0.009); however, administration of IPCs gave protective efficacy of 55% at the end of 28-30 weeks.

CONCLUSIONS

Precursors to insulin-producing cells seem to have better potential to arrest autoimmune response in type 1 diabetes when administered before the onset of the disease in NOD mice. When translated to humans, autologous mesenchymal stem cells grown in high-glucose media for 10 to 13 passages may have beneficial effects in individuals at high risk of developing type 1 diabetes.

Efficacy and Safety of Mycobacterium indicus pranii as an adjunct therapy in Category II pulmonary tuberculosis in a randomized trial

Prolonged treatment of tuberculosis (TB) often leads to poor compliance, default and relapse, converting primary TB patients into category II TB (Cat IITB) cases, many of whom may convert to multi-drug resistant TB (MDR-TB). We have evaluated the immunotherapeutic potential of Mycobacterium indicus pranii (MIP) as an adjunct to Anti-Tubercular Treatment (ATT) in Cat II pulmonary TB (PTB) patients in a prospective, randomized, double blind, placebo controlled, multicentric clinical trial. 890 sputum smear positive Cat II PTB patients were randomized to receive either six intra-dermal injections (2 + 4) of heat-killed MIP at a dose of 5 × 10⁸ bacilli or placebo once in 2 weeks for 2 months. Sputum smear and culture examinations were performed at different time points. MIP was safe with no adverse effects. While sputum smear conversion did not show any statistically significant difference, significantly higher number of patients (67.1%) in the MIP group achieved sputum culture conversion at fourth week compared to the placebo (57%) group (p = 0.0002), suggesting a role of MIP in clearance of the bacilli. Since live bacteria are the major contributors for sustained incidence of TB, the potential of MIP in clearance of the bacilli has far reaching implications in controlling the spread of the disease.

Classical autophagy proteins LC3B and ATG4B facilitate melanosome movement on cytoskeletal tracks

Macroautophagy/autophagy is a dynamic and inducible catabolic process that responds to a variety of hormonal and environmental cues. Recent studies highlight the interplay of this central pathway in a variety of pathophysiological diseases. Although defective autophagy is implicated in melanocyte proliferation and pigmentary disorders, the mechanistic relationship between the 2 pathways has not been elucidated. In this study, we show that autophagic proteins LC3B and ATG4B mediate melanosome trafficking on cytoskeletal tracks. While studying melanogenesis, we observed spatial segregation of LC3B-labeled melanosomes with preferential absence at the dendritic ends of melanocytes. This LC3B labeling of melanosomes did not impact the steady-state levels of these organelles but instead facilitated their intracellular positioning. Melanosomes primarily traverse on microtubule and actin cytoskeletal tracks and our studies reveal that LC3B enables the assembly of microtubule translocon complex. At the microtubule-actin crossover junction, ATG4B detaches LC3B from melanosomal membranes by enzymatic delipidation. Further, by live-imaging we show that melanosomes transferred to keratinocytes lack melanocyte-specific LC3B. Our study thus elucidates a new role for autophagy proteins in directing melanosome movement and reveal the unconventional use of these proteins in cellular trafficking pathways. Such crosstalk between the central cellular function and housekeeping pathway may be a crucial mechanism to balance melanocyte bioenergetics and homeostasis.

Does the presence of Klebsiella pneumoniae carbapenemase and New Delhi metallo-β-lactamase-1 genes in pathogens lead to fatal outcome?

INTRODUCTION

Infections due to multidrug-resistant (MDR) pathogens are a medical challenge. There is considerable apprehension among clinicians regarding pathogens reported as carrying New Delhi metallo-β-lactamase-1 (NDM) and Klebsiella pneumoniae carbapenemase (KPC) genes from their patients. In the face of extremely high rates of antimicrobial resistance, it is essential to gauge the clinical significance of isolation of pathogens carrying these genes from clinical samples. This study compares the outcome of patients infected with pathogens carrying NDM/KPC genes versus those without these genes.

METHODS

The study was conducted over a 1-year period at a Level-1 trauma centre. Hospital-acquired infections were diagnosed on the basis of CDC's criteria. The correlation of isolation of a multi-resistant pathogen carrying KPC or NDM genes with the clinical outcome was ascertained.

RESULTS

A total of 276 consecutive patients admitted to the Intensive Care Units/wards of the JPNA Trauma Centre were included in this study. Of the 371 isolates recovered from these patients, 116 were from patients who had a fatal outcome. The difference in prevalence of blaNDMand blaKPCwas not significant in any genera of Gram-negative pathogens isolated from patients who survived versus those who had a fatal outcome.

CONCLUSION

Isolation of MDR pathogens carrying NDM/KPC genes from clinical samples is not always a harbinger of a fatal outcome. Efforts should be made to prevent cross-transmission of these pathogens.

Presence of Autoreactive, MHC Class I-Restricted, Calcium-Sensing Receptor (CaSR)-Specific CD8+ T Cells in Idiopathic Hypoparathyroidism

CONTEXT

Major histocompatibility complex class I allele HLA-A*26:01 and human leukocyte antigen (HLA) supertype A01 (STA01) are increased in idiopathic hypoparathyroidism (IH). However, cell-mediated autoimmune responses directed against the calcium-sensing receptor (CaSR) have not been demonstrated.

OBJECTIVE

To study CaSR-specific cytotoxic T-cell responses in peripheral blood mononuclear cells of IH patients.

DESIGN

Twenty-four peptides of CaSR (RH1 to RH24) were evaluated for their ex vivo potential to stimulate PBMCs from IH patients and controls in interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assays.

SETTING

Tertiary patient care center and National Institute of Immunology, New Delhi, India.

PATIENTS AND OTHER PARTICIPANTS

Forty-five patients with IH attending the endocrine clinic of the All India Institute of Medical Sciences and 22 healthy controls.

MAIN OUTCOME MEASURES

Major histocompatibility complex class-I restricted, CaSR-specific cytotoxic CD8+ T-cell responses evaluated by IFN-γ ELISPOT assay.

RESULTS

Of IH patients, 82.2% showed IFN-γ-secreting cells when stimulated ex-vivo with CaSR peptides. Peptides RH7, RH9, and RH16 elicited HLA supertype A01-restricted responses in IH. RH8, RH14, RH15, RH20, and RH21 peptides induced significantly higher responses in STA01+ IH patients compared with healthy controls irrespective of their supertype A01 status.

CONCLUSIONS

Our ex vivo IFN-γ ELISPOT assays demonstrate the presence of CaSR-specific memory CD8+ T cells in the peripheral circulation of patients with IH, suggesting the role of cell-mediated autoimmune responses in the etiopathogenesis of IH.

Rare Presentation of Chorioadenoma Destruens as Acute Haemoperitoneum Mimicking Ruptured Ectopic Pregnancy

Gestational trophoblastic neoplasms (GTN) are proliferative degenerative disorders of placental elements and include complete or partial mole (90%), invasivemole (5-8%), choriocarcinoma (1-2%) and placental site tumor (1-2%). Chorioadenoma destruens is a trophoblastic tumor, characterized by myometrial invasion through direct extension or via venous channels. We present a case of invasive mole eroding uterus and uterine vasculature, causing sudden rupture of uterus with massive haemoperitoneum mimicking ectopic pregnancy. A 20 year old G1P0 at 6 weeks gestation presented in Casualty of Kasturba Hospital complaining of severe acute onset lower abdominal pain for one hour. Clinical examination revealed shock. Sonography suggested ectopic pregnancy and immediate exploratory laparotomy was decided. On laparotomy, 2000cc of haemoperitoneum was noted. Grape like vesicles protruding through fundal perforation with profuse active bleeding was seen. Bleeding persisted despite evacuation. Step wise uterine devascularisation failed to achieve haemostasis. Total abdominal hysterectomy was performed as a life saving measure.

A study of as-grown, poled and reduced Rh-doped KNbO3 single crystals by high-resolution X-ray diffraction, Raman scattering, photoluminescence and dielectric measurements

As-grown and chemically reduced Rh-doped (1500 p.p.m.) KnbO3 single crystals grown by the Czochralski method have been characterized. Reduction of the grown crystals at different levels was carried out under a mixture of CO and CO2 gases as the crystals were grown with excess oxygen. The effect of reduction and poling on crystalline perfection was studied by high-resolution X-ray diffraction (HRXRD) using a multi-crystal X-ray diffractometer developed in-house. The diffraction curves of the as-grown, electrically poled, moderately reduced and heavily reduced single-crystal specimens show remarkable differences. The studies by HRXRD reveal that poling has some influence on the improvement of crystalline perfection, while chemical reduction has a great influence on crystalline perfection; at moderate reduction the crystal becomes nearly perfect, but when the reduction is very heavy the crystal quality decreases slightly, although it is still better than for unreduced samples. Asymmetry of the diffraction curves with respect to the peak position reveals that the as-grown specimens contain a high concentration of both vacancies and self-interstitials. After poling, the concentration of self-interstitial defects is lowered to some extent. When the specimen is moderately chemically reduced, the scattered intensity on both sides of the peak is greatly reduced, showing that the concentrations of both vacancies and interstitials are reduced to a great extent owing to chemical reduction. This clearly indicates that, as a result of the chemical reduction of oxygen in the crystal, crystalline perfection is enhanced significantly. However, under heavy chemical reduction, the number of vacancy defects is increased to a significant extent. Raman scattering, dielectric and photoluminescence studies also show interesting features, with excellent correlation with the degree of crystalline perfection influenced by the processes of reduction and poling.

Presence of strong association of the major histocompatibility complex (MHC) class I allele HLA-A*26:01 with idiopathic hypoparathyroidism

CONTEXT

The pathogenesis of isolated hypoparathyroidism, also referred to as idiopathic hypoparathyroidism (IH), is not clear. There is a paucity of information related to the immunogenetic basis of the disease due to its rarity. A recurrent theme of several autoimmune disorders is aberrant antigen presentation.

OBJECTIVE

We investigated for the association of alleles of the human leukocyte antigen (HLA) class I and II loci with IH.

PATIENTS AND CONTROLS

A total of 134 patients with IH and 902 healthy controls from the same ethnic background participated in the study.

RESULTS

There was a significant increase of HLA class I alleles HLA-A*26:01 [P < 1.71 × 10(-34); odds ratio (OR) = 9.29; 95% confidence interval (CI) = 6.08-14.16] and HLA-B*08:01 (P < 8.19 × 10(-6); OR = 2.59; 95% CI = 1.63-4.04) in patients with IH compared to healthy controls. However, the association of A*26:01 was primary because B*08:01 was in linkage disequilibrium with A*26:01. Although the major histocompatibility complex (MHC) is very polymorphic, several alleles of HLA loci share key residues at anchor positions in the peptide binding pockets such that similar peptides may be presented by different MHC molecules encoded by the same locus. These allelic forms with similar anchoring amino acids have been clustered in supertypes. An analysis of HLA-A locus supertypes A01, A02, A03, and A04 revealed that supertype A01 was significantly increased (P < 9.18 × 10(-9); OR = 2.95) in IH compared to controls. However, this increase in the supertype A01 was contributed by A*26:01 because 68.7% of the A01 samples had A*26:01. Other alleles of the supertype did not show any significant differences.

CONCLUSION

The strong association of HLA-A*26:01 suggests an important role of MHC class I-mediated presentation of autoantigenic peptides to CD8(+) cytotoxic T cells in the pathogenesis of IH. These data provide evidence for the autoimmune etiology of IH akin to other autoimmune disorders like type 1 diabetes and rheumatoid arthritis.

Interleukin-4 genetic variants correlate with its transcript and protein levels in patients with vitiligo

BACKGROUND

Vitiligo is an acquired pigmentary disorder resulting from loss of melanocytes. Interleukin (IL)-4 has been shown to stimulate B-cell proliferation, to regulate immunoglobulin class switching (IgG1 and IgE) and to promote T-cell development. Polymorphisms in the IL4 gene are known to increase its expression, thereby implicating its role in vitiligo susceptibility.

OBJECTIVES

To explore intron 3 VNTR (IVS3) and -590 C/T (rs2243250) promoter polymorphisms in the IL4 gene and to correlate them with the IL4 transcript, serum IL-4 and IgE levels to achieve genotype-phenotype correlation in patients with vitiligo from Gujarat. A replication study was done in a North Indian population.

METHODS

The case-control study was performed to investigate these polymorphisms in 505 patients and 744 controls in Gujarat, and 596 patients and 397 controls in North India by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism analysis. IL4 transcript levels were monitored by real-time PCR. Serum IL-4 and IgE levels were measured by enzyme-linked immunosorbent assay and electrochemiluminescence immunoassay, respectively.

RESULTS

The genotype frequencies differed significantly between patients with generalized vitiligo and controls for both the polymorphisms in both populations. Allele frequencies significantly differed between patients with generalized vitiligo and controls for both the polymorphisms in the population from Gujarat. Interestingly, genotype and allele frequencies for -590 C/T single nucleotide polymorphism were significantly different between patients with localized vitiligo and controls in both the populations. The study revealed significantly increased IL4 mRNA, serum IL-4 and IgE levels in patients from Gujarat. Age of onset analysis of disease in patients suggested that the TTR2R2, TTR1R2 and CTR2R2 haplotypes had a profound effect in the early onset of the disease.

CONCLUSIONS

Our results suggest that these polymorphisms of the IL4 gene may be genetic risk factors for susceptibility towards vitiligo and the upregulation of the IL4 transcript, protein and IgE levels in individuals with susceptible haplotypes reveal the crucial role of IL-4 in the pathogenesis of vitiligo.

HLA alleles and amino-acid signatures of the peptide-binding pockets of HLA molecules in vitiligo

Vitiligo is a depigmenting disorder of the skin that is characterized by the loss of functional melanocytes from the lesional sites. Although the exact etiology is not understood, autoimmunity is thought to be a crucial deterministic factor. A recurring theme of several autoimmune disorders is the aberrant presentation of self-antigens to the immune system, which triggers downstream perturbations. Here we examine the role of alleles of HLA class I and class II loci to delineate vitiligo manifestation in two distinct populations. Our studies have identified three specific alleles, HLA-A*33:01, HLA-B*44:03, and HLA-DRB1*07:01, to be significantly increased in vitiligo patients as compared with controls in both the initial study on North Indians (N=1,404) and the replication study in Gujarat (N=355) cases, establishing their positive association with vitiligo. Both generalized and localized vitiligo have the same predisposing major histocompatibility complex alleles, i.e., B*44:03 and DRB1*07:01, in both the populations studied, beside the differences in the frequencies of other alleles, suggesting that localized vitiligo too may be an autoimmune disorder. Significant differences in the amino-acid signatures of the peptide-binding pockets of HLA-A and HLA-B α-chain and HLA-DR β-chain were observed between vitiligo patients and unaffected controls.

Targeting miRNAs for drug discovery: a new paradigm

The discovery of miRNAs and the establishment of it's clinical links with multiple diseases has led to a paradigm shift in the drug development pipeline of major pharmaceutical companies and has given birth to several biotechnology enterprises revolving around these magic molecules. The miRNA profiling studies over the last few years have indicated implicit involvement of miRNAs in the pathobiology of cancer, diabetes, infectious diseases as well as cardiovascular, neurological and immune system disorders. This information is currently being translated into tools for diagnosis, prognosis and predicting response to treatment. In addition, active and vigorous investigations are ongoing in several laboratories across academia and industry to decipher the precise molecular functions and mechanism of action for key miRNAs with therapeutic potential. Knowledge gained from these efforts will surely pave the way for designing effective R&D strategies and will revolutionize the way we diagnose and treat various diseases. The present review attempts to track the evolutionary progression of microRNA research from it's early infancy years to its maturity into a dynamic field of drug discovery.

The Eyes Absent phosphatase-transactivator proteins promote proliferation, transformation, migration, and invasion of tumor cells

The Eyes Absent (EYA) proteins combine transactivation, tyrosine phosphatase, and threonine phosphatase activities in their function as part of a conserved regulatory cascade involved in embryonic organ development. EYA tyrosine phosphatase activity contributes to fly eye development, and vertebrate EYA is involved in promoting DNA damage repair subsequent to genotoxic stress. EYAs are known to be expressed at elevated levels in ovarian and breast cancers. Here, we show that the tyrosine phosphatase activity of the EYAs promotes tumor cell migration, invasion, and transformation. These cellular effects are accompanied by alterations of the actin cytoskeleton and increased levels of active Rac and Cdc42. The invasiveness conferred by EYA is reflected in vivo by inhibition of metastasis seen when EYA3 expression is silenced in the invasive breast cancer cell line MDA-MB-231. Together, our data directly associate the tyrosine phosphatase activity of the EYAs with the oncogenesis-associated cellular properties of motility and invasiveness.

Mondor's disease of the penis associated with primary syphilis

A case of penile Mondor's disease associated with syphilitic chancre is reported. The aetiology and management of Mondor's disease is also discussed.

Isolation and characterization of a phorate degrading bacterium

AIMS

To study the degradation of phorate by a bacterium isolated from phorate-contaminated sites.

METHODS AND RESULTS

Ralstonia eutropha strain AAJ1 isolated from soil was found to degrade phorate (supplied as sole carbon source) upto 85% in 10 days in liquid medium. Half-life (t((1/2))) of phorate in the liquid medium in control (uninoculated) and in experimental (inoculated with R. eutropha, strain AAJ1) samples was recorded as 36.49 and 6.29 days, respectively. Kinetics revealed that phorate degradation depends on time and the reaction follows the first order kinetics. Diethyl dithiophosphate was one of the degradation products, which is markedly less toxic than the parent compound; other degradation products included phorate sulfoxide and phorate sulfone. Release of inorganic phosphates and sulfates indicated the potential of the isolate to further degrade the above-mentioned metabolites to simpler forms. The strain was also found to poses phosphomonoesterase and phosphodiesterase enzymatic activity, which are involved in biodegradation of organophosphorus compounds.

CONCLUSIONS

Ralstonia eutropha AAJ1 could degrade and detoxify phorate upto 85% in 10 days in laboratory conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

The isolate has the potential to be utilized for remediation of phorate-contaminated water and soil.

Phenotype frequencies of autosomal minor histocompatibility antigens display significant differences among populations

Minor histocompatibility (H) antigens are allogeneic target molecules having significant roles in alloimmune responses after human leukocyte antigen–matched solid organ and stem cell transplantation (SCT). Minor H antigens are instrumental in the processes of transplant rejection, graft-versus-host disease, and in the curative graft-versus-tumor effect of SCT. The latter characteristic enabled the current application of selected minor H antigens in clinical immunotherapeutic SCT protocols. No information exists on the global phenotypic distribution of the currently identified minor H antigens. Therefore, an estimation of their overall impact in human leukocyte antigen–matched solid organ and SCT in the major ethnic populations is still lacking. For the first time, a worldwide phenotype frequency analysis of ten autosomal minor H antigens was executed by 31 laboratories and comprised 2,685 randomly selected individuals from six major ethnic populations. Significant differences in minor H antigen frequencies were observed between the ethnic populations, some of which appeared to be geographically correlated.

Peptides from cellular proteins evoking alloimmune responses in human leukocyte antigen–identical transplantation are called minor histocompatibility (H) antigens. Upon hematopoietic stem cell transplantation (HSCT) for hematological malignancies or for solid tumors, responses to minor H antigens may have detrimental effects, e.g., graft-versus-host-disease and graft rejection, but can also significantly contribute to the eradication of the tumor cells. We designated the latter antigens as “tumor” minor H antigens. Current clinical trials aim at using these tumor minor H antigens to boost the graft-versus-tumor response. So far, it is unclear how frequently the HSCT recipient and donor differ in their minor H antigens and thus how many cancer patients are eligible for minor H antigen-based treatment. Therefore, worldwide 31 laboratories joined forces to determine the genotype and phenotype frequencies of ten autosomally encoded minor H antigens in six ethnic populations. The frequencies vary depending upon ethnic background and geographic location of the population, implying that the potential applicability of the tumor minor H antigens differs from one population to another. Depending on the population, the current theoretical percentages of clinical application of the eight tumor minor H antigens in HLA-matched combinations is estimated at 12% to 34%.

Molecular diversity of HLA-A, -B and -C alleles in a North Indian population as determined by PCR-SSOP

We have used molecular methods to determine the frequencies of human leukocyte antigen (HLA)-A, -B and -C alleles in normal, healthy, unrelated individuals from North India using polymerase chain reaction and hybridization with sequence-specific oligonucleotide probes as there is no comprehensive report showing molecular diversity of all the class-I alleles present in North Indians. A*0101, A*0206, A*0301, A*1101, A*6801, A*2401 and A*3101 were the most prevalent alleles of the A locus with 91.11% of the samples showing heterozygosity. At the HLA-B locus a total of 47 B locus alleles were observed and the only allele found with an allele frequency of 15% was B*5801. Other frequent B-locus alleles observed were B*5101, B*3503 and B*4006 with relatively less frequent alleles like B*5201, B*3501, B*0702, B*4403, B*5701, B*1801 and B*5501. Of the samples studied 92.31% were heterozygous for B-locus alleles. Cw*0602 and Cw*0401 were the most frequent C-locus alleles. Other frequent C-locus alleles were Cw*0102, Cw*0302, Cw*0701, Cw*0702, Cw*1202, Cw*1203, Cw*1502 and Cw*1503. HLA alleles common in Africans like B*5801, A*68012, B*5301, B*44032, B*4006 and Cw*1701 were observed in the North Indians besides oriental alleles like B*1301, B*1502 and B*4001 confirming that the genetic make-up of North Indians is Caucasoid with elements of Mongoloid and Negrito races. Some new/rare alleles like B*1802, described as a new allele from Thailand and B*8101, described earlier in a Bubi population were also observed although with low frequencies, showing the diversity of HLA class-I alleles present in the North Indians.

Association and interaction of the TNF-alpha gene with other pro- and anti-inflammatory cytokine genes and HLA genes in patients with type 1 diabetes from North India

Type 1 diabetes (T1D) is a multifactorial autoimmune disorder where major histocompatibility complex (MHC) genes and the insulin-linked polymorphic region have been shown to play major roles. We report here an integrated effect of tumor necrosis factor (TNF) alpha with other cytokine genes. The TNF-alpha-308 GA and AA (high secretor) polymorphisms were significantly increased in the patients with T1D (n = 235) [P < 7 x 10(-6), odds ratio (OR) = 3.04, 95% confidence interval (CI) = 1.8-5.3] compared with the controls (n= 128). The variants of interferon-gamma (IFN-gamma) (A(+874)T), interleukin (IL)-6 (G(-174)C), IL-10 (A(-1082)G, T(-819)C, C(-592)A) and transforming growth factor (TGF) beta1 (T(cdn10)C, G(cdn25)C) did not show a significant difference between patients and controls. However, simultaneous presence of TNF-alpha-308 GA+AA along with both high and low secretor genotypes of IFN-gamma (P < 0.003) was significantly increased in patients. Simultaneous presence of TNF-alpha-308 GA + AA along with high secretor genotypes of IL-6 (P < 0.0001, OR = 2.61, 95% CI = 1.5-4.56), IL-10 (P < 0.0001, OR = 4.26, 95% CI = 1.9-10.1) and TGF-beta1 (P < 0.00004, OR = 2.8, 95% CI = 1.6-4.86) was also significantly increased in patients with T1D. Low secretor genotype of TNF-alpha-308 GG along with low secretor genotypes of IFN-gamma (P < 0.001, OR = 0.465, 95% CI = 0.28-0.77), high secretor genotypes of IL-6 (P < 0.000004, OR = 0.76, 95% CI = 0.227-0.621) and TGF-beta1 (P < 0.000006, OR = 0.336, 95% CI = 0.198-0.568) was protective. The TNF-alpha-308 G allele was in linkage disequilibrium (LD) with the human leukocyte antigen (HLA)-B*0801-DRB1*0301 haplotype, while TNF-alpha-308 A allele was in LD with the HLA-B*5001-DRB1*0301 and B*5801-DRB1*0301 haplotypes, suggesting that the effect of TNF-alpha -308 A allele is not because of its being in LD with any HLA alleles, but because of its functional role and its integrated effect with other cytokines.

Decrease in CD4+ T lymphocyte proliferation responses and enhanced CD150 cell expression in health care workers non-responsive to HBV vaccine

The non-response to hepatitis B vaccine in health care workers (HCWs) is reported to vary between 5 and 40%. The underlying cellular and molecular events for unresponsiveness to HBV vaccine have not yet been characterized at any great extent. In the current study, we examined the CD150 surface expression levels and its association with polyclonally activated and HBV specific stimulated cellular proliferations in responders and non-responders. CD150 was identified as upregulated expression marker with suppressive regulatory cell function on all activated T cells by gene chip analysis. We found the overall weak cellular proliferation in response to specific and non-specific agents in non-responders. This is significantly associated with enhanced surface expression of CD150 in the non-responders. A strong expression of CD150 with weak cellular proliferation could be used as a predictive marker for non-responsiveness.

Polymorphisms at +49A/G and CT60 sites in the 3' UTR of the CTLA-4 gene and APECED-related AIRE gene mutations analysis in sporadic idiopathic hypoparathyroidism

Autoimmune diseases such as Graves' disease and type 1 diabetes have been linked with +49A/G and CT60 single nucleotide polymorphisms (SNPs) in the 3' UTR of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene. Both these SNPs are functionally relevant and linked with T-lymphocyte activation. Hypoparathyroidism is seen in 70% of patients with autoimmune polyendocrinopathy candidiasis ectodermal dystrophy syndrome (APECED). Although calcium sensing receptor autoantibodies (CaSRAb) and generalized activation of T lymphocytes are reported among patients with sporadic idiopathic hypoparathyroidism (SIH), CTLA-4 gene SNPs and APECED-related autoimmune regulator (AIRE) gene mutations have not been assessed in them. We studied lead CTLA-4 gene SNPs and APECED-related AIRE gene mutations in 73 patients with SIH and 114 healthy subjects. The CTLA-4 gene SNPs +49A/G in exon 1, CT60A/G in 3' UTR and -318C/T in the promoter region were genotyped by polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) using BstEII, NcoI and MseI endonucleases, respectively. The APECED-related AIRE gene mutations, which is R257X (Finn-major) in exon 6, 4-bp insertion and 13-bp deletion in exon 8, and Iranian Jews population 'Y85C' mutation in exon 2, were studied by PCR-RFLP (Taq-I), PCR and nucleotide sequencing, respectively. CaSRAb were studied by immunoblotting. The frequencies of CTLA-4 A/A(49), A/G(49) and G/G(49) genotypes in the patients (47.9%, 38.4% and 13.7%) and controls (45.6%, 39.5% and 14.9%, respectively) and the frequencies of CT60 A/A, A/G, and G/G genotypes in the patient (42.4%, 37.0% and 20.6%) and the control (38.6%, 40.4% and 21.0%, respectively) groups were not significantly different. The frequencies of various haplotypes including genetic loci +49A/G and CT60 and frequencies of G alleles at these positions were comparable between patient and the control groups and its presence did not correlate with clinical and biochemical indices of the disease. None of the patients had APECED-related AIRE gene mutations. Lack of significant difference in the pattern of CTLA-4 A/G(49) and/or CT60A/G genotypes and absence of common APECED syndrome-related AIRE gene mutations among patients and controls suggest that these sites do not play a role in the development of the SIH.

Immunoprophylactic effects of the anti-leprosy Mw vaccine in household contacts of leprosy patients: clinical field trials with a follow up of 8-10 years

We report here a large scale, double blind immunoprophylactic trial of a leprosy vaccine based on Mycobacterium w (Mw) in an endemic area of Kanpur Dehat, Uttar Pradesh, India. A population of 420,823 spread over 272 villages was screened where 1226 multibacillary (MB) and 3757 paucibacillary (PB) cases of leprosy were detected. A total of 29,420 household contacts (HHC) of these patients were screened for evidence of active or inactive leprosy. After exclusion of 1622 contacts for any of the different exclusion criteria, a total of 24,060 HHC could be vaccinated for vaccine or placebo under coding (20,194 administered two doses and 3866 received single dose). The vaccine consisted of 1 x 10(9) heat killed bacilli (Mw) in normal saline for the first dose and half of the first dose, i.e. 5 x 10(8) bacilli for the second dose, given 6 months after the first dose. The placebo consisted of 1/8th dose of the normal dose of tetanous toxoid. Both placebo and vaccine were given under double-blind coding, The contacts were followed up during three surveys at 3, 6 and 9 years after the initial vaccination, for detection of post-vaccination cases (PVCs) and observing any side-effects caused as a result of vaccination. The codes were opened on 24th January 2001, after the analysis of the data following completion of the third and final follow-up survey. When only contacts received the vaccine, Mw vaccine showed a protective efficacy (PE) of 68-6% at the end of first, 59% at the end of the second and 39.3% at the end of the third follow-up survey. When both patients and contacts received the vaccine, the protective efficacy observed was 68%, 60% and 28% at the end of the first, second and third surveys, respectively. When patients, and not the contacts, received the vaccine, a PE of 42.9% in the first, 31% in the second and 3% in the third survey was shown. These results suggest that the vaccination of the contacts is more valuable in achieving the objective of immunoprophylaxis than that of patients, and the vaccine effects are noted maximally in children (as compared to adolescents and adults) who constitute the most responsive group The effect of vaccine is sustained for a period of about 7-8 years, following which there is a need to provide a booster vaccination for the sustained protection.

Molecular basis of predisposition to develop type 1 diabetes mellitus in North Indians

Type 1 diabetes (T1D) mellitus is a multifactorial autoimmune disease where more than 90% of insulin-producing pancreatic beta cells are destroyed before the clinical manifestations, warranting a need to identify the children predisposed to get the disease. Of the 20 genomic intervals implicated for the risk to develop T1D, the major histocompatibility complex (MHC) region on chromosome 6p21.31 (IDDM1) has been the major contributor, followed by 5' regulatory region of the insulin (INS) gene on chromosome 11p15.5 (IDDM2). MHC has a role in antigen presentation and IDDM2 has been shown to have a role in transcription of insulin in the thymus. Hence, alleles of human leukocyte antigen (HLA)-DRB1, DQB1, and insulin-linked variable number of tandem repeats (INS-VNTR) were studied in 110 T1D patients and 112 healthy controls using polymerase chain reaction and hybridization with sequence-specific oligonucleotide probes (PCR-SSOP) and PCR restriction fragment length polymorphism (PCR-RFLP), respectively. HLA-DRB1*0301 was significantly increased in the T1D patients along with associated DQB1*0201 followed by DRB1*0401 and DRB1*0405. DRB1*0701 was observed to be the most protective allele followed by DRB1*0403 and DRB1*0404. Although DQB1*0302 which is associated with both the protective and susceptible DR4 alleles was not significantly increased, heterozygous DQB1*0201, *0302 was significantly increased in the TID patients. Because INS-VNTR class I homozygosity was also significantly increased in the patients, simultaneous presence of DRB1*0301 along with homozygous INS-VNTR class I, gave a relative risk (RR) of 70.81. However, a similar analysis of DQB1*0201 and *0302 along with INS-VNTR alleles did not give such high RRs. Thus, the two independently assorting alleles at two loci i.e., DRB1*0301 and INS-VNTR class I, on two different chromosomes may have the potential to predict a prediabetic in North India.

Parathyroid hormone gene polymorphism and sporadic idiopathic hypoparathyroidism

The pathogenetic mechanisms involved in the development of sporadic idiopathic hypoparathyroidism are currently under investigation. Although autoantibodies against the calcium-sensing receptor (CaSR) have been implicated to play a role, these could be demonstrated in only 49% of a group of 51 patients with sporadic idiopathic hypoparathyroidism that we previously studied. Therefore, we investigated 49 of these patients further, regardless of their antibody status, and looked for mutations in the section of the PTH gene sequence that coded for prepro-PTH as well as the 3'-untranslated region (3'-UTR) of the gene, which is believed to be involved in the stability of its mRNA. We also examined the relationship between the clinical manifestations of the disease and the occurrences of two commonly observed single nucleotide polymorphisms (SNPs) in the PTH gene. In 49 of the patients with idiopathic hypoparathyroidism and in 55 healthy controls, the SNPs were characterized by restriction analysis using DraII and BstBI enzymes. In a subset of these patients, exons 2 and 3 of the PTH gene (n = 37) and its 3'-UTR region (n = 40) were also sequenced. No mutations were observed in the segment of the PTH gene coding for the signal peptide, prohormone, or the 3'-UTR region. However, three well described SNPs were observed: 1) an A-->G substitution in intron 1 in 35.1% of the patients; 2) a G-->A substitution in intron 2, characterized by BstBI, in one or both alleles in 27%; and 3) a C-->A substitution at codon 52 (CGA) of exon 3, characterized by DraII, in one or both alleles in 59.7% of the patients. There was no significant difference in the frequency of occurrence of these SNPs between the patient and the control groups. Furthermore, the mean age at onset of symptoms, body mass index, frequency of cataract, tetany, convulsion, basal ganglia calcification, serum calcium, inorganic phosphorus, and intact PTH were not significantly different between patients with and without the above-described SNPs. Thus, the data from this report demonstrate that in patients with sporadic idiopathic hypoparathyroidism, neither the clinical manifestations nor the biochemical indexes of the disease are related to the occurrence of mutations or SNPs in the PTH gene. Because neither patient nor control samples exhibited any variations in the sequence of their 3'-UTR regions, it is unlikely that mRNA instability is a factor in the pathogenesis of the disease. Additional studies are required to investigate the role of other genes and autoantigens that may be involved in the genesis of idiopathic hypoparathyroidism.

Prevalence of calcium sensing receptor autoantibodies in patients with sporadic idiopathic hypoparathyroidism

OBJECTIVE

The pathogenesis of sporadic idiopathic hypoparathyroidism is unclear. The calcium sensing receptor (CaSR) plays a pivotal role in extracellular calcium homeostasis and is the candidate autoantigen in hypoparathyroidism associated with autoimmune polyglandular endocrinopathy syndrome. We therefore looked for antibodies (Ab) against the CaSR in patients with sporadic idiopathic hypoparathyroidism and their association, if any, with the major histocompatibility complex (MHC) class II human leukocyte antigen (HLA)-DR haplotypes.

METHODS

The subjects included 51 patients with sporadic idiopathic hypoparathyroidism and 45 healthy controls. Investigations included computerised tomography, serum calcium, phosphorus, thyroxine, TSH, cortisol, intact parathyroid hormone (iPTH), ACTH and thyroid peroxidase (TPO) and adrenal antibodies. The CaSRAb were assayed in patients' sera by Western blot. Genotyping of the HLA-DR locus was performed using PCR and sequence-specific oligonucleotide probes.

RESULTS

Intracranial calcification and cataract were present in 76.5% and 41.1% of the patients respectively and 62.7% had convulsions. Autoantibodies against the 168 kDa CaSR protein were demonstrated in the serum of 49.0% of the patients and in 13.3% of the controls (P<0.001). Pre-incubating serum samples from the CaSRAb-positive patients with parathyroid membrane produced a 90% decrease in the band intensity. HLA-DRB1*01 and DRB1*09 alleles were significantly associated with idiopathic hypoparathyroidism (relative risk of 7.8, P=0.001). The frequency of HLA-DRB1*09 and DRB1*10 alleles tended to be higher in patients positive for the CaSRAb. There was no significant difference in the frequency of occurrence of convulsions, cataract, intracranial calcification, calcium:phosphorus ratio, and iPTH levels between patients with and without CaSRAb.

CONCLUSION

49.0% of the patients studied had serological evidence of organ-specific autoimmunity against the CaSR protein. The occurrence of CaSRAb and the HLA-DR associations imply an autoimmune component to the disease, but the primary role of the CaSRAb in the pathogenesis of the disease needs to be assessed further.

Changing trends of Candida species in neonatal septicaemia in a tertiary North Indian hospital

Four hundred and fifty four blood samples of clinically diagnosed septicemic neonates were collected over a period of six months from the neonatal ICU of Kalawati Saran Children Hospital, New Delhi. 144 samples were culture positive; out of which 50 (34.7%) were Candida isolates. 92% isolates were Candida tropicalis, 4% were C. albicans and C. kefyr each. The study emphasises the changing pattern of Candida species and their importance in blood stream infections in neonates.

Receptor-Ck regulates giardia encystation process

The study addressed to resolve the mechanism involved in cholesterol-dependent regulation of giardia encystation process, revealed that (a) the trophozoites have the ability to express genes coding for receptor-Ck and sterol element binding protein (SREBP); (b) inhibition of cholesterol dependent activation of receptor-Ck results in the upregulation of CWP-1 gene expression leading to encystation process. Based upon these findings, we propose that receptor-Ck dependent signalling is responsible for the regulation of giardia encystation process by cholesterol.

Induction of thymidine kinase in mouse skin exposed to 12-O-tetradecanoylphorbol-13-acetate

Topical application of 12-O-tetradecanoylphorbol-13-acetate (TPA) exhibited an increase in the epidermal thymidine kinase (TK) activity in a dose dependent manner. Maximum induction of TK was observed at a TPA concentration of 2.5 microg per animal. The induction of TK by TPA appeared to be a function of time with the maximum TK induction between 4 and 16 h after TPA application. Repeated applications of TPA every 24 h did not show any cumulative effect rather TK activity appeared to be normal after two applications. However, repeated applications of TPA at an interval of 48 h exhibited increased TK activity even after 16 applications. Cycloheximide and actinomycin D, the inhibitors of protein and RNA synthesis, inhibited the TPA induced activation of TK. Our results demonstrated that TPA induced the TK activity may be, by increasing de novo synthesis of enzyme protein and this induction might lead to increased de novo DNA synthesis after TPA application. DMBA was used as a reference compound. As far as the authors are aware, this is the first report on TK induction by topical application of TPA.

In vitro propagation of Withania somnifera and isolation of withanolides with immunosuppressive activity

Withania somnifera plantlets were produced in vitro from the shoot-tip of aseptically germinated seedlings. Culture conditions were optimized using different plant growth regulators which gave rise to 120 shoots from a single bud. The plantlets were then transferred to pots and maintained in greenhouse for 4 months. 90% of these in vitro propagated plantlets survived and showed normal growth. Leaves from these plants were used for isolation of the withanolides. Methanolic extract of leaves from plantlets growing in tissue culture and those transferred to the greenhouse were evaluated for immunomodulatory activity. While the extract from greenhouse samples showed potent immunosuppressive activity, those from tissue cultures samples did not show any activity. Fractionation and characterization of withanolides, using HPLC, NMR, MS methods revealed the presence of withaferin A in the greenhouse samples. Our results indicate that Withania species may require longer time and better differentiation and also natural environment for the production of withaferin A.

Mycobacterium w vaccine, a useful adjuvant to multidrug therapy in multibacillary leprosy: a report on hospital based immunotherapeutic clinical trials with a follow-up of 1-7 years after treatment

A vaccine based on autoclaved Mycobacterium w was administered, in addition to standard multidrug therapy (MDT), to 156 bacteriologically positive, lepromin negative multibacillary leprosy patients compared to a well matched control group of 145 patients with a similar type of disease who received a placebo injection in addition to MDT. The MDT was given for a minimum period of 2 years and continued until skin smear negativity, while the vaccine was given at 3-month intervals up to a maximum of eight doses. The fall in clinical scores and bacteriological indices was significantly more rapid in vaccinated patients, from 6 months onward until years 2 or 3 of therapy. However, no difference was observed in the fall in bacteriological index in the two groups from year 4 onwards. The number of LL and BL patients released from therapy (RFT) following attainment of skin smear negativity, after 24-29 months of treatment was 84/133 (63.1%) in vaccinated and 30/120 (25.0%) in the placebo group; the difference was highly statistically significant (P < 0.0001). In all, 90.2% patients (146/162) converted from lepromin negativity to positivity in the vaccine group, as against 37.9% (56/148) in the placebo group. The average duration of lepromin positivity maintained following eight doses of vaccine administered over 2 years was 3.016 years in the vaccine and 0.920 years in the placebo group. Histological upgrading after 2 years of treatment in the LL type was observed in 34/84 (40.5%) cases in the vaccine and 5/85 (5.9%) cases in the placebo group, the difference being statistically significant (P < 0.001). The incidence of type 1 reactions was significantly higher (30.5%) in the vaccine group than (19.7%) in the placebo group (P = 0.0413); the difference was mainly observed in LL type (P = 0.009). The incidence of type 2 reactions was similar (31.8 and 34.6%) in vaccine and placebo groups. The vaccine did not precipitate neuritis or impairments over and above that encountered with MDT alone. After 5 years of follow-up following RFT, no incidence of bacteriological or clinical relapses was observed in both groups.

Reactional states and neuritis in multibacillary leprosy patients following MDT with/without immunotherapy with Mycobacterium w antileprosy vaccine

A vaccine based on autoclaved Mycobacterium w was administered, in addition to standard multidrug therapy (MDT), to 157 untreated, bacteriologically positive, lepromin negative multibacillary leprosy patients, supported by a well matched control group of 147 patients with similar type of disease, who received a placebo injection in addition to MDT. The MDT was given for a minimum period of 2 years and continued until skin smear negativity, while the vaccine/placebo was given at 3-monthly intervals up to a maximum of eight doses. The incidence of type 2 reaction and neuritis during treatment and follow-up showed no statistically significant difference in the vaccine and placebo groups. The incidence of type 1 reaction (mild in most cases), however, was higher in the vaccine group (P = 0.041, relative risk ratio 1.79), considering LL, BL and BB leprosy types together, and considerably higher (P = 0.009) in LL type, probably because of confounding due to higher number of patients with previous history of reaction in this group. The occurrence of reactions and neuritis in terms of single or multiple episodes was similar in the vaccine and placebo groups. The association of neuritis and reactions, as well as their timing of occurrence (during MDT or follow-up), was also similar in the two groups, with more than 90% of occurrences taking place during MDT. The incidence of reversal reaction was significantly higher among the males in the vaccine group (34.5% versus 8.3%, P = 0.019). Patients with high initial BI (4.1-6.0) showed higher incidence of reactions (70.3%) as compared to those with medium (2.1-4.0) and low (0.3-2.0) BI where the reactions were observed with a frequency of 56.1% and 38.8%, respectively. However, unlike reactions, neuritis incidence did not seem to be affected by initial BI to the same extent in the vaccine group, with frequencies of 35.3%, 36.3% and 25.9% in the three mentioned BI ranges. Overall, the vaccine did not precipitate reactional states and neuritis over and above that observed with MDT alone.

Anti-keratin antibodies in patients with rheumatoid arthritis

As the proportion of patients with rheumatoid arthritis (RA) who have anti-keratin antibodies (AKA) varies in different ethnic groups, we studied its occurrence in a hospital populations with RA and its association with different disease variables. Sera from 84 consecutive patients with RA, 100 healthy controls and 85 disease controls (polyarticular juvenile rheumatoid arthritis, systemic lupus erythematosus, ankylosing spondylitis) were tested for AKA by an indirect immunofluorescence assay that used rat esophagus as substrate. The proportion of patients with RA who had AKA (47/84) was higher than in healthy controls (2/100; P < 0.001) and in disease controls (2/85; P < 0.001). The frequency of AKA positivity was higher among patients who had severe disease (P < 0.05) and rheumatoid factor. Anti-keratin antibody is present in 56 per cent of our patients with RA and is associated with severe disease.

Effect of nicotinamide on 12-O-tetradecanoyl-phorbol-13-acetate exposed mouse skin endonuclease activity and DNA synthesis

Nicotinamide (NA), a relatively nontoxic compound, has been shown to inhibit tumor development, induce differentiation, increase the sensitization of the anticancer drug resistant cancer cells and is being used in different skin ailments. But there are not many reports on its mechanism of action. Here we report that NA induced endonuclease activity. This endonuclease induction by NA appeared to be dose dependent and a function of time. As evident by the use of modifiers of DNase I, this endonuclease appeared to be like DNase type I. Increased [3H] thymidine incorporation in DNA in the presence of NA is possibly a consequence of increased 3-OH' nicks due to increased DNA fragmentation by increased endonuclease activity. The present results would be of help in the better understanding of the mechanism of NA action and its improved use in cancer control.

Induction of lepromin positivity and immunoprophylaxis in household contacts of multibacillary leprosy patients: a pilot study with a candidate vaccine, Mycobacterium w

We screened 487 household contacts of multibacillary (MB) patients for evidence of disease and their lepromin status. From the 444 results available, 302 (68.02%) were lepromin positive and 142 (31.98%) were lepromin negative on initial testing. The initial lepromin status as assessed in the group of 54 contacts having disease at the outset showed 24 out of 46 (52.2%) to be lepromin positive and 22 of 46 (47.8%) to be lepromin negative. In the same group, among 24 lepromin positives, 22 (91.7%) had paucibacillary (PB) and 2 (8.3%) had multibacillary (MB) disease; among the lepromin negatives, 12 (54.5%) had PB and 10 (45.5%) had MB disease. Out of 72 initially lepromin-negative contacts administered Mycobacterium w vaccine and followed up, the cumulative percentages show that 53 (73.6%) converted to positivity after a single dose, 10 (87.5%) after a second dose and 67 (93.1%) after the third dose. The incidence of new cases with leprosy was 8 out of 231 (3.46%) among lepromin-positive contacts and 5 out of 93 (5.38%) among lepromin-negative contacts administered Mycobacterium w vaccine. Among 231 lepromin-positive contacts, the new cases occurred in those with a 1+ and 2+ lepromin response only, and no case occurred among 51 contacts with a 3+ lepromin response. The incidence among lepromin-positive contacts in this study (3.46%) was similar to the observations in two other studies: 3.2% by Dharmendra, et al. and 6.9% by Chaudhary, et al. However, the incidence among lepromin-negative contacts administered Mycobacterium w vaccine was significantly lower than that observed among lepromin-negative contacts not administered any vaccination in the other two studies (14.1% by Dharmendra, et al. and 29.0% by Chaudhary, et al.). To conclude, although a study of small sample size, the preliminary evaluation indicates that administration of Mycobacterium w vaccine seems to have the potential to reduce the incidence of leprosy among household contacts of leprosy patients. More explicit results about the vaccine will be available from the ongoing field trials in Kanpur Dehat in the near future.