Detection of human perforin by ELISpot and ELISA: ex vivo identification of virus-specific cells

The perforin (PFN) protein is essential for the elimination of target cells by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. The study of cells releasing PFN has been hampered by a lack of sensitive methods. We therefore produced PFN-reactive monoclonal antibodies (mAb) and developed capture enzyme-linked immunosorbent (ELISA) and enzyme-linked immunospot (ELISpot) assays. Three mAbs were generated and shown to react with unique determinants of PFN. All mAbs recognized intracellular PFN in human peripheral blood mononuclear cell (PBMC) as assessed by flow cytometry and immunohistochemistry. Functional PFN capture ELISA and ELISpot assays were developed utilizing two of the mAbs for capture and the third mAb for detection. When examining PFN release by the YT lymphoma cell line, the ELISpot displayed a greater detection sensitivity than the ELISA. Assessment of PFN release by a CTL clone using ELISpot gave results consistent with a parallel (51)Cr-release cytotoxicity assay. Moreover, PFN release by PBMC could be quantified by ELISpot and ELISA after ex vivo stimulation with defined CTL epitopes from common viruses. These novel immunoassays will be valuable for further investigations of the mechanisms underlying granule-mediated apoptosis. In addition, the capture immunoassays could provide tools for studying CTL responses in infectious and tumor diseases as well as for vaccine development.     

A comparison of the tolerability of two dilution volumes (0.5 mL and 1.0 mL) of a purified chick embryo cell rabies vaccine administered intramuscularly to healthy adult volunteers: A randomized, intraindividual, assessor-blind study

Background: The current recommendation of the manufacturer for administering purified chick embryo cell rabies vaccine (PCECV) is to reconstitute the contents with 1.0 mL of water for injection (WFI). However, it has been debated whether a lower volume of WFI (0.5 mL) is likely to cause less pain.Objectives: The aims of this study were to compare the tolerability of PCECV administered IM at a volume of 0.5 mL versus 1.0 mL of diluent and to determine the immunogenicity of the vaccine when administered according to the World Health Organization-recommended preexposure prophylaxis regimen for rabies immunization.Methods: This comparative, intraindividual, assessor-blind study was conducted at the Department of Clinical Pharmacology, Topiwala National Medical College and Bai Yamunabai Laxman Nair Charitable Hospital Mumbai, India). Healthy volunteers aged 18 to 50 years received, by randomized sequence, 3 IM injections of PCECV, diluted in 0.5 mL or 1.0 mL of WFI, on study days 0, 7, and 28. Tolerability was assessed at 30 minutes and 24 hours after injection and included assessments for local and systemic reactions. For immunogenicity assessment, rabies virus-neutralizing antibody 0RVNA) titers were assayed at baseline and on day 49 (ie, 3 weeks after the third injection).Results: Twenty-six subjects (24 men, 2 women; mean [SD] age, 22.4 [2.4] years; mean [SD] body weight, 59.0 [11.3] kg) entered the study. Twenty-five subjects were included in the tolerability assessment; 24 in the immunogenicity assessment. No statistically significant differences were found between dilutions in the frequency of local and systemic reactions. Most reactions were mild. All subjects developed RVNA titers >0.5 IU/mL (indicative of protection) by day 49.Conclusions: In this population of healthy volunteers, a full antigenic dose of PCECV in a dilution of 0.5 mL WFI is as well tolerated locally and systemically as in a dilution of 1.0 mL. All subjects developed levels of RVNA far exceeding 0.5 IU/mL, which is indicative of protection against rabies.     

Expression of Fas and Fas ligand in Hodgkin's disease.

Fas and Fas ligand expression were investigated in twenty two cases of classical Hodgkin's disease (HD) by immunohistochemistry. While Reed-Sternberg (RS) cells in 7/22 (32%) cases expressed Fas ligand, reactive lymphoid cells expressed Fas ligand in only 2 (9%) cases. In 20/22 (91%) cases, the RS cells expressed Fas. A higher proportion of RS cells in the nodular sclerosis subtype expressed Fas as compared to the mixed cellularity subtype. In 18/22 (82%) cases, Fas expression was also noted in the reactive lymphoid cells. In eight cases, the reactive lymphoid cells were also analyzed by flow cytometry and a majority of them were CD4+CD45RO+. Most of these activated T-cells expressed Fas but were negative for Fas Ligand. To investigate the co-expression of Fas and Fas Ligand in the RS cells, six cases were subjected to Fas and Fas ligand immunostaining on consecutive sections. The co-expression was documented in the RS cells in four of six cases. These six cases with expression of both Fas and Fas ligand were investigated for the incidence of apoptosis. There was no statistically significant relationship between expression of Fas on reactive cells, expression of FasL on RS cells and the proportion of apoptotic reactive cells. In all these cases apoptosis was not observed in the RS cells. Thus Fas - FasL interactions may not lead to apoptosis of the RS cells.     

Regression of grade III astrocytoma during the treatment of CML with imatinib mesylate

Astrocytomas are central nervous system neoplasms, which are derived predominately from astrocytes. On the basis of the histopathologic characteristics astrocytomas are graded from I to IV. The cells that demonstrate the greatest degree of anaplasia are used to determine the histologic grade of the tumor. The mean age of survival are approximately 10 years from the time of diagnosis for pilocystic astrocytomas (World Health Organization grade I), more than 5 years for patients with low-grade diffuse astrocytomas (WHO grade II), 2 to 5 years for those with anaplastic astrocytomas (WHO grade III), and less than 1 year for patients with glioblastoma (WHO grade IV). The treatment is a combination of surgery, radiation, and chemotherapy depending of the grade of astrocytoma. We present a case of 31-year-old man with grade III astrocytoma with subsequent chronic myelogenous leukemia treated with imatinib mesylate as part of his chronic myelogenous leukemia treatment failing to show recurrence of the astrocytoma 10 years after standard treatment for astrocytoma.     

Synthesis and biological evaluation of novel azetidine derivatives as dopamine antagonist

In this study, azetidine derivatives were evaluated for their potency as dopaminergic antagonist. The study comprised derivatives substituted in 3-position with amide moiety. Further, the phenyl moiety of amide was modified at 2, 3, or 4-position. The substituted compounds were biologically evaluated for their affinity for D₂ and D₄ receptors. The most potent D₂ and D₄ antagonist among these compounds appeared to be the N-(1-benzhydryl-azetidin-3yl)-2-bromo-benzamide and N-(1-benzhydryl-azetidin-3yl)-4-bromo-benzamide, respectively. Various docking interactions of CPPMA with the D₄ receptor and the same for compound 5 i.e., N-(1-benzhydryl-azetidin-3yl)-4-bromo-benzamide were found to have good correlation with observed biological activity.     

En Bloc Excision of Phyllodes Tumor of the Breast: Radical Approach Heralds Better Outcome

IntroductionSurgery is the primary treatment of phyllodes tumor of the breast, and margins are the most important risk factor associated with local recurrence. We conducted a retrospective audit of 433 patients treated at our center.Patients and MethodsWomen who presented with phyllodes tumors between 1999 and 2017 were included in the analysis. Data was collected from the hospital medical records, telephonic interviews, and electronic mail.ResultsOf the 433 women included in this study, 177 (40.9%) had benign phyllodes tumors, 84 (19.4%) were borderline, 131 (30.3%) were malignant, and 41 (9.5%) had sarcoma. A history of previous excision was noted in 154 (35.6%) patients, of which 104 presented with local recurrence. Of the total patients, 209 (48.3%) underwent breast conservation surgery; the median pT was 6 cm. At a median follow-up of 37.9 months, the 5-year disease-free survival (DFS) was 82.9%. On multivariate analysis, the factors that impacted DFS were histology (hazard ratio, 4.1; 95% confidence interval [CI], 1.5-10.9; P = .005) and history of previous excision biopsy (hazard ratio, 3.39; 95% CI, 1.76-6.52; P < .001). We analyzed 231 women who presented without any prior excision separately, wherein at a median follow-up of 44.1 months, the DFS was 92.1% (95% CI, 92.05%-92.15%). In addition, less recurrences were noted in this cohort (5.6% [13/231] in no-excision biopsy vs. 12.5% with surgery done prior to presentation to our institute).ConclusionA previous history of excision and the histologic subtype of phyllodes tumor are factors that have an impact on DFS, thus emphasizing the need for appropriate surgical planning and en bloc excision of the phyllodes at presentation.