Purinoreceptors and ectonucleotidases control ATP-induced calcium waveforms and calcium-dependent responses in microglia: Roles of P2 receptors and CD39 in ATP-stimulated microglia

Adenosine triphosphate (ATP) and its metabolites drive microglia migration and cytokine production by activating P2X- and P2Y- class purinergic receptors. Purinergic receptor activation gives rise to diverse intracellular calcium (Ca2+ signals, or waveforms, that differ in amplitude, duration, and frequency. Whether and how these characteristics of diverse waveforms influence microglia function is not well-established. We developed a computational model trained with data from published primary murine microglia studies. We simulate how purinoreceptors influence Ca2+ signaling and migration, as well as, how purinoreceptor expression modifies these processes. Our simulation confirmed that P2 receptors encode the amplitude and duration of the ATP-induced Ca2+ waveforms. Our simulations also implicate CD39, an ectonucleotidase that rapidly degrades ATP, as a regulator of purinergic receptor-induced Ca2+ responses. Namely, it was necessary to account for CD39 metabolism of ATP to align the model's predicted purinoreceptor responses with published experimental data. In addition, our modeling results indicate that small Ca2+ transients accompany migration, while large and sustained transients are needed for cytokine responses. Lastly, as a proof-of-principal, we predict Ca2+ transients and cell membrane displacements in a BV2 microglia cell line using published P2 receptor mRNA data to illustrate how our computer model may be extrapolated to other microglia subtypes. These findings provide important insights into how differences in purinergic receptor expression influence microglial responses to ATP.

Safety and immunogenicity of an indigenously developed tetanus toxoid, diphtheria toxoid, and acellular pertussis vaccine (Tdap) in adults, adolescents, and children in India

BACKGROUND

This study assessed safety and immunogenicity of Serum Institute of India Pvt Ltd (SIIPL)'s tetanus toxoid (TT), diphtheria toxoid (DT), and acellular pertussis booster vaccine (Tdap).

RESEARCH DESIGN AND METHODS

In this Phase II/III, multicenter, randomized, active-controlled, open-label study, 1500 healthy individuals, aged 4-65 years, were randomized to receive a single dose of SIIPL Tdap or comparator Tdap vaccine (Boostrix®; GlaxoSmithKlines, India). Adverse events (AEs) during initial 30 minutes, 7-day, 30-day post-vaccination were assessed. Blood samples were taken before and 30 days post-vaccination for immunogenicity assessment.

RESULTS

No significant differences in incidence of local and systemic solicited AEs were observed between the two groups; no vaccine-related serious AEs were reported. SIIPL Tdap was non-inferior to comparator Tdap in achieving booster responses to TT and DT in 75.2% and 70.8% of the participants, respectively, and to pertussis toxoid (PT), pertactin (PRN), and filamentous hemagglutinin (FHA) in 94.3%, 92.6%, and 95.0% of the participants, respectively. Anti-PT, anti-PRN, and anti-FHA antibody geometric mean titers in both the groups, were significantly higher post-vaccination compared to pre-vaccination.

CONCLUSIONS

Booster vaccination with SIIPL Tdap was non-inferior to comparator Tdap with respect to immunogenicity against tetanus, diphtheria, and pertussis and was well tolerated.

Silencing PTEN in the fallopian tube promotes enrichment of cancer stem cell-like function through loss of PAX2

High-grade serous ovarian cancer (HGSOC) is the most lethal gynecological malignancy that is primarily detected at the metastatic stage. Most HGSOC originates from the fallopian tube epithelium (FTE) and metastasizes to the ovary before invading the peritoneum; therefore, it is crucial to study disease initiation and progression using FTE-derived models. We previously demonstrated that loss of PTEN from the FTE leads to ovarian cancer. In the present study, loss of PTEN in FTE led to the enrichment of cancer stem cell markers such as LGR5, WNT4, ALDH1, CD44. Interestingly, loss of the transcription factor PAX2, which is a common and early alteration in HGSOC, played a pivotal role in the expression of cancer stem-like cells (CSC) markers and cell function. In addition, loss of PTEN led to the generation of two distinct subpopulations of cells with different CSC marker expression, tumorigenicity, and chemoresistance profiles. Taken together, these data suggest that loss of PTEN induces reprogramming of the FTE cells into a more stem-like phenotype due to loss of PAX2 and provides a model to study early events during the FTE-driven ovarian cancer tumor formation.

Reduced PAX2 expression in murine fallopian tube cells enhances estrogen receptor signaling

High-grade serous ovarian cancer (HGSOC) is thought to progress from a series of precursor lesions in the fallopian tube epithelium (FTE). One of the preneoplastic lesions found in the FTE is called a secretory cell outgrowth (SCOUT), which is partially defined by a loss of paired box 2 (PAX2). In the present study, we developed PAX2-deficient murine cell lines in order to model a SCOUT and to explore the role of PAX2 loss in the etiology of HGSOC. Loss of PAX2 alone in the murine oviductal epithelium (MOE) did not induce changes in proliferation, migration and survival in hypoxia or contribute to resistance to first line therapies, such as cisplatin or paclitaxel. RNA sequencing of MOE PAX2shRNA cells revealed significant alterations in the transcriptome. Silencing of PAX2 in MOE cells produced a messenger RNA expression pattern that recapitulated several aspects of the transcriptome of previously characterized human SCOUTs. RNA-seq analysis and subsequent qPCR validation of this SCOUT model revealed an enrichment of genes involved in estrogen signaling and an increase in expression of estrogen receptor α. MOE PAX2shRNA cells had higher estrogen signaling activity and higher expression of putative estrogen responsive genes both in the presence and absence of exogenous estrogen. In summary, loss of PAX2 in MOE cells is sufficient to transcriptionally recapitulate a human SCOUT, and this model revealed an enrichment of estrogen signaling as a possible route for tumor progression of precursor lesions in the fallopian tube.

Measles in adults in Canada and the United States: implications for measles elimination and eradication

BACKGROUND

Despite the implementation of mass school catch-up campaigns for measles in Canada, an outbreak of measles occurred in early 1997 mostly affecting the adult population. The higher incidence in Canada in adults led us to compare immunization policies and the evolution of measles among adults in Canada and the US.

METHODS

Based on information gathered from both national immunization programmes and surveillance systems.

RESULTS

Although the proportion of cases occurring in adults has increased tremendously in both countries in the past decade, there was no increase in measles incidence in these populations. The most likely factors to explain the higher rate of measles occurring in adults in Canada are the younger age at administration of first dose in Canada, the delay in implementation of a second dose policy in Canada compared with the US combined with the lack of prematriculation immunization requirements in Canadian colleges and universities, and the higher rate of overseas travel to and from Canada. The situation in Canada may also have been exacerbated by incomplete efforts to control measles for many years without attempting to eliminate the disease.

CONCLUSIONS

In order to prevent measles in adults, high-risk groups must be identified and catch-up for selected groups considered. Vaccination of international travellers to endemic areas should be recommended until global elimination has been achieved. Appropriate measles control strategies in younger populations seem to be effective in preventing measles in adults. The experience in Canada and the US suggests that measles transmission in adults is unlikely to be a major impediment to regional elimination or global eradication.

Applications of fluorinated compounds as phases and additives in chromatography and their uses in pharmaceutical analysis

A review is presented of the use of fluorinated phases and fluorine-containing surfactants in chromatography. Additionally, new information is provided on the application of two nonionic perfluorosurfactants as reversed-phase mobile phase additives to enhance chromatographic performance of aromatic amines and some amines of pharmaceutical significance.

Rubella immunization strategies in Canada

Rubella vaccine was introduced in Canada in 1969. Immunization practices and vaccine coverage varied from province to province. In the 1970s the Canadian National Advisory Committee on Immunization endorsed both the policy of mass vaccination--in combination with measles and mumps vaccines--for infants, which seven provinces followed, and that of selective immunization of prepubertal girls, which three provinces followed. In 1982, the Committee advocated a comprehensive policy that incorporated the best features of the two policies and also increased the emphasis on immunization of susceptible adolescent and adult women. As of 1983, in all provinces the vaccine has been routinely administered to infants 12-15 months old; in seven, also to prepubertal girls. After the introduction of rubella vaccine, rubella incidence declined markedly, but the endemic level of rubella incidence remained unchanged. Congenital rubella syndrome (CRS) was added to the federal list of notifiable diseases only in 1979. Sixty-seven CRS cases were reported by five provinces from 1979 to 1983, during which a trend of declining CRS incidence rates (per 100,000 live births) was indicated. However, the numbers of cases are too small to draw definite conclusions regarding the impact of immunization programs.

Mass Phenotyping of Isoniazid Inactivators by Automated Determination of Acetylisoniazid in Urine

An automated procedure is described for phenotyping isoniazid inactivators. The method is based on the color reaction produced by N-acetylisoniazid in aqueous solution, as described by Eidus and Hamilton [Amer. Rev. Resp. Dis. 89, 587 (1964)]. Maximum sampling rate is 60 samples per hour. Results of this procedure correlated well (r = 0.987) with those of a manual phenotyping method.

Comparison of strip and Ziehl-Neelsen methods for staining acid-fast bacteria

The efficiency of the Ziehl-Neelsen method for staining acid-fast bacteria was compared with that of the strip-staining procedure in which one kind of impregnated strip is used to stain the bacteria and another kind for simultaneous decolorization and counter-staining of the smear. The methods were evaluated in 1 136 duplicate smears prepared from digested sputum and 307 pairs of direct smears. The efficiency of the strip method was comparable to that of the Ziehl-Neelsen method with digested sputum; with direct smears, however, it generally depended on the quality of the smear. With thick, uneven smears, lower bacterial counts were obtained by strip staining. On the basis of this trial, the authors suggest improvement of the strip method.

Simplification of isoniazid phenotyping procedure to promote its application in the chemotherapy of tuberculosis

In this investigation a simple urine test for phenotyping isoniazid inactivators is evaluated. In the new method, isoniazid is artificially acetylated in urine and determined by the same colour reaction as that used for acetylisoniazid. Comparative studies showed that the test is reliable and can be performed with accuracy and ease even in poorly equipped laboratories. In contrast to other urine tests, it does not require an expensive spectrophotometer, tedious hydrolysis processing of the samples, or standard curves. The results can be read on a plain colorimeter, or even without any instrument.