Procedure for concentration and conditioning of hybridoma cell culture medium for monoclonal antibody purification

Summary Concentration and conditioning the hybridoma cell culture medium is an important step in the monoclonal antibody purification procedure. This report describes a frequent first-step concentration of the hybridoma cell culture medium and the conditioning of the concentrated medium for the affinity purification of the monoclonal antibodies.     

Allergologic exploration of germins and germin-like proteins,a new class of plant allergens

BACKGROUND: Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used. METHODS: Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT). RESULTS: In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an in vitro assay as well as in SPT. CONCLUSION: Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.     

Cognate CD4(+) T cell licensing of dendritic cells in CD8(+) T cell immunity

Several studies have indicated that CD8(+) T cells require CD4(+) T cell help for memory formation. Evidence suggests that such help can be antigen independent, challenging whether the 'licensing' of dendritic cells (DCs) by CD4(+) T cells is ever required for cytotoxic T lymphocyte (CTL) responses. We show here that help is essential for the generation of CTL immunity to herpes simplex virus 1 and that CD4(+) T cells mediate help in a cognate, antigen-specific way. We provide direct in vivo evidence for DC licensing by helper T cells and show that licensing is rapid and essential for the formation of effector and memory CTLs. In situations in which DCs are poorly licensed by pathogen-derived signals, our findings suggest that CTL immunity may be heavily dependent on cognate DC licensing.     

Diagnostic performance of the Roche AMPLICOR PCR in detecting Neisseria gonorrhoeae in genitourinary specimens from female sex workers in Cotonou, Benin

The objective of this study was to evaluate the diagnostic performance of the Roche multiplex AMPLICOR Chlamydia trachomatis/Neisseria gonorrhoeae PCR test for the detection of Neisseria gonorrhoeae infection in female urine specimens and wet and dry endocervical swabs. Endocervical swabs and urine specimens were collected from 342 female sex workers from Cotonou, Benin, and were tested using the AMPLICOR C. trachomatis/N. gonorrhoeae test (Roche Diagnostic Systems, Inc., Branchburg, N.J.) with internal control detection. Endocervical swabs were also cultured on Thayer-Martin medium. A series of alternate standards that included a combination of all the tests but not the test being evaluated was used to assess the performance of the test with each type of specimen. The sensitivity, specificity, and positive and negative predictive values for the urine were 53.8, 98.9, 93.5, and 87.5%, respectively. Corresponding figures for the wet swab were 91.5, 100, 100, and 97.4%, respectively. Those for the dry swab were 96.3, 96.2, 88.5, and 98.8%, respectively. Based on this study, the AMPLICOR PCR assay showed a low sensitivity for detection of N. gonorrhoeae infection in urine specimens, whereas the test was found to be highly sensitive and specific with endocervical specimens.     

Age-related changes in cardiac autonomic control during sleep

Aging is commonly associated with decreased sleep quality and increased periodic breathing (PB) that can influence heart rate variability (HRV). Cardiac autonomic control, as inferred from HRV analysis, was determined, taking into account the sleep quality and breathing patterns. Two groups of 12 young (21.1 +/- 0.8 years) and 12 older (64.9 +/- 1.9 years) volunteers underwent electroencephalographic, cardiac, and respiratory recordings during one experimental night. Time and frequency domain indices of HRV were calculated in 5-min segments, together with electroencephalographic and respiratory power spectra. In the elderly, large R-R oscillations in the very-low frequency (VLF) range emerged, that reflected the frequency of PB observed in 18% of the sleep time. PB occurred more frequently during rapid eye movement sleep (REM) sleep and caused a significant (P < 0.02) increase in the standard deviation of normal R-R intervals (SDNN) and absolute low-frequency (LF) power. With normal respiratory patterns, SDNN, absolute VLF, LF, and high frequency (HF) power fell during each sleep stage (P < 0.01) compared with young subjects, with no significant sleep-stage dependent variations. An overall decrease (P < 0.01) in normalized HF/(LF + HF) was observed in the elderly, suggesting a predominant loss of parasympathetic activity which may be related to decreased slow-wave sleep duration. These results indicate that two distinct breathing features, implying different levels of autonomic drive to the heart, influence HRV in the elderly during sleep. The breathing pattern must be considered to correctly interpret HRV in the elderly.     

Comparison of contact and spatial repellency of catnip oil and N,N-diethyl-3-methylbenzamide (deet) against mosquitoes

Nepetalactone, the primary component of catnip oil, was compared with the repellent N,N-diethyl-3-methylbenzamide (deet) for its ability to affect the host-seeking ability of Aedes aegypti (L.). A triple cage olfactometer was used to bioassay each substance and to assess its attraction inhibition (spatial repellent) attributes when combined with the following attractants: carbon dioxide, acetone, a blend of L-lactic acid and acetone, and human odors. Repellent tests were conducted with each substance against female Ae. aegypti, Anopheles albimanus Weidemann, and Anopheles quadrimaculatus Say. Catnip oil and deet were both weakly attractive to Ae. aegypti, catnip oil was the better spatial repellent, whereas deet was a more effective contact repellent in tests with all three species of mosquitoes.     

Transcription Factor PU.1 Promotes Conventional Dendritic Cell Identity and Function via Induction of Transcriptional Regulator DC-SCRIPT

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BEAUTY and the breast: is adjuvant chemotherapy the right time for a beauty boost? Lessons learned from a large randomized controlled trial

Quality of Life Research - Beauty care (BTC) is offered at many cancer hospitals having a great uptake among patients. Nevertheless, its benefits in the Quality of life (QoL) of cancer survivors...