Characterization of mouse switch variant antibodies by matrix-assisted laser desorption ionization mass spectrometry and electrospray ionization mass spectrometry

The amino acid sequences of mouse monoclonal antibodies have been characterized completely by mass spectrometry. Antibodies used in the present study were derived from mouse switch variant cell lines that produce four kinds of immunoglobulin Gs (IgGs). The amino acid sequences of these antibodies had not been estimated from the corresponding DNA sequence, so the sequences of IgGs derived from other strains were used as references in this study. Intra- and interchain disulfide bonds of the IgGs were reduced and carboxymethylated and the products were subjected to proteolytic digestion. The existence of N-linked oligosaccharides also was taken into account. The capabilities and limitations of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry and capillary liquid chromatography-electrospray ionization mass spectrometry are discussed in the structural characterization of the antibodies. Based on our results, allotypes of the antibodies examined are discussed. This study shows that amino acid sequences of proteins, such as IgG, can be investigated without information about the corresponding DNA sequence if appropriate reference sequences derived from other strains can be used

Rapid diagnosis of drug intoxication using novel NAGINATA TM gas chromatography/mass spectrometry software

In Japan, not only the classical stimulant, methamphetamine, but also a wide variety of illicit drugs and designer drugs are abused by juveniles. It is, however, difficult to screen these drugs in human urine due to the poor availability of high-quality standards. Therefore, it is important to develop a screening method that does not require the use of standard compounds. Furthermore, if we can obtain approximate drug concentrations in biological fluids by the first screening procedure, the subsequent treatment of the patient and forensic diagnosis can be carried out more rapidly and exact quantitative analysis performed more efficiently. We have devised a rapid screening method for the simultaneous semi-quantitative analysis of 30 abused drugs using gas chromatography/mass spectrometry (GC/MS) with a retention time locking technique. Based on this method, an 'abused drugs database' was constructed including retention time (RT), qualifier ion/target ion (QT) percentage and calibration curve (values of slope and intercept) using the novel GC/MS software, NAGINATA TM . We compared the analytical results obtained by this method using the constructed database with those from conventional methods in six forensic cases. The number of confirmed drugs and concentrations obtained by the established method was comparable with that obtained by conventional methods. We found a significant improvement in the time for data analysis, and qualitative and quantitative information about each drug was obtained without using standards. Therefore, this new screening procedure using NAGINATA TM has potential for the rapid identification of poisoning and should be useful in clinical and forensic toxicological analyses

Preparation of sponge cakes without eggs : substitution of Tukuneimo (Dioscrea Batatas Decne)

We prepared sponge cakes without eggs for egg-allergic patients. We prepared sponge cakes as authentically as possible by substituting Tukuneimo (Dioscrea Batatas Decne) for eggs. Baking powder (BP) was suitable as a leavening agent. The use of foam stabilizers (Taiyo Chemistry Co. : SP) resulted in a 50% reduction in the amount of Tukuneimo needed. The coloring of sponge cakes looked more authentic by adding vitamin B2. Adding cocoa or green tea powder masked the smell peculiar to Tukuneimo

Myeloma-Associated Fanconi Syndrome Due to λ-Light Chain Crystal Deposition

Multiple myeloma is uncommonly complicated with Fanconi syndrome, due to the deposition of light chains in renal tubular epithelial cells. A 76-year-old man with λ-Bence Jones type multiple myeloma had adult Fanconi syndrome. Electron microscopy showed that rhomboid, high-density substances of various sizes, were accumulated in the proximal tubular epithelial cells on renal biopsy. Immunoelectron microscopy demon-strated that these crystals were λ-light chains. The deposition of κ-light chain in patients with myeloma-associated Fanconi syndrome has been known. This is the 1st report showing the deposition of λ-light chain in renal proximal tubular epithelial cells

Immunological evaluation of peptide vaccination for cancer patients with the HLA-A26 allele

To develop a peptide vaccine for cancer patients with the HLA-A26 allele, which is a minor population worldwide, we investigated the immunological responses of HLA-A26+ ⁄ A26+ cancer patients to four different CTL epitope peptides under personalized peptide vaccine regimens. In personalized peptide vaccine regimens, two to four peptides showing positive peptide-specific IgG responses in pre-vaccination plasma were selected from the four peptide candidates applicable for HLA-A26+ ⁄ A26+ cancer patients and administered s.c. Peptide-specific CTL and IgG responses along with cytokine levels were measured before and after vaccination. Cell surface markers in PBMCs and plasma cytokine levels were also measured. In this study, 21 advanced cancer patients, including seven lung, three breast, two pancreas, and two colon cancer patients, were enrolled. Their HLAA26 genotypes were HLA-A26:01 (n = 24), HLA-A26:03 (n = 10), and HLA-A26:02 (n = 8). One, 14, and 6 patients received two, three, and four peptides, respectively. Grade 1 or 2 skin reactions at the injection sites were observed in the majority of patients, but no severe adverse events related to the vaccination were observed. Peptide-specific CTL responses were augmented in 39% or 22% of patients after one or two cycles of vaccination, respectively. Notably, peptide-specific IgG were augmented in 63% or 100% of patients after one or two cycles of vaccination, respectively. Personalized peptide vaccines with these four CTL epitope peptides could be feasible for HLA-A26+ advanced cancer patients because of their safety and higher rates of immunological responses.This study was supported in part by the Japan Agency for Medical Research and development, AMED, a research program of the Regional Innovation Cluster Program of the Ministry of Education, Culture, Sports, Science and Technology of Japan, and a grant from the Sendai Kousei Hospital