First-Line Chemoimmunotherapy versus Sequential Platinum-Based Chemotherapy Followed by Immunotherapy in Patients with Non-Small Cell Lung Cancer with ≤49% Programmed Death-Ligand 1 Expression: A Real-World Multicenter Retrospective Study

BACKGROUND

The long overall survival (OS) observed among patients with non-small cell lung cancer (NSCLC) with high programmed death-ligand 1 (PD-L1) expression in chemoimmunotherapy (CIT) groups in previous phase III trials suggests the limited efficacy of CIT among the subgroup with ≤49% PD-L1 expression on tumor cells. Hence, sequential treatment with first-line platinum-based chemotherapy followed by second-line immune checkpoint inhibitor treatment (SEQ) is an option. This study examined whether first-line CIT would provide better outcomes than SEQ in patients with advanced NSCLC with ≤49% PD-L1 expression.

METHODS

This retrospective study evaluated patients with untreated NSCLC who received first-line CIT or SEQ at nine hospitals in Japan. OS, progression-free survival (PFS), PFS-2 (the time from first-line treatment to progression to second-line treatment or death), and other related outcomes were evaluated between the CIT and SEQ groups.

RESULTS

Among the 305 enrolled patients, 234 eligible patients were analyzed: 165 in the CIT group and 69 in the SEQ group. The COX proportional hazards model suggested a significant interaction between PD-L1 expression and OS (p = 0.006). OS in the CIT group was significantly longer than that in the SEQ group in the 1-49% PD-L1 expression subgroup but not in the <1% PD-L1 expression subgroup. Among the subgroup with 1-49% PD-L1 expression, the CIT group exhibited longer median PFS than the SEQ group (CIT: 9.3 months (95% CI: 6.7-14.8) vs. SEQ:5.5 months (95% CI: 4.5-6.1); p < 0.001), while the median PFS in the CIT group was not statistically longer than the median PFS-2 in the SEQ group (p = 0.586). There was no significant difference between the median PFS in the CIT and SEQ groups among the <1% PD-L1 expression subgroup (p = 0.883); the median PFS-2 in the SEQ group was significantly longer than the median PFS in the CIT group (10.5 months (95% CI: 5.9-15.3) vs. 6.4 months (95% CI: 4.9-7.5); p = 0.024).

CONCLUSIONS

CIT is recommended for patients with NSCLC with 1-49% PD-L1 expression because it significantly improved OS and PFS compared to SEQ. CIT had limited benefits in patients with <1% PD-L1 expression, and the median PFS-2 in the SEQ group was significantly longer than the median PFS in the CIT group. These findings will help physicians select the most suitable treatment option for patients with NSCLC, considering PD-L1 expressions.

A Case of Takotsubo Cardiomyopathy Triggered by Asthma Exacerbation After mRNA-based Vaccination for COVID-19

It is recommended to get the multiple coronavirus disease 2019 (COVID-19) vaccinations for almost all people including asthma patients. A 70-year-old Japanese woman with asthma experienced worsening of respiratory symptoms after the second dose of the mRNA-based COVID-19 vaccine BNT162b2. The patient had hypercapnic respiratory failure and cardiac-apex ballooning and was diagnosed with takotsubo cardiomyopathy induced by asthma exacerbation. Therapies for asthma exacerbation resulted in prompt improvement of respiratory failure and cardiac-apex ballooning. Our findings suggest that asthma patients are prone to exacerbations after receiving the COVID-19 vaccination; therefore, stratification of the patients at risk is required.

Measurement of glycated hemoglobin and glycated albumin in umbilical cord: evaluation of the glycemic control indicators in neonates

OBJECTIVE

As neonatal blood contains a high proportion of fetal hemoglobin (HbF), it is difficult to use high-performance liquid chromatography (HPLC) method, latex-immunoturbidimetry (LA) method and enzymatic methods, which determine hemoglobin A(1C) (HbA(1C)) in order to provide the glycemic control indicators of neonates. In this study, we evaluated glycated hemoglobin (GHb) and glycated albumin (GA) as appropriate indicators of the glycemic control in the neonatal period.

STUDY DESIGN

Umbilical cord blood samples collected during delivery were subjected to measurements of GHb (HPLC methods using two different instruments, LA method, enzymatic method and affinity method) and serum GA.

RESULT

HbA(1C) levels determined by the HPLC method, the LA method and the enzymatic method were as low as <3.0% in all the cases. Although GHb determined by the affinity method was 3.6 ± 0.2%, this method may not measure accurately the values of glycated HbF plus glycated HbA. Serum GA was 9.4 ± 1.1%.

CONCLUSION

We speculate that serum GA, but not GHb, could be used as glycemic control indicators in neonates.

Spontaneous reversal of the developmental aging of normal human cells following transcriptional reprogramming

AIM

To determine whether transcriptional reprogramming is capable of reversing the developmental aging of normal human somatic cells to an embryonic state.

MATERIALS & METHODS

An isogenic system was utilized to facilitate an accurate assessment of the reprogramming of telomere restriction fragment (TRF) length of aged differentiated cells to that of the human embryonic stem (hES) cell line from which they were originally derived. An hES-derived mortal clonal cell strain EN13 was reprogrammed by SOX2, OCT4 and KLF4. The six resulting induced pluripotent stem (iPS) cell lines were surveyed for telomere length, telomerase activity and telomere-related gene expression. In addition, we measured all these parameters in widely-used hES and iPS cell lines and compared the results to those obtained in the six new isogenic iPS cell lines.

RESULTS

We observed variable but relatively long TRF lengths in three widely studied hES cell lines (16.09-21.1 kb) but markedly shorter TRF lengths (6.4-12.6 kb) in five similarly widely studied iPS cell lines. Transcriptome analysis comparing these hES and iPS cell lines showed modest variation in a small subset of genes implicated in telomere length regulation. However, iPS cell lines consistently showed reduced levels of telomerase activity compared with hES cell lines. In order to verify these results in an isogenic background, we generated six iPS cell clones from the hES-derived cell line EN13. These iPS cell clones showed initial telomere lengths comparable to the parental EN13 cells, had telomerase activity, expressed embryonic stem cell markers and had a telomere-related transcriptome similar to hES cells. Subsequent culture of five out of six lines generally showed telomere shortening to lengths similar to that observed in the widely distributed iPS lines. However, the clone EH3, with relatively high levels of telomerase activity, progressively increased TRF length over 60 days of serial culture back to that of the parental hES cell line.

CONCLUSION

Prematurely aged (shortened) telomeres appears to be a common feature of iPS cells created by current pluripotency protocols. However, the spontaneous appearance of lines that express sufficient telomerase activity to extend telomere length may allow the reversal of developmental aging in human cells for use in regenerative medicine.

Effects of thyroid hormone on serum glycated albumin levels: study on non-diabetic subjects

Glycated albumin (GA) is used alongside glycated hemoglobin (HbA(1C)) as an indicator of glycemic control. Although serum GA levels are affected mainly by plasma glucose, they are also influenced by serum albumin metabolism. Thyroid hormone is known to promote albumin catabolism, and it is thus thought to affect serum GA levels. In the present study, the effects of thyroid hormone on serum GA measurements were investigated in patients with thyroid dysfunction. Six patients with untreated hypothyroidism and 17 patients with untreated thyrotoxicosis were investigated. Patients who had anemia or diabetes were excluded. A total of 25 non-diabetic, euthyroid individuals were enrolled as controls. HbA(1C), serum GA, thyroid-stimulating hormone (TSH), free triiodothyronine (T(3)), and free thyroxine (T(4)) levels were measured in all these subjects, and their relationships were examined. Although no intergroup differences were observed for HbA(1C), serum GA was significantly higher among patients with hypothyroidism than controls, and significantly lower among patients with thyrotoxicosis. Serum GA had a significant positive correlation with serum TSH and significant inverse correlations with free T(3) and free T(4). Thyroid hormone levels are inversely associated with serum GA levels. Cautions are necessary when evaluating serum GA levels in patients with thyroid dysfunction.

Fine mapping and DNA fiber FISH analysis locates the tobamovirus resistance gene L3 of Capsicum chinense in a 400-kb region of R-like genes cluster embedded in highly repetitive sequences

The tobamovirus resistance gene L(3) of Capsicum chinense was mapped using an intra-specific F2 population (2,016 individuals) of Capsicum annuum cultivars, into one of which had been introduced the C. chinense L(3) gene, and an inter-specific F2 population (3,391 individuals) between C. chinense and Capsicum frutescence. Analysis of a BAC library with an AFLP marker closely linked to L(3)-resistance revealed the presence of homologs of the tomato disease resistance gene I2. Partial or full-length coding sequences were cloned by degenerate PCR from 35 different pepper I2 homologs and 17 genetic markers were generated in the inter-specific combination. The L(3) gene was mapped between I2 homolog marker IH1-04 and BAC-end marker 189D23M, and located within a region encompassing two different BAC contigs consisting of four and one clones, respectively. DNA fiber FISH analysis revealed that these two contigs are separated from each other by about 30 kb. DNA fiber FISH results and Southern blotting of the BAC clones suggested that the L(3) locus-containing region is rich in highly repetitive sequences. Southern blot analysis indicated that the two BAC contigs contain more than ten copies of the I2 homologs. In contrast to the inter-specific F2 population, no recombinant progeny were identified to have a crossover point within two BAC contigs consisting of seven and two clones in the intra-specific F2 population. Moreover, distribution of the crossover points differed between the two populations, suggesting linkage disequilibrium in the region containing the L locus.

[The effects of pleasantness of verbal messages on perceived deceptiveness in romantic relationships]

The present study examined the effects of pleasantness expressed in verbal messages on their perceived deceptiveness. The hypothesis was that pleasant messages are perceived as less deceptive than neutral or unpleasant ones. To test the hypothesis, three types of messages were constructed: pleasant, neutral, and unpleasant. Sixty-seven university students answered the questionnaire in which they rated, on seven-point semantic differential scales, perceived deceptiveness in one of the three types of messages. The result indicated that the unpleasant messages were perceived as the most deceptive, while the pleasant ones the least deceptive. The computer program "GPOWER" was used in order to obtain appropriate sample size.

Isolation and characterization of the three Waxy genes encoding the granule-bound starch synthase in hexaploid wheat

Complete genomic DNA sequences of three homoeologous Waxy structural genes, located on the chromosomes 7A, 4A, and 7D in hexaploid wheat (Triticum aestivum L. cv. Chinese Spring), were separately determined and analyzed. Those structural genes in lengths from start to stop codon were 2781bp in Wx-7A, 2794bp in Wx-4A, and 2862bp in Wx-7D, each of which consisted of 11 exons and ten introns. They were closely similar to one another in the nucleotide sequences, with 95.6-96.3% homology in mature protein regions, 88. 7-93.0% in transit-peptide regions, and 70.5-75.2% in the introns. These wheat Waxy genes were GC-rich when compared with standard values for plant genomes reported so far. This was reflected in the extremely high G/C occupation frequency at the third position of the codons in the coding regions. The sequence divergence in the exon regions was mostly due to the substitution of nucleotides, whereas that found in the introns was attributed to substitution, insertion and/or deletion of nucleotides. Only the Wx-4A gene contained a trinucleotide insertion (CAA) in the region encoding the transit peptide. Most of the substitutions observed in the exon regions were categorized as synonymous, and higher sequence similarities (96.5-97. 4%) were conserved at the protein level. The phylogenetic tree obtained in terms of the amino acid sequence variations showed a well-resolved phylogenetic relationship among wheat Waxy genes and those from other plants.

[Color Doppler signal enhancement with SH/TH-508 in pancreatic tumors]

In this report, we showed the efficacy of a new contrast agent (SH/TA-508, Schering AG, Germany) for color Doppler imaging of the pancreatic tumors. In pancreatic ductal cancer, no enhancement of the lesion was observed, but vascular invasion by cancer became to be easily evaluated. On the other hand, hypervascular tumors such as islet cell tumor and cystadenocarcinoma, were increased in color Doppler signals of vessels by SH/TA-508. We concluded that SH/TA-508 was useful for evaluating the vascular invasion by pancreatic cancer as well as vascularity of hypervascular mass and solid component of cystic neoplasma.

Aromatase gene expression and its exon I usage in human breast tumors. Detection of aromatase messenger RNA by reverse transcription-polymerase chain reaction

The expression of aromatase in human breast tumors has been studied by the reverse-transcription polymerase chain reaction (RT-PCR) method on 70 breast tissue specimens. An RT-PCR analysis using two oligonucleotide primers derived from the exon II of the human aromatase gene revealed that aromatase mRNA was detected in all but three tissue specimens. Furthermore, primer-directed RT-PCR was performed to determine the exon I usage in aromatase mRNA in these breast tumor specimens. The analysis has revealed that exons I.3 and PII are the two major exon Is present in aromatase mRNA isolated from breast tumors, suggesting that promoters I.3 and II are the major promoters driving aromatase expression in breast cancer and surrounding adipose stromal cells. The RT-PCR analysis also detected two products, I.3A (334 bp in length) and I.3B (222 bp in length), when it was carried out using a primer derived from exon I.3 and a reverse primer derived from exon II. The nucleotide sequences of these products have been determined and indicate that I.3A contains a region which was previously thought to be an intron. In addition, RT-PCR analyses of RNA isolated from eight pairs of breast tumor and neighboring normal tissue specimens were performed to evaluate the exon I usage and the distribution of I.3A- and I.3B-containing aromatase RNA messages in breast tumor and neighboring normal tissues. The results suggest that I.3B- and I.3A-containing messages are mainly present in breast tumor and neighboring normal tissues, respectively. Finally, the exon I/promoter usage for aromatase expression in eight cell lines (skin fibroblast, MCF-7, MDA-MB-231, T-47D, SK-BR-3, JAR, OVCAR-3, and human adipose stromal cells) was examined by primer-directed RT-PCR analyses. These studies provide a basis for further evaluation of the control mechanism of aromatase expression and estrogen biosynthesis in breast tumors.

[The screening of hepatitis virus and its efficacy]

1. Infection of hepatitis A virus (HAV) was prevented with hepatitis A vaccine. High risk groups of HAV infection should be inoculated this vaccine because Japanese peoples less than 40 years old didn't have immunity for HAV. 2. Infection of hepatitis E virus (HEV) was scarcely observed in Japan. 3. Infection of hepatitis B virus (HBV) by blood transfusion was eradicated after the screening with anti-HBc antibody for blood donors. And maternal transmissions of HBV and infections of HBV in hospital were protected by HB-globulin and hepatitis B vaccine. 4. Infection of hepatitis D virus (HDV) was protected by HB-globulin and hepatitis B vaccine. 5. Infection of hepatitis C virus (HCV) by blood transfusion markedly decreased after the screening with anti-HCV for blood donors. We can't prevent a maternal transmission of HCV but its frequency is low (about 10%). And acute hepatitis C due to an infection of HCV in hospital can be prevented by the treatment with interferon in the Workmen's Accident Compensation Insurance.

Quantitative analysis of Lewis antigens on erythrocytes by flow cytometry

We have developed a method for the quantitative analysis of Lewis antigens on human red blood cells (RBC) using immunofluorescence labeling and flow cytometry. Initially, Lewis a and Lewis b (Le(a) and Le(b)) antigens were labeled with monoclonal anti-Le(a) or anti-Le(b) antibodies followed by labeling with the fluorescein isothiocyanate (FITC)-conjugated second antibody. This method was not sensitive enough to identify the Lewis antigens on RBC, although the FITC method is very commonly used for antigens on white blood cells. Next, we selected the enhanced labeling technique using the avidin-biotin procedure. Biotinylated anti-mouse IgM was used for the second label and the reaction with R-phycoerythrin (RPE)-conjugated streptavidin followed to produce the fluorescence. The method was found to be effective for our objectives. From the results analyzed by the enhanced labeling technique, differences were not found in either the levels of the antigen-positive percentage and the peak mean channel of Le(a) antigens on RBC in the groups of blood type O and A (in ABO system). On the other hand, both the levels of Le(b) antigens on RBC were higher in the groups of blood type O than in those of blood type A. We found both Le(a) and Le(b) antigens on RBC from a few blood type O subjects. We conclude that enhanced labeling and flow cytometry constitute a useful technique for the determination of Lewis antigens on RBC and that this method enables the precise quantification of such antigens.

Aromatase gene is amplified in MCF-7 human breast cancer cells

The levels of the aromatase gene and its expression in MCF-7 human breast cancer cells and seven additional cultured cells were investigated. Using normal human foreskin fibroblasts as the control, the aromatase gene appeared to be amplified in MCF-7 cells as shown by Southern and DNA slot blot analyses utilizing human placental aromatase cDNA as the probe. However, the promoter I.1 and the first exon of the aromatase gene were not amplified in MCF-7 cells based on results obtained from DNA slot blot analysis using oligonucleotide probes having sequences derived from those regions of human aromatase gene. Aromatase was expressed at a very low level in this cell line as indicated by Northern blot analysis to measure the level of aromatase mRNA, immunoprecipitation analysis to measure the level of aromatase protein, and aromatase activity measurement. Furthermore, nucleotide sequence analysis of the aromatase cDNA obtained from MCF-7 cells by PCR techniques, revealed no sequence difference from that of the enzyme expressed in placenta. These results lead us to conclude that the expression of aromatase in MCF-7 cells is under the control of an unusual promoter and aromatase gene expression is repressed at the transcriptional level in these cells.

Structure and function of the hepatic form of 11 beta-hydroxysteroid dehydrogenase in the squirrel monkey, an animal model of glucocorticoid resistance

Both cortisol and aldosterone bind to and activate the mineralocorticoid receptor. Cortisol concentrations are generally 100- to 200-fold higher than aldosterone concentrations, yet mineralocorticoids clearly exert effects different from glucocorticoids. One hypothesis is that 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD), which converts cortisol to biologically inactive cortisone, protects the mineralocorticoid receptor from cortisol. The circulating concentrations of cortisol in the squirrel monkey are 20- to 50-fold higher than human cortisol concentrations, yet this animal has no evidence of glucocorticoid or mineralocorticoid excess. We used this experiment of nature to test the hypotheses that the known (hepatic) form of 11 beta-HSD protects renal mineralocorticoid receptors from the action of cortisol and that it modulates glucocorticoid concentrations in target tissues. Using a long oligonucleotide based on the rat sequence, we cloned the squirrel monkey 11 beta-HSD complementary DNA and gene. The encoded monkey amino acid sequence is 75% and 91% identical to the corresponding rat and human sequences, respectively. The tissue abundance of the messenger RNA for the monkey enzyme was similar to or less than that seen for the rat and human enzymes. Both the monkey and human 11 beta-HSD complementary DNAs were cloned into an expression vector and used to transfect cultures of Chinese hamster ovary cells. Both vectors were transcribed and translated into equivalent amounts of 11 beta-HSD enzyme. The monkey enzyme was slightly more efficient than the human enzyme in converting [3H]cortisol to cortisone, and estimates of the Michaelis-Menten constant and maximum velocity of both enzymes are similar. These data indicate that the abundance and activity of the hepatic form of 11 beta-HSD are insufficient to inactivate the very high concentrations of cortisol in the squirrel monkey, suggesting that this form of 11 beta-HSD does not defend the mineralocorticoid receptor or protect tissues from high cortisol concentrations. Rather, this enzyme appears to favor conversion of cortisone to cortisol, thus maximizing tissue concentrations of cortisol to overcome glucocorticoid resistance associated with a 50% reduction in glucococorticoid receptors.

The effect of non-insulin-dependent diabetes on serum concentrations of tumor-associated carbohydrate antigens of CA19-9, CA-50, and sialyl SSEA-1 in association with the Lewis blood phenotype

Serum concentrations of the tumor-associated carbohydrate antigens CA19-9, CA-50, and sialyl SSEA-1 were measured in non-insulin-dependent diabetic patients without diseases causing the elevation of those antigens, and the relationship to diabetic conditions was studied. The patients of the Lewis blood group phenotype of Lea (23%) had higher serum CA19-9, CA-50, and sialyl SSEA-1 than those of Leb (67%) and Le(-) (10%). Lea patients with high HbA1c (greater than 10%) had significantly higher serum CA19-9 and CA-50 than those with low HbA1c (less than or equal to 7%). Leb patients with high HbA1c also had elevated CA19-9 and sialyl SSEA-1. In Leb patients, diabetic nephropathy was associated with increased CA19-9 levels. Diabetic retinopathy was also accompanied by high carbohydrate antigens in Leb patients, but the difference was not significant. Leb patients treated with sulfonylurea or insulin had increased CA19-9 and CA-50. The changes in serum concentrations of these carbohydrate antigens might have some relationship not only to the Lewis blood phenotype, but also to diabetes.

Influence of pregnancy and lactation on serum and breast fluid estrogen levels: implications for breast cancer risk

We investigated estrogen (estrone and estradiol) levels in serum and in nipple aspirates of breast fluid in relation to reproductive and menopausal characteristics in 104 normal women. In general, breast fluid and serum estrogen levels were not correlated and breast fluid estrogen levels were approximately 5 to 45 times higher than serum levels. Serum estrogen levels were lower in post-menopausal than in pre-menopausal women. In contrast, breast fluid estrogen levels were approximately the same in pre- and post-menopausal women. Breast fluid estrogen mean levels were lower in pre-menopausal parous women than in nulligravidous or nulliparous women whereas serum estrogen levels did not differ in these 3 groups. Breast fluid estrogen levels were positively correlated with months since last birth or since last breast-feeding. Estrogen levels were low in nipple aspirates of breast milk but gradually increased in breast fluid of non-lactating women over a period of several years after cessation of lactation. Serum estrogen levels did not increase with months since last breast-feeding. We were unable to evaluate the post-partum effect of pregnancy without lactation due to the small numbers of these subjects. The high concentrations of estrogen in breast fluid and the absence of a relationship to serum estrogen levels may explain why prior serum studies have failed to link variations in serum estrogens with breast cancer risk. The prolonged low levels of breast fluid estrogens following full-term birth and lactation may, in part, provide a mechanism by which parity reduces breast cancer risk.

Benign and malignant breast disease: initial study results of serum and breast fluid analyses of endogenous estrogens

Design, methods, and study population of a long-term multidisciplinary investigation of benign and malignant breast disease were reported. This initial report focused on the relation of menstrual, reproductive, and other factors to serum and breast fluid estrogen measures [estradiol (E2), estrone (E1), percent free estrogen, and sex hormone binding globulin] among control women. After adjustment for the factors found to be related to the various estrogen measures, estrogen levels in women with benign and malignant disease were compared to those of controls. Findings were as follows: a) little evidence of any relation of most breast cancer risk factors with the various serum estrogen parameters studied; b) differences in breast fluid estrogen levels that may be relevant to the protective effect of parity on breast cancer risk; c) markedly higher levels of E2 and E1 in breast fluid than in serum and no evidence of a correlation of serum with breast fluid measures; d) no support for the hypothesis that breast cancer patients have higher serum percent free E2 than controls or women with benign breast disease; and e) higher breast fluid E2 and E1 levels in women with biopsied benign breast disease than in controls.

Researches in network development of JUNET

JUNET was developed in order to provide a testing environment for studies of computer networking and distributed processing by connecting a large number of computers and by providing actual services for the users. Research interests in development of the network have been focused on resource name managing, Japanese character handling and communication technologies.

For the name managements, the hierarchical domain concept is employed to construct a name space for the network, and a mechanism for text message exchange is implemented using the concept. An environment for text message exchange using Japanese characters is achieved as results of general discussions to handle 16-bit Kanji codes in computers. Efficient data transmissions with the high speed modems are achieved by a new UUCP protocol and the dial-up IP link mechanism developed with a tty driver which provides host-to-modem flow control mechanism.

As the result of researches described above, JUNET currently connects various types of organizations relating computer science which are 87 organizations with more than 250 computers in number. It connects universities and major research laboratories in Japan, and the protocols currently used are TCP/IP over leased lines as well as dial-up lines, and UUCP over dial-up lines. The services such as electronic mail and network news have been provided since the network was started, and special technologies for Japanese character handling, name servers, and multimedia mail supports have been developed.

In this paper, the current status of JUNET and its research results in development of the network are described.

The physiochemical and immunological characteristics of rat lymph binding protein for 25-hydroxyvitamin D3

The binding proteins for 25-hydroxyvitamin D3(25-OH-D3) in rat lymph and plasma were purified to apparent homogeneity as determined by sodium dodecyl sulfate disc gel electrophoresis. The purification procedures included the following techniques: gel filtration on Sephadex G-100 and G-200; affinity chromatography on Blue Sepharose CL-6B; ion-exchange chromatography on DEAE-Sepharose CL-6B; chromatofocussing on a Mono P column. Both proteins from lymph and plasma were eluted with the same retention time from an isoelectric column at a pH of approximately 4.53 and showed nearly identical data on the analysis of amino acid composition. When specific anti-lymph 25-OH-D3-binding protein antiserum was prepared in a rabbit, and Ouchterlony immunodiffusion was performed, the same precipitate line was observed on both lymph and plasma binding proteins. These results strongly suggest that a common transport protein exists in both rat lymph and plasma and circulates in the blood-lymph system.