Precise immunological evaluation rationalizes the design of a self-adjuvanting vaccine composed of glycan antigen,TLR1/2 ligand,and T-helper cell epitope

Sialyl-Tn (STn), overexpressed on various tumors, has been investigated for its application in anti-cancer vaccine therapy. However, Theratope, an STn-based vaccine, failed in the phase III clinical trial due to poor immunogenicity and epitope suppression by the foreign carrier protein. We therefore developed a self-adjuvanting STn based-vaccine, a conjugate of clustered STn (triSTn) antigen, TLR1/2 ligand (Pam₃CSK₄), and T-helper (Th) cell epitope, and found that this three-component self-adjuvanting vaccine effectively resulted in the production of anti-triSTn IgG antibodies. We herein analyzed immune responses induced by this self-adjuvanting vaccine in detail. We newly synthesized two-component vaccines, i.e., Pam₃CSK₄- or Th epitope-conjugated triSTn, as references to evaluate the immune-stimulating functions of Pam₃CSK₄ and Th epitope. Immunological evaluation of the synthesized vaccine candidates revealed that Pam₃CSK₄ was essential for antibody production, indicating that the uptake of triSTn antigen by antigen-presenting cells (APCs) was promoted by the recognition of Pam₃CSK₄ by TLR1/2. The function of the Th epitope was also confirmed. Th cell activation was important for boosting antibody production and IgG subclass switching. Furthermore, flow cytometric analyses of immune cells, including T cells, B cells, dendritic cells, and other monocytes, were first employed in the evaluation of self-adjuvanting vaccines and revealed that the three-component vaccine was able to induce antigen-specific immune responses for efficient antibody production without excessive inflammatory responses. Importantly, the co-administration of Freund''s adjuvants was suggested to cause excessive myeloid cell accumulation and decreased plasma cell differentiation. These results demonstrate that vaccines can be designed to achieve the desired immune responses via the bottom-up construction of each immune element.

Detailed analysis of a three-component self-adjuvanting vaccine revealed that conjugate vaccines can be designed to achieve the desired immune responses via bottom-up construction of the necessary immune elements.     

Repeated Necrotizing Lymphadenitis with MEFV Gene Mutations

We herein report a 36-year-old man with repeated necrotizing lymphadenitis due to MEFV gene mutations. The patient''s chief complaints were a fever and painful cervical lymphadenopathy. We diagnosed him with necrotizing lymphadenitis based on the pathological findings of the lymph nodes and the exclusion of other differential diseases. The same episode recurred four times. We speculated the involvement of autoinflammatory backgrounds and detected MEFV gene mutations of E148Q (homo), P369S, and R408Q. Considering the elevation of interleukin-18, these mutations probably played roles in the repeated necrotizing lymphadenitis.     

Risk Factors for Complications Associated with Peripherally Inserted Central Catheters During Induction Chemotherapy for Acute Myeloid Leukemia

Objective Peripherally inserted central catheters (PICCs) are widely used in patients with hematologic malignancies. However, the risks of PICC-related complications during chemotherapy for acute myeloid leukemia (AML) are not fully understood. Methods We conducted a retrospective review of 128 adult patients with AML who received induction therapy by way of PICC insertion between 2012 and 2019. Results The median duration of PICC insertion was 30 days. The incidence rate of catheter-related bloodstream infection (CRBSI) was 2.4% at 30 days, and women were more likely to suffer from CRBSI than men. Local reactions at the insertion site were observed in 56 patients; however, these events did not predict CRBSI. The incidence rates of catheter-related thrombosis (CRT) were 1.6% at 30 days. Obesity put patients at an increased risk for CRT. Unexpected PICC removal occurred in 59 patients, and women were at a higher risk of catheter removal than men. Conclusion Low PICC-related complication rates, possibly associated with high rates of catheter removal, were observed during intensive chemotherapy for AML. Women and obese patients require careful monitoring of their PICC. Procedures to achieve appropriate PICC removal without increasing the complication rate need to be considered.     

A questionnaire about radiation safety management of the draining-water system at nuclear medicine facilities

We conducted a questionnaire survey about radiation-safety management condition in Japanese nuclear medicine facilities to make materials of proposition for more reasonable management of medical radioactive waste. We distributed a questionnaire to institutions equipped with Nuclear Medicine facilities. Of 1,125 institutions, 642 institutes (52.8%) returned effective answers. The questionnaire covered the following areas: 1) scale of an institution, 2) presence of enforcement of radiotherapy, 3) system of a tank, 4) size and number of each tank, 5) a form of draining-water system, 6) a displacement in a radioactive rays management area, 7) a measurement method of the concentration of medical radioactive waste in draining water system, 8) planned and used quantity of radioisotopes for medical examination and treatment, 9) an average displacement of hospital for one month. In most institutions, a ratio of dose limitation of radioisotope in draining-water system was less than 1.0, defined as an upper limitation in ordinance. In 499 hospitals without facilities of hospitalization for unsealed radioisotope therapy, 473 hospitals reported that sum of ratios of dose limits in a draining-water system was less than 1.0. It was calculated by used dose of radioisotope and monthly displacement from hospital, on the premise that all used radioisotope entered in the general draining-water system. When a drainage including radioactivity from a controlled area join with that from other area before it flows out of a institution, it may be diluted and its radioactive concentration should be less than its upper limitation defined in the rule. Especially, in all institutions with a monthly displacement of more than 25,000 m3, the sum of ratio of the concentration of each radionuclide to the concentration limit dose calculated by used dose of radioisotope, indicated less than 1.0.     

Effect of Ventilatory Settings on Accuracy of Cardiac Output Measurement Using Partial CO2 Rebreathing

Background: Recently, a new device has been developed to measure cardiac output noninvasively using partial carbon dioxide (CO2) rebreathing. Because this technique uses CO2 rebreathing, the authors suspected that ventilatory settings, such as tidal volume and ventilatory mode, would affect its accuracy: they conducted this study to investigate which parameters affect the accuracy of the measurement.

Methods: The authors enrolled 25 pharmacologically paralyzed adult post-cardiac surgery patients. They applied six ventilatory settings in random order: (1) volume-controlled ventilation with inspired tidal volume (VT) of 12 ml/kg; (2) volume-controlled ventilation with VT of 6 ml/kg; (3) pressure-controlled ventilation with VT of 12 ml/kg; (4) pressure-controlled ventilation with VT of 6 ml/kg; (5) inspired oxygen fraction of 1.0; and (6) high positive end-expiratory pressure. Then, they changed the maximum or minimum length of rebreathing loop with VT set at 12 ml/kg. After establishing steady-state conditions (15 min), they measured cardiac output using CO2 rebreathing and thermodilution via a pulmonary artery catheter. Finally, they repeated the measurements during pressure support ventilation, when the patients had restored spontaneous breathing. The correlation between two methods was evaluated with linear regression and Bland-Altman analysis.

Results: When VT was set at 12 ml/kg, cardiac output with the CO2 rebreathing technique correlated moderately with that measured by thermodilution (y = 1.02x, R = 0.63; bias, 0.28 l/min; limits of agreement, -1.78 to +2.34 l/min), regardless of ventilatory mode, oxygen concentration, or positive end-expiratory pressure. However, at a lower VT of 6 ml/kg, the CO2 rebreathing technique underestimated cardiac out-put compared with thermodilution (y = 0.70x; R = 0.70; bias, -1.66 l/min; limits of agreement, -3.90 to +0.58 l/min). When the loop was fully retracted, the CO2 rebreathing technique overestimated cardiac output.     

Clinicopathological prognostic factors and impact of surgical treatment of mass-forming intrahepatic cholangiocarcinoma

The clinicopathological characteristics relevant to prognosis after surgical treatment of intrahepatic cholangiocarcinoma (ICC) remain unclear. In this study, the clinicopathological features of 19 patients with mass-forming ICC, the most common form of the disease, were reviewed to analyze prognostic determinants. Two or more segmentectomies of the liver with systematic lymphadenectomy were performed in 18 patients. Resection of the extrahepatic bile duct was performed in 14 patients, and reconstruction of the portal vein was accomplished in 5 patients. Stage IVA or IVB tumors were seen in 13 patients, and lymph node (LN) metastasis was present in 14 patients. The estimated 5-year survival rate after surgery for mass-forming ICC was 28%, with median survival time of 18 months. In univariate analysis, five variables were determined to be significantly correlated with poor survival of patients with mass-forming ICC after surgery. These variables include mass-forming ICC with periductal infiltration, perineural invasion, portal vein invasion, presence of intrahepatic metastasis, and two or more LN metastases. Survival rates of 5 patients without LN metastasis and 6 patients with a single LN metastasis were 80% and 33% at 5 years, respectively, while 8 patients with two or more LN metastasis failed to survive beyond 2 years. Multivariate analysis revealed the presence of intrahepatic metastasis to be an independent prognostic factor of poor survival. Hepatectomy with resection of the extrahepatic bile duct and systematic lymphadenectomy yields a good chance for prolonged survival for patients with mass-forming ICC when the lesion is singular and LN metastasis is limited to a regional LN. Because the presence of intrahepatic metastasis was closely related to a poor prognosis in patients with mass-forming ICC, efficacious chemotherapy would be needed to control development of the lesion.     

Complete paralysis of the quadriceps muscle caused by traumatic iliacus hematoma: a case report

 A 15-year-old girl who developed traumatic iliacus hematoma and complete paralysis of the quadriceps muscle is reported. The current case and literature review revealed that incomplete quadriceps paralysis associated with traumatic iliacus hematoma is likely to progress to complete paralysis in days or weeks as a result of increased intracompartmental pressure. However, surgical decompression of the femoral nerve could produce good results even in patients who have complete quadriceps paralysis preoperatively. Received: April 9, 2002 / Accepted: June 28, 2002 Offprint requests to: K. Tamai