Heizaburo Yamamoto

A Phase I-II Study of α-Galactosylceramide-Pulsed IL-2/GM-CSF-Cultured Peripheral Blood Mononuclear Cells in Patients with Advanced and Recurrent Non-Small Cell Lung Cancer

To evaluate the safety, immune responses, and antitumor responses after the administration of α-galactosylceramide (αGalCer) KRN7000-pulsed PBMC cultured with IL-2 and GM-CSF (IL-2/GM-CSF-cultured PBMCs), a phase I-II study in patients with non-small cell lung cancer was conducted. Patients with advanced non-small cell lung cancer or recurrent lung cancer refractory to the standard therapy were eligible. αGalCer-pulsed IL-2/GM-CSF-cultured PBMCs (1 × 109/m2) were i.v. administered four times. Immune responses were monitored weekly. Twenty-three patients were enrolled in this study and 17 cases (73.9%) completed. No severe adverse event related to the treatment was observed. After the injection of αGalCer-pulsed IL-2/GM-CSF-cultured PBMCs, an increased number of IFN-γ-producing cells in the peripheral blood were detected in 10 patients (58.8%). Five cases remained as stable disease, and the remaining 12 cases were evaluated as progressive disease. The estimated median survival time (MST) of the 17 cases was 18.6 mo (range, 3.8 to 36.3 mo). Ten patients who displayed increased IFN-γ-producing cells (≥2-fold) showed prolonged MST (31.9 mo; range, 14.5 to 36.3 mo) as compared with poor-responder patients (n = 7) MST (9.7 mo; range, 3.8 to 25.0 mo) (log-rank test, p = 0.0015). The administration of αGalCer-pulsed IL-2/GM-CSF-cultured PBMCs was well tolerated and was accompanied by the successful induction of NKT cell-dependent immune responses. The increased IFN-γ-producing cells that result from αGalCer stimulation in PBMCs were significantly associated with prolonged MST. These results are encouraging and warrant further evaluation for survival benefit of this immunotherapy.

Combination therapy of in vitro‐expanded natural killer T cells and α‐galactosylceramide‐pulsed antigen‐presenting cells in patients with recurrent head and neck carcinoma

The aim of this clinical trial was to investigate the feasibility of intra‐arterial infusion of in vitro‐expanded Vα24 natural killer T (NKT) cells combined with submucosal injection of α‐galactosylceramide (KRN7000; αGalCer)‐pulsed antigen‐presenting cells (APC). A phase I clinical study was carried out in patients with head and neck squamous cell carcinoma (HNSCC). Patients with locally recurrent HNSCC refractory to standard therapy were eligible. Eight patients received super‐selective transcatheter intra‐arterial infusion of activated Vα24 NKT cells into tumor‐feeding arteries and nasal submucosal injections of αGalCer‐pulsed APC twice with a 1‐week interval. Vα24 NKT cell‐specific immune responses, safety, and antitumor effects were evaluated. The number of Vα24 NKT cells and interferon‐γ‐producing cells in peripheral blood mononuclear cells increased in seven out of eight patients enrolled. Grade 3 toxicity with a pharyngocutaneous fistula related to local tumor reduction was observed in one patient and mild adverse events with grade 1–2 symptoms occurred in seven patients. Regarding the clinical responses, three cases exhibited a partial but significant response, four were classified as stable disease, and one patient continued to develop progressive disease. The use of the intra‐arterial infusion of activated Vα24 NKT cells and the submucosal injection of αGalCer‐pulsed APC has been shown to induce significant antitumor immunity and had beneficial clinical effects in the management of advanced HNSCC. The use of such therapeutic modalities may be helpful in the management of tumors and therefore needs to be explored in further detail. The clinical trial registration number was UMIN000000722. (Cancer Sci 2009; 100: 1092–1098)

The Interleukin-33-p38 Kinase Axis Confers Memory T Helper 2 Cell Pathogenicity in the Airway

Memory CD4(+) T helper (Th) cells provide long-term protection against pathogens and are essential for the development of vaccines; however, some antigen-specific memory Th cells also drive immune-related pathology, including asthma. The mechanisms regulating the pathogenicity of memory Th cells remain poorly understood. We found that interleukin-33 (IL-33)-ST2 signals selectively licensed memory Th2 cells to induce allergic airway inflammation via production of IL-5 and that the p38 MAP kinase pathway was a central downstream target of IL-33-ST2 in memory Th2 cells. In addition, we found that IL-33 induced upregulation of IL-5 by memory CD4(+) T cells isolated from nasal polyps of patients with eosinophilic chronic rhinosinusitis. Thus, IL-33-ST2-p38 signaling appears to directly instruct pathogenic memory Th2 cells to produce IL-5 and induce eosinophilic inflammation.

Present Situation of Cedar Pollinosis in Japan and its Immune Responses

Recent observations have suggested significant worldwide increase in the prevalence of allergic rhinitis and cedar pollinosis. In Japan, Japanese cedar (Cryptometria japonica) and Japanese cypress (Chamaecyparis obtusa) pollens are considered to be the major unique allergens and their extent of dispersal is quite large, travelling more than 100km and thus causing serious pollinosis. Cedar pollinosis is a typical type 1 allergic disease by an adaptive immune response that occurs through the induction of allergen-specific effector T cells from naïve T cells. We examined the number of Japanese cedar pollen specific memory Th cells in the peripheral blood of the patients and found that the cedar pollen specific IL-4-producing Th2 memory cells increased during the pollen season and decreased during the off-season. However, more than 60% of the cedar-specific memory Th2 cells survived up to 8 months after the pollen season. Natural killer T(NKT) cells represent a unique lymphocyte subpopulation and their activity is not restricted to MHC antigens. NKT cells play an important role in innate immunity, however, the participation in development of allergic rhinitis could not be clarified.

Thy1+IL-7+ lymphatic endothelial cells in iBALT provide a survival niche for memory T-helper cells in allergic airway inflammation

Significance A substantial proportion of people have intractable chronic allergic diseases for which no curative treatment exists. A clear understanding of how these allergic diseases develop and persist is lacking. Here, unique ectopic lymphoid-like structures called inducible bronchus-associated lymphoid tissue were found to be formed during chronic airway inflammation, and were critical in persistent inflammation. In addition, we identified a Thy1+IL-7+IL-33+ subset of lymphatic endothelial cells (LECs) that support the maintenance of memory-type pathogenic T helper 2 (Tpath2) cells. A similar population of IL-7+IL-33+ LECs was found in nasal polyps of patients with eosinophilic chronic rhinosinusitis. Thus, we revealed that Thy1+IL-7–producing LECs control chronic allergic airway inflammation by supporting memory-type Tpath2 cells in human and mouse systems. Memory CD4+ T helper (Th) cells are central to long-term protection against pathogens, but they can also be pathogenic and drive chronic inflammatory disorders. How these pathogenic memory Th cells are maintained, particularly at sites of local inflammation, remains unclear. We found that ectopic lymphoid-like structures called inducible bronchus-associated lymphoid tissue (iBALT) are formed during chronic allergic inflammation in the lung, and that memory-type pathogenic Th2 (Tpath2) cells capable of driving allergic inflammation are maintained within the iBALT structures. The maintenance of memory Th2 cells within iBALT is supported by Thy1+IL-7–producing lymphatic endothelial cells (LECs). The Thy1+IL-7–producing LECs express IL-33 and T-cell–attracting chemokines CCL21 and CCL19. Moreover, ectopic lymphoid structures consisting of memory CD4+ T cells and IL-7+IL-33+ LECs were found in nasal polyps of patients with eosinophilic chronic rhinosinusitis. Thus, Thy1+IL-7–producing LECs control chronic allergic airway inflammation by providing a survival niche for memory-type Tpath2 cells.

Interleukin-25 and mucosal T cells in noneosinophilic and eosinophilic chronic rhinosinusitis

BACKGROUND Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous disease of uncertain pathogenesis. Memory T cells acquire additional functions during the secondary response and play important roles in chronic inflammation. OBJECTIVE To investigate characteristics of tissue memory CD4(+) T cells obtained from patients with noneosinophilic CRSwNP (NECRS) and eosinophilic CRSwNP (ECRS) by focusing on the influence of interleukin (IL)-25. METHODS Pro-allergic cytokines in tissue homogenates were measured using enzyme-linked immunosorbent assays. NP mononuclear cells and CD4(+) T cells were isolated from NPs from patients with CRSwNP. Cytokine expression and CD4(+) T-cell subpopulations were analyzed using enzyme-linked immunosorbent assay, flow cytometry, and real-time polymerase chain reaction. RESULTS The IL-25 level in NPs increased in patients with ECRS. IL-5 and IL-9 mRNA levels expressed by tissue CD4(+) T cells were significantly elevated in patients with ECRS. Most infiltrating CD4(+) T cells in ECRS and NECRS expressed CD45RO; however, regardless of the atopic status, high IL-17RB levels were detected in CD4(+) T cells from patients with ECRS. IL-17RB mRNA levels expressed by tissue CD4(+) T cells significantly correlated with the number of eosinophils in NPs. Elevation of IL-5 and IL-9 production was found in NP mononuclear cells from patients with ECRS, but not in those from patients with NECRS, by stimulation with IL-25 under T-cell receptor stimulation. CONCLUSION Interleukin-25 and a subpopulation of tissue T-helper type 2 and 9 cells that express increased IL-17RB levels could contribute to infiltration of eosinophils in NPs and could have produced the pathologic difference between NECRS and ECRS.

Randomized double-blind study of prophylactic treatment with an antihistamine for seasonal allergic rhinitis.

Background: The efficacy of prophylactic treatment before the start of pollen dispersal for prevention of aggravation of symptoms is unclear. The aim of the present study was to examine the efficacy of prophylactic treatment with an antihistamine for seasonal allergic rhinitis (SAR) using an environmental challenge chamber (ECC). Methods: The study was performed in a randomized double-blind manner with a 3-way crossover design. The subjects were 50 patients with SAR caused by Japanese cedar pollen who were randomized for treatment with levocetirizine hydrochloride 5 mg (Xyzal®) or placebo as follows: administration of placebo for 8 days (treatment A), single administration of levocetirizine on day 8 after placebo for 7 days (treatment B) or administration of levocetirizine for 8 days (treatment C). Efficacy in each treatment arm was evaluated based on cedar pollen exposure for 3 h on day 9 in an ECC, following 1-hour exposure on day 8. The primary endpoint was the total nasal symptom score for 12 h on day 9. Other nasal and ocular symptoms were secondary endpoints. Results: The evaluation was performed in 45 subjects. The total nasal symptom score on day 9 was significantly lower with treatment B compared with treatment A. Treatment C did not show superior efficacy compared with treatment B. Conclusions: Our results suggest that early intervention with levocetirizine soon after onset of symptoms may attenuate these symptoms as effectively as prophylactic treatment before pollen dispersal. These results are important from the perspective of patient convenience and reduction of medical costs.

Comparison of nasal steroid with antihistamine in prophylactic treatment against pollinosis using an environmental challenge chamber.

Environmental challenge chambers (ECC) have been used to expose people to pollen allergens within a stable atmosphere and to examine the efficacy of treatment. Although pollinosis is one of the typical IgE-mediated type I allergic diseases, allergic inflammation is thought to contribute to the fundamental pathogenesis and prophylactic treatment may reduce exacerbations of pollinosis. The purpose of this study was to compare the efficacy of prophylactic treatment with nasal steroid (mometasone furoate nasal spray) or an antihistamine (fexofenadine) in the control of cedar pollinosis using the ECC. In a randomized, double-blind two-way crossover study, 48 patients received nasal steroid or antihistamine for 7 consecutive days (days 1-7). On day 8, patients were exposed to cedar pollen (8000 grains/m(3)) in the ECC for 3 hours. Nasal symptoms induced by pollen exposure were assessed. Total nasal symptom scores (TNSSs) during the exposure in the ECC were not significantly different between the antihistamine and the nasal steroid groups. Nasal symptoms induced by pollen exposure using the ECC persisted for up to 3 days. TNSSs after pollen exposure on days 8-11 were significantly lower in the nasal steroid group compared with the antihistamine group. Prophylactic treatment with nasal steroid is more effective than antihistamine against pollinosis, particularly in the late phase. Clinical trial registration JAPIC CTI 101182 (www.clinicaltrials.jp/user/ctiMain_e.jsp).

Myosin light chains 9 and 12 are functional ligands for CD69 that regulate airway inflammation

CD69 on activated T cells interacts with Myl9/12 expressed in inflamed airways, establishing tissue inflammation. Breathing down asthma’s neck Worldwide increases in the prevalence of chronic inflammatory diseases such as asthma highlight the need for new targeted therapies. CD4+ T cells that express the activation marker CD69 contribute to the pathogenesis of some types of asthma, but the exact role of CD69 remains unclear. Hayashizaki et al. reported that myosin light chain (Myl) 9 and Myl12 are functional ligands for CD69. Myl9/12 expression was increased in inflamed mouse airways and in patients with eosinophilic chronic rhinosinusitis. These data suggest that CD69-Myl9/12 interaction is involved in recruiting activated cells to inflamed tissues. Indeed, blocking CD69-Myl9/12 interaction in two different mouse models decreased allergic airway inflammation, suggesting that targeting CD69-Myl9/12 interaction could treat chronic inflammatory diseases. Recent decades have witnessed a rapid worldwide increase in chronic inflammatory disorders such as asthma. CD4+ T helper 2 cells play critical roles in the pathogenesis of allergic airway inflammation, and CD69 expression on activated CD4 T cells is required to induce allergic inflammation in tissues. However, how CD69 mechanistically controls allergic inflammation remains poorly defined. In lymphoid tissues, CD69 regulates cellular retention through inhibition of S1P1 expression and requires no specific ligands to function. In contrast, we show herein that myosin light chain (Myl) 9 and Myl12 are new functional ligands for CD69. Blockade of CD69-Myl9/12 interaction ameliorates allergic airway inflammation in ovalbumin-induced and house dust mite–induced mouse models of asthma. Within the inflamed mouse airways, we found that the expression of Myl9/12 was increased and that platelet-derived Myl9/12 localized to the luminal surface of blood vessels and formed intravascular net-like structures. Analysis of nasal polyps of eosinophilic chronic rhinosinusitis patients revealed that Myl9/12 expression was increased in inflammatory lesions and was distributed within net-like structures in the intravascular space. In addition, we detected Myl9/12 in perivascular spaces where many CD69+ cells were positioned within Myl9/12 structures. Thus, CD69-Myl9/12 interaction is a key event in the recruitment of activated CD69+ T cells to inflamed tissues and could be a therapeutic target for intractable airway inflammatory diseases.

Characteristics of the Chiba Environmental Challenge Chamber

BACKGROUND An environmental challenge chamber (ECC), which we refer to as the α-chamber, was built at Chiba University in 2008. The aim of this study was to validate the functionality of the ECC. METHODS The stability of the pollen distribution and concentration in the ECC and symptoms of patients with Japanese cedar pollinosis induced by cedar pollen exposure were examined. Carryover effects of symptoms induced by different exposure protocols and correlations between symptoms induced in the ECC and those in the natural cedar pollen season were also determined. All the studies using the α-chamber were conducted out of the cedar pollen season. RESULTS The severity of symptoms in the chamber reached a peak about 2 hours after the start of pollen exposure and plateaued thereafter. After subjects left the chamber, the symptoms persisted for several days. There was no significant difference between the severity of symptoms at exposure levels of 8000 and 12000 grains/m3. The symptoms were significantly increased by exposure for 3 consecutive days; however, there were no carryover effects in a study performed with a two-week interval. The total nasal symptom score (TNSS) in the natural pollen season showed a weak correlation with the mean TNSS on the day of exposure and the following 3 days. Symptoms in the ECC also had weak correlations with those in the early natural pollen season. CONCLUSIONS The ECC under well-controlled conditions is suitable for clinical studies and might accelerate development of treatment for seasonal allergic rhinitis. A complete evaluation requires inclusion of the persistent reaction after subjects leave the ECC.