Immune function in cyclophosphamide-treated mice is restored by the T-cell-tropic isoxazole derivative R-13

Abstract

Reconstitution of the immune function in chemotherapy patients will lead to decreases in post-operative complications. A preliminary investigation showed that an isoxazole derivative R-13 (3,5-dimethyl-isoxazole[5,4-e]8H-triazepin-4-one) hydrochloride, given in a single oral dose to normal mice, induced significant increases in the content of CD4⁺ cells in the spleens and lymph nodes. That observation prompted the authors to assess the immune reconstituting effects of R-13 in mice pre-treated with cyclophosphamide (CP). Mice were given intraperitoneally (IP) a sublethal dose of CP (200?mg/kg) and then R-13 (as 20?µg IP doses, every 3 days post-CP treatment). Control mice, not treated with CP, received R-13 or the vehicle (DMSO in appropriate dilution). Blood leukocyte and splenocyte numbers, blood cell type levels, splenocyte spontaneous and ConA-induced proliferation, and delayed-type hypersensitivity (DTH) to ovalbumin (OVA) were investigated on day 15 post-CP treatment and five R-13 doses. The humoral immune response (antibody-forming cell development to sheep erythrocytes) was measured 30 days post-CP treatment and 10 R-13 doses. In CP-treated mice, five dosings with R-13 led to increases in numbers of splenocytes and blood leukocytes, as well as in spontaneous and ConA-induced splenocyte proliferation, relative to levels in mice that received only CP 15 days earlier. Blood analysis revealed decreases in neutrophil and eosinophil contents and an increased appearance of lymphocyte immature forms in all mice that received the R-13. Both cell-mediated responses to OVA and humoral immune response to sheep erythrocytes in CP-treated hosts were restored. Based on the data here, it is concluded that R-13 may be of potential value for reconstitution of the immune function of chemotherapy patients.     

Cyclic adenosine monophosphate involvement in low-dose cyclophosphamide-reversed immune evasion in a mouse lymphoma model

Lymphoma cells mobilize many mechanisms to evade the immune system. There is substantial evidence that CD4⁺CD25⁺ regulatory T cells (Tregs) play a key role in the control of immune evasion. Tregs can transfer cyclic adenosine monophosphate (cAMP) to effector T cells, suggesting an association between Tregs'' immune-evasion role and the intracellular cAMP pathway. In this study, we used A20 B-cell lymphoma mice as aggressive tumor models to investigate the mechanism of the depletion of Tregs by low-dose cyclophosphamide (CY, 20 mg/kg). The tumor-bearing mice had longer survival times and slower tumor growth rates following treatment with CY, but its effects were temporary. Along with the depletion of Tregs by low-dose CY treatment, the expression of interleukin-2 (IL-2) in T effector cells increased, and intracellular cAMP concentrations in immune cells decreased. Our study demonstrates the ability of low-dose CY to reverse Tregs-mediated immune evasion in a mouse model. The changes in intracellular cAMP concentrations correlated with the upregulation of effector T cells and the downregulation of Tregs, indicating the close association of cAMP analogs and low-dose CY in the immune therapy of B-cell lymphoma.     

Wegener's granulomatosis: A challenging disease for otorhinolaryngologists

Conclusions

Diagnosis of Wegener's granulomatosis (WG) can be delayed because of its aspecific presenting symptoms. Detection of serum circulating antineutrophil cytoplasm antibodies (c-ANCAs), in combination with histology, permits one to identify WG at an early stage and to implement stage-adapted therapy. c-ANCA levels may also help to evaluate the response to medical therapy. Recently, the quality of life of WG patients has been improved by administering cotrimoxazole in order to prevent infections and recurrent diseases during the remission period.

Objective

WG is of special significance to the otorhinolaryngologist because it is often initially limited to the upper respiratory tract before becoming systemic. The aim of this paper was to describe a series of WG patients and underline the difficulties involved in diagnosing and treating this challenging disease.

Material and methods

This was a prospective study in 23 consecutive patients with head and neck manifestations of WG (17 systemic, 6 limited). Diagnosis was performed by means of both c-ANCAs detection using indirect immunofluorescence and histology in biopsy specimens. Treatment consisted of daily cyclophosphamide (CYC; 2?mg/kg/day) and glucocorticoids (prednisone; 1?mg/kg/day). If an improvement or toxic events occurred, CYC was discontinued and methotrexate was started. If, during remission of the disease, low serum c-ANCAs levels were detected, CYC was suspended and cotrimoxazole (1?g/day) was introduced.

Results

Serum c-ANCAs detection was positive for all patients. Biopsy was diagnostic from the beginning in 19/23 cases. The six patients with limited WG did not show a progression to systemic disease. Only 3 patients with a diagnosis of delayed systemic WG died, whereas 19/23 patients were alive with good control of relapses.     

Scleroderma lung disease: treatment with cyclophosphamide

Evaluation of: Tashkin, Elashoff, Clements PJ et al. Cyclophosphamide versus placebo in scleroderma lung disease. N. Engl. J. Med. 354(25), 2655–2666 (2006).

Interstitial lung disease has become one of the leading causes of morbidity and mortality in systemic sclerosis. Currently, there remains a void in proven effective treatment strategies to provide clinical benefit to affected patients. The article under evaluation pioneers the efforts of investigating oral cyclophosphamide in treating scleroderma lung disease by designing a prospective, double-blinded, placebo-controlled study examining the drug’s effect on outcome measures of forced vital capacity, patient subjective health assessment questionnaire disability scores, among others. We review the methods, results and overall conclusion of the study, which shows a significant, yet modest, result demonstrating the benefit of oral cyclophosphamide in the context of this disease setting. We conclude that although the study provides an excellent starting point for examining the efficacy of cyclophosphamide in certain forms of scleroderma lung disease, the study’s high drop-out rate, choice of forced vital capacity as a primary outcome, side-effect profile of the drug and overall significance of the results make the conclusions difficult to incorporate into clinical practice.     

Cyclophosphamide plus granulocyte‐colony stimulating factor for hematopoietic stem cell mobilization in patients with multiple myeloma

We retrospectively reviewed the results of cyclophosphamide (3 g/m²), doxorubicin and dexamethasone plus granulocyte‐colony stimulating factor (G‐CSF) (ID‐CY/DOX group), low‐dose cyclophosphamide (2 g/m²) plus G‐CSF (LD‐CY group) and G‐CSF alone (G‐CSF group) for stem cell mobilization in patients with multiple myeloma. A total of 89 patients with 93 mobilizations were included. Apheresis was started when total white blood cell (WBC) count >10 × 10⁹/L for ID‐CY/DOX and LD‐CY groups and after eight doses of G‐CSF (5 μg/kg twice daily) for G‐CSF group. For five mobilizations in ID‐CY/DOX group, the rate of successful mobilization (≥4.0 × 10⁶/kg CD34+ cells) was 80%. For 78 mobilizations in LD‐CY group, the successful rate was 80.8%. For 10 mobilizations in the G‐CSF group, the successful rate was 50%. The mean yield of CD34+ cells was higher in ID‐CY/DOX and LD‐CY groups as compared with that in G‐CSF group (P = 0.026 and 0.020, respectively). There was no difference in the yield of CD34+ cells between ID‐CY/DOX and LD‐CY groups (P = 0.831). After autologous stem cell transplantation, the days to neutrophil and platelet engraftment were similar in these three groups (P = 0.713 and 0.821, respectively). In conclusion, we observed that ID‐CY/DOX and LD‐CY plus G‐CSF for stem cell mobilization resulted in a higher successful rate and higher stem cell yields than G‐CSF alone and their engraftment time were similar. Total WBC count >10 × 10⁹/L can be used as a guide to start apheresis in CY‐based stem cell mobilization. J. Clin. Apheresis 31:423–428, 2016. © 2015 Wiley Periodicals, Inc.     

B cell and B cell-related pathways for novel cancer treatments

B cells are recognized as the main effector cells of humoral immunity which suppress tumor progression by secreting immunoglobulins, promoting T cell response, and killing cancer cells directly. Given these properties, their anti-tumor immune response in the tumor micro-environment (TME) is of great interest. Although T cell-related immune responses have become a therapeutic target with the introduction of immune checkpoint inhibitors, not all patients benefit from these treatments. B cell and B cell-related pathways (CCL19, −21/CCR7 axis and CXCL13/CXCR5 axis) play key roles in activating immune response through humoral immunity and local immune activation via tertiary lymphoid structure (TLS) formation. However they have some protumorigenic works in the TME. Thus, a better understanding of B cell and B cell-related pathways is necessary to develop effective cancer control. In this review, we summarize recent evidences regarding the roles of B cell and B cell-related pathways in the TME and immune response and discuss their potential roles for novel cancer treatment strategies.     

A CASE WITH ACUTE RENAL FAILURE COMPLICATED BY WALDENSTRÖM'S MACROGLOBULINEMIA AND CRYOGLOBULINEMIA

We encountered a 53-year-old man associated with acute renal failure caused by Waldenström's macroglobulinemia and type I cryoglobulinemia. Treatment with prednisolone and cyclophosphamide induced a rapid recovery from acute renal failure. Renal histology revealed endocapillary proliferation and lobular formation with scattered subendothelial, amorphous and periodic acid-Schiff (PAS)-positive materials in the glomerular capillaries which were positive for IgM on immunofluorescence study. Although the exact mechanism for pathophysiology of acute renal failure remains unknown, treatment with prednisolone and cyclophosphamide could induce a rapid recovery from acute renal failure accompanied by Waldenström's macroglobulinemia and type I cryoglobulinemia.     

SLE伴发月经不调的临床特征及与免疫抑制剂应用的关系

目的探讨系统性红斑狼疮（systemic lupus erythematosus；SLE）患者伴发月经不调的临床特征，及月经不调与系统性红斑狼疮病情以及应用激素、环磷酰胺等免疫抑制剂的相关性。方法收集并分析本院女性系统性红斑狼疮住院患者178例的临床资料，包括患者住院前应用免疫抑制剂情况，了解患者发病及病程中的月经情况。结果（1）系统性红斑狼疮伴发月经不调随着患者年龄增加比例增高；（2）系统性红斑狼疮伴发月经不调患者比例随着使用激素、环磷酰胺等免疫抑制剂增高，随着剂量的增加而增高。结论系统性红斑狼疮患者可出现疾病相关的月经不调，但更多的月经不调的发生与环磷酰胺等免疫抑制剂的应用密切相关。