Interstitial Pneumonia Associated with Nodal T-follicular Helper Cell Lymphoma: A Case Report.

Nodal T-follicular helper cell lymphoma (nTFHL), a hematologic neoplasm originating from T-follicular helper (TFH) cells, occasionally presents with pulmonary radiographic abnormalities, without neoplastic cellular infiltration. However, the precise mechanisms underlying non-neoplastic pulmonary opacities in patients with nTFHL remain unclear. Previous reports have shown that TFH cell abnormalities are associated with collagen disease and interstitial pneumonia with autoimmune features (IPAF). We herein report a patient with nTFHL accompanied by interstitial pneumonia diagnosed via lung and lymph node biopsies. These findings suggest the need to rule out nTFHL before diagnosing IPAF.

C-type Lectin Mincle Recognizes Glucosyl-diacylglycerol of Streptococcus pneumoniae and Plays a Protective Role in Pneumococcal Pneumonia.

Among various innate immune receptor families, the role of C-type lectin receptors (CLRs) in lung protective immunity against Streptococcus pneumoniae (S. pneumoniae) is not fully defined. We here show that Mincle gene expression was induced in alveolar macrophages and neutrophils in bronchoalveolar lavage fluids of mice and patients with pneumococcal pneumonia. Moreover, S. pneumoniae directly triggered Mincle reporter cell activation in vitro via its glycolipid glucosyl-diacylglycerol (Glc-DAG), which was identified as the ligand recognized by Mincle. Purified Glc-DAG triggered Mincle reporter cell activation and stimulated inflammatory cytokine release by human alveolar macrophages and alveolar macrophages from WT but not Mincle KO mice. Mincle deficiency led to increased bacterial loads and decreased survival together with strongly dysregulated cytokine responses in mice challenged with focal pneumonia inducing S. pneumoniae, all of which was normalized in Mincle KO mice reconstituted with a WT hematopoietic system. In conclusion, the Mincle-Glc-DAG axis is a hitherto unrecognized element of lung protective immunity against focal pneumonia induced by S. pneumoniae.

Successful treatment with alectinib after crizotinib-induced esophageal ulceration.

Crizotinib was the first clinically available inhibitor of the tyrosine kinase ALK, and next-generation ALK inhibitors, such as alectinib, are now under development. Although crizotinib is generally well tolerated, severe esophageal injury has been reported as a rare but serious adverse event of crizotinib therapy. We now describe the successful treatment with alectinib of a patient who developed crizotinib-induced esophageal ulceration.