Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening adverse drug reactions characterized by massive epidermal necrosis, in which the specific danger signals involved remain unclear. Here we show that blister cells from skin lesions of SJS-TEN primarily consist of cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells, and both blister fluids and cells were cytotoxic. Gene expression profiling identified granulysin as the most highly expressed cytotoxic molecule, confirmed by quantitative PCR and immunohistochemistry. Granulysin concentrations in the blister fluids were two to four orders of magnitude higher than perforin, granzyme B or soluble Fas ligand concentrations, and depleting granulysin reduced the cytotoxicity. Granulysin in the blister fluids was a 15-kDa secretory form, and injection of it into mouse skin resulted in features mimicking SJS-TEN. Our findings demonstrate that secretory granulysin is a key molecule responsible for the disseminated keratinocyte death in SJS-TEN and highlight a mechanism for CTL- or NK cell--mediated cytotoxicity that does not require direct cellular contact.

Ovulation is the strongest risk factor for ovarian high-grade serous carcinoma (HGSC) that largely originates from the fallopian tube fimbriae and always carries loss-of-function mutations of TP53 in both early and late lesions. Mature ovarian follicle contains high level of reactive oxygen species (ROS). When released from ovulation, follicular fluid (FF) bathes the fimbriae and may lead to DNA double-strand break (DSB) and neoplastic transformation. In this study, we examined the mutagenic and tumorigenic activities of human pre-ovulatory FFs. A subset (6/11) of FFs was found with high levels of ROS whereas the antioxidant capacities were indifferent. These ROS(high) FFs induced intracellular ROS and DSBs in the secretory cell population of fimbriae epithelium. When p53 and Rb were turned down, the FF-exposed secretory cells overcame apoptosis and expanded the population carrying ROS and DSB. The cancer initiation and promotion effects of FF were further recapitulated in Trp53 (-/-) mice. When introduced into the mammary fat pad, ROS(high) but not ROS(low) FFs induced early-onset B-cell lymphoma. Cotreatment with physiological concentration of melatonin, a potent antioxidant, ameliorated the mutagenic and tumorigenic effect of ROS(high) FF in vitro and in vivo. The study revealed ROS and mitogens in mature ovarian follicles could initiate the transformation of fimbria epithelium in the context of p53 loss and melatonin is a potent preventive agent.

The use of flow cytometric enumeration of blasts in bone marrow aspirates has been of limited value in situations where blood contamination of the specimen is present. Assessment of sequential pulls of bone marrow aspirates from the same patient show decreasing proportions of blasts that are detected in later specimens. To address this problem, the intensity of CD16 on maturing neutrophils was compared for bone marrow biopsies, peripheral blood, and bone marrow aspirates. A comparison between bone marrow biopsy and aspirate specimens from the same individuals showed similar proportions of neutrophils with mature phenotype in most, but not all pairs. Other cell populations (total mature lymphocytes, monocytes, neutrophils, and blasts) were also similar between the two specimen types, with one exception of a patient with myelodysplasia, exhibiting a unique blast population in the biopsy that was not evident in the aspirate. The proportion of mature myeloid cells expressing a mature neutrophil phenotype (high levels of CD16) was found to be 17% (± 6.7, n = 47) in trephine marrow biopsy specimens. In contrast, marrow aspirates contained more of the mature neutrophil phenotype (38% ± 16, n = 33) with about 1/3 of the aspirates indistinguishable from biopsies. Using a simple formula to normalize the aspirate specimens to the average neutrophil composition of marrow biopsies, it was possible to correct for the dilutional effect of added blood to both normal bone marrow aspirates and aspirates with elevated blast counts. These results suggest three alternative means of circumventing the problem of blood dilution of marrow aspirate specimens.

Fallopian tube fimbrial epithelium is considered to be the major site of origin of ovarian high-grade serous carcinoma, with p53 loss being the earliest and universal change. We previously reported that reactive oxygen species (

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