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Male NZW/BXSB.Yaa (W/B) mice express two copies of TLR7 and develop pathogenic autoantibodies whereas females with only one copy of TLR7 have attenuated disease. Our goal was to analyze the regulation of the autoantibody response in male and female W/B mice bearing the autoreactive site-directed heavy chain transgene 3H9. Serum anti-dsDNA antibodies appeared in males at 12 weeks and most had high titer IgG anti-dsDNA and anti-cardiolipin antibodies and developed >300mg/dl proteinuria by 8 months. Females had only low titer IgG anti-CL antibodies and none developed proteinuria by 1 year. Males had a smaller marginal zone (MZ) than females with a repertoire that was distinct from the follicular repertoire, indicating that the loss of MZ B cells was not due to diversion to the follicular compartment. Vk5-43 and Vk5-48, that were rare in the naïve repertoire, were markedly overrepresented in the GC repertoire of both males and females but the VJ junctions differed between males and females with higher affinity autoreactive B cells being selected into the GCs of males. Administration of IFNα to females induced anti-cardiolipin and anti-DNA autoantibodies and proteinuria and was associated with a male pattern of junctional diversity in Vk5-43 and Vk5-48. Our studies are consistent with the hypothesis that presence of the Yaa locus, that includes an extra copy of Tlr7, or administration of exogenous IFNα relaxes the stringency for selection in the germinal centers resulting in increased autoreactivity of the antigen driven B cell repertoire.

Lingual adenocarcinomas (ADC), either primary or metastatic to the tongue are extraordinarily rare neoplasms. Primary lingual adenocarcinomas are primarily of minor salivary gland origin. Two cases of primary colonic-type adenocarcinomas of the base of the tongue were recently reported for the first time in the English literature. We present an additional case of lingual intestinaltype adenocarcinoma with mucinous features that occurred in association with cervical node metastasis and discuss the clinicopathologic features and histogenetic aspects of this rare entity.

BAFF inhibition is a new B cell-directed therapeutic strategy for autoimmune disease. Our purpose was to analyze the effect of BAFF/APRIL availability on the naive and Ag-activated B cell repertoires in systemic lupus erythematosus, using the autoreactive germline D42 H chain (glD42H) site-directed transgenic NZB/W mouse. In this article, we show that the naive Vκ repertoire in both young and diseased glD42H NZB/W mice is dominated by five L chains that confer no or low-affinity polyreactivity. In contrast, glD42H B cells expressing L chains that confer high-affinity autoreactivity are mostly deleted before the mature B cell stage, but are positively selected and expanded in the germinal centers (GCs) as the mice age. Of these, the most abundant is VκRF (Vκ16-104*01), which is expressed by almost all IgG anti-DNA hybridomas derived from the glD42H mouse. Competition with nonautoreactive B cells or BAFF/APRIL inhibition significantly inhibited selection of glD42H B cells at the late transitional stage, with only subtle effects on the glD42H-associated L chain repertoire. However, glD42H/VκRF-encoded B cells were still vastly overrepresented in the GC, and serum IgG anti-DNA Abs arose with only a slight delay. Thus, although BAFF/APRIL inhibition increases the stringency of negative selection of the naive autoreactive B cell repertoire in NZB/W mice, it does not correct the major breach in B cell tolerance that occurs at the GC checkpoint.

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Objectives We compared the clinicopathologic features, clinical management, and outcomes of human epidermal growth factor receptor 2 (HER2)–expressing and nonexpressing microinvasive breast carcinomas (MiBC) to explore the significance of HER2 in MiBC. Methods Clinicopathologic and follow-up information of cases with final diagnosis of MiBC with known HER2 status between 2007 and 2019 were analyzed. Results Nineteen (41.3%) HER2-positive (HER2+) and 27 (58.7%) HER2-negative (HER2−) MiBCs were identified. HER2 positivity was likely to be associated with high nuclear grade, presence of tumor-infiltrating lymphocytes, hormonal receptor negativity, and increased Ki-67 in both microinvasive and associated in situ carcinomas. Nodal metastases were found in 2 ER+/HER2− cases (5.3%). One HER2+ case was found to have isolated tumor cells in the axillary node. The majority of patients with HER2+ MiBCs (76.5%) did not receive HER2-targeted therapy. All patients with available follow-up were alive without recurrence or distant metastasis, with a median follow-up of 38 months. Conclusions Similar to the larger size of invasive breast carcinomas, HER2 positivity is associated with high-grade morphologic features in MiBCs. However, HER2 overexpression in MiBCs does not appear to be associated with nodal metastasis or worse outcome in our study cohort. The role of HER2-targeted therapy in this clinical setting merits additional study.

Recent preclinical and clinical trials have demonstrated the therapeutic potential of T lymphocytes redirected with genetically engineered T-cell receptor (TCR) surrogates against infected, cancerous, or autoreactive cells. These surrogate TCRs link a ligand-recognition domain to signaling regions from the TCR. We previously compared the function of surrogate TCRs that include TCR or TCR and CD28 signaling regions. We found that primary murine T cells modified to specifically target K b -restricted CD8 ؉ T cells using either K b -or K b -CD28-receptors had similar functional activities, although the CD28-receptor showed a 2-fold to 4-fold decreased expression. We have now identified a previously unrecognized dileucine motif in the murine CD28 signaling domain that accounts for this reduced expression. Inactivation of this motif increased chimeric receptor surface expression 2-to 5-fold. T cells expressing the dileucinemutated CD28-chimeric receptor demonstrated enhanced proliferation, cytokine production, and cytolytic activities. Further, cells expressing this dileucine-mutated receptor were highly effective in eliminating antigen-specific CD8 ؉ T lymphocytes in vivo. These results therefore identify a critical motif limiting the function of receptor-modified T lymphocytes, demonstrate that inactivation of this motif enhances chimeric receptor function, and illustrate a potential novel application of receptor-modified T lymphocytes in the induction of immune tolerance. IntroductionT cells transgenically modified to express genetically engineered chimeric receptors (receptor-modified T cells [RMTCs]) can target antigens not normally recognized by the immune system. [1][2][3] The chimeric receptors that redirect these RMTCs against their targets functionally substitute for the T-cell receptor (TCR). They recognize target antigen through an extracellular antigen-recognition domain, such as a single-chain Fv fragment, and signal the RMTCs through a linked TCR-derived signal transduction domain, typically from the TCR chain. RMTCs have shown therapeutic potency in model systems, selectively targeting cancerous, infected, and autoreactive T cells, and have not shown significant toxicity in phase 1 clinical trials. [4][5][6][7] Although engineered surrogate receptors can redirect therapeutic T cells, their effectiveness in doing this may be limited by the limited signal they can transduce. Coreceptor and costimulatory signals, normally provided to T cells when they interact with a "professional" antigen-presenting cell, will often not be available to RMTCs engaging a ligand on a tumor or other target cell with a chimeric receptor. 8,9 These signals can promote T-cell survival, proliferation, and effector function and may therefore be critical for RMTC function. To overcome this limitation, we and others have developed single-chain chimeric receptors that incorporate modular signal transduction subunits derived from the TCR, costimulatory, and/or coreceptor molecules. 5,10-13 The receptor structure most commonly analy...

Background: Spindle cell neoplasms of the gastrointestinal (GI) tract constitute a wide group of lesions that may raise diagnostic difficulties on hematoxylin-eosin-stained slides. Appropriate endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) technique with sufficient cell block material for immunohistochemistry (IHC) can lead to accurate diagnosis.Methods: This is a retrospective study of 29 cases obtained from our institution's records over a five-year period (2011)(2012)(2013)(2014)(2015). Cytomorphology, histology (when available), IHC, FNA procedure details, imaging characteristics, and clinical history were reviewed. Rapid onsite evaluation (ROSE) was used in all cases. Cytologic samples were correlated with surgical pathology resection specimens when available.Results: Eighteen GI stromal tumors, six leiomyomas, two schwannomas, and one granular cell tumor were analyzed; two cases were not amenable for a definitive diagnosis: one showed fragments of smooth muscle not otherwise specified (smooth muscle vs. leiomyoma) and the other one was insufficient for diagnosis. Locations included stomach, esophagus, duodenum, and colon. EUS-FNA was performed with different gauge needles. Total number of passes ranged between two and nine. We found no evidence that larger-sized needles are superior in procuring adequate lesional tissue. Cell block material was stained with various antibodies. Fourteen surgical resection specimens available showed 100% correlation between cytology and histology. None of the neoplasms recurred until now; one patient succumbed to known esophageal squamous cell carcinoma.Conclusion: FNA is a pivotal and inexpensive method for rapid evaluation of GI spindle cell tumors and should be used widely in the attempt to avoid unnecessary surgery. Size of needle used for EUS-FNA does not seem to influence the yield of lesional tissue; rather, ROSE can guide the number of passes and subsequently lead to an adequate cell block. K E Y W O R D S endoscopic ultrasound-guided fine-needle aspiration, gastrointestinal leiomyoma, gastrointestinal stromal tumor, needle gauge, passes