A chimeric antigen receptor-based cellular safeguard mechanism for selective in vivo depletion of engineered T cells

Adoptive immunotherapy based on chimeric antigen receptor (CAR)-engineered T cells has exhibited impressive clinical efficacy in treating B-cell malignancies. However, the potency of CAR-T cells carriethe potential for significant on-target/off-tumor toxicities when target antigens are shared with healthy cells, necessitating the development of complementary safety measures. In this context, there is a need to selectively eliminate therapeutically administered CAR-T cells, especially to revert long-term CAR-T cell-related side effects. To address this, we have developed an effective cellular-based safety mechanism to specifically target and eliminate the transferred CAR-T cells. As proof-of-principle, we have designed a secondary CAR (anti-CAR CAR) capable of recognizing a short peptide sequence (Strep-tag II) incorporated into the hinge domain of an anti-CD19 CAR. In in vitro experiments, these anti-CAR CAR-T cells have demonstrated antigen-specific cytokine release and cytotoxicity when co-cultured with anti-CD19 CAR-T cells. Moreover, in both immunocompromised and immunocompetent mice, we observed the successful depletion of anti-CD19 CAR-T cells when administered concurrently with anti-CAR CAR-T cells. We have also demonstrated the efficacy of this safeguard mechanism in a clinically relevant animal model of B-cell aplasia induced by CD19 CAR treatment, where this side effect was reversed upon anti-CAR CAR-T cells infusion. Notably, efficient B-cell recovery occurred even in the absence of any pre-conditioning regimens prior anti-CAR CAR-T cells transfer, thus enhancing its practical applicability. In summary, we developed a robust cellular safeguard system for selective in vivo elimination of engineered T cells, offering a promising solution to address CAR-T cell-related on-target/off-tumor toxicities.

Long-term persistence and functionality of adoptively transferred antigen-specific T cells with genetically ablated PD-1 expression

Engagement of the inhibitory T cell receptor programmed cell death protein 1 (PD-1) associates with dysfunctional states of pathogen- or tumor-specific T cells. Accordingly, systemic antibody-mediated blockade of PD-1 has become a central target for immunotherapies but is also associated with severe toxicities due to loss of peripheral tolerance. Therefore, selective ablation of PD-1 expression on adoptively transferred T cells through direct genetic knockout (KO) is currently being explored as an alternative therapeutic approach. However, since PD-1 might also be required for the regulation of physiological T cell function and differentiation, the suitability of PD-1 as an engineering target is controversial. In this study, we systematically investigated the maintenance of T cell functionality after CRISPR/Cas9-mediated PD-1 KO in vivo during and after acute and chronic antigen encounter. Under all tested conditions, PD-1 ablation preserved the persistence, differentiation, and memory formation of adoptively transferred receptor transgenic T cells. Functional PD-1 KO T cells expressing chimeric antigen receptors (CARs) targeting CD19 could be robustly detected for over 390 d in a syngeneic immunocompetent mouse model, in which constant antigen exposure was provided by continuous B cell renewal, representing the longest in vivo follow-up of CAR-T cells described to date. PD-1 KO CAR-T cells showed no evidence for malignant transformation during the entire observation period. Our data demonstrate that genetic ablation of PD-1 does not impair functionality and longevity of adoptively transferred T cells per se and therefore may be pursued more generally in engineered T cell-based immunotherapy to overcome a central immunosuppressive axis.

Comorbidity has no impact on eosinophil inflammation in the upper airways or on severity of the sinonasal disease in patients with nasal polyps

OBJECTIVE

The study was designed to determine whether there is an association between the comorbidity as atopy, bronchial asthma, aspirin intolerance and eosinophil infiltration of the upper airways, severity of the sinonasal disease and rate of revision sinus surgery in patients with nasal polyps.

MATERIAL AND METHODS

One hundred and fifty patients were enrolled in the prospective study. Differences in CT score, rate of revision surgery, concentration of eotaxin and eosinophil cationic protein in nasal lavage fluid (NALF) and distribution of eosinophils in NALF and nasal tissue in patients with chronic rhinosinusitis with nasal polyps (CRSwNP), chronic rhinosinusitis without nasal polyps (CRSsNP) and control group were investigated. We focused on the relationship between presence of comorbidity (atopy, bronchial asthma and aspirin intolerance) and severity of the disease, the need of revision surgery and markers of eosinophil inflammation in upper airways in patients with CRSwNP.

RESULTS

Patients with CRSwNP had more severe form of the sinonasal disease, higher rate of revision FESS and significant higher presence of markers of eosinophil inflammation in NALF and nasal tissue than patients with CRSsNP (P < 0.05). Atopic and non-atopic asthma as well as aspirin sensitivity significantly more often coexisted with CRSwNP. Comorbidity did not influence eosinophil infiltration or severity of the disease in patients with CRSwNP.

CONCLUSION

Presence of comorbidity (atopy, bronchial asthma and aspirin intolerance) has no impact on severity of the disease or eosinophil content in the upper airways in patients with CRSwNP.

Surfactant proteins A and D are related to severity of the disease, pathogenic bacteria and comorbidity in patients with chronic rhinosinusitis with and without nasal polyps

BACKGROUND

Surfactant proteins (SP) A and D play a critical role in the innate defence of respiratory mucosa. Although numerous studies have focused on the importance of surfactant in the lower airways, relatively little is known about its role in the upper respiratory system.

METHODS

The prospective study was conducted with 61 subjects divided into patients with chronic rhinosinusitis with nasal polyps (CRSwNP), with chronic rhinosinusitis without nasal polyps (CRSsNP) and healthy controls. SP-A and SP-D were detected in nasal lavage fluid (NALF) by ELISA and in nasal mucosa by immunohistochemical staining. Severity of the diseases assessed by preoperative CT score, presence of comorbidity (allergy and bronchial asthma) and bacterial culture from the middle nasal meatus was evaluated.

RESULTS

In nasal mucosa, SPs were localised in ciliated cells of the surface epithelium and serous acini of the submucosal glands. Stronger expression of SPs in submucosal glands was observed in CRSwNP and CRSsNP groups in comparison with controls. In patients with CRSsNP and more severe form of the disease, higher levels of SP-A and SP-D in NALF and stronger immunoreactivity of these proteins in nasal mucosa were detected. Identification of pathogenic bacteria was associated with higher levels of SP-A and SP-D in NALF and nasal mucosa in patients with CRSsNP and control group. Presence of allergy was associated with stronger expression of SP-A in submucosal glands in all CRS patients and with decreased levels of both SPs in NALF in CRSsNP patients.

CONCLUSIONS

Surfactant proteins A and D play an important role in innate host defence of upper respiratory tract. Different expression of these proteins in patients with chronic rhinosinusitis indicates possible novel target of therapy in these patients.

Basal Cell Adenoma of the Upper Lip

Basal cell adenoma is an uncommon type of monomorphous adenoma of the salivary gland. Its most frequent location is the parotid gland. Its recurrence rate and conversion to basal cell adenocarcinoma after inadequate surgical excision is high. We present a 68-year-old female patient with a basal cell adenoma of the upper lip arising from minor salivary gland.

Kuttner tumor

OBJECTIVE

Kuttner tumor or chronic sclerosing sialadenitis is a benign inflammatory condition of the salivary gland. Clinically, it produces a firm swelling of the gland and may be difficult to distinguish from neoplasia. This is an under-recognized entity in the surgical pathology and cytology literature. We describe our experience with Kuttner tumor.

METHODS

Retrospectively, we analyzed a group of 7 patients with chronic sclerosing sialadenitis treated from January 1999 to March 2010 at the Department of Otorhinolaryngology, FD Roosevelt Faculty Hospital in Banska Bystrica, Slovakia. The authors evaluated age and sex distribution, patient's history, diagnostic procedures, extent and success of surgical treatment and postoperative complications.

RESULTS

Four patients with chronic sclerosing sialadenitis were male and 3 were female. The mean age of patients was 55 years (ranging from 43 to 70 years). Submandibular gland was affected in 6 cases (85.7 %), involvement of both parotid glands was found in one patient (14.3 %). All patients in our study group were treated surgically. In 6 cases submandibular gland extirpation was performed via standard transcervical approach. Total parotidectomy with facial nerve preservation was realized in one patient with bilateral involvement of parotid glands.

CONCLUSION

Chronic sclerosing sialadenitis is a condition that is perhaps more common than thought but usually mis-recognised as it is only after excision of the gland that the correct diagnosis is made (Tab. 1, Ref. 17).

Combined AFM and STM measurements of a silicene sheet grown on the Ag(111) surface

In this paper, we present the first non-contact atomic force microscopy (nc-AFM) of a silicene on a silver (Ag) surface, obtained by combining non-contact atomic force microscopy and scanning tunneling microscopy (STM). STM images over large areas of silicene grown on the Ag(111) surface show both (√13 × √13)R13.9° and (4 × 4) superstructures. For the widely observed (4 × 4) structure, the observed nc-AFM image is very similar to the one recorded by STM. The structure resolved by nc-AFM is compatible with only one out of two silicon atoms being visible. This indicates unambiguously a strong buckling of the silicene honeycomb layer.

Surgical management of submandibulary gland diseases: ten years of experience

OBJECTIVE

The surgical management of submandibular gland diseases has always been a challenge because it carries a considerable risk of nerve injury. The aim of the study was to evaluate the history, diagnostic procedure, extent and success of the surgical treatment as well as possible complications in patients with submandibulary gland disorder.

METHODS

We carried out a retrospective analysis of 86 patients (42 males, 44 females) with submandibular gland disorder treated between 1999 and 2008 at the Department of Otorhinolaryngology, FD Roosevelt Faculty Hospital in Banska Bystrica, Slovakia. Average age of patients was 52.3 years (range 13-80 years).

RESULTS

All patients in our study were treated surgically with the use of standard transcervical approach. The most common indication for submandibulary gland extirpation was sialolithiasis (39.6%). 33.7% of all lesions were sialadenitis, and 26.7% were neoplasms. The morbidity of surgical treatment was low. Transient palsy of marginal mandibular nerve was observed to be the most common complication after the surgery (14%).

CONCLUSION

Surgical removal of entire submandibulary gland is a safe operation with a low rate of complications (Tab. 5, Fig. 1, Ref. 17).

Genome-wide analysis of rice (Oryza sativa L. subsp. japonica) TATA box and Y Patch promoter elements

The TATA box is one of the best characterized transcription factor binding sites. However, it is not a ubiquitous element of core promoters, and other sequence motifs such as Y Patches seem to play a major role in plants. Here, we present a first genome-wide computational analysis of the TATA box and Y Patch distribution in rice (Oryza sativa L. subsp. japonica) promoter sequences. Utilizing a probabilistic sequence model, we ascertain that only approximately 19% of rice genes possess the TATA box, but approximately 50% contain one or more Y Patches in their core promoters. By computational processing of identified elements, we generated extended TATA box and Y Patch nucleotide frequency matrices capable of predicting these motifs in plants with a high degree of confidence.

Complex surveillance of Streptococcus pyogenes V. Protective features complex surveillance of streptococcus of cell-mediated immunity against group a streptococci

Exoproducts of incubated white blood elements from persons hypersensitive to zymosan were found to promote the phagocytic activity of human microphages (and guinea pig macrophages) under conditions of a combined model of "MIF-opsonophagocytic test". The stimulation resulted in a bacteriostatic effect, was non-type-specific and improved microphage potential to inactivate streptococci opsonized with anti-M antibodies in low titre. The microphages pre-exposed to anti-M sera remained unaffected, the effect was non-species-specific and nontype-specific and the stimulation resulted from the action of albumin fraction exoproducts. This seems to suggest that human mediators (lymphokines) may promote the activity of phagocytes. The cell-mediated immunity appears thus to have protective features even in the case of streptococci which are the typical extracellular parasites. The drawbacks of the model used, which make it difficult to quantify the found mechanism under in vivo conditions, are discussed in detail.