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Clear cell sarcomas are rare tumours accounting for less than 1% of all soft tissue tumours. They are aggressive lesions with extremely poor prognosis. The clinical diagnosis of this tumour is challenging, requiring histopathologic examination for definite characterization. The treatment protocol for this tumour is not well-established, with most studies showing no clear cut role of chemoradiation. This is a case of clear cell sarcoma of soft tissue in a 57-year-old male who presented with a solid-cystic mass on the thigh and was diagnosed as hematoma clinicoradiologically. Post-operative residual tumour was treated successfully with radio/chemotherapy, in a manner similar to melanoma. This article, thus, also highlights the role of chemoradiation in the treatment of clear cell sarcoma, suggesting that it can be better treated like melanoma rather than like a soft tissue sarcoma.

SUMMARYChronic lymphocytic leukemia (CLL) patients have lower seroconversion rates and antibody titers following SARS-CoV-2 vaccination, but the reasons for this diminished response are poorly understood. Here, we studied humoral and cellular responses in 95 CLL patients and 30 healthy controls after two BNT162b2 or mRNA-2173 mRNA immunizations. We found that 42% of CLL vaccinees developed SARS-CoV-2-specific binding and neutralizing antibodies (NAbs), while 32% had no response. Interestingly, 26% were seropositive, but had no detectable NAbs, suggesting the maintenance of pre-existing endemic human coronavirus-specific antibodies that cross-react with the S2 domain of the SARS-CoV-2 spike. These individuals had more advanced disease. In treatment-naïve CLL patients, mRNA-2173 induced 12-fold higher NAb titers and 1.7-fold higher response rates than BNT162b2. These data reveal a graded loss of immune function, with pre-existing memory being preserved longer than the capacity to respond to new antigens, and identify mRNA-2173 as a superior vaccine for CLL patients.

Purpose: To study vessel density (VD) on Optical Coherence Tomography Angiography (OCTA) at choroid, chorio-capillaries (CC) & various retinal levels in normal population & various stages of dry AMD & how these changes progress with increase in severity of the disease. Methods: Prospective, observational , cross-sectional study done on 252 eyes of 132 patients presenting to tertiary care centre in Central India between February 2021 to January 2022. For study purpose, eyes were divided into 5 groups according to the size and number of the drusen, viz, Group 1: No AMD ( 50 years) , Group 3 : Early AMD and Group 4 : Intermediate AMD & Group 5 : Advanced AMD. In all eyes , VD was measured at choroid , CC, Deep capillary plexus (DCP) of retina & superficial capillary plexus (SCP) of retina. Results: There were total 61 males & 71 females in the study . The mean age in case cohort is 61.90 ± 7.97 years with 52 (51.48%) males and 49 (48.51%) females. At choroidal level, the mean vascular density differed significantly across diagnosis types in all the quadrants (p < 0.05). Similar was the observation at CC & DCP level. At SCP level, except in central quadrant, the differences for remaining quadrants were significant across the groups. At SCP & DCP increase in VD is seen in early AMD cohort compared to No AMD (> 50 years) cohort, which showed continuous reduction later in intermediate & advanced AMD cohort. Conclusion: With increase in the severity of disease, significant reduction in VD is also seen in retinal plexuses, along with the changes in choroid & CC. These VD maps may play a role as non-invasive biomarkers for healthy & diseased aging.

Despite decades of research, an effective HIV-1 vaccine remains elusive. Vaccine strategies leading to the generation of broadly neutralizing antibodies are likely needed to provide the best opportunity of generating a protective immune response against HIV-1.

Background Anal cancer is rare in the general population in both genders in the US, but an increased incidence of anal cáncer (AC) has been reported among people living with HIV-1 infection (PLWH) and little is known among the population in South US. Methods In a retrospective study design, electronic health records from 2006 to 2018 were reviewed in a HIV clinical cohort at the University of Alabama at Birmingham. Associations of demographic, sociodemographic, and HIV-clinical indicators were examined in univariate analyses between high-grade squamous intraepithelial lesions (HSIL) and AC cases and condition-free individuals. Factors for anal/rectal cytology screening tests among PLWH were also assessed over time. Ages at onset of anal cancer were compared with the general US population reported by the National Surveillance, Epidemiology, and End Results Program. Results A total of 79 anal HSIL (96% men) and 43 cancer (100% men) patients were observed along with 4367 HSIL/cancer-free patients (75.9% men). HSIL (P P Conclusion AC incidence among HIV-infected men was 161 times higher than general population with an earlier age of onset/diagnosis. Many patients with AC had missed screening opportunities that could potentially have captured neoplasia in pre-cancerous stages. AC-related screening guidelines need to be integrated into routine clinical care, especially among PLWH at highest risk such as MSM and those with lower CD4 counts.

To study the relevance of preoperative OCT predictors in large macular holes (MH) treated using the inverted ILM peel technique.Prospective study of 95 patients undergoing vitrectomy for large MH between January 2019 and December 2020 was performed by dividing the patients into groups depending on various quantitative parameters and indices of MH such as base diameter (BD), hole form factor (HFF), macular hole index (MHI), diameter hole index (DHI), and tractional hole index (THI) by using parameters such as minimal hole diameter, hole height, nasal and temporal arm lengths. Depending upon the duration of symptoms, patients were divided into three groups:3 months, 3-6 months, and6 months. Anatomical success rate, type of closure, and postoperative vision gain were analyzed in relation to the abovementioned diameters, indices, and duration to see if any significance existed.The mean age of patients included in the study was 60.48 ± 13.88 years, with female preponderance (males: females = 37:58). Change in logMAR was statistically significant individually with all studied parameters (P0.0001) without influence of size of hole and other indices. BD and DHI levels showed significant association with type of closure as indicated by P values of 0.017 and 0.048, respectively. Duration of symptoms showed no significance in terms of anatomical and functional success.OCT predictors of MH success seem to have lost relevance with inverted flap surgeries as 100% anatomical success is achieved with this technique, with 95.78% (91/95) achieving type 1 closure with statistically significant equivalent functional gain across the indices with no effect of duration of symptoms.

BackgroundNeonatal hyperbilirubinemia (NNH) is the most common clinical sign seen in neonatal practice. Kangaroo mother care (KMC), a new strategy has been tried for the management of hyperbilirubinemia.AimsTo evaluate the role of KMC for reduction of bilirubin and duration of phototherapy in term and preterm neonates.MethodThe literature search was done for various randomized control trials by searching the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, ongoing clinical trials and abstracts of conferences.ResultsThis review included five RCTs that fulfilled inclusion criteria. Out of five trials, two trials reported a significant reduction in bilirubin and three trials reported a significant reduction in duration of phototherapy.ConclusionKMC may be a novel strategy in the management of NNH. However, due to small sample size and heterogeneity between the trials, the current evidence is not sufficient. Hence, large trials with adequate sample sizes are needed.

Microbial infection is a major barrier to wound care and repair process of the cells. Various US-FDA-approved drugs and surgical procedures have been used for wound healing progression. However, th...

Background PCV13 (conjugated polysaccharide) and PPSV23 (polysaccharide only) are two licensed vaccines targeting S. pneumoniae. The role of CD4 T-cell responses in pneumococcal vaccines among healthy participants and their impact on antibodies is not yet known. Methods Ten adults (5 old and 5 young) received PCV13 (prime) and a year later PPSV23 (boost). Blood samples were collected prior to and multiple time points after vaccination. CD4 T cells responding to CRM197, polysaccharide (PS), CRM197 conjugated polysaccharide (CPS), PCV13 and PPSV23 vaccines were measured by flow cytometry. Serum antibodies were analyzed via multiplex opsonophagocytosis (MOPA) and pneumococcal IgG assays. Results Vaccine-specific CD4 T cells were induced in all ten vaccinees post PCV13. Older vaccinees mounted higher peak responses and those specific for PCV13 and conjugated PS-1 were more polyfunctional compared to the younger group. Vaccine-elicited peripheral T follicular helper (Tfh) cells were only detected in the younger group who also exhibited a higher fold change in OPA titers post both vaccines. Importantly, Tfh cells following PCV13 correlated only with PCV13 serotype specific OPA titers after PPSV23 vaccination. Conclusions These findings demonstrate age related differences in immune response and the potential importance of Tfh in modulating functional antibody responses following pneumococcal vaccination.

Loss of T cell immunogenicity due to mutations in virally encoded epitopes is a well-described adaptation strategy to limit host anti-viral immunity. Another described, but less understood, adaptation strategy involves the selection of mutations within epitopes that retain immune recognition, suggesting a benefit for the virus despite continued immune pressure (termed non-classical adaptation). To understand this adaptation strategy, we utilized a single cell transcriptomic approach to identify features of the HIV-specific CD8+ T cell responses targeting non-adapted (NAE) and adapted (AE) forms of epitopes containing a non-classical adaptation. T cell receptor (TCR) repertoire and transcriptome were obtained from antigen-specific CD8+ T cells of chronic (n=7) and acute (n=4) HIV-infected subjects identified by either HLA class I tetramers or upregulation of activation markers following peptide stimulation. CD8+ T cells were predominantly dual tetramer+, confirming a large proportion of cross-reactive TCR clonotypes capable of recognizing the NAE and AE form. However, single-reactive CD8+ T cells were identified in acute HIV-infected subjects only, providing the potential for the selection of T cell clones over time. The transcriptomic profile of CD8+ T cells was dependent on the autologous virus: subjects whose virus encoded the NAE form of the epitope (and who transitioned to the AE form at a later timepoint) exhibited an ‘effective’ immune response, as indicated by expression of transcripts associated with polyfunctionality, cytotoxicity and apoptosis (largely driven by the genes GZMB, IFNɣ, CCL3, CCL4 and CCL5). These data suggest that viral adaptation at a single amino acid residue can provide an alternative strategy for viral survival by modulating the transcriptome of CD8+ T cells and potentially selecting for less effective T cell clones from the acute to chronic phase.

CD8(+) T cell responses restricted by MHC-E, a nonclassical MHC molecule, have been associated with protection in an SIV/rhesus macaque model. The biological relevance of HLA-E–restricted CD8(+) T cell responses in HIV infection, however, remains unknown. In this study, CD8(+) T cells responding to HIV-1 Gag peptides presented by HLA-E were analyzed. Using in vitro assays, we observed HLA-E–restricted T cell responses to what we believe to be a newly identified subdominant Gag-KL9 as well as a well-described immunodominant Gag-KF11 epitope in T cell lines derived from chronically HIV-infected patients and also primed from healthy donors. Blocking of the HLA-E/KF11 binding by the B7 signal peptide resulted in decreased CD8(+) T cell responses. KF11 presented via HLA-E in HIV-infected cells was recognized by antigen-specific CD8(+) T cells. Importantly, bulk CD8(+) T cells obtained from HIV-infected individuals recognized infected cells via HLA-E presentation. Ex vivo analyses at the epitope level showed a higher responder frequency of HLA-E–restricted responses to KF11 compared with KL9. Taken together, our findings of HLA-E–restricted HIV-specific immune responses offer intriguing and possibly paradigm-shifting insights into factors that contribute to the immunodominance of CD8(+) T cell responses in HIV infection.

HIV frequently escapes CD8 T cell responses, leading to the accumulation of viral adaptations. We recently demonstrated that during chronic HIV infection, adapted epitopes can promote maturation of dendritic cells (DCs) through direct CD8 T cell interactions and lead to enhanced HIV trans-infection of CD4 T cells. Here, we sought to determine the role of such adaptations following HIV MRKAd5 vaccination. We observed that vaccine-induced adapted epitope-specific CD8 T cells promoted higher levels of DC maturation than nonadapted ones and that these matured DCs significantly enhanced HIV trans-infection. These matured DCs were associated with higher levels of interleukin 5 (IL-5) and IL-13 and a lower level of CXCL5, which have been shown to impact DC maturation, as well as a lower level of CXCL16. Finally, we observed that vaccine recipients with high HLA-I-associated adaptation became HIV infected more quickly. Our results offer another possible mechanism for enhanced infection among MRKAd5 vaccinees. IMPORTANCE Despite the well-established contribution of CD8 T cells in HIV control, prior CD8 T cell-based HIV vaccines have failed to demonstrate any efficacy in preventing viral infection. One such vaccine, known as the MRKAd5 vaccine, showed a potential increased risk of viral infection among vaccine recipients. However, the underlying mechanism(s) remains unclear. In this study, we observed that vaccine recipients with high adaptation to their HLA-I alleles were associated with an increased HIV infection risk in comparison to the others. Similar to what we observed in HIV infection in the prior study, adapted epitope-specific CD8 T cells obtained from vaccine recipients exhibit a greater capacity in facilitating viral infection by promoting dendritic cell maturation. Our findings provide a possible explanation for the enhanced viral acquisition risk among MRKAd5 vaccine recipients and highlight the importance of optimizing vaccine design with consideration of HLA-I-associated HIV adaptation.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has emerged as a global pandemic. This viral disease primarily causes lung pneumonia and has a wide range of clinical manifestations. The severity of infection ranges from those who are asymptomatic or with mild symptoms which do not require hospital admission, to those who require ventilator support and eventually die, depending on immunity, age and other comorbidities existing with the patients. The present report is an attempt to study the effect of physiological and environmental factors existing at high altitudes (HA) with spread of SARS-CoV-2 infection. Analysis of existing data revealed that HA natives do possess certain physiological advantages such as (1) improved hypoxic ventilatory response, (2) higher concentration of oxygen carrying molecules, haemoglobin, (3) increased production of Vitamin D, due to intense solar radiation, (4) lower rates of comorbidities such as lung infections, obesity etc. and (5) most importantly reduced production of angiotensin converting enzyme 2, a carrier molecule for SARS-CoV-2 virus entry into the host cell; all of which can collectively account for improved tolerance to SARS-CoV-2 infection in HA natives. In addition, environmental factors at HA such as (6) dry and chilly winds, (7) low air density and (8) intense UV radiations may further inhibit viral growth and spread into the atmosphere. We thus conclude that, high altitude natives may posses physiological and environmental advantage over low landers in terms of reduced severity of SARS-CoV-2 infection and its limited spread. Graphic abstract Gift factors associated with COVID-19 spread at high altitude.

Highlights • Coagulation parameters such should be checked at the time of admission of COVID-19 patient. • Measurement of these parameters should continue at regular intervals during entire treatment. • Prophylactic anticoagulation therapy, with LMWH or unfractionated heparin is recommended. • Anticoagulation therapy is strongly recommended patients at high-risk for coagulopathy. • Dose and duration of anti-coagulation therapy should be decided on case to case basis., Background Recent reports on outbreak of SARS-CoV-2 coronavirus (COVID-19) have shown its association with abnormal blood clots. The viral infection initiates inflammatory responses leading to endothelial damage and coagulation cascade dysfnction. Spread of COVID-19 has been associated with disseminated intravascular coagulation (DIC) and subsequent coagulopathy. Initially coagulopathy in COVID-19 patients result in significant elevation of D-dimer, fibrin/fibrinogen degradation products (FDP), and abnormalities in coagulatory parameters, which resulting in formation of thrombus and eventually death. Methodology Present report intends to summarize the information of the research reports available so far on the complications of formation of unusal blood clots (thrombosis) during COVID-19 infection and its therapeutic strategies. Extensive web search was done for various reports associating COVID-19 infection with increased coagulopathy and abnormal coagulatory parameters such as PT, PTT, and platelet counts; along with increased D-dimer and fibrinogen levels. Results and conclusion Findings of these research reports were summarized to recommend cautions for clinicians while treating COVID-19 patient. Screening of coagulatory parameters upon admission and during entire course of treatment is recommended, especially those who are at increased risk of thrombosis. Also, anticoagulant treatment can be used as thromboprophylaxis measure. Dose and duration of anticoagulation treatment requirement may vary and thus regular monitoring is needed.

Breast cancer is the most common cancer among Indian women with a significant increase in incidence in young women. To identify risk factors for breast cancer in young women, study of BRCA1 and BRCA2 germ line mutations was done in a cohort of 204 Indian breast cancer patients. The study showed a total of 18 mutations in 2.94% of the tested patients, 44% BRCA1 and 78% BRCA2 mutations were found unique to the Indian population. Association of low penetrance genes mainly CYP17, VDR gene and AR-CAG repeat polymorphisms with breast cancer risk showed CYP17 A2 and VDR Poly-A L as high risk alleles, the risk of developing breast cancer among women carrying three high-risk alleles is 4.68 (95% confidence interval [CI]: 0.77–28.0; p for trend = 0.10) compared with women carrying none. CYP17 A2 allele was also found associated with development of breast cancer at young age and can also serve as a target for therapy. Betel quid chewing has been found as a significant and independent risk factor for developing breast cancer in North East Indian women which induces genetic alterations leading to breast carcinogenesis. Studies to assess the predictive role of various tumor markers showed that expression of p-glycoprotein in pretreatment biopsy predicts a poor clinical response to neoadjuvant chemotherapy (NACT) in patients having locally advanced breast cancer. The chemotherapy-induced toxicity (vomiting and alopecia) correlated significantly with clinical and immunohistochemical response (reduction in bcl2/bax ratio) and were found to be a cost-effective and reliable predictor of response to NACT. Androgen receptor (AR) has been identified as independent predictive marker for response to NACT in locally advanced breast cancer cases and can serve as novel therapeutic target for triple negative breast cancers.

Ophiocordyceps sinensis (=Cordyceps sinensis), a medicinal mushroom native to the Orient, has been extensively used for the past few centuries in traditional Chinese medicine because of its immunomodulatory, antiinflammatory, and nutraceutical properties. In the present study, three antioxidant and antibacterial Ophiocordyceps peptide fractions (COPs) were separated from the Indian variety of O. sinensis on a Sephadex G-25 resin. Amide bonds in the COPs were confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance. Cationic and hydrophobic amino acids, which are reported to be the major constituent amino acids of antimicrobial peptides, were identified in the COPs by matrix-assisted laser desorption/ionization-mass spectrometry and high-performance liquid chromatography. Putative secondary structures were predicted by circular dichroism to be β-sheets and random coils. The COPs demonstrated substantial antioxidant potential by scavenging 2,2-diphenyl-l-picryl-hydrazyl-hydrate (median inhibitory concentration [IC50] values, 4.79-18.7 mg/mL) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sul-phonic acid (IC50 values, 4.51-14.05 mg/mL) free radicals and also by chelating heavy metal ions. Additionally, the peptide fractions were capable of significantly inhibiting bacterial pathogens viz. Escherichia coli and Salmonella typhi. The potential antibacterial mechanisms of action were established to be generation of reactive oxygen species and intracellular protein leakage within the bacterial cells.

Ganoderma lucidum (G. lucidum) fungus (Family Ganodermataceae) is widely used as a traditional medicine in China, Japan, and many Asian countries on account of its numerous medicinal properties such as antioxidant, anticancer, antimicrobial, energy enhancing, and immunostimulatory. This broad spectrum of therapeutic effects exhibited by G. lucidum is ascribed to its abundance in several classes of chemical constituents, namely, carbohydrates, flavonoids, minerals, phenolics, proteins, and steroids which possess substantial bioactivities. The aim of the current study was to prepare phenolic rich fractions (PRFs) from aqueous extract of the Indian variety of G. lucidum mycelium and fruiting body. These fractions were assessed for their antioxidant capacity by TPC (total phenolic content), TFC (total flavonoid content), FRAP (ferric reducing antioxidant power), and ABTS [2,2-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid] assays. Quantification of flavonoids and nucleobases present in the fractions was carried out by high-performance thin layer chromatography (HPTLC). The antibacterial activity of the fractions was evaluated against Escherichia coli, Salmonella typhi, and Staphylococcus aureus. The antibacterial mechanism of action of the PRFs was established to be generation of reactive oxygen species and leakage of proteins within bacterial cells. Additionally, the protective effect of the PRFs in counteracting hypoxia was observed in HEK 293 cell lines.

A subset of COVID-19 patients exhibit post-acute sequelae of COVID-19 (PASC), but little is known about the immune signatures associated with these syndromes. We investigated longitudinal peripheral blood samples in 50 individuals with previously confirmed SARS-CoV-2 infection, including 20 who experienced prolonged duration of COVID-19 symptoms (lasting more than 30 days; median = 74 days) compared with 30 who had symptom resolution within 20 days. Individuals with prolonged symptom duration maintained antigen-specific T cell response magnitudes to SARS-CoV-2 spike protein in CD4+ and circulating T follicular helper cell populations during late convalescence, while those without persistent symptoms demonstrated an expected decline. The prolonged group also displayed increased IgG avidity to SARS-CoV-2 spike protein. Significant correlations between symptom duration and both SARS-CoV-2-specific T cells and antibodies were observed. Activation and exhaustion markers were evaluated in multiple immune cell types, revealing few phenotypic differences between prolonged and recovered groups, suggesting that prolonged symptom duration is not due to persistent systemic inflammation. These findings demonstrate that SARS-CoV-2-specific immune responses are maintained in patients suffering from prolonged post-COVID-19 symptom duration in contrast to those with resolved symptoms and may suggest the persistence of viral antigens as an underlying etiology.

Ophiocordyceps sinensis, a high-altitude medicinal mushroom, is widely revered in traditional medicine for its antiproliferative, antihypercholesterolemic, energy enhancement, etc. properties. These properties are attributed to the presence of steroids, terpenoids, polyphenolics, glycosides, and glycoproteins in it. The current study presents characterization of three phenolic rich fractions (PRFs) separated from aqueous extract of O. sinensis using diethyl ether and ethyl acetate. These fractions possessed considerable antioxidant potential in terms of total phenolic content, total flavonoid content, ferric ion reducing power, and free radical scavenging efficiency. Chemical characterization of the PRFs was carried out using HPTLC and GC-MS. The diethyl ether and ethyl acetate fractions elucidated appreciable antibacterial activity against Salmonella typhi. The aqueous extract and residual phenolic fraction displayed protective effect on HEK 293 cell lines against hypoxia stress and also bestowed appreciative adaptogenic role against cold, hypoxia, and restraint stress in vivo, by decreasing levels of malondialdehyde and superoxide dismutase and incrementing reduced glutathione concentrations.

T-cell immunity is likely to play a role in protection against SARS-CoV-2 by helping generate neutralizing antibodies. We longitudinally studied CD4 T-cell responses to the M, N, and S structural proteins of SARS-CoV-2 in 21 convalescent individuals. Within the first two months following symptom onset, a majority of individuals (81%) mount at least one CD4 T-cell response, and 48% of individuals mount detectable SARS-CoV-2-specific peripheral T follicular helper cells (pTfh, defined as CXCR5+PD1+ CD4 T cells). SARS-CoV-2-specific pTfh responses across all three protein specificities correlate with antibody neutralization with the strongest correlation observed for S protein-specific responses. When examined over time, pTfh responses increase in frequency and magnitude in convalescence, and robust responses with magnitudes greater than 5% were detected only at the second convalescent visit, an average of 38 days post-symptom onset. These data deepen our understanding of antigen-specific pTfh responses in SARS-CoV-2 infection, suggesting that M and N protein-specific pTfh may also assist in the development of neutralizing antibodies and that pTfh response formation may be delayed in SARS-CoV-2 infection.Author SummarySince December 2019, the Coronavirus Disease 2019 (COVID-19) pandemic has caused significant morbidity and mortality worldwide. Most currently licensed vaccines are understood to protect against infection by inducing neutralizing antibodies. As such, ongoing COVID-19 vaccine trials have focused on antibody neutralization as a primary immunologic endpoint. It is well established that T follicular helper cells are essential to the development of neutralizing antibodies and that a subset of these cells, peripheral T follicular helper cells (pTfh), can be studied in the blood. However, little is known about Tfh responses mounted in SARS-CoV-2 infection. Here, we studied pTfh to three major structural proteins in individuals recovered from COVID-19. We find that SARS-CoV-2-specific pTfh frequencies correlate with neutralizing antibody responses, especially those directed against the spike protein. We also find that pTfh responses to SARS-CoV-2 increase over time. Our findings suggest that pTfh responses against proteins other than the spike protein may contribute to the development of neutralizing antibodies and suggests that formation of pTfh responses in SARS-CoV-2 infection may be delayed.

Enteric fever is a common yet serious issue, most troublesome in underdeveloped and developing nations affecting all age group primarily children. Pitfalls of existing vaccines along with rapidly rising Multi-Drug-Resistant Salmonella strains necessitate the need for the development of new vaccine candidates having potential to provide complete protection. Several vaccine strategies are being pursued to stimulate protective immunity against typhoid, including conjugate vaccines for the elicitation of cellular and humoral responses as both arms of immunity are essential for complete protection. Bacterial HSPs are highly immunogenic to produce humoral and cellular immune responses. In this study, we are reporting in vitro immunostimulatory activity of immunodominant multi-epitope protective antigenic DnaK peptides identified earlier by immunoinformatics approach. Remarkable increase in antibody titer, lymphocyte proliferation, cytokines and NO level with individual /mixture of DnaK peptides as compared to control demonstrate immunogenic potential of these peptides that effectively augments both humoral and cellular immune responses. None of the peptides cause any hemolysis in human RBCs. Overall; our findings strongly elucidate the immune-stimulatory potential of DnaK peptides to be explored as potent vaccine candidates against multiple pathogens.

SARS-CoV-2 causes a wide spectrum of clinical manifestations and significant mortality. Studies investigating underlying immune characteristics are needed to understand disease pathogenesis and inform vaccine design. In this study, we examined immune cell subsets in hospitalized and non-hospitalized individuals. In hospitalized patients, many adaptive and innate immune cells were decreased in frequency compared to healthy and convalescent individuals, with the exception of B lymphocytes which increased. Our findings show increased frequencies of T-cell activation markers (CD69, Ox40, HLA-DR and CD154) in hospitalized patients, with other T-cell activation/exhaustion markers (CD25, PD-L1 and TIGIT) remaining elevated in hospitalized and non-hospitalized individuals. B cells had a similar pattern of activation/exhaustion, with increased frequency of CD69 and CD95 during hospitalization, followed by an increase in PD1 frequencies in non-hospitalized individuals. Interestingly, many of these changes were found to increase over time in non-hospitalized longitudinal samples, suggesting a prolonged period of immune dysregulation following SARS-CoV-2 infection. Changes in T-cell activation/exhaustion in non-hospitalized patients were found to positively correlate with age. Severely infected individuals had increased expression of activation and exhaustion markers. These data suggest a prolonged period of immune dysregulation following SARS-CoV-2 infection highlighting the need for additional studies investigating immune dysregulation in convalescent individuals.

Because of HIV’s vast sequence diversity, the ability of the CD8 T-cell response to recognize several variants of a single epitope is an important consideration for vaccine design. Cross-recognition of viral epitopes by CD8 T cells is associated with viral control during HIV-1 infection, but little is known about CD8 cross-reactivity in the context of HIV-1 vaccination. Here, we evaluated vaccine-induced CD8 cross-reactivity in two preventative HIV-1 vaccine efficacy trials, the MRKAd5 and DNA/rAd5 studies. Cross-reactive CD8 responses elicited by vaccination were similar in magnitude and frequency to those induced during acute HIV-1 infection. Although responses directed against variant epitopes were less avid than responses to vaccine-matched epitopes, we did not detect any difference in response polyfunctionality (the proportion of cells producing multiple effector molecules). And while depth, or the frequency of cross-reactive responses, did not correlate with viral loads in recipients who became infected, cross-reactivity did appear to influence early viral evolution. In comparing viral sequences of placebo versus vaccine recipients, we found that viral sequences from vaccinees encoded CD8 epitopes with more substitutions and greater biochemical dissimilarity. In other words, breakthrough sequences of vaccinees would be less cross-recognized by vaccine-induced responses. Additionally, vaccine-induced CD8 T cells poorly cross-recognized variant epitopes encoding HLA-I-associated adaptations, further supporting our conclusion that these responses play a role in driving early HIV-1 viral evolution. IMPORTANCE HIV-1 has exceptionally high sequence diversity, much of which is found within CD8 epitopes. Therefore, the ability of CD8 T cells to recognize multiple versions of a single epitope could be important for an effective vaccine. Here, we show that two previously tested vaccines induced a similar level of CD8 cross-reactivity to that seen in acute HIV-1 infection. Although this cross-reactivity did not seem to affect viral control in vaccine recipients who became infected, we identified several ways in which CD8 cross-reactivity appeared to influence HIV-1 viral evolution. First, we saw that strains isolated from infected vaccine recipients would likely be poorly cross-recognized by the vaccine-induced response. Second, we saw that adapted CD8 epitopes were poorly cross-recognized in both vaccination and infection. Collectively, we believe these results show that CD8 cross-reactivity could be an important consideration in future HIV-1 vaccine design.

Macroautophagy/autophagy is an auto-digestive pro-survival pathway activated in response to stress to target cargo for lysosomal degradation. In recent years, autophagy has become prominent as an innate antiviral defense mechanism through multiple processes, such as targeting virions and viral components for elimination. These exciting findings have encouraged studies on the ability of autophagy to restrict HIV. However, the role of autophagy in HIV infection remains unclear. Whereas some reports indicate that autophagy is detrimental for HIV, others have claimed that HIV deliberately activates this pathway to increase its infectivity. Moreover, these contrasting findings seem to depend on the cell type investigated. Here, we show that autophagy poses a hurdle for HIV replication, significantly reducing virion production. However, HIV-1 uses its accessory protein Nef to counteract this restriction. Previous studies have indicated that Nef affects autophagy maturation by preventing the fusion between autophagosomes and lysosomes. Here, we uncover that Nef additionally blocks autophagy initiation by enhancing the association between BECN1 and its inhibitor BCL2, and this activity depends on the cellular E3 ligase PRKN. Remarkably, the ability of Nef to counteract the autophagy block is more frequently observed in pandemic HIV-1 and its simian precursor SIVcpz infecting chimpanzees than in HIV-2 and its precursor SIVsmm infecting sooty mangabeys. In summary, our findings demonstrate that HIV-1 is susceptible to autophagy restriction and define Nef as the primary autophagy antagonist of this antiviral process. Abbreviations: 3-MA: 3-methyladenine; ACTB: actin, beta; ATG16L1: autophagy related 16 like 1; BCL2: bcl2 apoptosis regulator; BECN1: beclin 1; cDNA: complementary DNA; EGFP: enhanced green fluorescence protein; ER: endoplasmic reticulum; Gag/p55: group-specific antigen; GFP: green fluorescence protein; GST: glutathione S transferase; HA: hemagglutinin; HIV: human immunodeficiency virus; IP: immunoprecipitation; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; Nef: negative factor; PRKN: parkin RBR E3 ubiquitin ligase; PtdIns3K: phosphatidylinositol 3 kinase; PtdIns3P: phosphatidylinositol 3 phosphate; PTM: post-translational modification; RT-qPCR: reverse transcription followed by quantitative PCR; RUBCN: rubicon autophagy regulator; SEM: standard error of the mean; SERINC3: serine incorporator 3; SERINC5: serine incorporator 5; SIV: simian immunodeficiency virus; SQSTM1/p62: sequestosome 1; TFEB: transcription factor EB; UVRAG: UV radiation resistance associated gene; VSV: vesicular stomatitis virus; ZFYVE1/DFCP1: zinc finger FYVE-type containing 1.