COVID-19 vaccination produces exercise-responsive SARS-CoV-2 specific T-cells regardless of infection history

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(COVID-19).We sought to determine if COVID-19 vaccination would elicit exercise-responsive SARS-CoV-2 T-cells and transiently alter nAb titers.Methods:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a COVID-19 vaccine.All major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SARS-CoV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TCR)-βsequencing,and SARS-CoV-2 nAb serology.Results:COVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded exercise.However,non-infected participants had a significantly reduced mobilization of CD4+and CD8+naive T-cells,as well as CD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SARS-CoV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SARS-CoV-2 specific T-cells to blood in an intensity-dependent manner.Both groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid antigens.nAbs increased significantly during exercise only in the hybrid immunity group.Conclusion:These data indicate that acute exercise mobilizes SARS-CoV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

Development of donor specific antibodies after SARS-CoV-2 vaccination:What do we know so far?

Vaccination against Coronavirus disease-19(COVID-19)was pivotal to limit spread,morbidity and mortality.Our aim is to find out whether vaccines against COVID-19 lead to an immunological response stimulating the production of de novo donor specific antibodies(DSAs)or increase in mean fluorescence intensity(MFI)of pre-existing DSAs in kidney transplant recipients(KTRs).This study involved a detailed literature search through December 2nd,2023 using PubMed as the primary database.The search strategy incorporated a combination of relevant Medical Subject Headings terms and keywords:"COVID-19","SARS-CoV-2 Vaccination","Kidney,Renal Transplant",and"Donor specific antibodies".The results from related studies were collated and analyzed.A total of 6 studies were identified,encompassing 460 KTRs vaccinated against COVID-19.Immunological responses were detected in 8 KTRs of which 5 had increased MFIs,1 had de novo DSA,and 2 were categorized as either having de novo DSA or increased MFI.There were 48 KTRs with pre-existing DSAs prior to vaccination,but one study(Massa et al)did not report whether pre-existing DSAs were associated with post vaccination outcomes.Of the remaining 5 studies,35 KTRs with pre-existing DSAs were identified of which 7 KTRs(20%)developed de novo DSAs or increased MFIs.Overall,no immunological response was detected in 452(98.3%)KTRs.Our study affirms prior reports that COVID-19 vaccination is safe for KTRs,especially if there are no pre-existing DSAs.However,if KTRs have pre-existing DSAs,then an increased immunological risk may be present.These findings need to be taken cautiously as they are based on a limited number of patients so further studies are still needed for confirmation.

Thyrotoxicosis in patients with a history of Graves'disease after SARS-CoV-2 vaccination(adenovirus vector vaccine):Two case reports

BACKGROUND Vaccines against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)which were approved for emergency use have been administered on a large scale globally to contain the pandemic coronavirus disease 2019(COVID-19)and to save lives.Vaccine safety is one of the issues under surveillance and a possible correlation between vaccines and thyroid function has been reported.However,reports of the impact of coronavirus vaccines on those with Graves’disease(GD)are rare.CASE SUMMARY This paper presents two patients with underlying GD in remission,both developed thyrotoxicosis and one developed thyroid storm following the adenovirus-vectored vaccine(Oxford-AstraZeneca,United Kingdom).The objective of this article is to raise awareness regarding a possible association between COVID-19 vaccination and the onset of thyroid dysfunction in patients with underlying GD in remission.CONCLUSION Receiving either the mRNA or an adenovirus-vectored vaccine for SARS-CoV-2could be safe under effective treatment.Vaccine induced thyroid dysfunction has been reported,but the pathophysiology still not well understood.Further investigation is required to evaluate the possible predisposing factors for developing thyrotoxicosis especially in patients with underlying GD.However,early awareness of thyroid dysfunction following vaccination could avoid a lifethreatening event.

Pooled analysis of efficacy of the fourth mRNA-based COVID-19 vaccine dose in eliciting anti-SARS-CoV-2 serum antibody response in the general immunocompetent population

Objective:Since the opportunity of widespread administration of the fourth mRNA-based coronavirus disease 2019(COVID-19)vaccine dose remains controversial,this article provides a pooled analysis of the efficacy of the second COVID-19 mRNA-based homologous vaccine booster in eliciting anti-SARS-CoV-2 serum antibody response in general immunocompetent populations.Methods:We conducted a digital search in Medline using the keywords"fourth dose"or"second booster"and"antibodies"and"COVID-19"or"SARS-CoV-2"and"BNT162b2"or"mRNA-1273",to identify all clinical studies which evaluated the anti-SARS-CoV-2 serum antibody response after the fourth mRNA-based COVID-19 homologous vaccine dose administration in general immunocompetent populations compared to the response seen before its administration and after the first booster.Results:Four studies totaling 571 recipients of the second mRNA-based COVID-19 vaccine booster were finally included in our analysis.The weighted mean difference(WMD)ratio of anti-SARS-CoV-2 serum antibodies levels measured after and before administration of the fourth vaccine dose was 9.7(95%CI,6.5-12.9)in those receiving BNT162b2 and 12.0(95%CI,5.8-18.2)in those receiving mRNA-1273,respectively.The WMD ratio of anti-SARS-CoV-2 serum antibodies levels measured at the peak of the fourth and third vaccine doses was 1.4(95%CI,1.2-1.7)in those receiving BNT162b2 and 1.9(95%CI,1.5-2.4)in those receiving mRNA-1273,respectively.Conclusion:Our data confirm the efficacy of the fourth mRNA-based COVID-19 vaccine dose in restoring a satisfactory level of anti-SARS-CoV-2 serum antibodies,though such effectiveness seems only marginally superior to that of the first booster.

Expression of Porcine Interleukin-2 and Porcine Interleukin-6 and Their Adjuvant Effects on Gene Deleted Vaccine of Pseudorabies Virus(TK^-/gG^-/LacZ^+)

Porcine interleukin-2 and porcine interleukin-6 cDNA sequences were cloned into the expressing vectors pET-28a and pGEX-KG respectively. They were expressed in E. coli BL21(DE3)with high-level production. The gene deleted vaccine of pseudorabies virus Ea strain(TK-/gG-/LacZ+)was mixed with the two different purified recombinant proteins each, or both, with the doses of 2, 5 or 10 μg ml-1. Ten groups of pseudorabies negative antibody swines were immuned twice with tested vaccines with different doses, or control vaccine, respectively. The antibody liters of the test groups were detected by neutralization test, and the daily weight gains of swines were calculated and analyzed statistically. In the study, all the neutralizing antibody ti-ters in test groups were higher than the control group, and the recombinant proteins appeared a dose dependent adjuvant effect. The tested vaccines with 2 μg ml-1 pIL-2 and with 10 μg ml-1 pIL-2/pIL-6 got significant and extremely significant differences, compared with the vaccines without pILs. The difference of the daily weight gain indicated the potential positive influence of pIL-2 and pIL-6 on immune protection.

重组SARS-CoV-2 Omicron变异株S1蛋白的表达及免疫原性评价

目的构建表达新型冠状病毒(SARS-CoV-2)Omicron BA.1变异株S1蛋白的真核表达载体,在CHO-K1细胞中进行表达,评价其免疫原性,并对佐剂和抗原剂量进行研究。方法构建重组质粒UCOE-Omi-S1,转染至CHO-K1工程细胞中进行表达和纯化,通过SDS-PAGE和Western blot法实验鉴定重组S1蛋白。将BALB/c小鼠随机分为12组,即PBS组,无佐剂组(高、中、低剂量组),铝盐佐剂对照组,MF59佐剂对照组,铝盐佐剂实验组(高、中、低剂量组),MF59佐剂实验组(高、中、低剂量组),将按照分组要求配比的溶液经小鼠肌内注射3次,间隔14天,每2周尾静脉采血,末次免疫30天后取血分离血清,酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测血清抗体水平,并和SARS-CoV-2原型株的假病毒和SARS-CoV-2 Omicron BA.1变异株的假病毒进行假病毒中和实验。结果目的蛋白在CHO-K1工程细胞表达后可分泌到培养上清中,在相对分子质量约为70kDa处可见1条特异性蛋白表达条带,经Western blot法鉴定为Omi-S1蛋白。铝盐佐剂组和MF59佐剂组免疫诱导效果优于无佐剂组,铝盐佐剂组和MF59佐剂组免疫诱导效果相差不大,但MF59佐剂起效快;高、中、低剂量组的免疫诱导效果在第8周相差不大,但高剂量组起效快。假病毒中和实验表明,MF59佐剂实验组针对Omicron变异株的中和抗体水平高于铝盐佐剂组。结论本研究所构建的Omicron S1重组蛋白免疫原性良好,在小鼠体内产生了良好的体液免疫应答,并诱导高水平的对抗SARS-CoV-2假病毒的中和抗体,对佐剂和抗原剂量初步研究,结果显示,10μg以下抗原剂量搭配MF59佐剂可获得较好的免疫效果。本研究为SARS-CoV-2变异株的重组蛋白疫苗的研制提供了实验基础。

Clinical application of COVID-19 vaccine in liver transplant recipients

Background:Solid organ transplant(SOT)activities,such as liver transplant,have been greatly influenced by the pandemic of coronavirus disease 2019(COVID-19),a disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Immunosuppressed individuals of liver transplant recipients(LTRs)tend to have a high risk of COVID-19 infection and related complications.Therefore,COVID-19 vaccination has been recommended to be administered as early as possible in LTRs.Data sources:The keywords“liver transplant”,“SARS-CoV-2”,and“vaccine”were used to retrieve articles published in PubMed.Results:The antibody response following the 1st and 2nd doses of vaccination was disappointingly low,and the immune responses among LTRs remarkably improved after the 3rd or 4th dose of vaccination.Although the 3rd or 4th dose of COVID-19 vaccine increased the antibody titer,a proportion of patients remained unresponsive.Furthermore,recent studies showed that SARS-CoV-2 vaccine could trigger adverse events in LTRs,including allograft rejection and liver injury.Conclusions:This review provides the recently reported data on the antibody response of LTRs following various doses of vaccine,risk factors for poor serological response and adverse events after vaccination.

Accurate Diagnosis of SARS-CoV-2 JN.1 by Sanger Sequencing of Receptor-Binding Domain Is Needed for Clinical Evaluation of Its Immune Evasion

Background: Omicron JN.1 has become the dominant SARS-CoV-2 variant in recent months. JN.1 has the highest number of amino acid mutations in its receptor binding domain (RBD) and has acquired a hallmark L455S mutation. The immune evasion capability of JN.1 is a subject of scientific investigation. The US CDC used SGTF of TaqPath COVID-19 Combo Kit RT-qPCR as proxy indicator of JN.1 infections for evaluation of the effectiveness of updated monovalent XBB.1.5 COVID-19 vaccines against JN.1 and recommended that all persons aged ≥ 6 months should receive an updated COVID-19 vaccine dose. Objective: Recommend Sanger sequencing instead of proxy indicator to diagnose JN.1 infections to generate the data based on which guidelines are made to direct vaccination policies. Methods: The RNA in nasopharyngeal swab specimens from patients with clinical respiratory infection was subjected to nested RT-PCR, targeting a 398-base segment of the N-gene and a 445-base segment of the RBD of SARS-CoV-2 for amplification. The nested PCR amplicons were sequenced. The DNA sequences were analyzed for amino acid mutations. Results: The N-gene sequence showed R203K, G204R and Q229K, the 3 mutations associated with Omicron BA.2.86 (+JN.1). The RBD sequence showed 24 of the 26 known amino acid mutations, including the hallmark L455S mutation for JN.1 and the V483del for BA.2.86 lineage. Conclusions: Sanger sequencing of a 445-base segment of the SARS-CoV-2 RBD is useful for accurate determination of emerging variants. The CDC may consider using Sanger sequencing of the RBD to diagnose JN.1 infections for statistical analysis in making vaccination policies.

Symmetric DWI hyperintensities in CMT1X patients after SARS-CoV-2 vaccination should not be classified as stroke-like lesions

The interesting case report by Zhang et al on a 39 years-old male with Charcot-Marie-Tooth disease type 1X has several limitations.The causal relation between the two episodes of asyndesis,dysphagia,and dyspnea 37 d after the second dose of the inactivated severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2)vaccine(Beijing Institute of Biological Products Co.,Ltd.,Beijing,China)remains unproven.SARS-CoV-2 vaccination cannot trigger a genetic disorder.It also remains unsupported that the patient had a stroke-like episode(SLE).SLEs occur in mitochondrial disorders but not in hereditary neuropathies.Because of the episodic nature of the neurological symptoms,it is critical to rule out seizures.Overall,the causal relation between vaccination and the neurological complications remains unsupported and the interpretation of symmetric diffusionweighted imaging lesions on cerebral magnetic resonance imaging should be carefully revised.

X-linked Charcot-Marie-Tooth disease after SARS-CoV-2 vaccination mimicked stroke-like episodes: A case report

BACKGROUND Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) vaccinations have been administered worldwide, with occasional reports of associated neurological complications. Specifically, the impact of vaccinations on individuals with Xlinked Charcot-Marie-Tooth disease type 1(CMTX1) is unclear. Patients with CMTX1 can have stroke-like episodes with posterior reversible encephalopathy syndrome on magnetic resonance imaging(MRI), although this is rare.CASE SUMMARY A 39-year-old man was admitted with episodic aphasia and dysphagia for 2 d. He received SARS-CoV-2 vaccination 39 d before admission. Physical examination showed pes cavus and reduced tendon reflexes. Brain MRI showed bilateral, symmetrical, restricted diffusion with T2 hyperintensities in the cerebral hemispheres. Nerve conduction studies revealed peripheral nerve damage. He was diagnosed with Charcot-Marie-Tooth disease, and a hemizygous mutation in the GJB1 gene on the X chromosome, known to be pathogenic for CMTX1, was identified. Initially, we suspected transient ischemic attack or demyelinating leukoencephalopathy. We initiated treatment with antithrombotic therapy and immunotherapy. At 1.5 mo after discharge, brain MRI showed complete resolution of lesions, with no recurrence.CONCLUSION SARS-CoV-2 vaccination could be a predisposing factor for CMTX1 and trigger a sudden presentation.

Evolution of Acquired Humoral Immunity after Full Vaccination against SARS-CoV-2. IgG Levels in Healthcare Workers at 6 and 9 Months

Background: The COVID-19 pandemic continues to be a major worldwide health problem. The present study aims to contribute to surveillance of the immune and clinical response of vaccines to SARS-CoV-2. Methods: Observational medication study on acquired immunity and effectiveness of vaccines. Population: 620 workers in the health service of Almansa (Spain). Representative sample of 150 individuals. Sociodemographic, clinical, and epidemiological data and samples were recorded to determine anti-SARS-CoV-2 serum IgG levels 6 and 9 months after vaccination with Pfizer. Results: Mean age 46.45 years;76% women;85.1% working in a hospital. 19.3% had had COVID-19 in the year prior to vaccination. 96.7% were fully vaccinated with Pfizer/BioNTech. At 6 months, 100% seropositivity and mean IgG levels of 3017.2 AU/ml. Significant variations in IgG levels in individuals with prior COVID-19 infection and smokers. At 9 months, 99.3% remained seropositive;2.8% infected after vaccination. The repeated measures analysis showed a difference in means of 669.0 AU/ml (significant decrease in IgG levels of 28.9%). Conclusion: Antibody levels remained positive 6 and 9 months after vaccination, although IgG levels were found to decay.

SARS-CoV-2 vaccine research and development: Conventional vaccines and biomimetic nanotechnology strategies

The development of a massively producible vaccine against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),a novel coronavirus,is essential for stopping the current coronavirus disease(COVID-19)pandemic.A vaccine must stimulate effective antibody and T cell responses in vivo to induce long-term protection.Scientific researchers have been developing vaccine candidates for the severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS)since the outbreaks of these diseases.The prevalence of new biotechnologies such as genetic engineering has shed light on the generation of vaccines against novel viruses.In this review,we present the status of the development of coronavirus vaccines,focusing particularly on the biomimetic nanoparticle technology platform,which is likely to have a major role in future developments of personalized medicine.

Intranasal Immunization Using CTA1-DD as a Mucosal Adjuvant for an Inactivated Influenza Vaccine

Objective To evaluate the effect of intranasal immunization with CTA1-DD as mucosal adjuvant combined with H3N2 split vaccine. Methods Mice were immunized intranasally with PBS(negative control), or H3N2 split vaccine(3 μg/mouse) alone, or CTA1-DD(5 μg/mouse) alone, or H3N2 split vaccine(3 μg/mouse) plus CTA1-DD(5 μg/mouse). Positive control mice were immunized intramuscularly with H3N2 split vaccine(3 μg/mouse) and alum adjuvant. All the mice were immunized twice, two weeks apart. Then sera and mucosal lavages were collected. The specific HI titers, IgM, IgG, IgA, and IgG subtypes were examined by ELISA. IFN-γ and IL-4 were test by ELISpot. In addition, two weeks after the last immunization, surivival after H3N2 virus lethal challenge was measured. Results H3N2 split vaccine formulated with CTA1-DD could elicit higher Ig M, Ig G and hemagglutination inhibition titers in sera. Furthermore, using CTA1-DD as adjuvant significantly improved mucosal secretory Ig A titers in bronchoalveolar lavages and vaginal lavages. Meanwhile this mucosal adjuvant could enhance Th-1-type responses and induce protective hemagglutination inhibition titers. Notably, the addition of CTA1-DD to split vaccine provided 100% protection against lethal infection by the H3N2 virus. Conclusion CTA1-DD could promote mucosal, humoral and cell-mediated immune responses, which supports the further development of CTA1-DD as a mucosal adjuvant for mucosal vaccines.

SARS-Cov-2 Delayed Tokyo 2020 Olympics: Very Recent Advances in COVID-19 Detection, Treatment, and Vaccine Development Useful Conducting the Games in 2021

The novel coronavirus (SARS-Cov-2) delayed the Tokyo 2020 Games. The traveling by air, rail, road, and sea inside and outside the countries has stopped to contain the virus. The amount of money lost and assistance needed to reschedule and conduct the Games in 2021 have been estimated. With more than one billion population is under the semi-locked down and movement of people is restricted, athletes cannot prepare at home and participate in the Games. The COVID-19 outbreak has spread around the world;it has already infected 5.7 million people and caused 355,000 deaths reported on May 28, 2020 and the figures increasing every day. The publication of this article is important as the postponement of the Olympics has costed Japan $6 billion and the organizers have worked very hard for seven years. If the Games are conducted in 2021, it will be the—beginning of the world recovery—from big COVID-19 pandemic. In this communication, the development in testing, treatment, and vaccine preparation for SARS-Cov-2 have occurred so far in different countries and companies have been discussed to know the possibilities if the pandemic can be overcome and the Games can be conducted in 2021.

A Vaccine Based on the Receptor-Binding Domain of the Spike Protein Expressed in Glycoengineered Pichia pastoris Targeting SARS-CoV-2 Stimulates Neutralizing and Protective Antibody Responses

In 2020 and 2021,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),a novel coronavirus,caused a global pandemic.Vaccines are expected to reduce the pressure of prevention and control,and have become the most effective strategy to solve the pandemic crisis.SARS-CoV-2 infects the host by binding to the cellular receptor angiotensin converting enzyme 2(ACE2)via the receptor-binding domain(RBD)of the surface spike(S)glycoprotein.In this study,a candidate vaccine based on a RBD recombinant subunit was prepared by means of a novel glycoengineered yeast Pichia pastoris expression system with characteristics of glycosylation modification similar to those of mammalian cells.The candidate vaccine effectively stimulated mice to produce high-titer anti-RBD specific antibody.Furthermore,the specific antibody titer and virus-neutralizing antibody(NAb)titer induced by the vaccine were increased significantly by the combination of the double adjuvants Al(OH)_(3) and CpG.Our results showed that the virus-NAb lasted for more than six months in mice.To summarize,we have obtained a SARS-CoV-2 vaccine based on the RBD of the S glycoprotein expressed in glycoengineered Pichia pastoris,which stimulates neutralizing and protective antibody responses.A technical route for fucose-free complex-type N-glycosylation modified recombinant subunit vaccine preparation has been established.

Human IgM and IgG Responses to an Inactivated SARS-CoV-2 Vaccine

Objective:The ongoing COVID-19 pandemic warrants accelerated efforts to test vaccine candidates.To explore the influencing factors on vaccine-induced effects,antibody responses to an inactivated SARS-CoV-2 vaccine in healthy individuals who were not previously infected by COVID-19 were assessed.Methods:All subjects aged 18-60 years who did not have SARS-CoV-2 infection at the time of screening from June 19,2021,to July 02,2021,were approached for inclusion.All participants received two doses of inactivated SARS-CoV-2 vaccine.Serum IgM and IgG antibodies were detected using a commercial kit after the second dose of vaccination.A positive result was defined as 10 AU/mL or more and a negative result as less than 10 AU/mL.This retrospective study included 97 infection-naive individuals(mean age 35.6 years;37.1%male,62.9%female).Results:The seropositive rates of IgM and IgG antibody responses elicited after the second dose of inactivated SARS-CoV-2 vaccine were 3.1%and 74.2%,respectively.IgG antibody levels were significantly higher than IgM levels(P<0.0001).Sex had no effect on IgM and IgG antibody response after the second dose.The mean anti-IgG level in older persons(≥42 years)was significantly lower than that of younger recipients.There was a significantly lower antibody level at>42 days compared to that at 0-20 days(P<0.05)and 21-31 days(P<0.05)after the second dose.Conclusion:IgG antibody response could be induced by inactivated SARS-CoV-2 vaccine in healthy individuals(>18 years),which can be influenced by age and detection time after the second dose of vaccination.

Research Progress on a SARS-CoV-2 Vaccine in China

Although many countries have controlled the pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through strict management, there are still many countries with record-breaking numbers of new cases. Therefore, it is very important to develop a vaccine that can cause wide cross reactivity in clinical trials. At present, more than 90 vaccines are entering clinical trials and progressing smoothly, including inactivated vaccines, adenovirus-vectored vaccines and other types of vaccines. Here, we review and summarize the efficacy and potential threats of a SARS-CoV-2 vaccine. We reviewed whole-virus vaccines, adenovirus-subunit vaccines and recombinant protein vaccines and discussed the positive and negative consequences of a SARS-CoV-2 vaccine. However, there are still heated debates on the mechanism, effectiveness, and breadth of protection. In conclusion, this study can predict the risk of new coronavirus outbreaks in the future by discussing the research and development status of new coronavirus vaccines in China and other countries. Looking to the future, it is important to mine the large amount of data generated in clinical trials of universal new coronavirus vaccines to ensure that these vaccine programs are equally useful in the face of new coronavirus mutations.

Efficacy and safety profile of two-dose SARS-CoV-2 vaccines in cancer patients:An observational study in China

BACKGROUND The new coronavirus severe acute respiratory syndrome coronavirus 2(SARSCoV-2)has produced a global pandemic of coronavirus disease 2019(COVID-19),resulting in modifications to public health policies on a universal scale.SARSCoV-2 vaccine has evolved as the most effective and secure way for protecting healthy individuals against COVID-19.Patients with cancer were excluded from clinical trials due to their increased COVID-19 risk and current immunosuppressing therapy.Safety and effectiveness evidence is insufficient for SARS-CoV-2 vaccination in cancer patients.AIM To assess the efficacy and safety of two-dose SARS-CoV-2 vaccines in cancer patients.METHODS A multicenter observational study was performed at ten Chinese hospitals between January 1,2021 and December 31,2021.Each participant in the research received two doses of vaccination.A total of 215 healthy people were screened and 132 eligible patients with cancer were recruited.In order to verify the safety of the second dose of the vaccine,a side-effect report was compiled.Two weeks following the second vaccination dose,subjects underwent an analogous questionnaire survey.Utilizing a magnetic particle-based chemiluminescence immunoassay,serum levels of anti-SARS-CoV-2 immunoglobulin G(IgG)antibodies were measured to determine the effectiveness of vaccination.IgG levels≥10 AU/mL were considered seropositive.RESULTS All the 347 eligible patients completed the follow-up,and anti-SARS-CoV-2 IgG antibodies were detected.Local pain at the injection location was the most common side effect mentioned by all responders,with an increased incidence in cancer patients than the healthy people after the second dose vaccine(17.2%vs 9.1%;P=0.035).There was no significant difference in headache,urticaria,or other adverse reactions between patients with cancer and healthy people.In the group of cancer patients,the seropositivity incidence was 83.3%,while it was 96.3%in the group of healthy people.In the group of cancer patients,the seropositivity incidence and antibody levels were significantly lower(P<0.001).This analysis showed a poorer response rate in patients on active immunosuppressive treatment and elderly cancer patients.CONCLUSION Two-dose Chinese vaccines are effective and safe in cancer patients.However,further research is required on the efficacy in elderly cancer patients and those on active immunosuppressive treatment.

Sex differences in SARS-CoV-2 infections,anti-viral immunity and vaccine responses

The COVID-19 pandemic has revealed sex-based differences in anti-viral responses,with a higher rate of SARS-CoV-2 infections as well as a higher rate of morbidity and mortality in men than in women.Males and females also show disparate immune responses to COVID-19 infection,which may be important contributors to lower rates of infection,disease severity and deaths in women than in men.Here,the authors review sex differences in SARS-CoV-2 infections,anti-viral immunity and vaccine responses,putting forth the importance of sex,the underappreciated variables in vaccine response and disease infectivity.

Case series in Indonesia:B.1.617.2(delta)variant of SARS-CoV-2 infection after a second dose of vaccine

BACKGROUND The B.1.617.2(delta)variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was first discovered in Maharashtra in late 2020 and has rapidly expanded across India and worldwide.It took only 2 mo for this variant to spread in Indonesia,making the country the new epicenter of the delta variant as of July 2021.Despite efforts made by accelerating massive rollouts of current vaccines to protect against infection,cases of fully-vaccinated people infected with the delta variant have been reported.AIM To describe the demographic statistics and clinical presentation of the delta variant infection after the second dose of vaccine in Indonesia.METHODS A retrospective,single-centre case series of the general consecutive population that worked or studied at Faculty of Medicine,Universitas Indonesia with confirmed Delta Variant Infection after a second dose of vaccine from 24 June and 25 June 2021.Cases were collected retrospectively based on a combination of author recall,reverse transcription-polymerase chain reaction(RT-PCR),and whole genome sequencing results from the Clinical Microbiology Laboratory,Faculty of Medicine,Universitas Indonesia.RESULTS Between 24 June and 25 June 2021,15 subjects were confirmed with the B.1.617.2(delta)variant infection after a second dose of the vaccine.Fourteen subjects were vaccinated with CoronaVac(Sinovac)and one subject with ChAdOx1 nCoV-19(Oxford-AstraZeneca).All of the subjects remained in home isolation,with fever being the most common symptom at the onset of illness(n=10,66.67%).The mean duration of symptoms was 7.73 d(±5.444).The mean time that elapsed from the first positive swab to a negative RT-PCR test for SARS-CoV-2 was 17.93 d(±6.3464).The median time that elapsed from the second dose of vaccine to the first positive swab was 87 d(interquartile range:86-128).CONCLUSION Although this case shows that after two doses of vaccine,subjects are still susceptible to the delta variant infection,currently available vaccines remain the most effective protection.They reduce clinical manifestations of COVID-19,decrease recovery time from the first positive swab to negative swab,and lower the probability of hospitalization and mortality rate compared to unvaccinated individuals.