The membrane protein (M) which spans three time the viral membrane has a short N-terminal ectodomain and a cytoplasmic tail. discuss the strategies for the use of chicken egg yolk (IgY) antibodies in the development of rapid diagnosis and immunotherapy against SARS CoV-2. Also, IgY antibodies have previously been used against various respiratory bacterial and viral infections in humans and animals. Compared to mammalian antibodies (IgG), chicken egg yolk antibodies (IgY) have greater binding affinity to specific antigens, ease of extraction and lower production costs, hence Bicalutamide (Casodex) possessing remarkable pathogen-neutralizing activity of pathogens in respiratory and lungs. We provide an overall importance for the use of monoclonal chicken egg yolk antibodies (IgY) using phage display method describing their potential passive immunotherapeutic application for the treatment and prevention of SARS CoV-2 infection which is simple, fast and safe way of approach for treating patients effectively. Keywords: SARS CoV-2, Spike protein (S), IgY, Phage display, Passive immunotherapy 1.?Introduction The novel severe acute respiratory syndrome SARS CoV-2 (nCOVID-19) is a novel coronavirus infection that has emerged as global pandemic threat in todays world. This SARS CoV-2 infection was caused by SARS-associated coronaviruses [1], [2], [3] where the spike protein S were found to be the major domain responsible for mediating the membrane fusion during the infection [4], [5]. Also, the SARS CoV-2 S protein belongs to large membrane glycoprotein and the angiotensin converting enzyme 2 (ACE-2) present in the human cell membranes found to possess the functional receptor for this virus [6]. The conformational changes induced by this complex spike protein (S) with the ACE-2 receptor leads to membrane fusion and furthermore, due to the higher antigenicity nature of S protein, it efficiently elicits the neutralizing antibodies within the system by protecting them from infection [7], [8]. Hence, this spike protein domain (S) will be a good candidate for NGFR developing antiviral drugs, vaccines and that generating high specific antibodies to recognize this domain would be much more valuable. Some of the reported studies with SARS CoV shows that immunization of mice with recombinant spike protein (S) can protect them from infection effectively [7], [8]. Therefore, generating monoclonal antibodies that are specifically to recognize the spike protein (S) is the need of the hour. However, we have to overcome the difficulties in generating highly specific monoclonal antibodies from the traditional way of antibody generation [9], phage display method of monoclonal antibody generation would be safe and effective procedure because of the process of antibody generation by cloning the specific repertoires and subsequent screening Bicalutamide (Casodex) and isolation of monoclonal antibodies from the antibody libraries [10], [11]. Although there are many ways of recombinant antibody generation, the single-chain variable fragments (scFv) of the whole antibody will be an effective region that can be generated in phage display system [12], [13], [14]. Antibody production in chickens is the simplest, easier and efficient way of generating monoclonal antibodies using phage display library selection for scFv gene constructs with higher affinity against targetted pathogens [15], [16]. Also, it has been reported that monospecific scFv antibodies generated using phage display technology has high neutralizing effect against SARS CoV infection that have been generated from non-immunized individuals and convalescent SARS infected individuals [17], [18]. This review focuses to show that the monoclonal IgY scFv antibodies raised against SARS CoV-2 spike protein (S) isolated from chickens using phage display technology would be a potential model for large scale production of high-affinity antibodies effectively. 2.?SARS CoV-2 structure and its etiology The SARS-CoV-2 (nCOVID-19) are enveloped viruses with round Bicalutamide (Casodex) or pleiomorphic structure of approximately 80 to 120?nm in diameter containing positive single-stranded RNA genome of 30?kb size [19], [20]. The RNA genome is complexed with basic nucleocapsid protein (N) to form a helical viral protein and these are spike proteins (S) which are the Type-I glycoprotein that forms the peplomers on the virion surface giving it a crown-like structure (Fig. 1 ). The membrane protein (M) which spans three time the viral.